Failures caused by environmental stress cracking (ESC) in polymers, especially amorphous ones, pose substantial concerns for their safety issues and long-term applications. Herein, we proposed a strategy through volume pulsation injection molding (VPIM) to delay the cracking by extending the solvent diffusion path and modulating the crystallization behavior of semi-crystalline polymers. High-impact polystyrene (HIPS) was employed as a model material with high-density polyethylene (HDPE) as the ESC resistor. The as-prepared blend after the VPIM treatment can suffer 48 h of loaded oil immersion, which can be hardly achieved for reference samples prepared via the conventional injection molding (CIM) method and pure HIPS. Through in-depth investigations of the oil-stress treatment-induced ESC behaviors, we demonstrated the improvement in the anti-ESC performance can be attributed to the in-situ fiberization of HDPE during VPIM. This work will open new possibilities for improving the anti-ESC performance of polymers in practical applications.

中文翻译：

---

半结晶聚合物体积脉动注射成型提高非晶聚合物的抗环境应力开裂性能


聚合物（尤其是非晶态聚合物）中由环境应力开裂（ESC）引起的失效对其安全问题和长期应用构成了重大担忧。在此，我们提出了一种通过体积脉动注射成型（VPIM）的策略，通过延长溶剂扩散路径和调节半结晶聚合物的结晶行为来延迟开裂。采用高抗冲聚苯乙烯 (HIPS) 作为模型材料，并采用高密度聚乙烯 (HDPE) 作为 ESC 电阻。 VPIM处理后制备的共混物可以承受48小时的负载油浸，这是通过传统注射成型（CIM）方法和纯HIPS制备的参考样品很难达到的。通过深入研究油胁迫处理引起的 ESC 行为，我们证明抗 ESC 性能的提高可归因于 VPIM 过程中 HDPE 的原位纤维化。这项工作将为提高聚合物在实际应用中的抗ESC性能开辟新的可能性。