Block Copolymer-Based Hot-Melt Pressure-Sensitive Adhesives

Abstract

Pressure-sensitive adhesives (PSAs) based on block copolymers have comprised an area of fast growth. Acrylic block copolymers expand the block copolymer technology to a wide range of PSA applications. The emergence of block copolymers greatly stimulated the growth of the hot-melt PSAs (HMPSAs) business. The styrenic block copolymers-based HMPSAs are covered next, with detailed discussion on formulation principles, rheological and tensile properties, and the functions of the major ingredients. The broad range of polymer grades provides versatility for the formulators to design HMPSAs for very diverse performance requirements. The architecture of the polymer chains, whether they have a linear, radial, or tapered structure, also impacts the physical properties and performance of the formulated Styrenic Hot-Melt. A simple way to test compatibility is to dissolve an equal amount of tackifier and polymer in a solvent such as toluene and then cast a film to check the clarity of the blend.