G&E Blended Polyisobutylene HMW Polyisobutylene Goldsmith & Eggleton Rubber - Elastomer >> Polyisobutylene, PIB SEALANT ADHESIVE Polyisobutylene. Used in adhesives and sealants and also for preformed tapes. G&E Blended Polyisobutyl is excellent for cost reductions in applications such as sealants and adhesives, polymer modification and membranes when used as a partial replacement for prime Polyisobutyl. Polyisobutylene polymer. Used in adhesives and sealants.