UNCROSSLINKABLE ADHESIVE COMPOSITION AND METHOD OF PRODUCING THE SAME, AND ADHESIVE SHEET

摘要

PROBLEM TO BE SOLVED: To provide an uncrosslinkable adhesive composition that mainly comprises a block copolymer of the polystyrene components and the polyacrylic components, shows good adhesive properties at room temperature and can easily variate the adhesive composition. SOLUTION: Styrene monomers and acrylic monomers are subjected to the living radical polymerization in a proper sequential monomer order by using a polymerization initiator in the presence of a transition metal and its ligand to produce the block copolymers of the A-B type or A-B-A type where A is the styrene polymer block and B is the acrylic polymer block. The number- average molecular weight of the total polymer is >=70,000, the styrene polymer block A amounts to 5-45 wt.% based on the total polymer and the glass transition point of the single block polymer of the acrylic monomer is <=-20 deg.C. The block copolymer is directly used as a main component for the adhesive without crosslinking.