PVC热稳定剂氰尿酸锌的制备及性能研究

以氧化锌和氰尿酸为原料,在弱酸性条件下制备了氰尿酸锌热稳定剂。通过红外光谱分析和X射线衍射对合成产物进行了表征分析。热重分析表明,氰尿酸锌作为PVC热稳定剂能钝化PVC链上的不稳定结构,吸收释放的氯化氢气体,抑制PVC的自催化作用,有效减缓PVC的热降解。通过静态刚果红测试、烘箱热老化测试和动态流变测试,测定了氰尿酸锌作为PVC热稳定剂的热稳定性能。结果表明:热稳定剂添加量为PVC的0.3%(质量分数)时,相比于硬脂酸锌,氰尿酸锌的热稳定性能更好,此时添加氰尿酸锌的PVC热稳定时间为18min,约为加硬脂酸锌热稳定时间的2倍;氰尿酸锌作为PVC热稳定剂的热稳定性能明显优于传统的硬脂酸锌热稳定剂,氰尿酸锌还能有效延长"锌烧"现象,与PVC有良好的相容性和润滑性。

Study on preparation and performance of zinc cyanurate thermal stabilizer for PVC

The heat stabilizer Zinc cyanurate is prepared with zinc oxide and cyanuric acid as raw materials under the condition of weak acid. The product is characterized by FTIR and X-ray diffraction. Thermogravimetric analysis shows that zinc cyanurate as heat stabilizer can passivate unstable structures in PVC chain, absorb hydrogen chloride gas, and inhibit self catalytic of PVC, which effectively slow the thermal degradation of PVC. The thermal stability performance of zinc cyanurate as the thermal stabilizer of PVC is investigated by static Congo red test, dryer thermal ageing test and dynamic rheological test. It is found that when the mass of heat stabilizer is 0.3% of PVC, the thermal stability of zinc cyanurate is better compared to that of zinc stearate, and the thermal stability time of PVC with zinc cyanurate is 18 min, nearly two times that of PVC with zinc stearate; the thermal stability of zinc cyanurate for PVC is superior to that of traditional zinc stearate, and zine cyanurate can prolong the zinc burning phenomnon; zinc cyanurate and PVC have good compatibility and lubricity.