ABSTRACT
Adhesives based on a polyurethane blended with a series of styrene–butadiene rubber (SBR) latexes have been used to bond joints of vulcanized rubber (R) and of acrylonitrile–butadiene–styrene (ABS). It was shown that the bond strength generated was strongly dependent on the acid level and the gel content of the SBR additive. Bond characteristics were time-dependent. Aging in an inert environment raised bond strengths, apparently due to the ability of phase-separated polyurethanes to restructure at an interface. In aggressive humid media bond strengths decreased, the effect being inversely related to initial bond strengths. An estimate may be made of initial bond strengths needed to resist aging losses in the aggressive medium.
