DILUTE SOLUTION PROPERTIES OF STYRENE-ACRYLONITRILE AND STYRENE-METHYL METHACRYLATE COPOLYMERS - 1. INTRINSIC VISCOSITY-MOLECULAR WEIGHT RELATIONS.

In the reported experiments, Styrene-acrylonitrile (St-AN) copolymers of three compositions were prepared by bulk polymerization at 60 degree C with benzoyl peroxide as the initiator, and were then fractionated. The mol. wt of unfractionated and fractionated samples were determined by light scattering in a number of solvents. The left bracket n right bracket versus M//w relations at 30 degree C were established. It is demonstrated that the solvent power decreases with an increase in AN content. The solvent power of the three solvents used for SM copolymer sample is practically the same within experimental errors. From the a values it is concluded that in a given solvent the copolymer chains are more extended than the corresponding homopolymers.