【作者】 张莉；

【导师】 乔辉；

【作者基本信息】 北京化工大学 ， 高分子化学与物理， 2006， 硕士

【摘要】 铅盐和有机锡是PVC常用的热稳定剂，铅盐稳定剂有毒，其使用受到越来越多的限制；有机锡稳定剂安全性较高，但价格昂贵。因此寻找一种安全环保、价格合理的新型稳定剂在PVC的应用中显得十分必要。镁铝水滑石是一种水滑石类镁铝层状双羟基氢氧化物(简称LDHs)，水滑石碱中心可捕捉PVC受热老化释放出的HCl，提高PVC的热稳定性。本文利用镁铝水滑石与铅盐、有机锡复配，并将其复配体系分别应用于PVC糊制品和PVC硬制品中，使用热老化仪、分光测色仪、TG、万能力学试验仪和扭距流变仪对PVC的热老化性能、流变性能进行研究。结果表明，LDHs可作为PVC的热稳定剂，其与有机锡和铅盐复配后体现出较好的协同效应，LDHs／Sn和LDHs／Pb形成的复合稳定剂基本上可以达到相同份数上纯有机锡和纯铅盐的稳定效果；PVC糊制品中，LDHs／Sn=2.5／2.5和LDHs／Pb=3／2的稳定效果最佳；PVC硬制品中，未加钛白粉的PVC体系中，LDHs／Sn=1.0／3.5(质量比)的复合稳定剂的稳定效果优于LDHs／Sn=0／4.5的稳定体系；加钛白粉的PVC体系中，LDHs／Pb=1.5／3.5(质量比)的复合稳定剂稳定效果优于LDHs／Pb=0／5.0稳定体系。LDHs作为一种无机粉体，它的加入对有机物的流变性能影响较大，因此PVC中加入LDHs及其复配体系后流变曲线中平衡扭距上升，加工难度增大。更多还原

【Abstract】 The lead salt stabilizers and organotin stabilizers are often used in PVC to control the degradation of PVC in processing. But lead salt stabilizers are poisonous and organotin stabilizers are expensive even if its higher security. It is necessary to seek a new kind of stabilizers that are secure, protecting environment and cheaper. Mg, Al LDHs is Mg_1-x²⁺Al_x³⁺ layered double hydride （LDH） of the hydrotalcites （LDHs）, which can exhibit thermal stability during PVC aging. In this thesis, application of Mg, Al LDHs/Pb and Mg, Al LDHs /Sn composites in PVC pastes and rigid PVC were investigated. The thermal aging property and rheologic property were studied by using the aging instrument, spectrophotometer, TG, rhometer and universal mechanical testing instrument. The results show that there were both better synergism between Mg, Al LDHs and Pb and between Mg, Al LDHs and Sn. The thermal effect of LDHs/Pb composites and LDHs/Sn composites approach the effect of pure Pb or pure Sn. In PVC paste, LDHs/Sn=2.5/2.5 and LDHs/Pb=3/2（quality ratio） exhibit the best thermal stability. In rigid PVC without TiO₂, the thermal effect of LDHs/Sn=1.0/3.5 is better than the one of LDHs/Sn =0/4.5（quality ratio）. In rigid with TiO₂,LDHs/Pb=1.5/3.5 exhibit更多还原