DIBLOCK COPOLYMER AND PRESSURE-SENSITIVE ADHESIVE COMPOSITIONS CONTAINING THE SAME

摘要

An acrylic diblock copolymer of the general formula (I) useful in producing pressure-sensitive adhesives which are improved in cohesive force, tack and hot-melt applicability without impairing the heat resistance and weather resistance; and pressure-sensitive adhesive compositions containing the copolymer: X .cndot. Y (I) in which X is a polymer block composed of alkyl methacrylate units wherein the alkyl is one having 1 to 4 carbon atoms or on e having a cyclic structure; Y is a polymer block composed of alkyl acrylate units wherein the alkyl has 1 to 20 carbon atoms and/or alkyl methacrylate units wherein the alkyl has 5 to 20 carbon atoms; the weight-average molecul ar weight (Mw) of X is 1,000 to 8,000; and the X/Y mass ratio ranges from 1/99 to 10/90.