BITUMINOUS COMPOSITIONS CONTAINING COUPLED COPOLYMERS

摘要

The present invention relates to bituminous compositions used for roofing and waterproofing membranes or material comprising asymmetrical coupled polyvinyl aromatic-polydiene block copolymers having improved physical properties over broader ranges of service temperatures than those obtained from bituminous compositions prepared with symmetrical block copolymers of similar type. The asymmetry of the copolymer which is characterised by polyvinyl aromatic endblocks of at least two different molecular weights, one high and one low, ensures improved physical performance to roofing and waterproofing membranes made from such compositions.