Effect of cyclohexyl methacrylate (CHMA) on the comprehensive properties of acrylate emulsion pressure sensitive adhesives

Abstract

Cyclic methacrylate monomer cyclohexyl methacrylate (CHMA) was evaluated as an alternative to traditional methyl methacrylate (MMA) as hard monomer in the application of acrylate latex pressure sensitive adhesive (PSA). The influences of CHMA on the resultant latex and PSA properties were comprehensively investigated. Both FTIR and 1H NMR analysis indicated that CHMA could be successfully introduced into the latex PSA copolymer through emulsion polymerization. TEM images illustrated that the synthesized latex particles are spherical and uniform. DSC and TGA results showed that Tg of the copolymer was elevated, while thermal stability was decreased with introduction of CHMA. Besides, it was also found that water resistance of the latex PSA was improved by the presence of CHMA, confirmed by water contact angle measurements. Furthermore, as CHMA amount increased, gel content slightly decreased, while sol molecular weight (Mw ) of the polymer increased. Finally, it was observed that loop tack decreased, while shear strength increased with the incorporation of CHMA. 180° peel strength of the PSA initially increased and then decreased with the addition of CHMA from 0 to 30 wt%, with a maximum value at 10 wt%.