硬脂酸锌改性水滑石热稳定剂的制备及应用

Preparation and Application of Zinc Stearate Modified Hydrotalcite as Thermal Stabilizer for PVC

以镁铝碳酸根型水滑石[Mg Al-CO_3-LDH_s(LDHs)]为前驱体,硬脂酸锌(Zn St_2)为改性剂,通过离子交换反应制备硬脂酸锌改性水滑石(LDHs-Zn St_2)。采用XRD、FT-IR、SEM和TG进行表征,并研究其对聚氯乙烯(PVC)热稳定性能的影响。结果表明,硬脂酸锌成功插层到水滑石层间,层间距由0.78 nm增加到1.35 nm,热失重温度向高温移动,失重率增加。与LDHs和Zn St_2的复配热稳定剂相比,LDHs-Zn St_2能显著改善PVC的初期着色性和长期热稳定性能,二者之间有较好的协同作用。

The zinc stearate modified hydrotalcite （LDHs-ZnSt2 ） was prepared by ion exchange reaction using MgAl-CO3-LDHs （LDHs） as the precursor and zinc stearate as the modifier. The synthesized materials were characterized by X-ray diffractometer, Fourier transform infrared spectrometer, scanning electron microscope and thermogravimetry （TG）. And the effects of LDHs-ZnSt2 on the thermal stability of polyvinyl chloride （PVC） were investigated. The results show that ZnSt2 is successfully intercalated into the interlayer of LDHs, and the interlayer distance enlarges from 0.78 nm to 1.35 nm. From TG analysis, the mass loss rate of LDHs-ZnSt2 increases more greatly than that of the precursor, and the second weight loss stage occurs toward higher temperature region. Due to the better synergistic effect between LDHs and ZnSt2 , the LDHs-ZnSt2 could improve both the initial coloration and long-term thermal stability of PVC significantly.