Mastic of polymer-modified bitumen and poly(vinyl chloride) wastes



Micronized poly(vinyl chloride) (PVC) pipe waste has been employed as a soft filler in making bituminous products. The binder used in this study consists of styrene–butadiene–styrene-modified bitumen, isocyanate production waste, and an antioxidant. The time-dependent properties of these binders were assessed by constructing a master curve using frequency multiplexing. A plateau at intermediate and low frequencies in the storage modulus curves of modified bitumen implies the existence of molecular association among the constituents compared to neat bitumen. The enhanced adhesion between the PVC particles activated by H2O2 and the bitumen was verified in terms of bitumen anchorage onto particles after washing in hot toluene. Confirmation of these effects can also be seen by increased stiffness of the bituminous mix with the activated particles over that with nonactivated particles. Consequently, a suitable mastic composition consisting of these activated coarse and micronized particles, limestone dust, and polymeric bituminous binder has been achieved. The results indicate that the optimized mix can be used as waterproof roof mastic as an alternative to conventional bituminous mastic. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 1347–1356, 2003