Journal of Adhesion Science and Technology, Vol.16, No.13, 1765-1780, 2002
MEK wiping prior to chlorination to improve the adhesion of vulcanized SBR rubber containing paraffin wax
In this study, it was shown that the degree of effectiveness produced by halogenation with trichloroisocyanuric acid (TCI) was influenced by previous methyl ethyl ketone (MEK) wiping of a synthetic vulcanized styrene-butadiene rubber (R2) surface. The MEK wiping of the R2 rubber surface prior to chlorination with TCI removed the paraffin wax layer from the surface, which favoured the chlorination and oxidation reactions of the rubber. Chlorination with TCI decreased the contact angle values (increased the wettability) mainly due to the creation of C-Cl and C=O moieties, as well as roughness. The amount of these chemical moieties increased when the MEK wiping was applied prior to chlorination, so higher degrees of chlorination and oxidation were obtained on the R2 rubber surface. T-peel strength values increased more markedly if the MEK wiping was carried out before chlorination with TCI, in agreement with the higher degree of modifications produced in the R2 rubber surface. In fact, a cohesive failure in the R2 rubber was obtained in the adhesive joint produced with MEK wiped + TCI chlorinated R2 rubber.
Keywords:vulcanized rubber;halogenation with trichloroisocyanuric acid;contact angle measurements;ATR-IR spectroscopy;XPS;SEM;peel strength