Studies on morphology and mechanical properties of PP/HIPS blends from postconsumer plastic waste

Abstract

ABSTRACT:The aim of this work was to study the compatibilizing effect of the triblock copolymer poly(styrene-bethylene-co-butylene-b-styrene) (SEBS) on the morphology and mechanical properties of virgin and recycled polypropylene/high-impact polystyrene (PP/HIPS) blends. The components of the blend were obtained from municipal plastics waste (MPW), with the PP obtained from blue mineral water bottles, symbolized as PP b , and the HIPS from disposable cups. These materials were preground, washed only with water, dried with hot air, and ground again (PP b ) or agglutinated (HIPS). Blends of PP b and HIPS in three weight ratios (6:1, 6:2, and 6:3) were prepared, and three concentrations of SEBS (5.0, 6.0, and 6.7% w/w) were used for investigations of its compatibilizing effect. Scanning electron microscopy (SEM) showed that SEBS reduced the diameter of HIPS dispersed particles that were globular and fibril shaped, along with improving the adhesion between the dispersed phase and the matrix. On the other hand, SEBS interactions with PP b and HIPS influenced the mechanical properties of the compatibilized PP b /HIPS/SEBS blends. The optimal concentration of SEBS was 5 wt % for application to composite films with similar characteristics to synthetic paper.

Mechanical and Thermal Characterization of Melt-Filtered, Blended and Reprocessed Post-Consumer WEEE Thermoplastics

“…Table 3 summarizes the main results from the TSE runs of WEEEBR, TBV and TBR under different processing conditions. Both E and σy tend to be slightly higher in the recycled materials than in the virgin materials, as has also been observed previously for HIPS, PP and compatibilised blends of these two [30]. No significant differences were found in the elongation at yield (εy), except perhaps for TBV processed at 60 rpm and T1 that was the most ductile material, and exhibited a In the TSE reprocessing of WEEEBR, the screw rotation rate and barrel temperature were varied independently in order to study their influence on the mechanical properties of the collected and reprocessed blend.…”

Efeito da adição de diferentes copolímeros em blendas HDPE/HIPS pós-consumo: morfologia de fases e propriedades térmicas

“…Considerando uma pesquisa mais ampla sobre filmes especiais obtidos com plásticos de resíduo urbano desenvolvida por este Grupo, blendas de poliolefinas e HIPS pós-consumo foram estudadas quanto ao efeito da adição de agentes compatibilizantes sobre as propriedades das blendas e dos filmes obtidos com as mesmas [2,[17][18][19] . No presente trabalho, foram realizados estudos comparativos do efeito da adição de copolímeros multibloco SBS e linear SEBS, especificamente em blendas de HDPE e HIPS pós-consumo.…”

“…O procedimento para a recuperação mecânica da matéria prima foi o convencional descrito em publicações anteriores do grupo [2,18,19] . Os agentes compatibilizantes comerciais SEBS Kraton® G e SBS Styrolux® 684D, são da Kraton e da Basf, respectivamente.…”

“…As composições HDPE/HIPS estudadas foram 100/0, 80/20, 60/40, 40/60, 20/80 e 0/100 sem e com copolímero, o qual foi fixado em 7,5%, baseado em resultados obtidos em trabalhos anteriores [17][18][19] . Para a blenda HDPE/HIPS, na referência [19] , os resultados foram melhores com 10% em peso de copolímero do que com 5%, entretanto não se analisou uma concentração intermediária, o que justificou adição de 7,5% no presente trabalho.…”

Crystallization and dynamic mechanical properties of polypropylene/polystyrene blends modified with maleic anhydride and styrene

“…The morphological, viscosity, and interfacial tension results showed that SEBS is a better compatibilizer for PP/PS blends than SBS. Santana and Campomanes 15,16 studied the compatibilizing effect of SEBS on the morphology and mechanical properties of virgin and recycled PP/HIPS blends. SEBS reduced the diameter of dispersed HIPS particles and improved the adhesion between the dispersed phase and the matrix.…”