Aproveitamento de resíduos de borracha na tenacificação do poliestireno.

Abstract

The performance of rubber (styrene-butadiene copolymer-SBR) residues from shoe soling and tire industries as impact modifiers to polystyrene (Estireno do Xordeste-EDX-849) was investigated. Mechanical properties of compression moulded samples were determined as a function of processing, residue's nature, content and average particle size. The results obtained were compared with that of a commercially available high impact polystyrene (Estireno do Xordeste-EDX-492). Subjected to the same experimental conditions. The results showed that: 1) the residues employed do perform as impact modifiers to polystyrene: 2) twin-screw extrusion was the most effective blending method: 3) properties optimization was obtained at 20°o ww residue content and was independent of the residue's nature: 4) for the particle sizes investigated the best properties were obtained for the 300-180um range: 5) the best impact properties were imparted by shoe soling residues: 6) high impact polystyrene exhibited better impact properties than those of the blends under study which shows that these could only be employed for medium-bnpact applications; 7) a preliminary study showed that injection moulding yields products with overall better mechanical properties than compression moulded ones.