2017 Volume 53 Issue 8 Pages 268-275
Pressure-sensitive adhesive (PSA) is a typical viscoelastic material, therefore the test rate dependenciesof tensile and adhesion properties were compared. For this purpose, the effects of both crosslinking agentconcentration and tensile test rates on the tensile properties of PSA composed of crosslinked poly(n-butylacrylate-acrylic acid) with an acrylic acid content of 5 wt% were determined. Tensile test rates ranging from1.7 × 10-2 to 5 mm･s-1 were applied, and the resulting data were compared with the adhesion properties ofthe PSA. The 100% modulus was found to increase with increasing crosslinking agent content and with fastertensile test rates. In contrast, the maximum stress and the elongation at break showed maximum values atspecific crosslinking agent levels, and these peak values shifted depending on the rate. The 90º peel strengthof the PSA was measured over the peel rate range from 1.7 × 10-2 to 5 mm･s-1, and was observed to increasewith greater degrees of crosslinking and with faster peel rates under those conditions associated with cohesivefailure. Conversely, the peel strength increased with faster peel rates, whereas it decreased with an increase incrosslinking degree under the condition of interfacial failure. The higher 100% modulus lowered the interfacialadhesion. The 100% modulus affected strongly on the peel strength.
