Compositions Including Copolymers of Isobutylene and Paramethylstyrene Substantially Free of Paramethylstyrene Monomers and Methods of Making the Same

Abstract

A process for preparing a cement composition comprising an isoolefin-alkylstyrene copolymer and substantially free of an alkylstyrene monomer is described herein. The process comprises reacting the isoolefin monomer with at least a portion of the alkylstyrene monomer in a diluent to form an isoolefin-alkylstyrene copolymer, replacing the diluent with a solvent, reacting a halogenic scavenger with the unreacted alkylstyrene monomer in an absence of a free radical initiator in order to form a halogenic alkylstyrene compound without altering the isoolefin-alkylstyrene copolymer, and removing the halogenic alkylstyrene compound from the slurry to form the cement composition substantially free of the alkylstyrene monomer. Also disclosed herein is a composition comprising an isoolefin-alkylstyrene copolymer and an alkylstyrene monomer comprising a concentration less than about 20 ppm.

Dependencies are inferred from the claim text.