Synthesis of Dilithium α,ω-Disulfonated Polystyrene by Anionic Polymerization

Abstract

The chain-end sulfonation of α,ω-dilithiopolystyrene prepared by lithium naphthalenide as a difunctional initiator using 1,3-propanesultone was studied by the characterization methodologies such as acid/base titration, colorimetric method using methylene blue, two-phase titration with Hyamine 1622, size exclusion chromatographic analysis infrared, and 1H NMR spectroscopic analysis. The reactivity modification of α,ω-dilithiopolystyrene through the end-capping with 1,1-diphenylethylene prior to the sulfoalkylation in benzene-tetrahydrofuran (THF) (10 : 1, v/v) at 25°C with excess 1,3-propanesultone is suggested as a useful method for the preparation of the corresponding dilithium α,ω-disulfonated polystyrene in relatively high yield based on the results from the acid/base titration (>85%).