锌镁铝水滑石的制备条件对PVC热稳定性的影响

摘要

ZnMgAl-LDHs was prepared by hydrothermal synthesis method with zinc nitrate, magnesium nitrate, aluminum nitrate, sodium hydroxide and sodium bicarbonate as raw materials, and the XRD characterization of synthetic products was carried out. The prepared ZnMgAl-LDHs was used in PVC heat stabilizer. The thermal stability of PVC was evaluated by plate vulcanization method. the influence of preparation conditions with n(Zn)(Mg) and alkaline etc. on the thermal stability of PVC were investigated. The results show that when n(M2+)(M3+)=2, n(Zn2+)(Mg2+)=1, n(NaHCO3)(Al3+)=1.1, n(NaOH)/(2nM2++3nM3+)=0.9, the reaction temperature is 90 ℃, the reaction time is 24 h, the prepared ZnMgAl-LDHs has good initial colorability and long-term thermal stability of PVC.%以硝酸锌、硝酸镁、硝酸铝、氢氧化钠和碳酸氢钠为原料,采用水热合成法制备了锌镁铝水滑石,并对合成产物进行XRD表征.将所制得的镁铝锌水滑石用于PVC热稳定剂中,采用平板硫化法评价其对PVC的热稳定性能,考察锌铝摩尔比、碱量等水滑石制备条件对PVC热稳定性能的影响.结果表明:当n(M2+)(M3+)=2,n(Zn2+)(Mg2+)=1, n(NaHCO3)(Al3+)=1.1, n(NaOH)/ (2nM2++3nM3+)=0.9,反应温度为90 ℃,反应时间为24 h时,合成的锌镁铝水滑石对PVC具有较好的初期着色性能、长期热稳定性能.