HEAT-SHRINKAGE LAYERED ADHESIVE TAPE Russian patent published in 2004 - IPC

FIELD: insulation materials. SUBSTANCE: invention provides two-layer material with polyethylene substrate and thermoplastic adhesive layer, which can be used for insulating underground pipelines. Object of invention is to widen reserve of heat- shrinkage layered adhesive tapes, to create the one based on cross-linked polyethylene and having adhesive layer based on ethylene copolymer, which would have high adhesiveness for metal. Tape according to invention comprises protective and adhesive layers, the former being polyethylene tape electronically and chemically modified to absorption of dose 25-50 MRad and oriented in lengthwise direction by 25-75% and the latter containing composition based on ethylene copolymer completed by polyisocyanate modifier and mineral filler. In particular, ethylene copolymer is composed of two ethylene/vinyl acetate copolymers differed by content of vinyl acetate groups by 5 to 20% and additionally contains third ethylene/vinyl acetate copolymer with 27-30% vinyl acetate groups and melt flowability index 15-30 g/10 min. All components are taken in specified proportions. EFFECT: widened reserve of anticorrosive tapes with elevated adhesive strength for metal. 2 tbl