Dou Yao, Rodrigue Denis
Department of Chemical Engineering and CERMA, Université Laval, Quebec City, QC, Canada.
J Cell Plast. 2022 Mar;58(2):305-323. doi: 10.1177/0021955X211013793. Epub 2021 Apr 29.
In this study, foamed recycled high density polyethylene (rHDPE) parts were produced by rotational molding using different concentration (0 to 1% wt.) of a chemical blowing agent (CBA) based on azodicarbonamide. From the samples produced, a complete morphological, thermal and mechanical characterization was performed. The morphological analysis showed a gradual increase in the average cell size, while the cell density firstly increased and then decreased with increasing CBA content. As expected, increasing the CBA content decreased the foam density as well as the thermal conductivity. Although increasing the CBA content decreased both tensile and flexural properties, the impact strength showed a similar trend as the cell density with an optimum CBA content around 0.1% wt. Finally, neat rHDPE samples were also produced by compression molding. The results showed negligible differences between the rotomolded and compression molded properties indicating that optimal rotomolding conditions were selected. These results confirm the possibility of using 100% recycled polymers to produce rotomolded foam parts.
在本研究中，采用旋转模塑工艺，使用基于偶氮二甲酰胺的不同浓度（0至1%重量）的化学发泡剂（CBA）制备了发泡再生高密度聚乙烯（rHDPE）部件。对所制备的样品进行了完整的形态、热性能和力学性能表征。形态分析表明，平均泡孔尺寸逐渐增大，而泡孔密度随着CBA含量的增加先增大后减小。正如预期的那样，增加CBA含量会降低泡沫密度以及热导率。尽管增加CBA含量会降低拉伸性能和弯曲性能，但冲击强度与泡孔密度呈现相似的趋势，在CBA含量约为0.1%重量时达到最佳。最后，还通过压缩模塑制备了纯rHDPE样品。结果表明，旋转模塑和压缩模塑性能之间的差异可忽略不计，这表明选择了最佳的旋转模塑条件。这些结果证实了使用100%回收聚合物生产旋转模塑泡沫部件的可能性。
