Study of UV-initiated polymerization and UV crosslinking of acrylic monomers mixture for the production of solvent-free pressure-sensitive adhesive films

UV-polymerizable and UV-crosslinkable pressure-sensitive adhesive acrylic compositions are widely applied for high-quality carrier-free films, one-sided or double-sided self-adhesive tapes. Comprehensive studies of the properties of novel acrylic PSAs for carrier-free films or adhesive tapes were carried out. Solvent-free acrylic pressure-sensitive adhesive layers were UV-crosslinked using various photoreactive crosslinking agents. Polymer content during UV-polymerization, prepolymers viscosity, temperature changes of prepolymer during UV-initiated polymerization process were investigated. The chemical structure of prepolymer and polymerized acrylic film were examined using FTIR spectroscopy. Prepolymer mixtures were transferred on the transparent carriers to form 1 mm thick polymer films, and then UV-crosslinked after the addition of the selected acrylic crosslinker. Final adhesive films were then tested to evaluate their functional properties as the tack, peel adhesion, and shear strength at 20 °C and 70 °C. From the results reveal that both concentrations of acrylic acid in the prepolymer, and cross-linking agent in the final polymer layer, have a significant influence on the functional properties of the produced PSA films.