Abstract Thermoplastic elastomer from ethylene vinyl acetate (EVA) was blended with a biodegradable polymer, poly(lactic acid) (PLA), to develop ecofriendly EVA/PLA foams. The thermal and mechanical properties and the morphologies of the blends with various PLA contents between 0 and 40% were investigated. The rheological properties during gel formation were monitored via in-situ through the evolution of torque with curing time. The EVA/PLA blends showed a two-phase morphology made of a continuous EVA matrix and micron or submicron nodules, and also increased the tensile strength and modulus, as well as hardness, with the increase of the added PLA content. This should be attributed to the micronic dispersion of the rigid PLA in the elastic EVA matrix. The foam samples containing below 30% of PLA exhibited a similar cell structure and foaming ratio to the pure EVA; however, the cell size and foaming ratio gradually reduced with the increase of the added PLA content.

中文翻译：

---

乙烯醋酸乙烯酯 (EVA)/聚乳酸 (PLA) 混合物及其泡沫

摘要 乙烯醋酸乙烯酯 (EVA) 的热塑性弹性体与可生物降解的聚合物聚乳酸 (PLA) 共混，以开发环保的 EVA/PLA 泡沫。研究了 PLA 含量在 0% 到 40% 之间的共混物的热性能和机械性能以及形态。凝胶形成过程中的流变特性通过扭矩随固化时间的演变通过原位监测。EVA/PLA 共混物显示出由连续 EVA 基体和微米或亚微米结节组成的两相形态，并且随着添加的 PLA 含量的增加，拉伸强度和模量以及硬度也增加。这应该归因于刚性 PLA 在弹性 EVA 基体中的微分散。含有低于 30% PLA 的泡沫样品表现出与纯 EVA 相似的泡孔结构和发泡率；然而，随着PLA含量的增加，泡孔尺寸和发泡率逐渐减小。