7  5.783,111  8  The second important role of the substituted aromatic  compounds of the present invention is that of a "compati› bilizer" in blends of the conductive polyaniline complexes  and insulating or semiconductive polymers or pre-polymers.  The designation "compatibilizer" hereinafter refers to a  species that improves the interaction between two immis- cible liquid phases through close matching of the physio› chemical nature of the species and the two liquids. Thus, for  example. common surfactants reduce the interfacial tension  of water and oil. and. therewith "compatibilize" these two  liquids. as it is understood in this invention. This compati- bilizing is achieved in this simple example by providing a  species (the surfactant) that has two covalently bonded  moieties: one of which that strongly interacts with water;  and the other moiety that has a favorable interaction with oil.  The compatibilizing role of the substituted aromatic com- pounds according to the present invention in blends of the  conducting polyaniline complexes and insulating or semi› conductive polymers is similarly understood. For example.  Particularly preferred for the use in the practice of this  invention. is the electrically conducting polyaniline that is  derived from the non-conducting unsubstituted polyaniline  and protonated to its electrically conducting form by the use  In general. the non-conducting forms of polyanilines  useful for the preparation of the electrically conductive  polyaniline salt complexes used in practice of this invention  are those which are of sufficiently high molecular weight to  exhibit high electrical conductivity; i.e .•  those polyanilines  having a weight average molecular weight of more than  5.000 daltons. In general substituted and unsubstituted  polyanilines and polyaniline copolymers will be of at least  20 repeat units. In the preferred embodiments of the  invention. the number of repeat units is at least about 25. and  in the most preferred embodiments. the number of repeat  units is at least about 50.  The non-conducting polyaniline used for the preparation  of the electrically conductive polyaniline salt complexes  according to practice of this invention can be in any of its  physical forms. lliustrative of useful forms are those  described in U.S. Pat. Nos. 5.232.631 and 4.983.322. incor› porated by reference herein. For unsubstituted polyaniline.  useful forms include leucoemeraldine, protoemeraldine,  emeraldine. nigraniline and pernigraniline forms. Useful  polyanilines can be prepared by any chemical and electro› chemical synthetic procedures referred to, for example. in  the above references incorporated herein.  Unlike commonly used plasticizers. which in the art of  conductive polymer processing often are added to improve  dispersion of solid conductive particles in molten polymers,  the substituted aromatic compounds used according to the  present invention. during processing dissolve the electrically  conductive polyaniline salt complexes. and form strong  molecular associations with them. Due to this unique  feature. the conductive polyaniline salt complexes during  processing are in their fluid form. which has the above  described major advantages with regard to product  homogeneity. properties, and shaping options. And. unlike  commonly used solvents. the substituted aromatic com› pounds according  to the present invention form a permanent  and integral part of the compositions. Interestingly, and  Slllprisingly. the molecular interactions between the substi› tuted aromatic compounds and the electrically conductive  polyaniline salt complexes may be so strong •.  that their  mixtures can form the extraordinary class of materials  known as crystalline solvates. These materials exhibit novel  crystalline structures that are different from each of their  constituent. and have many useful properties, such as con- trollable melting temperatures. In addition. depending on the  specific properties of the substituted aromatic compounds.  such solvates may exhibit unusual electrical, optical mag› netic and mechanical characteristics.  One ingredient in the present compositions is electrically  conducting unsubstituted or substituted polyaniline salt  complexes or an electrically conducting polyaniline copoly› mer salt complex, or mixtures thereof, as described in U.S.  Pat. Nos. 5.069.820 and 5.160.457 and U.S. Pat. No. 5.232.  631. When the term "electrically conducting polyaniline salt  complex" is used in this application. it is used generically to  include electrically conducting unsubstituted and substituted  polyanilines and electrically conducting polyaniline  copolymers. and mixtures thereof. that have been rendered  electrically conducting by protonation of the corresponding  non-conducting forms of polyanilines by the use of one or  more strong protonic acids with a pKa value of less than  about 3.0; unless the context is clear that only the specific  nonsubstituted form is intended.  Furthermore. the inventors have discovered extremely  unusual crystalline solvates of electrically conductive polya› niline salt complexes and substituted aromatic compounds.  The latter compositions are remarkable in that they exhibit  novel crystal structures that are different from either of their  constituents; and have controllable melting temperatures.  The Electrically Conducting Polyaniline  A second. critical ingredient of the compositions of the  present invention is one or more particular substituted  aromatic compounds. The unique roles of this substance are  that of a "solvent-plasticizer" of conductive polyaniline  complexes; and. additionally. of "compatibilizer" in blends  of the conductive polymer with insulating or semiconductive  polymers or prepolymers.  The Substituted Aromatic Compound  Protonic acids are well known as dopants in the conduc› tive polymer art as shown by the reference to  J. C. Chiang  and A. G. MacDiarmid; the reference to W. R. Salaneck et  al and to U.S. Pat. Nos. 5.069.820 and 5.232.631.  of one or more protonic acids that have a pKa value of less  than about 3.0. Preferred protonic acids are those that  protonate the polyaniline to form a salt complex. having an  electrical conductivity of greater than about 10-6  Siem.  Among the preferred protonic acids. particularly preferred  are those that belong  to the class of acids that impart a  conductivity of greater than about 10- 3  Siem to the salt  complex with polyaniline. Amongst these particularly pre› ferred embodiments. most preferred are those embodiments  in which said polyaniline salt complex has a conductivity  greater than about 1  Siem.  mixtures thereof. which is fluid during compounding or  mixing with (i) and  (ii) and/or during shaping into the  conductive article.  SU1prisingly. the inventors have discovered that. unlike  the electrically conductive compositions described in the  prior art. the materials according to the present invention,  which do not contain an excess protonic acid,  v. a remarkably low percolation threshold for the onset of  conductivity.  iv. exhibit improved compatibility between the conduct› ing polyaniline salt complex and the matrix material;  which results in  iii.  are less hygroscopic; and. in addition, in blends with  insulating or semiconducting matrix polymers:  ii.  are substantially less acidic; and  i. display outstanding processability in the fluid form. i.e.  solution or melt; 