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Ethylene polymers made from phosphate supported chromium catalyst
In accordance with one embodiment of this invention, a chromium catalyst supported on an aluminum phosphate-containing base is used in conjunction with a boron component either as a part of the base or as a cocatalyst. The resulting catalyst is unique both in its favorable sensitivity to molecular weight control agents such as hydrogen and in its ability to produce a fundamentally different olefin polymer. In accordance with another embodiment of this invention, the chromium is supported on a phosphate base produced using a melt of the aluminum salt.
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This invention relates to a phosphate supported chromium catalyst for olefin polymerization.
Supported chromium oxide catalysts can be used to prepare olefin polymers in a hydrocarbon solution to give a product having excellent characteristics from many standpoints. Silica supported chromium oxide catalysts can also be used to prepare olefin polymers in a slurry system wherein the polymer is produced in the form of small particles of solid material suspended in a diluent. This process, frequently referred to as a particle-form process, has the advantage of being less complex. However, certain control operations which are easily carried out in the solution process are considerably more difficult in the particle-form process. For instance, in the solution process, control of the molecular weight can be effected by changing the temperature with lower molecular weight (higher melt flow) being obtained at the higher temperature. However, in the slurry process, this technique is inherently limited since any efforts to increase the melt flow to any appreciable extent by increasing temperature would cause the polymer to go into solution and thus destroy the slurry or particle-form process. It is known to extend the range of melt flow capability of a given catalyst through the use of hydrogen. However, it has not heretofore been commercially feasible to produce a complete spectrum of polymers so far as melt flow is concerned in a slurry system with a single chromium catalyst system. Also, it is frequently desired to have a polymer with greater shear response than is normally obtained in the slurry or particle-form process.
While it has long been known to use phosphates as supports for chromium olefin polymerization catalysts, such supports have never achieved commercial success. Thus chromium catalysts are generally supported on silica-containing bases similar to those used decades ago when the chromium catalyzed polymerization of olefin polymers first became commercial.SUMMARY OF THE INVENTION
It is an object of this invention to provide a catalyst capable of giving both high melt flow and high shear response;
it is a further object of this invention to provide a catalyst suitable for use in slurry polymerization systems;
it is yet a further object of this invention to provide a catalyst capable of giving polymer suitable for blow molding and other applications requiring good melt strength;
it is yet a further object of this invention to provide a catalyst capable of producing olefin polymers having unexpectedly high flexural modulus;
it is yet a further object of this invention to provide a single catalyst system capable of giving a broad spectrum of polymers so far as melt flow is concerned;
it is a further object of this invention to provide an improved phosphate supported chromium catalyst system for olefin polymerization;
it is yet a further object of this invention to provide a catalyst system having unusual sensitivity to molecular weight control agents such as hydrogen;
it is still yet a further object of this invention to produce a novel olefin polymer definable in terms of a combination of physical properties without resort to the method used to produce it; and
it is still yet a further object of this invention to produce a thermoplastic polymer having resistance to stress cracking which is an order of magnitude greater than would be expected for a given density or flexural modulus.
In accordance with one embodiment of this invention, a chromium catalyst supported on an aluminum phosphate-containing base is used in conjunction with a boron component either as a part of the base or as a cocatalyst. In accordance with a second embodiment of this invention, a chromium catalyst is supported on a phosphate-containing base prepared by combining a molten aluminum salt with phosphoric acid or a phosphoric acid salt and then forming aluminum phosphate which is recovered and activated by calcining in air.BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a plot showing the relationship of (1) surface hydroxyl concentration, (2) activity, and (3) melt index, to aluminum to phosphorus ratio;
FIG. 2 is a plot similar to FIG. 1 showing the relationship of activity to various activation temperatures;
FIG. 3 is a plot of stress crack resistance versus flexural modulus for polymers of the invention and for prior art polymers;
FIG. 4 is a plot of melt index versus shear response; and
FIG. 5 is a plot of molecular weight distribution versus shear response.DESCRIPTION OF THE PREFERRED EMBODIMENTS
Any suitable method can be used to prepare the base. Three suitable methods are set out hereinafter. First, conventional techniques as disclosed in Hill et al, U.S. Pat. No. 4,219,444, the disclosure of which is hereby incorporated by reference can be used. In this method an aluminum salt is combined with a source of phosphate ions in an aqueous medium and neutralized with a neutralizing agent to give a hydrogel. Alternatively, a polar organic solvent can be used. The second method for forming the base of the catalyst system of this invention is to combine an aluminum alkoxide with phosphoric acid to give a hydrogel directly, as disclosed in Pine, U.S. Pat. No. 3,904,550, the disclosure of which is hereby incorporated by reference. Third, an aluminum salt which will melt can be used, with the source of phosphate ions combined with the melt and then neutralized to give the hydrogel. Generally those aluminum salts with a sufficiently low melting point are hydrated. Orthophosphoric acid, orthophosphates such as monoammonium phosphate and diammonium hydrogen phosphate or mixtures of monoammonium and diammonium phosphate are preferred sources of phosphate ions. The scope of the phosphate ion source can be the same as in the first method. In a variation of this third method, a concentrated syrup of an aluminum salt is used. Thus, the third method can be broadly viewed as employing a concentrated mass of the acid phase (source of aluminum and source of orthophosphate ions). Alternatively, in method three and possibly method one, the aluminum-phosphate composition can be only partially neutralized and allowed to sit as a strongly acid composition until gellation occurs spontaneously.
In the preparations involving an aqueous medium, it is preferred to remove water by azeotropic distillation or by washing with a volatile, water miscible, low surface tension organic liquid. In the techniques not employing water or a solvent, any small amount of water carried over from water of hydration or from the base used in the neutralization can be removed by conventional spray drying, tray drying or oven drying, thus avoiding the necessity for azeotropic distillation. However, even in these situations, if it is desired to water wash the hydrogel, then azeotropic distillation or washing with a volatile oxygen containing water miscible solvent is desirable. After drying of water in this manner, the gel is preferably dried of solvent under mild conditions, for instance by heating at a temperature of 25.degree. to 110.degree. C., most preferably under vacuum.
It may be desirable in some instances to coprecipitate other materials with the phosphate or have other materials present during the gellation. For instance, the chromium compound such as chromium nitrate can be introduced with the reactants, as can a silicon component such as Si(OEt).sub.4.
It is frequently preferred that a small amount of a boron compound such as B(OH).sub.3 be introduced into the melt to be coprecipitated with the aluminum phosphate. Other suitable boron compounds include borates such as ammonium borate. By coprecipitated as it relates to the boron compound, it is meant that the aluminum phosphate is formed into a true hydrogel in the presence of the boron compound. It is not known to what extent the borate becomes incorporated into the hydrogel structure. The amount of boron compound present when the aluminum phosphate is gelled can vary widely but it is generally used in an amount so as to give about 1 to 30 mole percent boron compound based on the moles of phosphate.
The neutralization in the first and third methods can be carried out either by adding the acid phase to the base phase or vice versa (or by adding both to a third vessel). One suitable practice is to drip the acid phase into the base phase. This results in the production of small spheres or balls of the orthophosphate, particularly with the third method where the melt of aluminum salt and source of phosphate ions is dripped or sprayed or otherwise slowly added to a large excess of ammonium hydroxide. The spheres are subsequently collected, washed, dried and calcined.
Gellation occurs spontaneously at a pH of about 4, which is achieved by combining about 72 percent of the neutralizing agent, and it has been found, particularly in technique three, that this is undesirable. Therefore, neutralization is preferably achieved by either: (1) combining slowly with stirring about 72 percent of the amount of neutralizing agent needed for complete neutralization and thereafter quickly adding the rest so as to achieve gellation at a pH of 5 or greater, preferably at least 6, generally 6 to 10, or (2) combining 60 to 70 percent of the neutralizing agent needed for complete neutralization and aging until gellation occurs which will generally be 1 minute to 48 hours, more generally 5 minutes to 10 hours, more generally 10 minutes to 3 hours; thus, gellation occurs at a pH below 4, generally about 2. While any base can be used, concentrated ammonium hydroxide, ammonia gas, or ammonia dissolved in an alcohol or other non-aqueous solvent are preferred. Other suitable neutralizing agents include ammonium carbonate used alone or in combination, ethylene oxide and propylene oxide. Alternatively, in techniques one and three, particularly one, the phosphate can be in the nautralizing agent.
The chromium can be coprecipitated as noted hereinabove or can be added to the hydrogel. For example, a water soluble chromium compound, such as chromium nitrate, chromium acetate, or CrO.sub.3 can be added to the hydrogel. Alternatively, a chromium compound soluble in an anhydrous solvent such as hydrocarbon can be used to impregnate the xerogel prior to activation. Suitable chromium compounds for such anhydrous impregnation include tertiary-butyl chromate. The chromium compounds are used in amounts sufficient to give 0.001 to 10, preferably 0.1 to 5, more preferably about 1 weight percent chromium based on the weight of the xerogel base. (The term xerogel is used to refer to the predominantly amorphous gel resulting from the removal of free water from the hydrogel.)
The activation of the thus-formed xerogel can be carried out at a lower temperature than is generally required for activating silica-based chromium catalysts which is a major advantage for the invention. Temperatures of 150.degree.-800.degree. C., preferably 300.degree.-800.degree. C., more preferably 300.degree.-600.degree. C., are suitable. The activating ambient can be any oxidizing ambient but for convenience and economy, an oxygen-containing ambient such as air is preferred. The chromium is at least predominantly in the hexavalent state after activation. If an excess of chromium over what is required is used, the excess may not be in the hexavalent state, if it remains on the catalyst at all. Times of 5 minutes to 24 hours, preferably 0.5 to 10 hours, are suitable for the activation or calcining step. The chromium is thought to be reduced in the polymerization zone by the monomer, probably to plus two oxidation state. If desired, this reduction may be carried out before the catalyst is contacted with the monomer, for instance in the activator.
The aluminum and phosphorus components are selected so as to give an atom ratio of phosphorus to aluminum within the range of 0.2:1 to 1:1, preferably 0.6:1 to 0.9:1. FIG. 1 shows the relationship between aluminum to phosphorus atom ratio and activity and melt index. Ratios above 1 are undesirable because the xerogel tends to be crystalline as opposed to amorphous and because excess phosphorus may deactivate the chromium.
Based on superior results obtained with triethylborane and tri-n-butyl borane, the boron cocatalyst is preferably a trihydrocarbylborane, more preferably a trialkylborane, the alkyl groups preferably having 1 to 12, more preferably 2 to 5, carbon atoms per group. Triethylborane, tripropylborane and tributylborane are presently believed to be especially preferred. Tri-n-butylborane is presently most preferred because it gives greater MI increase than the others tested. Other boron compounds such as boron alkoxides, for instance B(C.sub.2 H.sub.5).sub.2 OC.sub.2 H.sub.5, alkyl haloboron compounds, for instance BC.sub.2 H.sub.5 Cl.sub.2, aryl borons such as triphenylborane and metal aryl borate (MBR.sub.4) can also be used. The boron compound cocatalyst is generally utilized in an amount so as to give an atom ratio of boron to chromium within the range of 0.5:1 to 15:1, preferably 2:1 to 10:1. This is based on test results indicating that lower amounts are progressively less effective and higher amounts, while operable, do not give any appreciable added benefit. Based on the solvent if any, these amounts of boron compound cocatalyst correspond to a range of 0.5 to 20, preferably 2 to 10 parts by weight per million parts by weight of the solvent, these amounts being based on the total reactor contents in instances where no solvent is utilized.
The boron-containing cocatalyst can either be premixed with the catalyst or added as a separate stream to the polymerization zone, the latter being preferred.
The catalysts of this invention can be further treated in the same manner as chromium on silica catalysts are sometimes given special treatments such as being fluorided or being reduced and reoxidized by, for instance high temperature treatment in CO followed by activation as described herein in an oxidizing ambient.
The catalyst of this invention comprising a chromium compound on a predominantly amorphous aluminum phosphate-containing xerogel base can be used to polymerize at least one mono-1-olefin containing 2 to 8 carbon atoms per molecule. The invention is of particular applicability in producing ethylene homopolymers and copolymers from mixtures of ethylene and one or more comonomers selected from 1-olefins containing 3 to 8 carbon atoms per molecule. Exemplary comonomers for use with ethylene include aliphatic 1-olefins, such as propylene, 1-butene, 1-pentene, 1-hexene, 1-octene and other higher olefins and conjugated or non-conjugated diolefins such as 1,3-butadiene, isoprene, piperylene, 2,3-dimethyl-1,3-butadiene, 1,4-pentadiene, 1,7-hexadiene, and other such diolefins and mixtures thereof. Ethylene copolymers preferably constitute at least about 90, preferably 96 to 99.7 weight percent polymerized ethylene units and 0.3 to 4 weight percent comonomer. Propylene, 1-butene, 1-pentene, 1-hexene, and 1-octene are especially preferred comonomers.
The polymers can be prepared from the catalyst of this invention by solution polymerization, slurry polymerization, and gas phase polymerization techniques using conventional equipment and contacting processes. Contacting of the monomer or monomers with the catalyst can be effected by any manner known in the art of solid catalysts. One convenient method is to suspend the catalyst in an organic medium and to agitate the mixture to maintain the catalyst in suspension throughout the polymerization process. Other known contacting methods such as fluidized bed, gravitating bed, and fixed bed can also be employed.
The catalysts of this invention are particularly suitable for use in slurry polymerization systems to produce a complete spectrum of polymers so far as melt flow is concerned, utilizing a single catalyst. Everything from blow molding grade resins which may require a melt index of as little as 0.1 or less to paper coating and injection molding grade resins which may require a melt flow of 20 or greater can be produced from a single catalyst system simply by the use of a molecular weight control agent, such as hydrogen. While hydrogen is known as a molecular weight control agent, the catalyst of this invention displays an extraordinary sensitivity to hydrogen so that by controlling the amount of hydrogen utilized, polymers having a very high molecular weight as indicated by low melt flow, though polymers having a very low molecular weight as indicated by high melt flow can be obtained. Further control of melt flow can be obtained by the small amount of leeway in temperature control and by the known effect of higher catalyst activation temperature causing the melt flow of the resulting polymer to be higher. However, yet a further advantage of this invention is that a single activation temperature for the catalyst and a single polymerization temperature can be utilized and still obtain a broad spectrum of polymers utilizing a single catalyst. By "spectrum of polymers", it is meant that that catalyst can be used to produce a low flow polymer one time. Then another time, the same type of catalyst can be used to produce a high flow polymer or anything in between by adjusting other variables such as temperature and amount of hydrogen.
With slurry polymerization of ethylene and predominantly ethylene copolymer systems, the conventional temperature range is generally about 200.degree.-230.degree. F. (93.degree.-110.degree. C.) and the commercial systems are generally run as close to the maximum (i.e., the point polymer goes into solution) as possible, i.e. 225.degree. F..+-.5.degree. F. (107.degree. C..+-.3.degree. C.) in order to get the highest possible melt index. The catalyst of this invention allows running at the low end of the conventional temperature range, i.e. 205.degree. F..+-.5.degree. F. (96.degree. C..+-.3.degree. C.) in systems normally employing 225.degree. F. (107.degree. C.). The lower temperature gives a relatively higher monomer partial pressure, thus giving higher activity.
Catalysts of this invention have the further advantage of not having any noticeable induction time between initial contact with the monomer and the initiation of polymerization.
When hydrogen is used in the prior art, it is generally used at partial pressures up to 120 psia (0.8 MPa), preferably within the range of 20 to 70 psia (0.01 to 0.48 MPa). Similar amounts are used in accordance with this invention, although because of the high sensitivity to hydrogen, it is possible to use smaller amounts, for instance 10 to 70 psia.
The tendency of the catalysts of this invention to produce higher melt flow polymers when hydrogen is utilized corresponds to the tendency of other catalyst systems to produce higher melt flow polymers when hydrogen is utilized, the difference being that the catalyst of this invention is extraordinarily sensitive to the effects of hydrogen. However, in other areas, the catalysts of this invention act in a manner different from the prior art catalysts and these differences are in a beneficial direction. For instance, boron cocatalysts sometimes used in the prior art are used in spite of the fact that they tend to have an adverse effect on melt flow, i.e., cause the melt flow to drop. However, the boron cocatalysts of this invention substantially increase the melt flow, while boron in the phosphate support of this invention lowers melt flow, thus giving a unique opportunity to control melt flow and related polymerization conditions.
Further, there are known relationships between the density of a polymer of a particular monomer and the resulting properties such as stress crack resistance and flexural modulus. The polymers of the prior art generally represent a compromise between competing properties, for instance, in the use of a small amount of comonomer in ethylene polymers to produce a polymer with greater stress crack resistance but one which has a concomitant decrease in flexural modulus. Unaccountably, the polymers produced by the catalysts of this invention have densities (and the corresponding higher flexural moduli associated therewith) in excess of what would be predicted for a given monomer and at the same time exhibit a whole order of magnitude greater stress cracking resistance than would be expected based on the performance of similar prior art olefin polymers. This increase in density also is the inverse of what occurs in prior art catalyst systems using boron cocatalysts since boron cocatalysts normally decrease density. These novel and beneficial properties are all the more remarkable because infrared analysis of the polymer does not indicate any difference between the novel polymers of this invention and conventionally produced olefin polymers.
It is known in the art that the presence of a comonomer in ethylene polymerization may increase the melt flow of the resulting polymer. However, with the catalyst of this invention this effect is unexpectedly magnified, with only small amounts of comonomer giving major increases in melt flow of the resulting polymer. The difference is one of a kind rather than degree such that it is actually feasible to use comonomer addition as a method of controlling melt flow.
This is particularly feasible because of the other peculiar characteristic of the cocatalysts of this invention to give high density polymer. Thus even with some comonomer to raise melt flow, the density and flexural modulus are still high. Suitable amounts of comonomer for this purpose can vary widely particularly if the object is to produce a copolymer. If the object is to produce a polymer which is essentially a homopolymer, 0.001 to 0.3, preferably 0.01 to 0.1 mole percent comonomer based on the moles of ethylene in the feed can be used. If the object is to produce a copolymer, 0.5 to 20 mole percent or more can be used although enough to give 0.4 to 3 weight percent incorporation based on the weight of all monomers is preferred. Preferred comonomers for predominantly ethylene homopolymers are at least one of propylene, 1-butene, 1-pentene, 1-hexene and 1-octene. Polymers having a melt index of greater than 0.1 can easily be produced in this way in a slurry system.
Another area in which the prior art olefin polymers always represent a compromise in properties is with regard to shear response. For certain applications, a high shear response as evidenced by the ratio of high load melt index to melt index, is desirable. This has heretofore been associated with broad molecular weight distribution as determined by size exclusion chromatography, for instance. Unexpectedly the polymers produced by the catalysts of this invention exhibit high shear response as evidenced by high HLMI/MI ratios indicating extremely broad molecular weight distribution. However, the size exclusion chromatography analyses indicate a far narrower M.sub.w /M.sub.n than would be expected for a given HLMI/MI ratio. The molecular weight distribution or heterogeneity index is indicated by the ratio of the weight average molecular weight (M.sub.w) to the number average (M.sub.n). In this regard, it must be kept in mind that HLMI/MI ratios are meaningful only if compared on a comparable melt index basis. The references herein to melt index (MI) refer to ASTM D1238-65T, Condition E, and to high load melt index (HLMI) refer to ASTM D1238-65T, Condition F, the difference being 21,600 gram weight in the high load test and a 2,160 gram weight in the regular melt index test, the temperature being 190.degree. C. in each instance when the tests are utilized for predominantly ethylene polymers and copolymers. FIGS. 4 and 5 visually depict this novel property.
The following table demonstrates the relationship between melt index, HLMI/MI ratio, and M.sub.w /M.sub.n as determined by size exclusion chromatography for a number of actual runs made in accordance with the invention. For comparison, a polymer produced by prior art silica supported chromium oxide catalysts having a melt index of 0.1 to 0.5 has an HLMI/MI ratio of about 100 and a M.sub.w /M.sub.n of about 12 for a HLMI/MI to M.sub.w /M.sub.n ratio of about 8 which contrasts with the ratio of 17-31 for the polymers of the invention in the melt index range between 0.1 and 0.5. Thus within this MI range novel polymers having a ratio of greater than 15 are common using the catalyst system of this invention.
TABLE A ______________________________________ MW DISTRIBUTION MI ##STR1## Mw/Mn to Mw/MnRatio of HLMI/MI ______________________________________ 30.1 43 4.6 9.3 19.8 39 5.5 7.1 17.8 47 7.5 6.3 12.0 51 6.3 8.1 3.8 115 11.0 10.5 1.5 118 15.3 7.7 0.63 246 20.9 11.8 0.60 210 20.9 10.0 0.43 375 12.1 31.0 0.23 461 17.0 27.0 0.13 386 23.0 17.0 0.12 346 16.7 21.0 0.14 405 22.2 18.0 0.17 641 25.0 26.0 ______________________________________
Table B demonstrates the relationship between density and P/Al atom ratio for ethylene homopolymerization using a chromium catalyst on an aluminum phosphate base activated at 500.degree. C. The density was determined by the standard density gradient column method (ASTM D 1505-68). TEB stands for triethylborane.
TABLE B ______________________________________ DENSITY AND P/Al ATOM RATIO Melt Flow Density ______________________________________ P/Al = 0.8 Alone 0 HLMI 0.9622 H.sub.2 0.31 MI 0.9651 TEB 0.43 MI 0.9716 TEB + H.sub.2 16.2 MI 0.9722 P/Al = 0.2 Alone 0.1 HLMI 0.9543 TEB 0.1 HLMI 0.9579 TEB + H.sub.2 0.4 MI 0.9626 ______________________________________
As can be seen densities in excess of 0.965 for unannealed polymer are possible with the catalyst of this invention. While the art sometimes broadly alludes to polyethylene densities above 0.965 and such can be obtained by annealing, the fact is that the densities produced with the catalyst of this invention for a given set of conditions are higher than can be produced with prior art chromium or titanium catalyst systems.
Table C demonstrates the relationship of density and ESCR for ethylene homopolymers produced using catalysts of this invention.
TABLE C ______________________________________ ESCR AND FLEXURAL MODULUS Flexural Modulus.sup.(3) P/Al Temp. Add. MI Den..sup.(1) ESCR.sup.(2) MPa psi ______________________________________ 0.2 500.degree. C. H.sub.2 + 0.10 0.9626 428 1458 211,500 TEB 0.4 300.degree. C. H.sub.2 0.11 0.9636 214 1497 217,100 0.4 300.degree. C. H.sub.2 + 0.37 0.9666 82 1604 232,600 TEB 0.8 300.degree. C. TEB 0.60 0.9701 181 1519 220,300 0.8 500.degree. C. H.sub.2 0.23 0.9629 47 1656 240,200 1.0 500.degree. C. H.sub.2 0.30 0.9651 47 1657 240,300 1.0 500.degree. C. TEB 0.43 0.9710 -- 1869 271,100 1.0 700.degree. C. TEB 2.5 0.9727 -- 2020 293,000 ______________________________________ .sup.(1) ASTM D 150568. .sup.(2) ASTM D 169370, Condition A (50.degree. C.), Environmental Stress Crack Resistance. .sup.(3) Flexural Modulus ASTM D 79066.
Ethylene homopolymers of the prior art normally have an environmental stress crack resistance at a nominal 0.1 MI of less than 30 hours. As can be seen, the invention polymers have an ESCR as much as an order of magnitude higher than would be expected and with higher, not lower stiffness. It is known in the prior art to feed pure ethylene to a reactor using a catalyst which oligomerizes some of the ethylene to 1-butene or other comonomers and thus get a polymer of good ESCR but such polymer has the low density and poor (low) flexural modulus normally associated with copolymers. This novel property of the polymers of this invention is visually depicted in FIG. 3 which shows the relationship between environmental stress crack resistance (ESCR) and modulus for commercial high density olefin polymers and the novel type of polymers produced by the catalyst of this invention. In all instances, the melt index is in the 0.1 to 0.9 range so the comparison is on a fair basis.EXAMPLE I--CATALYST PREPARATION
The catalysts were prepared in three general methods and variations thereof.
In method A (the first method broadly described hereinabove), about 0.5 mole of Al(NO.sub.3).sub.3.9H.sub.2 O was dissolved in about 500 mL of deionized water and to it was added sufficient 85% H.sub.3 PO.sub.4 to give the desired atomic ratio of P:Al. The resulting solution was neutralized by adding sufficient concentrated ammonium hydroxide to reach a pH of about 6-7. The white hydrogel precipitate was filtered off and washed with about 3 L of deionized water. The filter cake was dried in procedure (1) by simply placing it in a vacuum oven at about 80.degree. C. for a few hours. In a preferred procedure (2) the filter cake was dried of water by employing azeotropic distillation or washing with isoamyl alcohol to remove the water. Each product after removal of water was impregnated with a solution of chromium(III) acetate dissolved in an alkanol, such as methyl alcohol, sufficient to provide about 1 weight percent chromium based on the dry finished catalyst. Afterward the filter cake was dried of alcohol by heating at 60.degree. C. in a vacuum to remove the alcohol. Each catalyst was activated for polymerization by calcining it in a fluidized bed with dry air for about 5 hours or more at the specified temperature.
When a boron-aluminum phosphate gel is desired a suitable amount of a soluble borate such as ammonium borate or boric acid can be included with the aluminum salt. It is convenient to employ a commercially available compound combining both aluminum and boron such as Al(OH).sub.2 OC.sub.2 H.sub.5.1/3H.sub.3 BO.sub.3 in place of the aluminum nitrate.
Also, in place of or in admixture with the H.sub.3 PO.sub.4, ammonium phosphates such as NH.sub.4 H.sub.2 PO.sub.4 and (NH.sub.4).sub.2 HPO.sub.4 can be used alone or mixtures thereof to furnish the desired amount of phosphate ions required to make the metal phosphate gels.
Another soluble aluminum salt such as aluminum acetate or sulfate can be substituted for the nitrate, if desired. Less preferable soluble aluminum salts such as the chloride can also be employed but the gels may require more thorough washing to remove most of the chloride anions.
Method B (the second method broadly described hereinabove) is a substantially anhydrous method. To a solution containing about 1/8 mole of aluminum triisoproxide (or related alkoxide) dissolved in about 400 mL of dry isopropyl alcohol, for example, was added a solution containing about 200 mL of dry isopropyl alcohol, a little deionized water, e.g. 0.2 mole, and sufficient 85% H.sub.3 PO.sub.4 to give the desired atomic ratio of P:Al. For example, with about 6.5 mL of 85% H.sub.3 PO.sub.4 (0.095 mole), the P:Al atomic ratio is about 0.76:1. The resulting precipitate was isolated by filtering and the filter cake is dried in a vacuum oven at about 80.degree. C. The dry product was then impregnated anhydrously by contact with a methanol solution of chromium(III) acetate sufficient to provide about 1 weight percent chromium based on the dry, finished catalyst. The catalyst was activated by heating for the desired length of time, e.g. five hours, at the specified temperature in a fluidized bed in dry air. Method B is different in principle from methods A and C in that the gel forms on addition of the phosphoric acid.
Method C (the third method broadly described hereinabove) is presently preferred. It was generally carried out by heating the desired quantity of an aluminum salt such as Al(NO.sub.3).sub.3.9H.sub.2 O, e.g., about 1 lb. (454 g), to about 80.degree. C. to form a melt. The desired quantity of an ammonium phosphate, e.g., NH.sub.4 H.sub.2 PO.sub.4, was dissolved in the melt to provide the atomic ratio of P/Al needed, and finally the desired amount of chromium(III) acetate or chromium (III) nitrate was added to the melt mixture to provide about 1 weight percent chromium based on the weight of the dry, finished catalyst. Sufficient concentrated NH.sub.4 OH, e.g., 30 weight percent NH.sub.3, was mixed with the melt mixture to neutralize it giving a pH of about 6-7. The resulting mixture was washed with sufficient deionized water to remove substantially all of the ammonium nitrate by-product and the washed product in turn was washed with isopropyl alcohol or other volatile water-miscible organic liquid to displace the water or azeotrope dried. The resulting product can be further dried in a vacuum oven, if desired, and activated as before in a fluidized bed in dry air for about 5 hours at the specified temperature. As with the first method (Method A), boric acid or a soluble borate such as ammonium borate can be included with the reactants prior to gellation.
In the catalyst preparation of Method C, the melt containing the Al(NO.sub.3).sub.3.9H.sub.2 O, the NH.sub.4 H.sub.2 PO.sub.4 and the Cr(NO.sub.3).sub.3.9H.sub.2 O can be treated with NH.sub.4 OH to obtain a pH of about 6-7 to form the gel and the gel dried in the presence of the by-product NH.sub.4 NO.sub.3. While this is essentially a non-aqueous system, there is a small amount of water present such that a sheet of pH indicator paper can be pressed into the gel and a pH reading obtained. The dry product can then be cautiously calcined to obtain the final catalyst. This procedure must be done carefully to avoid potential explosions or other undesired reactions.
Method C is fundamentally different from Methods A and B in that no solvent is used.EXAMPLE II--ETHYLENE POLYMERIZATION
Each run was conducted in a clean, dry, air-free, stirred, stainless steel reactor of about a 2 L capacity. About 600 g of isobutane was used in each run as diluent with a catalyst charge ranging from about 0.03 to about 0.8 g. The reactor and its contents were heated to the desired operating temperature, ethylene was pressured in to give about 565 psia (3.9 MPa), and the run was started immediately as the catalysts, unlike the corresponding chromium oxide-silica catalysts, do not have an induction period. Ethylene pressure was maintained during the run by supplying additional ethylene as required from a reservoir. When used, the triethylborane (TEB) was added to the reactor as a solution of 1 weight percent in n-heptane.
Each run was terminated by stopping the ethylene flow and venting the gaseous reactor contents to a flare line for disposal. The polymer was recovered, dried and weighed to determine catalyst productivity which is expressed in terms of grams polyethylene per gram catalyst.
The physical properties of each polymer, in this and subsequent examples, when given, were determined in accordance with the following ASTM test procedures.
______________________________________ Melt index (MI) ASTM D 1238-65T, Condition E. High load melt index (HLMI) ASTM D 1238-65T, Condition F. Density, g/cc ASTM D 1505-68. ______________________________________
The HLMI/MI ratio is thought to give an indication of the polymer molecular weight distribution or shear response. As the ratio increases, the molecular weight distribution is also thought to increase.
The heterogeneity index (HI) is thought to provide a more accurate representation of polymer molecular weight distribution. As the ratio increases, the molecular weight distribution is thought to broaden. HI is determined from the weight average and number average molecular weight values obtained from size exclusion chromatography.
Ethylene polymerization was carried out with samples of the catalysts activated at different temperatures and the results are summarized in Table I.
TABLE I __________________________________________________________________________ Effect of Alkyl Boron Cocatalyst Act. Run Run Temp. Temp. Prod. Time HLMI/ No. Prep. P/Al .degree.C. Add. .degree.F. g/g min. MI MI __________________________________________________________________________ 1 Aq-Az.sup.(1) 1.0 500 None 205 1725 90 0 (.74 H).sup.(6) -- 2 8 ppm TEB (96.degree. C.) 3565 65 .43 375 3 H.sub.2 1400 90 .30 152 4 8 ppm TEB + H.sub.2 2515 50 11.4 57 5 Aq-OD.sup.(2) 0.9 700 None 225 605 90 0 (.86 H) -- 6 8 ppm TEB (107.degree. C.) 509 60 1.2 144 7 H.sub.2 427 100 0.95 104 8 8 ppm TEB + H.sub.2 605 90 32 47 9 Melt-Az.sup.(3) .8 700 None 205 3844 60 0 (.76 H) -- 10 4 ppm TEB (96.degree. C.) 9420 60 1.41 122 11 4 ppm TEB + H.sub.2 5340 60 6.8 64 12 Melt-Az.sup.(3) .8 500 None 205 3135 60 0 (.37 H) -- 13 4 ppm TEB (96.degree. C.) 5440 60 .51 143 14 4 ppm TEB + H.sub.2 5605 60 3.15 73 15 Melt-OD.sup.(4) .8 600 4 ppm TEB 205 3010 90 .03 533 (96.degree. C.) 16 Melt-Az.sup.(5) .8 600 4 ppm TEB 205 2230 60 .04 511 (96.degree. C.) __________________________________________________________________________ .sup.(1) Method A with drying method (2), i.e. aqueous precipitation and azeotrope drying. .sup.(2) Method A with drying method (1), i.e. aqueous precipitation and oven drying. .sup.(3) Method C, i.e. hydrogel formed from melt but then water added to wash followed by azeotropic drying. .sup.(4) Hydrogel formed from melt but water added to wash followed by oven drying, i.e. also a concentrated mass during gellation. In this run, 469 grams (1.25 mole) of Al(NO.sub.3).sub.3.9H.sub.2 O and 3.48 grams boric acid were used with sufficient monobasic ammonium phosphate to give the Al/P ratio of 0.8. Some water (125 mL) was in the melt and the melt was dripped into concentrated ammonium hydroxide. .sup.(5) Like (4) except washed in alcohol and the alcohol removed in a vacuum oven. While the productivity is not outstanding in this run, other runs gave better overall results. One other run similar to this except without boric acid and using aluminum sulfate instead of aluminum nitrate gave 32 cc grams polymer per gram of catalyst in 25 minutes. .sup.(6) "H" indicates HLMI.
In the first series, Runs 1 and 3 are control runs. A comparison of 1 and 2 shows the dual benefit in productivity and melt flow from the triethylborane (TEB) cocatalyst. A comparison of Runs 2, 3 and 4 shows how much more effective in increasing melt flow hydrogen is with a catalyst of this invention as compared with a prior art catalyst.
Runs 5-8 show the same effect of the boron-containing cocatalyst at a different P/Al ratio, different activation temperature, and different polymerization temperature, Runs 5 and 7 being control runs.
Run 9 is a comparative control run for the third series relative to Runs 10 and 11 to show the same effect of the boron-containing cocatalyst in a catalyst produced by Method C. Run 9 on an absolute basis is an invention run since it shows the phosphate base produced from a melt gives high productivity, i.e. 3844 versus 1725 in Run 1. While part of this difference may be due to changes in other variables, the advantage for the melt gellation has been shown by other runs.
In the fourth series, Runs 13-14 show the same effect of the boron-containing cocatalyst at a different catalyst activation temperature as compared with comparative Control Run 12.
Invention Runs 15-16 show improved productivity compared with Control Run 1. Also while the melt index is slightly higher (a barely measurable amount using the regular melt index test compared with 0), these runs show that compared with Runs 10, 11, 13 and 14, the melt index is lower. This would allow higher activation temperature (to get higher activity) if desired.EXAMPLE III
A series of polymerization runs was made in the reactor at 96.degree. C. for 1 hour in the manner described before using a catalyst prepared as described in Method B and a metal alkyl adjuvant. The P:Al atomic ratio was 0.8:1 and each catalyst was activated at 500.degree. C. for 5 hours in dry air under fluidizing conditions.
The concentration of metal alkyl is expressed in ppm based on the weight of diluent contained in the reactor.
Hydrogen, when used, was generally introduced to the reactor containing the desired ethylene pressure to provide 50 psi (0.34 MPa) partial pressure. The total pressure in each run was about 565 psia.
The results obtained are given in Table II.
TABLE II __________________________________________________________________________ Effect Of Metal Alkyl Adjuvant, Catalyst On Polymer Melt Index Metal Alkyl.sup.(a) No.Run ppmConcentration Type MI ##STR2## g/g cat/hrProductivity Remarks __________________________________________________________________________ 17 0 None 0 (0.2 H) .sup.(b) 1725 Control 18 8 BEtCl.sub.2 0.10 250 505 19 8 BEt.sub.2 OEt 0.69 144 1200 20 8 DEAC 0 (0.6 H) -- 1450 21 4 DEAC 0.10 204 1190 H.sub.2 also used 22 8 DEALE 0 (0.5 H) -- 1160 23 8 DEZ 0.10 156 1245 H.sub.2 also used 24 8 EADC 0 (0.6 H) -- 1065 25 8 EADC 0.03 526 1100 H.sub.2 also used 26 8 LiBu 0.01 606 1240 27 2 LiBu 0.09 211 980 H.sub.2 also used 28 8 MgBu.sub.2 0.13 185 1170 H.sub.2 also used 29 4 TEA 0 (0.2 H) -- 1885 30 8 TEA 0 (1.4 H) -- 1720 31 8 TEA 0.23 167 1055 H.sub.2 also used 32 4 TEB 0.11 375 3820 33 8 TEB 0.76 190 2135 34 16 TEB 0.61 270 1930 35 4 TEB 5.5 75 3225 H.sub.2 also used __________________________________________________________________________ .sup.(a) Abbreviations used BEtCl.sub.2 ethyldichloroborane BEt.sub.2 OEt diethylboron ethoxide DEAC diethylaluminum chloride DEALE diethylaluminum ethoxide DEZ diethylzinc EADC ethylaluminum dichloride LiBu nbutyllithium MgBu.sub.2 din-butylmagnesium TEA triethylaluminum TEB triethylborane .sup.(b) A dash signifies not applicable. H under MI heading is HLMI.
Inspection of the data given in Table II reveals that of the metal alkyls tested, only the boron compounds cooperate with the catalyst in yielding polymers having substantially higher melt index values than that of comparative control run 17. A comparison of runs 32 (no H.sub.2) and 35 (H.sub.2) shows that when hydrogen and triethylborane are both present the combination gives unexpectedly high melt index response and good productivity, e.g., with 4 ppm TEB, the polymer melt index is 0.11 and productivity is 3820 g polymer per g catalyst and with 4 ppm TEB plus hydrogen, the polymer melt index is 5.5 and productivity is 3225 g polymer per g catalyst. Other non-boron-containing cocatalysts which were tried and found not to produce any MI improvement over that of Control Run 17 were tributyl antimony, triphenyl antimony, tetrabutyl tin, and tributyl tin (Sn.sub.2 Bu.sub.6).
These data show: (1) a variety of boron-containing cocatalysts gave higher melt index, and (2) none of the non-boron-containing cocatalysts tried gave significantly higher melt index. The trialkylborane-containing cocatalysts worked best giving both higher melt index and greater productivity. One boron-containing cocatalyst was tried which had little or no beneficial effect. This was sodium tetraphenylborate. Two others, lithium tetrabutylborate and triphenylborane had only a slight beneficial effect.EXAMPLE IV
Another series of catalysts having a calculated atomic ratio of P/Al of about 1, some prepared in the presence of a borate, were made by employing catalyst preparation Method A. The catalysts containing AlPO.sub.4 alone were made by precipitating an aqueous solution containing aluminum nitrate and diammonium hydrogen phosphate with aqueous ammonium hydroxide to a final pH of about 6-7. The precipitate was washed with hot water, oven dried (conventional preparation method) and impregnated with an aqueous solution of CrO.sub.3 sufficient to provide 1 weight percent chromium on the finished catalyst.
The catalysts made with aluminum and boron prepared by contacting an aqueous solution containing 140 g of Al(OH).sub.2 OC.sub.2 H.sub.5.1/3H.sub.3 BO.sub.3 with a water solution containing 132 g of (NH.sub.4).sub.2 HPO.sub.4 to obtain a stiff, white precipitate. The precipitate was filtered, the cake washed with water and then dried by azeotropic distillation with isoamyl alcohol. This drying was done under mild conditions, i.e. at room temperature up to the boiling point of the azeotrope. With isoamyl alcohol which boils at 136.degree. C., the azeotrope boils at about 95.degree. C. so the drying takes place mainly at 95.degree. C. but creeps up to 135.degree. C. at the end. With isopropyl alcohol the mixture is just warmed slightly, i.e. up to about 60.degree. C. The product was dried at 150.degree. C. in nitrogen and then impregnated with a solution containing chromium(III) acetate dissolved in methyl alcohol sufficient to provide 1 weight percent chromium based on the final catalyst.
Individual portions of the catalyst samples were then activated at the indicated temperatures and times.
Analysis of the finished catalysts showed the actual P/Al atomic ratios to be about 0.95:1.
The catalysts were employed in ethylene polymerization as before. In some runs, 50 psi hydrogen was present, in some runs 4 ppm TEB was present and in some runs both 50 psi hydrogen and 4 ppm TEB were present. All of the AlPO.sub.4 bases were oven dried and the polymerization carried out at 225.degree. F. All of the AlPO.sub.4 -BPO.sub.4 bases were azeotrope dried and the polymerizations carried out at 205.degree. F.
The results are presented in Table III, runs 36-47.
An AlPO.sub.4 -BPO.sub.4 base was prepared utilizing 469 grams of Al(NO.sub.3).sub.3.9H.sub.2 O plus 3.9 grams of boric acid, 11.5 grams Cr(NO.sub.3).sub.3.9H.sub.2 O, 115 grams monobasic ammonium phosphate and 125 mL of water. One part of this melt was diluted with one-half part of water and the resulting concentrated mass dripped into concentrated ammonium hydroxide. The resulting gel was washed twice with water and then with alcohol. This is et out in Table III hereinbelow as run A. Run B hereinbelow is identical except the dilution was 1:1. The above procedure was repeated except titanyl sulfate was substituted for the boric acid so as to give 5 mole percent titanium instead of 5 mole percent boron and a small amount of hydrogen peroxide was utilized in order to dissolve the titanyl sulfate. This is set out hereinbelow as run C. Run D set out hereinbelow is identical to run C except 7.5 mole percent titanium was used in place of the 5 mole percent boron.
TABLE III __________________________________________________________________________ Ethylene Polymerization, AlPO.sub.4 --BPO.sub.4 Support Catalyst Run No.Run Gel Base Temp. .degree.C.Activation HoursTime Min.Time, MI HLMI ##STR3## g/g cat/hrProductivity Remarks SystemAdjuvant __________________________________________________________________________ 36 AlPO.sub.4 500 16 90 0 2.0 -- 382 Control None 37 AlPO.sub.4 --BPO.sub.4 500 5 90 0 0.96 -- 1960 Invention None 38 AlPO.sub.4 400 16 73 0 16 -- 205 Control None 39 AlPO.sub.4 --BPO.sub.4 300 5 81 0 3.9 -- 796 Invention None 40 AlPO.sub.4 --BPO.sub.4 300 5 90 0.65 80 123 1150 Invention TEB 41 AlPO.sub.4 --BPO.sub.4 500 5 50 12 756 63 2195 Invention H.sub.2 + TEB 42 AlPO.sub.4 700 15 90 0 0.86 -- 605 Control None 43 AlPO.sub.4 --BPO.sub.4 700 5 90 0 0.58 -- 2500 Invention None 44 AlPO.sub.4 700 15 60 1.2 173 144 509 Invention TEB 45 AlPO.sub.4 --BPO.sub.4 700 5 60 2.5 230 92 2820 Invention TEB 46 AlPO.sub.4 700 15 90 32 1504 47 605 Invention H.sub.2 + TEB 47 AlPO.sub.4 --BPO.sub.4 700 5 40 16 768 48 1945 Invention H.sub.2 + TEB A AlPO.sub.4 --BPO.sub.4 600 3-5 60 0 11.4 -- 2475 Invention 4 ppm TEB B AlPO.sub.4 --BPO.sub.4 600 3-5 40 .02 10.0 498 4898 Invention 4 ppm TEB C AlPO.sub.4 --Ti 600 3-5 60 0.19 47.7 251 2970 Control 4 ppm TEB D AlPO.sub.4 --Ti 600 3-5 60 0.08 24 300 1910 Control 4 ppm __________________________________________________________________________ TEB
The results show that when the factors which affect productivity are constant there is often an increase in productivity due to the presence of the boron. These data show a decrease in melt index which allows operating at a higher polymerization temperature. In addition the presence of the boron in the support consistently allows control of the MI downward which is sometimes desired because of the inherent ability of the catalysts of this invention to increase MI. The beneficial effects of TEB alone or in conjunction with hydrogen are evident with catalysts derived from AlPO.sub.4 -BPO.sub.4 gels as well as the AlPO.sub.4 gels. Based on productivity alone, runs 44 and 46 are no better than the controls. However, the melt index response shows that the presence of TEB alone or with TEB+hydrogen gives an unexpected result even with conventional aluminum phosphate base preparation, hence these are invention runs.EXAMPLE V
A series of gels in which the atomic ratio of P/Al was varied from 0 to 1.2 was prepared by employing Method A and procedure (2) azeotrope drying, for drying the gels. As before, each gel was impregnated with a solution of chromium(III) acetate dissolved in methyl alcohol sufficient to provide about 1 weight percent chromium based on the dry finished catalyst. As before, each catalyst was activated for polymerization by calcination in a fluidized bed with dry air for about 5 hours at the specified temperature.
Each catalyst was tested for ethylene polymerization as before at 96.degree. C. with 4 ppm TEB in one series and with 4 ppm TEB plus 50 psia (0.34 MPa) hydrogen in a second series.
The melt flows of the produced polymers are given in Table IV.
TABLE IV __________________________________________________________________________ Melt Index Response vs. Catalyst Calcining Temperature With TEB and TEB Plus Hydrogen TEB TEB + Hydrogen Cata- Run Base Atom Catalyst Calcining Temp. .degree.C. Run lyst Calcining Temp. .degree.C. No. Ratio, P/Al 300 500 700 No. 300 500 700 __________________________________________________________________________ 52 0 dead 0 0 59 dead dead 0.05 53 0.2 0 0 (0.1 HLMI) 0.3 60 0 (12 HLMI) 0.1 0.4 54 0.4 0 (3 HLMI) 0 (5 HLMI) 0.1 61 0.4 1.2 3.8 55 0.6 0 (8 HLMI) 0.14 0.6 62 1.5 3.4 11.5 56 0.8 0.6 1.2 0.5 63 4.6 16 18.6 57 1.0 0.5 0.4 0.6 64 10.6 11.4 17.8 58 1.2 dead dead 0.4 65 dead dead dead __________________________________________________________________________
The data presented in Table IV show several trends. Catalysts in which the P/Al atom ratio is zero showed poor activity. Similarly, catalysts with a P/Al atom ratio of 1.2 are generally inactive, with the single exception shown in run 58. Thus, active catalysts with good melt index potential, e.g. about 0.1 MI or higher, have atom ratios of P/Al ranging from about 0.2:1 to about 1:1.
The calcining temperature is also seen to be one determining factor in the melt index performance of the catalysts. Thus, as the calcining temperature increases from about 300.degree. to about 700.degree. C., the melt index performance generally increases over the preferred P/Al range noted above. This is visually depicted in FIG. 2.
As noted before, the melt index potential of the catalysts is particularly improved when TEB and hydrogen is employed in the polymerization.EXAMPLE VI
A series of aluminum phosphate gels was prepared by employing Method C and several variations thereof as shown below in which a melt was formed from 94 g (0.25 mole) of Al(NO.sub.3).sub.3.9H.sub.2 O, 23 g (0.2 mole) of NH.sub.4 H.sub.2 PO.sub.4, and 2.4 g (0.006 mole) of CR(NO.sub.3).sub.3.9H.sub.2 O by application of gentle heat to give a volume of about 100 mL at a temperature of about 80.degree. C. The calculated P/Al atomic ratio is about 0.8:1. To the melt was added with vigorous stirring, 46 mL (0.72 mole NH.sub.3) of concentrated NH.sub.4 OH (30 weight percent NH.sub.3). The reaction mass at a pH of about 6-7 set to a hard gel, which was thoroughly washed with hot, deionized water and the washed product divided in two approximately equal portions. Portion 1 (catalyst 1 base or support) was dried overnight (about 15 hours) in a vacuum oven at 80.degree. C. Portion 2 (catalyst 2 base) was dried of water by azeotrope distillation with isoamyl alcohol and then the alcohol removed by heating at 60.degree. C. in a vacuum oven.
Catalyst 3 base was prepared in the manner used for catalyst 2 base except that in the gelling step the 100 mL of melt was diluted to 200 mL with water (100 mL water) and to it was added 46 mL of concentrated NH.sub.4 OH.
Catalyst 4 base was prepared in the manner used for catalyst 2 base except that in the gelling step the 100 mL of melt was diluted to 400 mL with water (300 mL of water) and to it was added 46 mL of concentrated NH.sub.4 OH.
Catalyst 5 base was prepared in the manner used for catalyst 2 base except that gelling occurred before all the ammonium hydroxide solution was added. The pH was about 3-4 at this stage and the gel was washed and dried as for catalyst 2 base. This shows that the pH during gelling should be about 5 or above.
Catalyst 6 base was prepared by gelling 100 mL of the melt with 46 mL of concentrated ammonium hydroxide as described at the beginning of this Example. The resulting gel was dried overnight in a vacuum oven at 80.degree. C. without removal of the salt by-product.
Catalyst 7 base was prepared in the manner used for catalyst 2 base except that in the gelling step the 100 mL of melt was gelled with a solution of 46 mL of NH.sub.4 OH diluted to 100 mL.
A portion of each catalyst base was then activated at 500.degree. C. for 5 hours as before. The surface areas of the recovered, activated catalysts were then determined by the B.E.T. nitrogen sorption method as known in the art.
A portion of each catalyst was tested in ethylene polymerization at 96.degree. C. using 4 ppm TEB as adjuvant in each run.
The surface area of each catalyst and its productivity in terms of grams polymer per g catalyst per hour are given in Table V.
TABLE V __________________________________________________________________________ Ethylene Polymerization With Melt Derived Catalysts Catalyst Pore Run Catalyst Surface Volume, Productivity No. Base Area, m.sup.2 /g cc/g g/g cat/hr Remarks __________________________________________________________________________ 66 1 Invention 330-380.sup.(a) 0.60 2540 washed, oven dried 67 2 Invention 330-380.sup.(a) 0.84 3955 washed, azeotrope dried 68 3 Comparative 254 0.73 3540 diluted before Control gelling 69 4 Comparative 223 0.39 3020 diluted before Control gelling 70 5 Control 493 0.51 dead gel at acid pH 71 6 Invention 330-380.sup.(a) 0.74 4160 unwashed, oven dried 72 7 Comparative 269 2485 diluted before Control gelling __________________________________________________________________________ .sup.(a) Estimated surface area based on similar preparations.
The data presented in Table V indicates that active ethylene polymerization catalysts are derived from melts containing salts of aluminum, chromium and ammonium phosphates that are subsequently gelled by enough ammonium hydroxide to insure that the pH of the mixture is about neutral, that is at least 5, preferably about 6-7. Generally, it will be at least 6. The poor results observed in run 70 shows that a catalyst derived from a gel precipitated at a moderate acid level (pH of about 3-4) yields an inactive catalyst. The good results shown in run 71 demonstrate that in preparing a catalyst base it is not necessary to remove the relatively large amounts of ammonium nitrate present in the gel when made as described. However, care must be exercised in the activation step to prevent or minimize any possible violent reaction that might occur due to the presence of the ammonium nitrate as it is heated.
The results given in run 67 demonstrate that a very active catalyst can be derived from a gel produced in the presence of relatively little water. The reason for this is thought to be that the more concentrated the gel the more physical strength it has. When the water content increases as in the preparation of the gels used in making the catalysts employed in runs 68, 69, and 72, then catalyst activity diminishes. Runs 68, 69 and 72 are labeled comparative control runs relative to runs 66, 67 and 71 to show the advantage for gelling in the melt in the absence of substantial amounts of water on an absolute basis. They are invention runs because they employ a borane cocatalyst.EXAMPLE VII
In all embodiments of this invention, a mixture of boron-containing cocatalyst as previously defined, preferably trihydrocarbylborane, more preferably trialkylboranes such as tributylborane, and a conventional cocatalyst such as an aluminum, zinc or magnesium alkyl can be used. Suitable aluminum alkyls are known in the art and include materials of the formula R.sub.3 Al, R.sub.2 AlX and RAlX.sub.2 and mixtures thereof wherein X is a bromine or chlorine, preferably chlorine and R is a 1 to 10 carbon hydrocarbyl radical, preferably a 2 to 4 carbon atom alkyl, most preferably ethyl. Triethylborane/triethylaluminum, tripropylborane/triethylaluminum and tributylborane/triethylaluminum are especially preferred combinations. Other suitable conventional cocatalysts are ZnR.sub.2 and MgR.sub.2 wherein R is as defined above.
The boron-containing cocatalyst tends to increase the melt flow whereas the other cocatalysts such as the aluminum alkyls do not. The mixture gives a compromise in melt flow as might be expected, but unexpectedly the mixture does not give a compromise on activity but rather the activity is as good or better than with the boron-containing cocatalyst alone.
Thus use of the mixture allows exceptional activity to be achieved and still allows control over melt index when a polymer having a lower melt index is desired. That is, with no cocatalyst, the activity and melt flow can be too low for a particular application. Use of the boron-containing cocatalyst will increase activity and melt flow which is good but may increase melt flow too much. Adding some of the aluminum cocatalyst allows retention of all of the activity increase (or even a further increase) while removing a part of the melt flow increase. The weight ratio of boron-containing cocatalyst to the other organo metal cocatalysts can vary from 1:10 to 10:1 but will generally be within the range of 3:1 to 1:3. This can be varied to give the exact melt flow desired without adversely affecting activity.
This is shown in Table VI.
TABLE VI ______________________________________ Run No. Additive Activity MI ______________________________________ 73 None 1725 .20 HLMI 74 4 ppm TEA 1885 .51 HLMI 75 8 ppm TEA 1720 1.35 HLMI 76 8 ppm TEA + H.sub.2 1055 .23 MI 77 4 ppm TEB 3820 .11 MI 78 4 ppm TEB + H.sub.2 3225 5.5 MI 79 None 1880 1.3 HLMI 80 4 ppm TEB + H.sub.2 2925 16.2 MI 81 4 ppm TEB + 4215 3.6 MI 4 ppm TEA + H.sub.2 ______________________________________
The aluminum phosphate base of runs 73-78 was made in accordance with Method B (i.e., using the aluminum isopropoxide). The P/Al ratio was 0.8 and the activation temperature was 500.degree. C. The chromium content was 1 weight percent. The aluminum phosphate base of runs 79-81 was made using method C, i.e., from melt and was activated at 700.degree. C. The P/Al ratio was 0.8 and the chromium content was 1 weight percent.
While this invention has been described in detail for the purpose of illustration, it is not to be construed as limited thereby but is intended to cover all changes and modifications within the spirit and scope thereof.
1. A polymer made of a monomer composition consisting essentially of ethylene having a ratio of HLMI/MI to M.sub.w /M.sub.n of greater than 15 and a melt index within the range of 0.1 to 0.5 produced using a catalyst system comprising a chromium catalyst on an aluminum phosphate-containing support in conjunction with a trialkylborane cocatalyst, said trialkylborane having alkyl groups having 2 to 5 carbon atoms per group.
2. A polymer according to claim 1 wherein said ratio is within the range of 17-31.
3. A thermoplastic polymer made of a monomer composition consisting essentially of ethylene having a relationship of environmental stress crack resistance to flexural modulus on or above curve B of FIG. 3 over a melt index range of 0.1 to 0.9, produced using a catalyst system comprising a chromium catalyst on an aluminum phosphate-containing support in conjunction with a trialkylborane cocatalyst, said trialkylborane having alkyl groups having 2 to 5 carbon atoms per group.
4. A polymer according to claim 1 wherein said trialkylboron cocatalyst used to prepare said polymer is triethylborane.
5. A polymer according to claim 3 further having a relationship of shear to melt index on or above curve C of FIG. 4.
6. A polymer according to claim 4 wherein said aluminum phosphate support is prepared by combining a molten aluminum salt with orthophosphoric acid and thereafter neutralizing to form aluminum orthophosphate having a phosphorus to aluminum atom ratio within the range of 0.2:1 to 1:1.
7. A polymer according to claim 6 wherein said chromium on said aluminum phosphate used to prepare said polymer is activated in air at a temperature within the range of 300.degree. to 800.degree. C.
8. A polymer according to claim 3 wherein said trialkylboron cocatalyst used to prepare said polymer is triethylborane.
9. A polymer according to claim 8 wherein said aluminum phosphate support is prepared by combining a molten aluminum salt with orthophosphoric acid and thereafter neutralizing to form aluminum orthophosphate having a phosphorus to aluminum atom ratio within the range of 0.2:1 to 1:1.
10. A polymer according to claim 9 wherein said chromium on said aluminum phosphate used to prepare said polymer is activated in air at a temperature within the range of 300.degree. to 800.degree. C.
11. A polymer according to claim 10 wherein said polymer has a melt index within the range of 0.1 to 0.5.
12. A polymer according to claim 11 wherein said polymer has a ratio of HLMI/MI to M.sub.w /M.sub.n of greater than 15.
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Type: Grant
Filed: Nov 7, 1983
Date of Patent: Mar 12, 1985
Assignee: Phillips Petroleum Company (Bartlesville, OK)
Inventors: Max P. McDaniel (Bartlesville, OK), Marvin M. Johnson (Bartlesville, OK)
Primary Examiner: Joseph L. Schofer
Assistant Examiner: Fred Teskin
Law Firm: French and Doescher
Application Number: 6/549,511
International Classification: C08F 444; C08F 424; C08F 462; C08F11002;


text:
Elevator / Escalator Accidents
If you've been injured in an elevator or on an escalator, the law firm of Norman M. Block, P.C. can help you recover compensation for your injuries.
Building owners are required to maintain their elevators and escalators in a safe condition. Mandatory periodic inspections are generally required by the municipality where the building is located. Building owners should keep a record of its own inspections and/or the inspections by an elevator or escalator maintenance company.
Common accidents in elevators and escalators include
- tripping when entering or exiting an elevator that is not level with the floor
- falling when an elevator or escalator suddenly stops or jerks
- falling when an escalator unexpectedly speeds up or slows down being struck by doors that close on the passenger
In general, the building owner must have had actual or constructive notice of a problem before it can be held liable for an elevator or escalator accident. In many situations, a legal doctrine known as "res ipsa loquitur" is enough to make the owner liable. Under this doctrine, if something happens that could not have occured but for the negligence of the building owner, the owner can be liable. The application of this doctrine is tricky and is best handled by an experienced law firm like Norman M. Block, P.C. Call us today if you've been injured in an elevator or on an escalator.

subset: commoncrawl


text:
Welltok publishes a seemingly premature press release announcing that it has raised $25 million of a planned $37 million Series D round. The round is being led by Bessemer Venture Partners, with no details provided on secondary investors. Welltok and BVP anticipate completing the fundraising by the end of the year. The new funding follows a February 2014 Series C that netted $22 million and brings the company's total funding to $73 million. That number will jump to $85 million if it is able to extend its Series D round all the way to its $37 million target.
Welltok operates in a particularly difficult digital health segment to monetize, patient engagement. The company launched in 2009, and has been marketing a software suite that lets patients and providers set health goals, and then tracks progress toward those goals through integration with fitness trackers, medical devices, and weight loss apps. Health systems and insurers can use the platform to incentivize healthy decision making by providing rewards when goals are met, and providers can use the platform .
In 2009, when the company launched, health systems had very little financial interest in providing these kinds of wellness solutions. As secondary care providers, hospitals were more focused on high bed utilization rates and maximizing billable services. Keeping patient's healthy when they were at home would have been counterproductive to their core business model. At the time, businesses like Welltok had to assume that health systems would not participate, and thus marketed to insurers and in some cases, directly to consumers. This resulted in patient engagement platforms that lacked an engaged physician community, and thus a sense of legitimacy. As a result, patient engagement platforms largely failed.
In 2010, the Affordable Care Act introduced hospital reimbursement programs that provided compelling financial incentives for keeping patients healthy and at home. The ACA also introduced financial penalties if patients were readmitted to the hospital with the same problem within 30 days. Fast forward four years, and these legislative changes seem to have been a catalyst that jumpstarted the now booming digital health industry, and patient engagement solutions are enjoying a second chance to prove themselves. This time, hospitals participating in accountable care reimbursement programs are taking the lead, with insurers and in some cases employers supporting the whole-team approach to engaging patients in their wellbeing, and keeping them healthy and at home.
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text:
I met Jun Yamadera at the SVForum Japan Pitch Night, March 10, 2016 in Menlo Park, CA. He reminded us about the 5 year anniversary of the earthquake and tsunami in the Tohoku region of Japan. His company is developing a cancer diagnostic system, and much of his work has been inspired by the strength and the fortitude of the people of Fukushima. http://www.nowhere.co.jp
His other company, Fukushima Wheel, http://fukushimawheel.org/
"A specially outfitted bicycle features environmental sensors to measure live city data such as radiation, temperature, humidity, NOX, and so on."
Both endeavors demonstrate the forward and innovative thinking from the new entrepreneurs in the Fukushima region.


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Michael Geist posted an assessment of the reports, drawing attention to the questionable methodology employed. The conclusions were drawn through a selective reading of data, with some data prepared by copyright industry associations. One of the reports, National Innovation Performance and Intellectual Property Rights, states that Canada ranks 19th worldwide. As Prof. Geist writes, "...the report fails to mention that Canada was actually tied with four other countries ranked 15th to 19th including the United States, which in the same paragraph is heralded as a leader in innovation whereas Canada is described a laggard."
Prof. Geist takes no prisoners and ably shows that the Digital Economy report borrowed heavily from the work of the International Intellectual Property Alliance without paying much attention to the courtesy of proper citation. In their rebuttal the Conference Board attempts to distance themselves from the charge of plagiarism. Moreover, they state "This report was produced as contract research. The Conference Board does not disclose the terms of its contracts without permission of the client." An ironic remark, given that Ontario taxpayers provided part of the funding for this venture.


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The way to defeat the First Amendment is not to cut it off at once, but to make it bleed to death from a thousand wounds. The government does this not by law, but by funding. It creates a military industrial complex that possesses a high demand for studies and plans and white papers and "research" (and I use quote marks because I am being sarcastic) about issues of importance to the state. Once you have this nexus of think tanks and government departments and NGOs, then all you need to do is create an environment of gossip.
Yes, all it takes is gossip. By pumping out a number of documents that redefine free speech as "low level terrorism" and redefine loyalty to the constitution as "violent extremism" the First Amendment can be neutralized in a word-driven military coup.
"A West Point think tank has issued a paper warning America about 'far right' groups such as the 'anti-federalist' movement, which supports 'civil activism, individual freedoms and self-government.' The report issued this week by the Combating Terrorism Center at the U.S. Military Academy at West Point, N.Y., is titled 'Challengers from the Sidelines: Understanding America's Violent Far-Right.'… It lumps limited government activists with three movements it identifies as 'a racist/white supremacy movement, an anti-federalist movement and a fundamentalist movement.'… The report also draws a link between the mainstream conservative movement and the violent 'far right,' and describes liberals as "future oriented" and conservatives as living in the past. 'While liberal worldviews are future- or progressive -oriented, conservative perspectives are more past-oriented, and in general, are interested in preserving the status quo." the report says. "The far right represents a more extreme version of conservatism, as its political vision is usually justified by the aspiration to restore or preserve values and practices that are part of the idealized historical heritage of the nation or ethnic community.' The report adds: 'While far-right groups' ideology is designed to exclude minorities and foreigners, the liberal-democratic system is designed to emphasize civil rights, minority rights and the balance of power.'"
I'm not going to respond to this transparent attempt to criminalize political opinions. It is one of several such reports that has come out and its objective is to create a monolithic bullying culture that can justify the use of force on people who do not submit to the liberal paradigm. It is a manifesto for those who, in the future, will kill Americans for being non-statist conservatives or libertarians or Christians.
But I notice that the perspective the Washington Time's article is completely naïve. It also says:
"The West Point center typically focuses reports on al Qaeda and other Islamic extremists attempting to gain power in Asia, the Middle East and Africa through violence… 'A Republican congressional staffer who served in the military told The Washington Times: 'If [the Defense Department] is looking for places to cut spending, this junk study is ground zero.' 'Shouldn't the Combating Terrorism Center be combating radical Islam around the globe instead of perpetuating the left's myth that right-wingers are terrorists?' the staffer said."
But anyone who reads in the newspaper about Libya or Syria knows that we actually use terrorists and fund them to overturn other nations. The point of the "war on terror" was never primarily about really defeating terrorism overseas. The point was to have a popular support for indefinite detention, Presidential kill lists of American citizens, drone attacks, warrantless wiretaps, and all the other tools of the totalitarian state to be used on American citizens. Now that it is all in place, it is time to redefine terrorism as loyalty to the Constitution and love for the American Republic.
We've known for at least three years that the Pentagon considers protesting to be "low level terrorism."
The noose is around our necks. Are we still going to pretend that it landed there by accident?


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Approximately 1,200 barrels of chemical weapons were dumped in various locations off Crimea's Black Sea coast by the Soviet Union as the invading Nazi army approached, according to an article published 09 February 2011 at VIKNO.EU. In a video-taped presentation, specialist Gennady Rubtsov estimated the metal barrels have an undersea life of 70 years. They were dumped in the sea in 1941. And so according to the math, time's up. One of the five chemical weapons listed, sarin, a nerve weapon, can kill a person in about two minutes. Regarding the radius of potential impact, Rubtsov estimates there's a 40 kilometer impact zone for one barrel.
The authorities in both Crimea and the nation's capital have downplayed any dangers on TV news, saying either they don't believe the scientific reports or there is no serious risk. However, according to tests at the Voenkonveer 43 laboratory in Kharkov, arsenic levels in water near the Swallows Nest tourist site are more than 100 times greater than normal. This is one of the 11 known locations where the chemicals were dumped, many near popular swimming beaches. Though the story has been featured early 2011 on a major news station, MTB News of Moscow, most people in Crimea have not heard of the situation. A member of the Ukraine Parliament noted during the MTB news interview that there is presently technology to seal the chemicals in barrels that will last up to 700 years, but no one seems to want to take responsibility for the reclamation process and for now the plan seems to keep the problem a secret so tourists aren't frightened away.
The following is a translation from Russian :
Simferopol, 08 February (New Region - Crimea, Anna Akhmetov) - Chemical weapons on the bottom Black Sea could completely disrupt the holiday season in Crimea . Chemicals dumped during the war in drums include lewisite, mustard gas, sarin and zaman and could leak at any moment.
News Source Novi Kanal (New Channel ) stated 1,200 metal barrels with chemical warfare agents lie along the entire coast of the Crimea. They were hastily scuttled in 1941 before the encroaching Nazi troops arrived. The contents of one container are enough to destroy all life within a radius of 40 kilometers.
Commissioned by the Ministry of Ecology of Ukraine, the environmental enterprise "Sitall" was hired to establish the whereabouts of 500 barrels and has identified 11 districts with the contaminated material. By 2010 the expected lifespan and integrity of the containers had expired.
"It is theoretically possible that in 2011 there will be breaches in these containers," stated the director of Sitall, Gennady Rubtsov.
The fact is, the barrels have already leaked, investigations indicated in the closed Kharkov Research Laboratory Voenkonveer 43 . Near the calling card of Crimea - the "Swallow's Nest " 24 barrels were dumped and the arsenic content in water is greater than the average rate by more than 100 times. This means that the mustard gas and lewisite, is likely to have leaked into the sea water.
"I do not see a big problem with that" said Sitall "I have no such information." - said the channel Deputy Prime Psarjov. – " I do not believe the data that you offer from the Kharkov Institute."
In the MOE (Ministry of Emergencies )report about the threat of chemicals, the director of the Department of Civil Defence Emergency Basil Kvashuk confirmed that the problem does exist.
"I'd rather not talk about it on television and brow-beat the inhabitants of the city of Sevastopol and the Autonomous Republic of Crimea. The problem really exists; we know where those tanks are. "- assured Kvashuk.
Apart from the fact that the whereabouts of 700 barrels at the bottom of the Black Sea have yet to established, the Azov Sea is known to have 360 containers of sarin and Zaman flooded by order of Khrushchev in 1956. According to Sitall, these tanks were already covered with a thick layer of silt. But because of the shallow Azov conditions their negative impact on the environment will be very large.
The recovery of these barrels of chemical weapons is not expected this year, since the budget for these purposes has not been provided.
Recall the situation, according to the Accounting Chamber of Ukraine, that for 10 years government programs related to ordnance explosives along the coast of Sevastopol and Kerch were organized with the MOE which received 55 million hryvnia from the state treasury. However, upcoming solutions are left with only one third of this, and the Crimean Black Sea coast is dotted with the remnants of munitions and chemical weapons flooded the Great Patriotic War. Containers, aerial bombs and artillery shells over time began to crumble, creating a potential threat to, and loss of, the recreational complex of the peninsula.
"For more than 10 years, the Ministry of Emergencies in fact demonstrated indifference to the problems of ecology and held a negligent attitude towards the people - those who live in Crimea, and those who come there to relax. A long time ago the millions of hryvnia, which had been dedicated from the budget, should have long since helped to clean the bottom of the Black Sea from the dangerous 'heritage' of the war!" - stated the head of the Accounting Chamber, Valentyn Symonenko. - But with this attitude to the ecology of our recreational pearl, the Black Sea, it is at risk of becoming a dead sea, if the MOE, together with the local authorities will not solve the problem responsibly."
With the existing methods of MOE, to neutralize military items to disarm one ship requires at least 25 years. Experts offer there's a need to expedite disposal either by moving munitions in modern light-weight containers with a guarantee of integrity for 700 years, or by using a special generator, through which at the molecular level can be neutralized to combat poisons. But the state has not allocated funds for this.
The following is a a more thorough videotaped interview of Gennady Rubtsov with fragments not included in this text outline by the news company "New Channel."
Thoughts on Crimea's Chemical Weapons
As was the case of Chernobyl and Fukushima, local Crimean citizens have been kept in the dark about the true health risks of the area. In keeping with human nature, there's a tendency for people in positions of authority to shirk their responsibilities regarding warning and protecting citizens, especially when they want to try and "save face," protect business interests, and avoid accountability. No matter how you slice it, allowing innocent people to suffer when suffering can prevented represents an inhumane and corrupt mindset.
The scriptures outline how the sin nature is like a poisonous serpent that brings forth death (Exodus 4:2-4
, John 3.14). In the book of Exodus, this metaphorical serpent was transformed into a staff of authority and raised up high by Moses. This symbolic staff is a picture of Jesus Christ, who was raised high on the cross and became sin for us that we may be completely cleansed of sin. Jesus Christ lived without sin and yet bore the responsibility and guilt of our sin, if we are simply willing to receive His gift of salvation and eternal life.
Though the poisonous barrels are out of sight at the bottom of the Black Sea, the poison is still there and will eventually bring death unless the poison is dealt with. Each one of us also has the poisonous and deadly sin nature within until it is truly dealt with by the spiritual power and authority of Jesus Christ. With all of the calamities taking place in the world, it seems as though we live in very uncertain times and it would be wise to repent and make peace with God if you have not already done so. This is true especially if you live in Crimea. Two minutes isn't very much time to say a final prayer of repentance.


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What Is The Liver Transplant Procedure And When Is It Done ?
Dr. Subhash Gupta
Liver transplantation has now become a well-accepted modality for the management of end stage liver disease. Liver transplantation involves removing the diseased liver from the patient and replacing it with healthy liver either from a brain dead person or more commonly with partial liver from a healthy donor. Retrieval of organs from brain dead people involves removal of organs from individuals whose brain has stopped functioning (typically resulting after head injuries and brain hemorrhage), but their heart and breathing functions are being supported with artificial support. These organs would be of great service to humanity, however owing to the social structure of our society these organ donations are far below what is needed. It is said that "Don't take your organs to heaven for only God knows that that there is a great need for them on earth". Owing to the scarcity of brain dead or "cadaveric" organs, the available resource is that for a healthy individual to donate a part of his liver for the patient. Owing to the huge functional reserve of a healthy that we initially talked about, the part of the liver remaining with the donor is sufficient to maintain normal functioning and the remaining liver grows back to it's normal size soon after donation.
When does one require a liver transplant?
Liver disease severe enough to require a liver transplant can come from many causes. In adults, the most common reason for liver transplantation is cirrhosis. Cirrhosis is a condition in which the liver slowly deteriorates and malfunctions due to chronic injury. Scar tissue replaces healthy liver tissue, partially blocking the flow of blood through the liver. Cirrhosis can be caused by viruses such as hepatitis B and C, alcohol, autoimmune liver diseases, buildup of fat in the liver, and hereditary liver diseases. Many people who develop cirrhosis of the liver due to excessive use of alcohol also need a liver transplant. Abstinence from alcohol and treatment of complications for 6 months will usually allow some of them to improve significantly and these patients may survive for prolonged periods without a transplant. For patients with advanced liver disease, where prolonged abstinence and medical treatment fails to restore health, liver transplantation is the treatment.
In children, the most common reason for liver transplantation is biliary atresia. Biliary atresia is a rare condition in newborn infants in which the common bile duct between the liver and the small intestine is blocked or absent. Bile ducts, which are tubes that carry bile out of the liver, are missing or damaged in this disease, and obstructed bile causes cirrhosis. Bile helps digest food. If unrecognised, the condition leads to liver failure. The cause of the condition is unknown. The only effective treatments are certain surgeries, or liver transplantation.
Other reasons for transplantation are liver cancer, benign liver tumors, and hereditary diseases. Primary liver cancers develop at a significantly higher rate in cirrhotic livers as compared to normal livers, particularly in patients having liver disease secondary to Hepatitis B. Liver Transplantation at an early stage of liver cancer may result in long-term survival for select patients. However, cancers of the liver that begin somewhere else in the body and spread to the liver are not curable with a liver transplant.
Is Chairman of Max Centre for Liver & Biliary Sciences, Max Super Speciality Hospital, Saket, New Delhi


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To SQL Server DBAs who are the shepherds of data in organizations, key GDPR questions, in general, center around whether data will need to be treated differently, safeguarded more etc. and specifically, as it relates to allowing production data to be used in testing.
That will be the focus of this article as we'll work our way through the details of this regulation as well as various authoritative articles on the subject, to address this key question. Then we'll look to ways and means to potentially ameliorate our findings to provide alternatives and workarounds if possible.Read more »


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Product parameters
Model No:JC-2B
Voltage:110V/ 220V 60Hz
Working size:15"*15" (38*38CM)
Temperature range:0-399℃
Time range:Adjustable
Packing size:74x49x48CM
Gross weight:46KG
15" x 15" heavy duty, even heating, swing away heat press platen
Full range pressure adjustment
Sturdy steel design
Suitable for material 1.5 "thick
Apply all types of transfer paper to 1.5 "thick
Separate digital timer included
Easy to use open and close handle with full range pressure adjustment
CE certifiication
How to print your digital photo onto T-shirt/Cloth/Garments
1. Obtain an image from the computer
2. Print the image with sublimation paper and ink by the printer
3. Put the paper on the t-shirt
4. Transfer the image to the t-shirt with swing away heat press machine
5. Remove the paper from t-shirt.
Machine Service
We have several ways of transporting the machine to our customers. Also they could choose their favorite way.
All swing away heat press machines will be packed with foam firstly, then they will be put in the strong carton case.
During our production of the machine, we will give you pictures, to ensure that the progress of production.
Life-long on-line technical support, Respond within 24 hours.


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Saturday, September 29, 2012
HolikaHolika HAUL~ (+ some stuff from Watson's)
14 comments:
Lovely haul! the blushes look like such cute colours =D plz do a look with them soon <3ReplyDelete
Cute pickups! I love korean makeup, it's so aesthetically pleasing. I can't wait to see how that lilac blush looks on you.ReplyDelete
Love the haul :] lashes, eyeliner, and blush<3 the blushes are such nice colors!ReplyDelete
really lovely haul *__*ReplyDelete
You got some nice stuff! Loveee the blushes, purple blushes are so cutee! Can't wait to see you use them :3ReplyDelete
- AnonymousOctober 16, 2012 at 5:19 AM
Nice haul Lina! I just discovered our KTown sell a lot of Korean cosmetics haha I was in awe... definitely go back to have a good look.. dont like talking to SA so Gmarket it is! Looking forward to seeing you sport your haul hahaReplyDelete
I love pen liners, so easy to draw a line. How did you find Clio's one? Have you ever try Tony Moly gel liners? They are famous.ReplyDeleteReplies
Nope, I actually saw them in store! I was VERY tempted to purchase one, but I went over my budget this month already and buying BLOCK.B's limited edition album on Friday will have me starving for the next two weeks! LOL. I got the Clio liner in store (Watson's) here in Korea! : DDelete
All ads and self-promotions WILL be deleted. Thank you for commenting! ^__^)/ 셀프프로모를하면안되세요. 댓글달으셔서고맙습니다


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