Grafted polypropylene containing chlorohydrin groups—II: Analysis of polymer and its reactivity

Abstract

I.R. analysis of isotactic powdered polypropylene containing acrylic acid grafts, with acidic groups esterified with epichlorohydrin, has revealed that the carbonyl contents gradually increase when the esterification is carried out at 90 to 120° while the concentration of hydroxyl groups changes proportionally to the content of chlorohydrin groups in the polymer. At esterification temperatures exceeding 90°, the product loses chlorine by hydrogen chloride elimination. The observed data are in accordance with the mechanism of dehydrochlorination of chlorohydrin groups without intermediate formation of the epoxide ring. From the polymer containing chlorohydrin groups, no chlorine is evolved even at temperatures as high as 120°. During thermal treatment with a basic reagent, the generated epoxy-ring remains only partially. When there are also primary or secondary amines in the system, the transformation to the epoxide is enhanced, the amine being eventually bonded to polymer.