POLYURETHANE ZWITTERIONOMERS USING 2,3-DIHYDROXYPYRIDINE

A polyurethane-containing pyridinium moiety was prepared by chain exte nsion of the isocyanate terminated prepolymer based on poly(tetramethy lene oxide) glycol and tolylene diisocyanate with 2,3-dihydroxypyridin e. This was converted into zwitterionomer by the reaction with 1,3-pro pane sultone. The polyurethane and zwitterionomers were characterized using FTNMR and FTIR. The thermal stability of the polymers was determ ined using a thermogravimetric analyser. Studies by dfferential scanni ng calorimetry (DSC) showed that as the ionic content in the polymer c hain increases phase separation takes place and the glass transition t emperature (T-g) shifts towards lower values. The mechanical propertie s of the polymers revealed that tensile strength increases and elongat ion decreases as the ionic content in the polymer increases. Copyright (C) 1996 Published by Elsevier Science Ltd.