ACRYLATE COPOLYMER PRESSURE SENSITIVE ADHESIVE

摘要

The invention provides normally tacky and pressure-sensitive adhesive compositions comprising a polymer having an inherent viscosity greater than 0.2 and having in its backbone at least a major portion by weight of polymerized monomeric acrylic or methacrylic acid ester of a non-tertiary alcohol and, having attached to the backbone, polymeric moieties having a weight average molecular weight of above about 2,000 and a Tg of above about 20 DEG C. The number and composition of the attached moieties in the polymer is such as to provide the adhesive composition with a shear holding value of at least 50 minutes. Sheet materials coated with the adhesive composition are also provided. Preferred adhesive composition comprises a copolymer monomeric acrylic or methacrylic acid ester of non-tertiary alcohol and macromolecular monomer. The copolymer may also include up to 12% by weight of a copolymerizable polar monomer such as acrylic acid.