Cell structure-impact property relationship of polypropylene/thermoplastic elastomer blend foams

[摘要] The purpose of the present study was to investigate the effect of cellular structure on the impact strength ofpolypropylene/polyolefin elastomers blend foams produced by the continuous extrusion process. To create different cellsizes, two chemical blowing agents were employed: azodicarbonamide and sodium bicarbonate. Sodium bicarbonate createdfoams with bigger cell size and cell wall thickness than azodicarbonamide. The impact strength of the neat and blend foamswere studied and correlated to the foam properties and structure. It was observed that the impact strength of blend foamswas directly related to the concentration of polyolefin elastomers (POE). Increasing POE by up to 30 wt% increased thefoam impact strength by more than 400%. On the other hand, Increasing POE content caused the cell size and cell wallthickness to be reduced. Moreover, an attempt has been made to establish a relationship between the impact strength andcellular structural parameters. It was found that in the blend foams with higher cell wall thickness the rough fracture of thecell walls was intensified and in turn, the impact strength of the foams improved further.

[学科分类] 生物科学（综合）

[关键词] polymer blends and alloys;foam;polypropylene;impact strength;thermoplastic elastomer