1) liquidity

润滑剂对PVC的熔融和流动性有显著影响。充分扩散的外润滑剂覆盖在树脂粒子表面，使摩擦热减少，以物理作用推迟粒子的聚结和熔化，阻碍大分子链短链段的相互扩散。充分分散的内润滑剂起假增塑的作用，促进聚合物熔化。合理的润滑体系是调控PVC塑化速率的最有效、最常用的方法。外润滑剂通过减少对金属表面的点附性及摩擦力，延长塑化时间。内润滑剂在高温下削弱了PVC分子间的内聚力，促进熔化，增加流动性。

The lubricant has a significant effect on the melting and fluidity of PVC. The full diffusion of the external lubricant is covered with the surface of the resin particles, which reduces the friction heat, and delays the coalescence and melting of the particles by physical action, and hinders the mutual diffusion of the short chain segments of the large molecular chain. Fully dispersed internal lubricants play a role of pseudo plasticization and promote polymer melting. A reasonable lubrication system is the most effective and commonly used method to control the plasticization rate of PVC. External lubricants extend the plasticizing time by decreasing the point attachment and friction force on the metal surface. The internal lubricant weakens the cohesive force between PVC molecules at high temperature, promotes melting and increases fluidity.

2) 热稳定性

2) thermal stability

润滑剂能降低加工时的料温，促进物料稳定，如金属皂润滑剂本身就是热稳剂；甘油单酯是热稳定剂的螯合剂；另一些润滑剂与稳定剂产生协同效应。

The lubricant can reduce the temperature of the processing and promote the stability of the material, such as the metal soap lubricant itself is the thermal stabilizer; the glycerol monoester is the chelating agent for the heat stabilizer; the other lubricants have synergistic effect with the stabilizer.

3) 干混料的物性

3) physical properties of dry mixture

润滑剂能影响PVC高速混合时的压实程度及最终的表观密度和凝胶化程度，用双螺杆挤出时尤其如此，挤出量与干混料的表观密度成正比，同时部分凝胶化的粒料在熔融挤出中所需的能量较少，因而挤出量高。

The lubricant can affect the degree of compaction and the final apparent density and the degree of gelation of PVC at high speed. In particular, the extrusion quantity is proportional to the apparent density of the dry mixture when the twin screw extruders are extruded. At the same time, the energy required for the partially gelatinization of the granular material is less, and the extrusion amount is high.