Why Are Polyvinyl Chloride (PVC) Commonly Used For Pre-insulated Bushings?

In electrical engineering wiring systems, the choice of materials directly affects the long-term performance of equipment. As a core component of wire and cable protection, the material composition of pre insulated sleeve needs to meet multiple technical indicators. Polyvinyl chloride (PVC) has gained widespread acceptance in this field, a phenomenon underpinned by profound materials science principles.

From a molecular structure perspective, PVC is a polymer compound formed by the polymerization of vinyl chloride monomers. The chemical bond structure of this material endows it with stable physicochemical properties. In acidic or alkaline environments, pre insulated junction sleeve needs to resist chemical corrosion, and the molecular chain structure of polyvinyl chloride can remain stable under such conditions. Temperature adaptability is another consideration; the material can maintain performance within a temperature range of -15℃ to 60℃, covering most building wiring scenarios.

In terms of electrical performance, PVC has a volume resistivity exceeding 10¹² Ω·cm, meeting the insulation requirements of low-voltage power distribution systems. The insulated joint sleeve series circuit serves to isolate the conductor from the external environment, and the dielectric strength of the material determines whether it can operate for a long time under the rated voltage. Flame retardant properties are also important. Polyvinyl chloride contains chlorine, and the hydrogen chloride released during combustion has an inhibitory effect on combustion, making the oxygen index of the material reach more than 40, which meets the basic requirements of building electrical codes for fireproof materials.