肉豆蔻酸稀土复合热稳定剂对PVC性能的影响

Effects of Rare Earth Myristate Compound Stabilizer on Thermal Stability of PVC

合成了肉豆蔻酸镧、肉豆蔻酸铈、肉豆蔻酸钕3种稀土热稳定剂,采用刚果红法分别测试了其与硬脂酸锌、季戊四醇、硬脂酸钙之间的协同作用,复配得到了硬质聚氯乙烯(PVC)用新型肉豆蔻酸稀土复合热稳定剂,利用转矩流变仪、动态力学谱仪等考查其对PVC流变性能和力学性能的影响。结果表明,肉豆蔻酸稀土复合热稳定剂具有良好的热稳定性,静态和动态热稳定时间分别约为120、60min,能较好地抑制PVC的初期着色性;复合稀土体系的加工流变性能优于铅盐体系,拉伸强度、断裂伸长率和断裂强度与铅盐体系相当,而冲击强度高于铅盐体系。

Thermal stabilizers, anthanum myristate, cerium myristate, and neodymium myristate for rigid PVC were synthesized, and their synergistic effect with zinc/calcium stearate and pentaerythritol was investigated using Congo red method. Influence of these stabilizers on PVC was determined by means of torque rheometer and dynamic thermal mechanical analyzer. Composite stabilizers were prepared from the myristates and zinc/calcium stearate and/or pentaerythritol. When the composite stabilizers were used, static and dynamic thermal stability time of PVC reached about 120 min and 60min, respectively. The early coloring of PVC was inhibited. The processing performance was also improved. The tensile strength, elongation at break, and fracture strength were similar to those with lead salt system, while the impact strength was higher.