聚烯烃热氧老化机理及寿命预测研究进展

doi:10.16085/j.issn.1000-6613.2024-1265

摘要/Abstract

摘要：

聚烯烃材料是一类应用广泛的合成塑料，由于在使用过程中容易暴露在热空气和氧环境中产生热氧老化现象，导致材料耐久性降低，进而影响其服役寿命。本文介绍了聚烯烃材料的热氧老化机理，其中氢原子转移反应是分析老化机理的关键。讨论了不同抗氧剂的防护机理和优缺点，明晰了抗氧剂对老化进程的影响。分别从表观性能、热性能、机械性能三个方面阐述了热氧老化引起的聚烯烃材料特性的变化。分析了聚烯烃材料的寿命预测方法，包括基于单一性能参数和基于多性能参数的寿命预测方法。最后，针对未来的聚烯烃热氧老化研究工作，提出了从原子尺度建立完整老化理论体系、建立微观结构与宏观性能之间的量化关系和结合多性能参数提高寿命预测准确度等建议，以期为聚烯烃材料的寿命调控提供理论参考。

关键词: 热氧老化, 老化机理, 自由基, 理化特性, 寿命预测

Abstract:

Polyolefin materials, a widely used class of synthetic plastics, are susceptible to thermal-oxidative aging due to their exposure to hot air and oxygen during usage. This aging process can reduce material durability, ultimately affecting their service life. In this paper, the thermal-oxidative aging mechanism of polyolefin materials was introduced with a particular focus on the hydrogen atom transfer reaction, which served as the pivotal process in elucidating the aging mechanism. The protection mechanism, advantages and limitations of various antioxidants were discussed, elucidating their impact on the aging process. Thermal-oxidative aging of polyolefin materials led to alterations in their properties, which can be categorized into three distinct aspects: apparent changes, thermal properties and mechanical behaviors. The analysis encompassed life prediction methodologies for polyolefin materials, categorizing them into those utilizing a single performance metric and those incorporating multiple performance metrics. Finally, for future research on polyolefin thermal-oxidative aging, this work proposed several suggestions aimed at enhancing the theoretical foundation for lifespan regulation of these materials, including developing a comprehensive aging theory from the atomic level, quantifying the correlation between microstructures and macroscopic properties, and integrating multiple performance metrics to refine lifetime prediction accuracy.

Key words: thermal-oxidative aging, aging mechanism, radical, physicochemical properties, life prediction

中图分类号:

TQ325

李雪娇, 姜宁, 刘鑫浩, 李迪, 徐家川. 聚烯烃热氧老化机理及寿命预测研究进展[J]. 化工进展, 2025, 44(9): 5075-5091.

LI Xuejiao, JIANG Ning, LIU Xinhao, LI Di, XU Jiachuan. Research progress of thermal-oxidative aging mechanism and life prediction of polyolefin[J]. Chemical Industry and Engineering Progress, 2025, 44(9): 5075-5091.

图/表 12

图1 聚烯烃自氧化机理[16, 22]

图2 聚烯烃抗氧剂机理[31]

图3 聚烯烃表观性能的变化[39, 41-42]

图4 材料表观性能随老化的变化[43-44]

图5 聚烯烃热性能随热氧老化的变化[46-49]

图6 热氧老化条件对聚烯烃材料机械性能的影响[48, 55, 57, 59]

图7 由弹性模量预测PVC寿命[66]

图8 不同表征方法寿命预测的一致性[71]

图9 PE管材OIT数据对数图与预测曲线[74]

图10 材料非均相氧化现象[41, 76]

图11 ANN示意图与聚合物老化寿命预测系统示意图[81]

表1 不同寿命预测方法适用条件与优缺点对比

寿命预测方法	适用条件	优势	局限性
基于单一机械性能参数	适用范围广泛	直观性、标准化测试方法、失效模式明确、无需复杂的化学分析	忽略DLO效应、预测周期长
基于单一微观产物参数	已知老化机理	灵敏度高、预测周期短	检测技术要求高、老化机理复杂
基于人工神经网络法	机理不明、数据量大	多变量输入、准确度高、鲁棒性强，灵活性高	数据依赖性强

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