Chemical inhomogeneity of terpolymers of styrene with acrylonitrile and methyl methacrylate

• Published in: Polymer science USSR 1983, Vol.25 (6), p.1337-1345
• Main Authors: Vasilova, O.I, Kucher, R.V
• Format: Article
• Language: English
• ISSN: 0032-3950; 1878-268X
• DOI: 10.1016/0032-3950(83)90067-9

The method of light scatter has been used to study terpolymers of styrene with acrylonitrile and methyl methacrylate of the following composition (in parts by weight) 0·65 : 0·13 : 0·22 (copolymer 1), 0·60 : 0·14 : 0·26 (copolymer 2), 0·52: 0·15 : 0·33 (copolymer 3) and 0·30 : 0·07 : 0·63 (copolymer 4), and the fractions of copolymer 4 obtained from the solvent-precipitant system methylethylketonemethanol to make a quantitative evaluation of the general parameters of chemical inhomogeneity P A, P B, Q A, Q B and R. The measurements were made in methylethylketone, THF, 1,4-dioxane, toluene, chlorobenzene, bromoform, bromobenzene and aniline. It was found that the overall chemical inhomogeneity Q/ Q max of the samples studied even for low (≈10%) depths of conversion is high for compositions near to (copolymers 1 and 2) and distant from (copolymers 3 and 4) the azeotropic region, being 28 and 59–62% respectively. The chemical inhomogeneity of the fractions is close to that for the initial sample, which indicates the suitability of the system methylethylketone-methanol for separating copolymer 4 by molecular weight.