High performing biocompatible solvent-free pressure-sensitive adhesives derived from acrylated epoxidized linseed oil

A solvent-free method for developing green pressure-sensitive adhesives offers biocompatibility, non-toxicity, cost reduction, and sustainability, positioning it as a superior alternative to conventional PSAs. Herein, epoxy groups were introduced into the linseed oil backbone by epoxidation and further functionalized by acrylic acid mediated ring opening to form acrylated epoxidized linseed oil (AELO) with ∼62.3 % biomass and ∼84 % renewable content. Thereafter, synthesized low T_g monomer was copolymerized with methyl methacrylate (MMA) in different molar ratio via solvent-free approach to obtain bio-based PSAs. The chemical analysis confirms the successful polymerization of PSAs, which are thermally stable and exhibit single glass transition temperatures ranging from – 44 to – 23 °C, desired for a commercially performing PSA. The storage modulus values met the Dahlquist criterion and viscoelastic window lies in removable PSAs category. The maximum peel strength of 3.58 N/in. and tackiness of 5.05 N were obtained by PSA 1/1 (AELO: MMA = 1:1 M ratio), whereas static shear strength of 711 min by PSA 1/3, which were found superior to commercially available medical tapes and food labels. The developed PSA 1/1 exhibits 58.1 % biomass content, >90 % HaCaT cell viability at 100 mg/ml, superior biodegradability (41 % weight loss in 15 days), and enhanced antimicrobial activity with a 7 mm inhibition zone against E. coli ATCC 25922. The reported synthesis strategy and developed AELO-based PSAs pave the way for sustainable framework and motivating a paradigm shift towards green PSAs in multiple industry sectors spanning food packaging and pharmaceuticals.