PE蜡和硬脂酸钙对PVC的树脂润滑作用——OPE蜡的影响与机理

通过转矩流变仪测定塑化时间(tf),并比较塑化时间延长效应Δtf=tf(PVC+润滑剂)-tf(PVC)],研究了高密度氧化聚乙烯蜡A-C 316A对聚乙烯蜡A-C 617A和硬脂酸钙(CaSt2)作为PVC润滑剂润滑性能的影响。结果表明,A-C 617A单独使用及其与CaSt2并用时,PVC树脂的外润滑性能均由于A-C 316A的添加而下降,而A-C 617A-CaSt2并用体系的性能下降,这是A-C 617A性能下降和协同效应没有叠加的结果,因此,其幅度比A-C 617A单独使用时更大。由此可以推测,A-C 316A的效应并不能归因于内润滑作用,其实际机理应该是由于独特的结构、性质,其既难溶于PVC又难溶于A-C 617A,但是却可以吸附A-C 617A和吸收CaSt2,而吸附A-C 617A则可以导致其有效用量减少,吸收CaSt2,破坏了A-C 617A-CaSt2的协同作用。

Resin Lubrication of Polyethylene Waw and Calcium Stearate on PVC——Effect of Oxidized Polyethylene Wax and Mechanism

The effects of A-C 316A,a high-density oxidized polyethylene wax,on the resin lubrication performances of A-C 617A,a polyethylene wax,and calcium stearate(CaSt2)as PVC lubricants were investigated by determining the fusion times(tf)using a torque rheometer and comparing the fusion time increasesΔtf=tf(PVC+lubricant)-tf(PVC)].It was shown that the resin external lubrication performances of A-C 617A and its combination systems with CaSt2 were all decreased by addition of A-C 316A,but the performance decreased of A-C 617A-CaSt2 combination systems were greater than A-C 617A used alone,because the performance decreases of the combination systems were the result of the loss of their synergistic effect and the performance decrease of A-C 617A.It could be speculated that the effects of A-C 316A could not be attributed to the internal lubrication,and the actual mechanism might be as follows,due to the unique structure and properties,it was difficult to dissolve in PVC and insoluble in A-C 617A,but it could adsorb A-C 617A and absorb CaSt2,and the effective dosage of A-C 617A would be cut down when it was adsorbed,the synergistic effect of A-C 617A and CaSt2 would be destroyed when CaSt2 was absorbed.