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，使用不同浓度（0 至 1% wt.）的基于偶氮二甲酰胺的化学发泡剂 (CBA)，通过滚塑生产发泡再生高密度聚乙烯 (rHDPE) 部件。从生产的样品中，进行了完整的形态、热和机械表征。形态学分析显示细胞平均大小逐渐增大，而细胞密度随着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和热导率。尽管增加 CBA 含量会降低拉伸和弯曲性能，但冲击强度显示出与泡孔密度相似的趋势，最佳 CBA 含量约为 0.1% wt。最后，还通过压缩成型生产了整洁的 rHDPE 样品。结果表明滚塑和压塑性能之间的差异可以忽略不计，表明选择了最佳滚塑条件。这些结果证实了使用 100% 回收聚合物生产滚塑泡沫部件的可能性。