The emergence of expanded thermoplastic polyurethane foam beads (ETPU) has expanded the application range of polymer foam materials. However, most of the prepared bead foam products suffer from high shrinkage rate, high density, and poor interfacial bonding, severely affecting the mechanical stability and lightweighting of the products. Herein, this study constructed thermoplastic polyurethane/polybutylene succinate (TPU/PBS) bead blend foams with a segregated microcellular network structure (SMNS) for the first time, where the TPU/PBS continuous phase formed the SMNS and the bead phase was consisted of TPU foam beads. The results showed good interfacial bonding between the continuous and bead phases. By adding PBS to the continuous phase, the shrinkage percentage of TPU/PBS bead blend foam decreased from 79.19 % to 67.31 %, reduced by 15.0 %. In addition, the foam expansion ratio gradually decreased with increasing PBS content, dropping from 12.07 to 9.03. Moreover, TPU/PBS bead blend foams exhibited good energy absorption and mechanical stability without sacrificing thermal insulation performance. This work effectively reduced the shrinkage of TPU based foam materials, offering a simple and economical solution for the preparation of dimensionally stable, well-interfaced, and lightweight polymer foams.

中文翻译：

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轻松制造轻质高膨胀 TPU/PBS 珠粒混合泡沫，具有隔离微孔网络，可减少收缩并增强界面粘合


发泡热塑性聚氨酯泡沫珠粒（ETPU）的出现扩大了高分子泡沫材料的应用范围。然而，所制备的珠粒泡沫产品大多存在收缩率高、密度高、界面结合差等问题，严重影响了产品的机械稳定性和轻量化。在此，本研究首次构建了具有分离微孔网络结构（SMNS）的热塑性聚氨酯/聚丁二酸丁二醇酯（TPU/PBS）珠粒共混泡沫，其中TPU/PBS连续相形成SMNS，珠粒相由TPU组成泡沫珠。结果表明连续相和珠状相之间具有良好的界面结合。通过在连续相中添加PBS，TPU/PBS珠粒共混泡沫的收缩率从79.19%下降到67.31%，降低了15.0%。此外，随着PBS含量的增加，泡沫膨胀倍数逐渐降低，从12.07降至9.03。此外，TPU/PBS珠粒共混泡沫在不牺牲隔热性能的情况下表现出良好的能量吸收和机械稳定性。这项工作有效降低了TPU基泡沫材料的收缩率，为制备尺寸稳定、界面良好的轻质聚合物泡沫提供了一种简单且经济的解决方案。