Peykova, Yana, et al. International Journal of Adhesion and Adhesives 34 (2012): 107-116.
Statistical butyl acrylate-methyl acrylate (BA/MA) copolymer functions as a pressure-sensitive adhesive (PSA) whose adhesion performance is governed by substrate surface energy, copolymer composition, and crosslinking density.
Experimental Protocol: BA/MA copolymers (79.7/20 w/w ratio) with molecular weights of 54,000, 192,000, and 600,000 g/mol are synthesized via radical solution polymerization. Additional comonomers including hydroxyethyl acrylate, methyl methacrylate, and acrylic acid are incorporated at 5 to 10% w/w. Probe tack tests employ flat-ended stainless steel probes (5 mm diameter) with surface roughness (Ra) of 2.9 and 291.7 nm, at a contact force of 10 N for 1 second and a withdrawal rate of 0.1 mm/s at 22 °C.
Performance Evaluation: Stress peak values range from 0.5 to 2.0 MPa depending on substrate surface energy and copolymer composition. Tack values reach up to 200 J/m2 on high-energy surfaces. Incorporation of acrylic acid increases the shear modulus and tack by 50 to 100% compared to the base BA/MA copolymer. Crosslinking at 100 mJ/cm2 UV dose transitions the failure mode from cohesive to adhesive. Cavity growth rate on rough surfaces decreases significantly with increasing shear modulus, while on smooth surfaces it is insensitive to viscoelastic properties.
Hu, Wei, et al. Journal of Materials Chemistry C 2.9 (2014): 1658-1666.