Polyvinyl chloride (PVC): the density is about rho = 1.4, when burning with flame there is black smoke, remove the flame automatically extinguished. According to its performance, it can be divided into ordinary PVC, PVC that meets UL requirements, and SR-PVC. Ordinary PVC has poor tensile strength and elongation properties, and its temperature rating is relatively low. PVC which meets the requirements of UL has good tensile strength and elongation, and its use can be divided into PVC of different materials, which is not easy to burn.

SR-PVC: SR-PVC is semi-rigid PVC, fire-resistant, high strength, temperature and voltage resistance are better than PVC, not easy to burn, burning acid pungent place and sinking in water.
Polypropylene (PP):The density is about =0.9, which is commonly used in low voltage cables. It has good tensile resistance, excellent elongation, light weight, easy to burn, while burning, gas and oil droplets have the smell of combustion.
Polyethylene (PE):The density is between 0.91-1.26. It is easy to burn. When burning, the edges of the edges burn with the smell of paraffin burning. It is often used in signal cables. Commonly used PE has LD-PE, HD-PE and FM-PE.
Low density PE (LD-PE):The density is =0.91-0.92, light and easy to burn.
High density PE (HD-PE):The density is =0.94-0.95, light and easy to burn. Harder than LD-PE.
Foamed PE (FM-PE):The material is soft and combustible. Under microscope, the porosity is poor, and its insulation is poor.