Mussel-inspired polymer: A photocurable and degradable polymer network for adhesives

Abstract

Mussel-inspired polymer has long been desired for the next generation high adhesion strength bioadhesives. However, the currently synthetic method of mussel-inspired polymer was based on the conventional thermal polymerization. A large majority of thermal polymerizations need solvents, these solvents present risk of environment pollution. Different from the existing methods, here we introduce a facile route for the fabrication of mussel-inspired adhesives via UV polymerization. Meanwhile, polycaprolactone (PCL) was incorporated to enhance biocompatibility and biodegradability of adhesives. The investigated mussel-inspired adhesives (poly (L-DMA-GPCL-MA)) were synthesized with 3,4-dihydroxyphenyl-l-alanine acrylamide (L-DMA) and glycerol-polycaprolactone acrylate (GPCL-MA) under UV exposure. We systematically evaluated the effect of L-DMA and GPCL-MA on the UV polymerization kinetics, mechanical properties, thermal stability, adhesion and degradable properties of resulting adhesives. Our findings reveal that poly (L-DMA-GPCL-MA) shows excellent adhesive behaviors, the maximum adhesion of polymer on steel substrate was 3.2 ± 0.38 MPa, More importantly, it is able to stick to the low-energy surface substrates including Polypropylene (PP) and Polytetrafluoroethylene (PTFE). Furthermore, poly (L-DMA-GPCL-MA) shows faster degradation, the polymer lost around 40% of their initial weight after 48 day immersing into PBS (0.01 M, pH = 7.3). Based on these properties, poly (L-DMA-GPCL-MA) shows promise as a potential bio-inspired degradable adhesive.