钙镧类水滑石的合成及对PVC热稳定性能的影响  

Synthesis of Calcium Lanthanum Hydrotalcite and Its Effect on Thermal Stabilityof PVC

作　　者：杜桂芳 赵金钢 柳召刚[1,2] 陈明光 黄旭博 杨羽轩 胡艳宏 吴锦绣[1,2] Du Guifang;Zhao Jingang;Liu Zhaogang;Chen Mingguang;Huang Xubo;YangYuxuan;Hu Yanhong;Wu Jinxiu(School of Materials and Metallurgy,Inner Mongolia University of Science and Technology,Baotou 014010,China;Key Laboratory of Green Extraction and Efficient Utilization of LREE Resources,Ministry of Education,Key Laboratory of Rare Earth Hydrometallurgy and Light Rare Earth Application of Inner Mongolia Autonomous Region,Baotou 0140104,China;Baotou Rare Earth Research Institute,Baotou 014010,China)

机构地区：[1]内蒙古科技大学材料与冶金学院,内蒙古包头014010 [2]轻稀土资源绿色提取与高效利用教育部重点实验室,内蒙古自治区稀土湿法冶金与轻稀土应用重点实验室,内蒙古包头014010 [3]包头稀土研究院,内蒙古包头014010

出　　处：《中国稀土学报》2024年第2期339-348,I0005,共11页Journal of the Chinese Society of Rare Earths

基　　金：国家自然科学基金重点项目(51634005)资助。

摘　　要：用水热法制备了钙镧类水滑石(Ca-La-LDHs),研究了阳离子配比、水热时间和水热温度对Ca-La-LDHs的结构及PVC热稳定性能的影响,得到最佳的合成条件为:n(Ca^(2+)):n(La^(3+))=3:1,水热温度170℃,水热时间8h,并对最佳条件产物进行了XRD及红外光谱、热分析、SEM表征。通过刚果红实验、高温老化实验、转矩流变实验、拉伸实验和电导率实验,研究了Ca-La-LDHs对PVC的热稳定性能、塑化性能及力学性能的影响,结果表明,钙镧类水滑石能显著提升PVC的热稳定性能,其静态热稳定时间为87min。Ca-La-LDHs样品降低了平衡转矩,提升了动态热稳定时间,显著延缓了PVC释放HCl的速率,从而提升了动态热稳定性。Ca-La-LDHs提升了PVC板材的抗拉强度和断裂伸长率。Ca-La-LDHs热稳定剂阻碍了PVC中的C-Cl和C-H键的断裂,抑制HCl和C=C键的生成,减少了HCl对PVC降解的进一步催化。Calcium-lanthanum hydrotalcites(Ca-La-LDHs)were prepared by hydrothermal method.The effect of different cation ratios,hydrothermal time and hydrothermal temperature on the synthesis and their thermal stability of Ca-La-LDHs were studied.The best synthesis conditions were obtained:n(Ca^(2+)):n(La^(3+))=3:1,170℃of hydrothermal temperature,8 h of hydrothermal time.The products were characterized by FTIR,thermal analysis,scanning electron microscopy and XRD analysis.The effect of rare earth hydrotalcite on the thermal stability and plasticization performance of PVC was studied through the Congo red experiment,high temperature aging experiment,torque rheology experiment,tensile experiment and electrical conductivity experiment.The results show that under the optimal preparation conditions,Ca-La-LDHs thermal stabilizers can significantly improve the thermal stability of PVC,and the static thermal stability time is 87 min.The Ca-La-LDHs sample reduces the equilibrium torque,increases the dynamic thermal stability time,and significantly delays the release rate of HCI from PVC,thereby improving the dynamic thermal stability.Ca-La-LDHs improved the tensile strength and elongation at break of PVC sheets.The Ca-La-LDHs thermal stabilizer hinders the cleavage of C-Cl and C-H bonds in PVC,which inhibits the generation of HCl and C=C bonds,then reducing the further catalysis of PVC degradation by HCl.

关 键 词：镧 类水滑石 聚氯乙烯 热稳定性能 

分 类 号：TQ325.3[化学工程—合成树脂塑料工业]