Abstract: Transparent receptor substrates, well suited for electrostatic reprography, e.g., for the production of overhead transparencies, exhibit excellent transparency, good slip, good adhesion of toner thereto and good electrical conductivity, comprise (i) a transparent composite polyester base(s) having (ii) a toner-receptive primer coating (P) on at least one of the face surfaces thereof, such composite polyester base comprising (a) a thick layer (A) of semicrystalline polyester and (b) a thin layer (B) of an identical or different polyester adhered to at least one of the face surfaces of said thick layer (A), and the at least one primer coating (P) comprising an acrylic polymer having a glass transition temperature ranging from 10.degree. C. to 50.degree. C., a free --COOH carboxylic functional group content less than 50 millimoles per 100 grams of said acrylic polymer and a thickness no greater than 0.3 .mu.m.

Abstract: Polymer compositions, typically thermoplastic polymer compositions, readily converted into electroconductive polymers and articles shaped therefrom, e.g., films, comprise at least one convertible polymer support substrate (A) and at least one amphiphilic heterocyclic monomer (B) having the formula (I): ##STR1## in which R.sub.1 and R.sub.2, which may be identical or different, are each a linear or branched alkyl, aryl, alkylaryl, arylalkyl, hydroxycarbonyl, alkoxycarbonyl or amide radical; X is an oxygen or sulfur atom or the divalent radical ##STR2## wherein R.sub.3 is a hydrogen atom or an alkyl, aryl, alkylaryl or arylalkyl radical; at least one of the substituents R.sub.1, R.sub.2 and R.sub.3 having an amphiphilicity-imparting number of carbon atoms.