Chlorinated polyethylene (CPE)

Chlorinated polyethylene (CPE), as a traditional and widely used toughening agent for PVC, holds an important position in the field of PVC processing due to its unique performance characteristics.

1. Structural characteristics of CPE
CPE is a polymer material obtained by the chlorination reaction of high - density polyethylene (HDPE). The chlorine content is a key factor affecting the properties of CPE, and generally, the chlorine content is between 30% - 40%.

2. Toughening mechanism for PVC
CPE has rubber - like elasticity. When added to PVC, it forms a dispersed phase in the PVC matrix. When subjected to external impact, the rubber - phase region of CPE can undergo elastic deformation and absorb a large amount of energy. At the same time, the rubber - phase particles can act as stress - concentration points, triggering the formation of crazes and shear bands in the surrounding PVC matrix. The development and interaction of crazes and shear bands consume energy, preventing the rapid propagation of cracks and thus improving the toughness of PVC. Compatibility and interfacial action: CPE has a certain degree of compatibility with PVC, enabling the formation of a good interfacial bond between the two. This interfacial bonding force helps to effectively transfer stress between the CPE rubber phase and the PVC matrix, giving full play to the toughening effect. Appropriate interfacial action not only ensures the uniform dispersion of CPE in PVC but also enables the two to jointly resist external forces and improve the overall performance of the material.

3. Application scenarios in PVC products
Door and window profiles: This is one of the most widely used fields for CPE - toughened PVC. The toughening effect of CPE makes the profiles less likely to break when subjected to external impact, improving the safety and durability of doors and windows. It also maintains the stability of color and performance, and is less prone to problems such as aging and fading.
Pipe fittings: In the production of PVC pipe fittings, CPE is often used to produce drainage pipes, wire and cable sheaths, etc. For drainage pipes, the pipes need to have a certain degree of toughness to adapt to different installation environments and resist possible external impacts. In wire and cable sheaths, CPE not only provides a toughening effect but also enhances the flame - retardant properties of the pipes, ensuring the safe use of wire and cable.
Stone - plastic boards: Stone - plastic boards are commonly used in fields such as building decoration and advertising production. They have high requirements for hardness and rigidity, but at the same time, they also need to have a certain degree of toughness to prevent brittle fracture. After adding an appropriate amount of CPE toughening agent, the impact strength of stone - plastic boards is significantly improved.