PVC (Polyvinyl Chloride) Chemical and Physical Properti […]
PVC (Polyvinyl Chloride) Chemical and Physical Properties Rigid PVC is one of the most widely used plastic materials. PVC material is a non-crystalline material. PVC materials are often added with stabilizers, lubricants, auxiliary processing agents, colorants, impact agents and other additives in actual use.
PVC materials are non-flammable, high strength, weather resistant and excellent geometric stability. PVC is highly resistant to oxidizing agents, reducing agents and strong acids. However, it can be corroded by concentrated oxidizing acids such as concentrated sulfuric acid, concentrated nitric acid, and is also not suitable for contact with aromatic hydrocarbons or chlorinated hydrocarbons.
The melting temperature of PVC during processing is a very important process parameter. If this parameter is improper, it will lead to the problem of material decomposition. The flow characteristics of PVC are quite poor and the process range is narrow. In particular, large molecular weight PVC materials are more difficult to process (this material usually incorporates a lubricant to improve flow characteristics), so small molecular weight PVC materials are usually used. The shrinkage rate of PVC is quite low, generally 0.2 to 0.6%.
Injection molding process conditions
Drying treatment: Drying is usually not required.
Melting temperature: 185~205C Mold temperature: 20~50C
Injection pressure: up to 1500 bar Holding pressure: up to 1000 bar Injection speed: In order to avoid material degradation, a considerable injection speed is generally used.
Runners and gates: All regular gates can be used. If you are working with smaller parts, it is best to use tip-type gates or submerged gates; for thicker parts, it is best to use fan-shaped gates. The minimum diameter of the tip or submerged gate shall be 1 mm; the thickness of the fan gate shall not be less than 1 mm.
Typical uses Water supply pipes, household pipes, house wall panels, commercial machine casings, electronic product packaging, medical equipment, food packaging, etc.
