水滑石对聚氯乙烯性能的影响

Effect of Hydrotalcite on the Properties of Polyvinyl Chloride

采用水滑石(LDHs)和自制铜-有机蒙脱土对聚氯乙烯(PVC)板材进行耐火抑烟性能的改性,研究了LDHs的含量对PVC复合体系阻燃性、热稳定性、流变性能及力学性能的影响。结果表明,随着LDHs含量的增加,对PVC复合体系的极限氧指数、耐热性和烟密度均存在一定程度的影响。其中,极限氧指数提高了3.9%,热变形温度提高了3.8℃,烟密度约下降了6%。热稳定性提高,残炭增加,能够有效降低HCl的产生。塑化扭矩和平衡扭矩的减小,有利于产品的加工。添加合适含量的LDHs能够有效改善体系的力学性能,使拉伸强度提升20%,缺口冲击强度提高200%,弯曲强度提高约4.5%,LDHs对体系力学性能的影响均呈先增大后减小的趋势。

The refractory properties of polyvinyl chloride(PVC) were modified by hydrotalcite(LDHs) and self-made copper-organic montmorillonite.The flame retardancy,thermal stability,rheological properties and mechanics of LDHs on PVC composites were investigated.The results showed that with the increase of LDHs content,the limiting oxygen index,heat resistance and smoke density of PVC composite system had a certain degree of influence,among which the limiting oxygen index was increased by 3.9% and the heat distortion temperature was increased by 3.8 ℃,the density dropped by about 6%.The thermal stability was improved and the residual carbon was increased,which could effectively reduce the production of HCl;The plasticizing torque and the balance torque were reduced,which was beneficial to the processing of the product;The proper content of LDHs could effectively improve the mechanical properties of the system,increase the tensile strength by20%,the notched impact strength by 200%,and the bending strength by about 4.5%.The influence of LDHs on the mechanical properties of the system increased first and then decreased.