G&E Blended HIIR Mixture of halogenated isoprene/isobutylene polymers Goldsmith & Eggleton Rubber - Elastomer >> Polyisobutylene, PIB Rubber - Elastomer >> Polyisoprene rubber, IR SEALANT ADHESIVE Halogenated isoprene/isobutylene copolymer. Used in adhesives and sealants and also for preformed tapes. G&E Blended Halogenated Butyl is excellent for cost reductions in applications such as non-cured tapes, construction adhesives and caulks. Halogenated isoprene/isobutylene copolymer. Used in adhesives, sealants and caulks.