SYNTHESIS OF POLYMERS WITH CARBOXY END GROUPS BY REACTION OF POLYSTYRYL ANIONS WITH 4-BROMO-1,1,1-TRIMETHOXYBUTANE

Well-defined polystyrenes with terminal carboxy groups were synthesized by the reaction of living polystyryl anions with 4-bromo-1,1,1-trimethoxybutane, followed by treatment with 0.1 N HCl at first and then with 0.2 N LiOH. The polymers thus obtained were carefully analyzed by size-exclusion chromatography (SEC), acid-base titration using potassium methoxide, H-1 and C-13 NMR, IR, and thin-layer chromatography (TLC)-flame ionization detection (FID). The analytical results indicated that the polymers had terminal carboxy groups with high degrees (> 95%) as well as predictable molecular weights and narrow molecular weight distributions (M(w)BAR/M(n)BAR < 1.1). Chromatographic separation by TLC based on SiO2 and quantitative analysis by FID for polymers with terminal carboxy groups were discussed.