聚乙烯缆索护套应力-光氧老化开裂的基础研究

项目名称： 聚乙烯缆索护套应力-光氧老化开裂的基础研究

项目编号： No.51273130

项目类型： 面上项目

立项/批准年度： 2013

项目学科： 一般工业技术

项目作者： 任显诚

作者单位： 四川大学

项目金额： 79万元

中文摘要： 通过人工加速张应力-光氧老化模拟实验对聚乙烯缆索护套在应力-光氧老化过程所发生的分子链降解、凝聚态结构变化、微裂纹的产生及发展等微观物理化学变化进行深入研究，探索这些微观结构的变化对老化进程作用的一般规律；研究聚乙烯的分子量及分子量分布、支化度、结晶度等结构及力学性能和耐环境应力开裂性能与聚乙烯护套耐应力光氧老化开裂性能之间的必然联系；并着重研究张应力对聚乙烯光氧老化过程的作用和机理，以及临界张应力（安全应力）的物理本质和与材料结构和性能之间的相互关联；通过成型过程的形态控制获得从表层到制品内部的不同凝聚态结构（结晶度、取向度），研究这些结构在应力光氧老化过程中的变化规律及与制品开裂失效的关系；从而建立聚乙烯护套材料的使用寿命的客观预估方法。

中文关键词： 聚乙烯；护套；应力；光氧降解；开裂

英文摘要： The microscopic physical and chemical changes of artificial accelerated aging polyethylene jacket will be studied under stress and ultraviolet irradiation. And the correlation between the degradation process and the microstructure changes such as chain scission, congregated structure and the formation and evolution of cracks is about to investigated. Furthermore, the effects of molecular weight and molecular weight distribution, branching coefficient, crystallinity, mechanical properties and the properties of environmental stress cracking resistance of polyethylene on the cracking resistance of the jacket are going to be discussed. Moreover, the impact of stress on the photo-oxidative degradation of polyethylene is to be discussed and the mechanism will be studied. In addition, the relationship between the critical stress (safety stress) and the structure and properties of the material will also be investigated. The changes of the congregated structures (crystallinity and branching coefficient) from the surface to the internal of the product, which are formed in different processing conditions, during the stress-photooxidative degradation will be discussed and the role in the cracking failure of the jacket is to be studied as well. Most important of all, a lifetime prediction method for the polyethylene jacket w

英文关键词： polyethylene；jacket；stress；photooxidation；cracking