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Relative reactivities and graft distributions of polystyrene Macromers® in vinyl chloride copolymerization
Author(s) -
Schulz Gerald O.,
Milkovich Ralph
Publication year - 1994
Publication title -
polymer international
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.592
H-Index - 105
eISSN - 1097-0126
pISSN - 0959-8103
DOI - 10.1002/pi.1994.210330204
Subject(s) - macromonomer , copolymer , polymer chemistry , vinyl chloride , vinyl ether , reactivity (psychology) , polystyrene , materials science , methacrylate , vinyl polymer , maleic anhydride , polymer , chemistry , organic chemistry , medicine , alternative medicine , pathology
Polystyrene macromonomers terminated with methacrylate, vinyl ether, or maleic half ester functionalities were evaluated in free radical initiated copolymerizations with vinyl chloride in aqueous suspension polymerization. Macromers® (M 1 ) terminated with methacrylate disappeared very rapidly in copolymerization with vinyl chloride (M 2 ). The relative reactivity ratio, r 2 , was determined to be 0.05 in good agreement with literature values of about 0.04. Vinyl ether‐terminated Macromers® had unexpectedly uniform reactivity with vinyl chloride in early conversion samples, but macromonomer conversion was incomplete. Macromers® having maleic half ester functionality were incorporated rapidly in vinyl chloride copolymerization at pH 2.5 ( r 2 = 0.13). However, at pH 10 these Macromers® had reduced reactivity ( r 2 = 0.34), which improved graft polymer uniformity. These Macromer® copolymerization relative reactivities are shown to be useful in predicting and controlling graft densities and graft polymer heterogeneity which influence morphology, processing, and mechanical properties.