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 Stability of PVC
杜桂芳 1赵金钢 1柳召刚 1陈明光 2黄旭博 1杨羽轩 1胡艳宏 1吴锦绣1
作者信息
- 1. 内蒙古科技大学材料与冶金学院,内蒙古包头 014010;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
- 2. 内蒙古科技大学材料与冶金学院,内蒙古包头 014010;包头稀土研究院,内蒙古包头 014010
- 折叠
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(Ca2+)∶n(La3+)=3∶1,水热温度170 ℃,水热时间8 h,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87 min.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.
Abstract
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 sta-bility of Ca-La-LDHs were studied.The best synthesis conditions were obtained:n(Ca2+)∶n(La3+)=3∶1,170 ℃ of hydrothermal temperature,8 h of hydrothermal time.The products were characterized by FTIR,thermal anal-ysis,scanning electron microscopy and XRD analysis.The effect of rare earth hydrotalcite on the thermal stabili-ty 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 HCl 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Key words
lanthanum/hydrotalcite-like/polyvinyl chloride/thermal stability引用本文复制引用
基金项目
国家自然科学基金重点项目(51634005)
出版年
2024
NETL
NSTL
万方数据