Polyvinyl chloride (PVC) film has been widely used in decorative materials, building materials and other fields because of its excellent comprehensive performance and cost effectiveness. However, the heat resistance of PVC film has been the focus of attention in the industry.
1. Softening and melting temperature: PVC film has no fixed melting point, usually begins to soften at 80 ~ 85 ° C, 130 ° C becomes viscoelastic, 160 ~ 180 ° C begins to change into viscoelastic state.
2. Thermal stability: The thermal stability of PVC is poor, its melting temperature is about 200℃, and it begins to decompose and release hydrogen chloride at 100℃, and the decomposition is accelerated when it is higher than 150℃. Therefore, the Vica softening point of general PVC resin is only about 80 ° C, and the thermal deformation temperature is about 70 ° C.
3. Heat resistance modification: Through modification, the heat resistance of PVC can be improved. For example, the heat resistance of crosslinked PVC is higher than that of ordinary PVC, and the radiation crosslinked wire can be used continuously at 100~110 ° C. In addition, PVC blending with other polymers can also improve the heat resistance.
4. Application of heat-resistant PVC: Heat-resistant PVC film can be used for applications requiring a higher temperature environment, such as the surface of decorative materials or building materials.
5. Thermal conductivity: The thermal conductivity or thermal conductivity of unmodified ordinary PVC is very low, generally 0.2-0.46W/(m·K) or so. Through thermal conductivity modification, the thermal conductivity or thermal conductivity of thermal conductive plastics can be greatly improved.
6. Heat resistance improvement method: The heat resistance of PVC can be improved by adding heat resistance modifiers, adding inorganic fillers, adding glass fibers, etc. For example, by adding 20% to 30% glass fiber, the heat resistance of PVC can be increased to more than 100 ° C.
PVC film itself has limited heat resistance, but its heat resistance can be significantly improved by modification and addition of various additives to meet higher temperature requirements.