CO_(2)-based Biodegradable Supramolecular Polymers with Well-tunable Adhesive Properties

Supramolecular adhesives that enable debonding on-demand are of significant research interest for the development of adaptive and smart materials,yet,biodegrable supramolecular adhesives have been rarely exploited.Herein,telechelic,three-armed and four-armed CO_(2)-based polyols with close molecular weights and various content(or carbonate unite content)have been synthesized via a zinc-cobalt double metal cyanide complex catalyzed ring-opening copolymerization of CO_(2) and propylene oxide,and further exploited as sustainable and biodegradable building blocks for supramolecular polymers(SMPs)with 2-ureido-4[1H]-pyrimidinone(UPy)motifs.Notably,the orthogonal modulation of the CO_(2) content and the topology of CO_(2)-based polyols provide a unique opportunity to fine-tune the surface energy as well as the cohesive strength of the resulting CO_(2)-based SMPs.Notably,a three-armed SMP with 44%CO_(2)(3UPy-CO_(2)-44%)can well balance the trade-off between surface energy and cohesive strength,therefore bestowing a high adhesive strength of 7.5 and 9.7 MPa towards stainless steel and wood substrates respectively by testing the corresponding single lap joints.Moreover,the light-responsive adhesion property of 3UPy-CO_(2)-44%has been demonstrated exemplarily by blending with a UV sensitizer.