Waterborne long alkyl chain branched copolymers used as release coatings synthesized by mini-emulsion polymerization

Abstract

Waterborne long alkyl chain branched copolymers with excellent release performance for pressure-sensitive adhesive were synthesized via mini-emulsion polymerization. Dynamic light scattering, video-based contact angle measurement and electronic stripping testing were employed to characterize and analyze the structure and release properties of the resultant copolymers. The results showed that ultrasonic amplitude of 50% and ultrasonic duration of 15min were the optimum conditions for the preparation of a mini-emulsion containing long alkyl chain monomer stearyl methacrylate (SMA). The ultimate conversion of monomers declined with increasing SMA, while the hydrophobicity of the copolymers increased. Release strength testing illustrated that the optimum amount of SMA for release coating was 60%, taking the cost factor into account, and better release performance could be obtained by increasing the coating thickness.