Properties of UV-curable solvent-free pressure sensitive adhesive

Abstract

In this study, the effects of methyl methacrylate (MMA), trimethylolpropane triacrylate (TMPTA), difunctional silicone urethane acrylate oligomer, and UV-dose on the adhesive properties of UV-curable pressure-sensitive adhesives (PSAs) were investigated, for further optimizing the adhesive properties to meet the requirements on high holding power and low peel strength. The results illustrated that increasing the MMA content decreased the peel strength and improved the holding power. The variation of TMPTA content from 1 to 10 wt% significantly enhanced the holding power from 1 h to above 120 h. The gel fraction increased with increasing TMPTA content. This increment was caused by the cross-linking of TMPTA after UV exposure. The peel strength of UV-curable PSAs was reduced to zero when oligomer content was more than 40 wt%, whereas the holding power was significantly enhanced from 5 h to above 120 h as the oligomer content increased up to 70 wt%. When the UV-dose increased, the peel strength decreased and the holding power increased. Therefore, UV-curable PSAs with very low peel strength and high holding power above 120 h were successfully synthesized and they possessed desirable features which could be fabricated to meet the specific requirements for industrial applications.