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1. PVC - Polyvinyl chloride (PVC) plastic is a multi-component mixture based on polyvinyl chloride resin. According to the requirements of various automobile wire harnesses, plasticizers, stabilizers, fillers, flame retardants, processing aids (lubricants), ultraviolet absorbers, colorants and special purpose additives are added into the PVC formula, which is mainly used for insulation and sheath (mainly at 70, 80, 90 and 105 degrees). Basic judgment method: when burning, yellow flame, black smoke, green flame at the bottom and foul smell.

2. PE - polyethylene has excellent electrical insulation (dielectric constant and dielectric loss tangent tg δ It has good chemical stability, low permeability and water absorption, small specific gravity, non-toxic, good plasticity, and is easy to process. It is mainly used for communication cable insulation, car harness, etc. Basic judgment method: compare and record the light on the surface. When burning, the flame will be yellow and blue, drip and have a slight candle smell.

3. PP - Polypropylene is white waxy solid in appearance, transparent, non-toxic, low water absorption, only 0.03-0.04%, flammable. The specific gravity is 0.91, which is the smallest plastic in common use at present. It is mainly used for core wire insulation, such as automobile wire harness. Basic judgment method: the surface is relatively smooth and hard compared with PE. When burning, the flame is yellow and blue, dripping and smelly, and then there is a slight candle smell.

4. XLPE/XL-PVC - thermosetting material, mainly used for insulation. The maximum temperature resistance grade of XLPE can reach 150 ℃. Basic identification method: cut a section of wire, remove the conductor, burn it from the middle with fire, and then break the wire with force. The section is very round.

5. PU - With good physical and chemical properties, it is often used for the sheath of connecting wire and spring wire of construction machinery and other equipment. Basic identification method: magnetic, good elasticity, swelling and dripping when burning.

6. TPE/PO (thermoplastic elastomer) - low smoke halogen-free fuel.

Of course, the insulating material of automobile wire harness is also used in many aspects, such as wires and cables.