摘要:
Hindered phenolic antioxidants had been well recognized and widely used to improve the performance against thermal oxidative degradation of polyolefin composites.However,the low molecular weight antioxidants have a tendency to migrate from polyolefin products,which does not only directly reduce the performance against thermal oxidative aging of polyolefin and its products,but also pollutes food and medicine in the polypropylene package because of its toxicity.Thus,it is important to develop antioxidants with high-performance,long-durability,and large-resistance against migration.To date,three main approaches have been explored:(i) Increasement of molecular weight,increasing the molecular weight of antioxidants to enhance the structure stability and the resistance towards migration;(ii) Immobilization,immobilizing the antioxidants on/in inorganic substrate to enhance the dispersion and the capacity against migration;(iii) Intercalation into inorganic matrix,intercalating low molecular weight antioxidants into the interlayer region of layered host to enhance anti-migration property based on the host-guest interaction.%受阻酚类抗氧剂在改善聚烯烃复合材料抗热氧老化性能方面已得到广泛认可和应用,但其小分子量分子化合物,由于分子量较低,在聚烯烃及其制品中存在易挥发、易迁移和易抽提等致命缺陷,不仅直接降低聚烯烃及其制品的抗热氧老化效果,而且因其自身的毒性严重影响与之接触的食品或药品安全,因此,可控设计具有耐迁移性的高效持久型抗氧剂具有重要意义.目前主要有三种方法解决这些问题:一是高分子量化,通过提高相对分子质量,增强抗氧剂结构稳定性,延缓迁移;二是固载化,通过无机粒子固载抗氧剂,提高其分散性和耐迁移性;三是插层组装,以低相对分子质量抗氧剂为客体,通过插层组装技术构筑插层结构有机-无机复合型抗氧剂,通过主体-客体相互作用的锚定效应有效抑制抗氧剂的迁移性,从而获得耐迁移高效持久的聚烯烃抗氧剂.