Effect of rosin on the antibacterial activity against S.aureus and adhesion properties of UV-curable polyurethane/polysiloxane pressure-sensitive adhesive

Abstract Although polyurethane pressure-sensitive adhesives (PSAs) have been widely used, there are still some deficiencies in adhesion and heat resistance. To make up for these shortcomings, rosin is introduced into polyurethane/polysiloxane copolymer to improve its heat resistance and adhesion, while its hydrophobicity is also improved. The vinyl-terminated polyurethane/polysiloxane copolymer is synthesized by a one-pot polymerization method, and finally PSA with different content of rosin is obtained by UV radiation. The effects of rosin on heat resistance, hydrophobicity, viscoelasticity, adhesion and antibacterial of PSA have been studied. The results show that the heat resistance index, the contact angle and the peel strength of PSA are increased by 4%, 31 % and 88 % respectively when rosin content is 6 wt%. In addition, the storage modulus and loss modulus of PSAs enhance with the increase of frequency, and the storage modulus of PSAs is always higher than the loss modulus. All PSAs have good antibacterial properties, with an antibacterial rate above 99.2 %. This will help expand the application of polyurethane/polysiloxane PSA such as food packaging materials.