Pressure-Sensitive Adhesives Based on CO₂-Βased Polymer: Structure-Regulated Viscoelasticity

Pressure-sensitive adhesives (PSAs) are polymers with tunable viscoelastic properties, primarily determined by the structural configuration of their polymer chains. In this study, we report the development of a CO₂-based poly(carbonate-ether) for use in PSAs applications, synthesized via the copolymerization of CO₂ and propylene oxide. The viscoelastic properties of the resulting polymer can be precisely modulated by varying its molecular weight (M_n) and carbonate unit (CU) content, yielding excellent comprehensive performance without the need for additional tackifiers or additives. Notably, PCE9, with a M_n of 90 kg/mol and a CU content of 50 %, exhibited optimal performance, achieving a 180° peel strength of 5.70 N/cm with adhesive failure upon peel-off, and maintaining static shear adhesion for up to 2760 minutes. This development of CO₂-based copolymers for PSAs applications not only represents a novel approach to the utilization of CO₂-derived materials but also provides an innovative pathway for the sustainable advancement of the PSAs industry.