What are the ways to improve the heat resistance of PVC plastics?
1. PVC copolymer
PVC(vinyl chloride) and other monomer copolymer resin composition if there are polar or large groups of components, the copolymer thermal deformation temperature increases accordingly, heat resistance is better than PVC, heat resistant products were made. PVC softening temperature is 78 ℃, and vinyl chloride vinylidene chloride and vinyl chloride copolymer of methyl methacrylate, vinyl chloride softening temperature of a propylene eyes were 100 ~ 130, 85, 140 ~ 150 ℃.
2. Chlorination of PVC
Chlorinated polyvinyl chloride is made from PVC resin chlorinated, its chlorine content is 62%~68%. Chlorinated polyvinyl chloride (PVC) can be used continuously under 100 ℃ (higher than PVC 20 ~ 35 ℃), the highest temperature can reach 100 ~ 105 ℃. And the chemical stability, fire resistance, cold resistance are better than PVC. But the chlorination equipment antisepsis request is stricter. Resin is not easy to process and its application and development are restricted by its poor impact toughness.
3. PVC cross-linking
Crosslinked PVC can be prepared by radiation crosslinking and chemical crosslinking. The crosslinked PVC products have higher mechanical strength, better dimensional stability, heat resistance, deformation, wear resistance and chemical resistance than ordinary PVC products. Radiation crosslinking wire can be continuous use under 100 ~ 110 ℃.
4. PVC is blended with other polymers
PVC is mixed with other polymers in a certain proportion, and the performance (full compatibility) of the blend is improved compared with PVC. Because of the compatibility of the two kinds of polymer mixing, can reach the molecular level of mutual melting, forming a single phase structure, so that the properties of the blend can be supplemented and strengthened, such as PVC/PS, PVC/PE, PVC/CPVC.
5. Add heat-resistant modifier
Heat resistant modifier is a kind of polymer with high heat resistance developed and produced in order to improve the heat resistance of PVC.
6. Add inorganic filler to PVC
Adding a certain amount of filler, can improve the heat resistance of PVC. Commonly used fillers are: heavy calcium carbonate, light calcium carbonate, precipitated calcium carbonate, calcined pottery, barium sulfate, red mud, titanium powder and so on.
7. Add glass fiber into PVC
Adding 20% ~ 30% glass fiber, PVC in without (or less) under the condition of plasticizer, its heat resistance can be increased to more than 100 ℃. Especially long fiber reinforced PVC, its thermal deformation temperature increased more significantly.