Effect of Mold Temperature on the Impact Behavior and Morphology of Injection Molded Foams Based on Polypropylene Polyethylene–Octene Copolymer Blends

Polymers

Cristina Saiz-Arroyo¹  Santiago Muñoz-Pascual²  MiguelAngel Rodriguez-Perez²  Eduardo Lopez-Gonzalez² 

[1] CellMat Technologies S.L., Paseo de Belen 9-A (CTTA Building), 47011 Valladolid, Spain;Cellular Laboratory (CellMat), Universidad de Valladolid, 47011 Valladolid, Spain;

关键词: polypropylene;    POE;    foam;    impact strength;    elastomer morphology;    crystalline morphology;    cellular structure;   

DOI  :  10.3390/polym11050894

来源: DOAJ

【 摘 要 】

In this work, an isotactic polypropylene (PP) and a polyethylene–octene copolymer (POE) have been blended and injection-molded, obtaining solids and foamed samples with a relative density of 0.76. Different mold temperature and injection temperature were used. The Izod impact strength was measured. For solids, higher mold temperature increased the impact resistance, whereas in foams, the opposite trend was observed. In order to understand the reasons of this behavior, the morphology of the elastomeric phase, the crystalline morphology and the cellular structure have been studied. The presence of the elastomer near the skin in the case of high mold temperature can explain the improvement produced with a high mold temperature in solids. For foams, aspects as the elastomer coarsening in the core of the sample or the presence of a thicker solid skin are the critical parameters that justify the improved behavior of the materials produced with a lower mold temperature.

【 授权许可】

Unknown