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In the process of processing CPVC resin into finished or semi-finished products, \"plasticization\" is a crucial step. Whether it is extrusion molding or injection molding, the quality of plasticization has a direct impact on both the internal and surface quality of the product. Therefore, achieving good plasticization quality through appropriate processes, equipment, and techniques is the key to CPVC processing. The following points can help us understand how to improve the quality of plasticization during the CPVC processing process. First, the molecular formula of CPVC: CPVC (PVC-C) is a chlorinated product of PVC; it represents a chlorinated modification of polyvinyl chloride. This modified PVC can serve two purposes: one is to increase the heat distortion temperature, enhance rigidity, and improve chemical stability, as well as weather resistance and flame retardancy while reducing smoke density. Such products are typically used to manufacture items for applications with special requirements ； The second is to improve the solubility of the material. This product is commonly known as vinyl chloride, and it is mainly used in the production of adhesives, coatings, and chlorinated synthetic fibers. The chlorination method for CPVC is aqueous suspension (slurry) chlorination. Its molecular structure is -CHCl-CHCl-CH2-CHCl-. The properties of CPVC are determined by two factors: the chlorine content and the distribution of chlorine along the CPVC molecular chain. Therefore, CPVC with the same chlorine content can exhibit significant differences in performance due to variations in the distribution of chlorine atoms. II. Relevant factors for improving the plasticization quality during the molding process. This article discusses the extrusion molding of CPVC. Since the melt viscosity of CPVC is at least twice that of PVC, the processing temperature is high; this leads to difficulties in shaping during processing as well as corrosion of the equipment due to the release of HCl resulting from thermal decomposition. During the extrusion process, determining how to achieve ideal \"plasticization\" of CPVC, a material with high viscosity, is the key to CPVC processing technology. Therefore, it has special requirements for the formulation – specifically, regarding heat stabilizers. Due to the high processing temperatures of CPVC, the amount of heat stabilizer required in the formulation is much higher than that for PVC. Clearly, traditional trisalt and disalt heat stabilizers are not suitable for use in this context. The currently more mature heat stabilizers are composite lead-series stabilizers with a lubrication system. The requirements for lubricants: Due to the very high melt viscosity of CPVC, melt breakdown easily occurs during injection molding; therefore, using only conventional lubricant systems based on paraffin, stearic acid, and metal soaps is not suitable. In the extrusion processing of CPVC, since CPVC has a tendency to adhere to the metal surfaces of post-extrusion equipment (especially the die head and molds), external lubricants must be added to the formula in order to eliminate this adhesion. The external lubricant should be immiscible with the CPVC resin. In CPVC molding (especially injection molding), under pressure, the friction between CPVC resins generates heat. The formation of this frictional heat is detrimental to the molding process and must be controlled. Internal lubricants can reduce the friction between resins during CPVC processing. The internal lubricant should be soluble in CPVC resin. It should be noted that the balance between internal and external lubrication in the formula is key. Excessive internal lubrication can severely affect \"plasticization\", leading to a decline in the quality of the product ； Excessive external lubrication can cause the lubricant to separate, and may even lead to problems such as screw slippage, which severely affect normal production. OP wax (lignite ester wax) in saponified waxes is an ideal internal and external composite lubricant.