resumo
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 coumarone-indene 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 mu 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 x 10(4) 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. Differential scanning calorimetry (DSC) and Fourier transform infrared spectroscopy (FTIR) study confirms the miscibility of tackifier and the ENR 25. (C) 2011 Elsevier Ltd. All rights reserved.
palavras-chave
COUMARONE-INDENE RESIN; MOONEY SCORCH TIME; PEEL STRENGTH; SMR L; ACRYLIC COPOLYMER; GUM ROSIN; MISCIBILITY; BLENDS; TACK; TACKIFIER
categoria
Materials Science
autores
Khan, I; Poh, BT
nossos autores
Imran Khan
Bolseiro de pós-DoutoramentoGrupos
agradecimentos
The authors acknowledge the research grant (FRGS) provided by Universiti Sains Malaysia that has resulted in this article.