4th USM-JIRCAS Joint International Symposium: Effect of Molecular Weight and Testing Rate on Adhesion Property of Pressure-Sensitive Adhesives Prepared from Epoxidized Natural Rubber (ENR 25)
authors Imran Khan, B.T. Poh
keywords Adhesion, Epoxidized Natural Rubber, Molecular Weight, Rate of Testing.
abstract The dependence of peel strength and shear strength of epoxidized natural rubber (ENR-25)-based pressure sensitive adhesive on molecular weight and rate of testing was investigated using petro resin as the tackifying resin. Toluene and polyethylene terephthalate (PET) were used as the solvent and substrate respectively throughout the study. A SHEEN hand coater was used to coat the adhesive on the substrate at a coating thickness of 120 m. All the adhesion properties were determined by a Llyod Adhesion Tester operating at different rates of testing. Result shows that peel strength and shear strength increases up to an optimum molecular weight of 6.5×104 of ENR 25. For peel strength, the observation is attributed to the combined effects of wettability and mechanical strength of rubber at the optimum molecular weight, whereas for the shear strength, it is ascribed to the increasing amount of adhesive present in the coating layer which enhances the shear resistance of the adhesive. Peel strength and shear strength also increases with increase in rate of testing, an observation which is associated to the viscoeslastic response of the adhesive.
year published 2011
subject category 4th USM-JIRCAS Joint International Symposium