1  5,854,314  2  CROSSLINKABLE WATERBORNE  DISPERSIONS OF HYDROXY FUNCTIONAL  POLYDIENE POLYMERS AND AMINO  RESINS  DETAILED DESCRIPTION OF THE  INVENTION  BACKGROUND OF THE INVENTION  SUMMARY OF THE INVENTION  The hydroxy functional polydiene polymers may have  molecular weights of from about 1,000 to about 3,000,000.  The present invention also contemplates linear unsatur› ated or hydrogenated isoprene polymers having one to two  terminal hydroxy groups per molecule and also such poly› mers having additional hydroxy groups. Preferably, the  isoprene polymers have greater than 80% 1,4-addition of the  isoprene and hydrogenation of at least 90% of the polymer› ized isoprene. The polymers are preferably prepared by  anionic polymerization in the absence of microstructure  modifiers that increase 3,4-addition of the isoprene.  In a preferred embodiment of the present invention, the  compatible amino resin is a butylated amino resin and the  surfactant is an anionic surfactant composed of an amine salt  of an acid which can be used to catalyze the crosslinking of  the polymer and the amino resin such as paratoluene sul› fonic acid or dodecylbenzene sulfonic acid.  The anionic polymerization of the conjugated diene  hydrocarbons is typically carried out in a hydrocarbon  solvent containing a structure modifier such as diethylether  or glyme (1,2-diethoxyethane) to obtain the desired amount  of 1,4-addition.  As  described in Re. 27,145 which is incor› porated by reference herein, the level of 1,2-addition of a  butadiene polymer or copolymer can greatly affect elasto- meric properties after hydrogenation. The 1,2-addition of  1,3-butadiene polymers having terminal functional groups  significantly and surprisingly influences the viscosity of the  polymers. A 1,2-addition of about 40% is achieved during  polymerization at 50° C. with about 6% by volume of  diethylether or about 1000 ppm of glyme in the polymer› ization solvent.  wherein  B  represents polymerized units of one or more  conjugated diene hydrocarbons such as butadiene or  isoprene,  A  represents polymerized units of one or more  vinyl aromatic compounds such as styrene, and  X is  the  residue of a monolithium initiator such as sec-butyllithium.  B  can also be a copolymer of a conjugated diene and a vinyl  aromatic compound.  B$_{1 }$ and  B$_{2 }$ are formed of different  dienes.  It  is one object of the present invention to provide a  crosslinkable waterborne dispersion of hydroxy functional  polydiene polymers and amino resins. Another object of this  invention is to provide a method for making such crosslink› able waterborne dispersions.  Hydroxy functional polydiene polymers are well known.  It  has been shown that formulations containing these  polymers, a melamine resin, and an acid catalyst can be  cured by baking under normal bake conditions.  If such  formulations could be dispersed in water, the utility of these  polymers would be greatly broadened. This would allow  preparation of low viscosity, waterborne formulations hav› ing very low volatile organic compound (VOC) contents. By  adding waterborne hydroxy functional polydiene polymer  dispersions to other water-based products having compatible  surfactant systems, these polymers could be used to modify  other types of resins and this could be done without concern  about phase separation due to incompatibility of the hydroxy  functional polydiene polymers and solvent-based resins.  Hydrogenated polybutadiene dials are preferred for use  herein because they are easily prepared, they have low glass  transition temperature, and they have excellent weatherabil› ity. The dials, dihydroxylated polybutadienes, are synthe› sized by anionic polymerization of conjugated diene hydro- carbons with lithium initiators. Monools and polyols can  also be synthesized in the same manner. This process is well  known as described in U.S. Pat. Nos. 4,039,593 and Re.  27,145 which descriptions are incorporated herein by refer› ence. Polymerization commences with a monolithium,  dilithium, or polylithium initiator which builds a living  polymer backbone at each lithium site. Typical monolithium  living polymer structures containing conjugated diene  hydrocarbons are:  This invention relates to waterborne dispersions of  hydroxy functional polydiene polymers. More specifically,  the invention relates to waterborne dispersions of such  polymers and amino resins which can be crosslinked to  make cured films, coatings, adhesives, sealants, caulks,  binders and modifiers for asphalt.  The hydroxy functional polydiene polymers of the present  invention are monools, dials, and polyols of hydrogenated  and unhydrogenated low molecular weight diene homopoly› mers and copolymers with more than one diene and/or a  vinyl aromatic hydrocarbon. Such copolymers will usually  be random copolymers or tapered block copolymers since it  is difficult to make low molecular weight copolymers with  a sharp division between blocks because the crossover  reaction from one monomer to the other is usually slow  compared to the progagation reaction. Suitable polymers  include monools, dials, and pol yo ls of low molecular weight  polybutadiene and polyisoprene and their copolymers with  styrene, either hydrogenated or unhydrogenated.  This is a division of application Ser. No. 08/679,164,  filed Jul. 12, 1996, now U.S. Pat. No. 5,721,317 which is a  continuation of Ser. No. 08/479,583 filed Jun. 7, 1995,  abandoned, which is a continuation of Ser. No. 08/277,375,  filed Jul. 18, 1994 abandoned.  The present invention provides a water dispersion of a  crosslinkable hydroxy functional polydiene polymer com› position which comprises:  (a) 10 to 65% by weight(% w) of a hydroxy functional  polydiene polymer,  (b) 0.2 to 25% w of a compatible amino resin,  (c) 0.1 to 10% w of a nonionic surfactant or an anionic  surfactant having a volatile cation, and  ( d) the balance water.  X-B-Li  X-A-B-Li  X-A-B-A-Li  X-B$_{1}$-B$_{2}$-Li  X-A-B$_{1}$-B$_{2}$-Li  This invention also describes processes for making such  crosslinkable waterborne dispersions. One method involves  making a hot aqueous solution of the surfactant, adding a  mixture of a hydroxy functional polydiene polymer and a 60  compatible amino resin to the hot aqueous solution, and then  mixing the components under high shear conditions. The  preferred method involves mixing together at a temperature  of 25°  to 90°  C. with vigorous agitation a hydroxy functional  polydiene polymer, an amino resin, and the desired 65  surfactant, and then adding water to the mixture slowly over  a period of at least 15 minutes. 