PVC formulation is the most complex of all plastics, and the complexity of PVC formulations is the application of lubricants. If you understand the classification and application principles of lubricants, PVC formulations can be mastered.
PVC lubricants can be divided into two types. The external lubricant mainly has poor compatibility with polymers and easily migrates out from the melt, so it can form a thin layer of lubrication at the interface between the plastic melt and the metal. . The internal lubricant has good compatibility with the polymer, and it acts to reduce the cohesive force between the polymer molecules inside the polymer, thereby improving the internal friction heat generation and melt flowability of the plastic melt. Of course, most lubricants have the dual effect of internal and external lubricants, rather than a simple one, such as stearic acid, the external lubrication characteristics predominate in the case of low initial temperature or high dosage, and the temperature rises with pvc When the compatibility is increased, the internal lubrication is mainly used.