Name: polycarbonate.

Color: PC is a light yellow or colorless transparent material that is rigid and tough, with a high gloss.

Burning characteristics: flammable, slowly extinguished after leaving the flame, the upper end of the flame is golden yellow, and the lower end is blue. During combustion, black smoke and carbon beams are produced, and a strong "floral and fruity" odor is emitted.

Advantages: the biggest advantage of PC is its rigidity and toughness, mechanical strength is similar to nylon, size stability of PC is higher than nylon, its thermal stability is higher than polyoxymethylene, PC is transparent material, and the surface has a high gloss; PC is more resistant to impact than other materials.

Disadvantages: the biggest disadvantage of PC is that it has a high coefficient of wear, high wear, and no self-lubricating properties. Not resistant to stress cracking, it can dissolve and expand in steam and many organic solvents, leading to stress cracking; When making products with embedded components, special attention should be paid to the strength of the embedded parts, as PCs have a greater tendency to undergo high-temperature thermal deformation.

Purpose: to produce shells with high rigidity and high impact strength, including tool casings, electrical casings, and communication product casings. To produce transparent and heat-resistant casings and lenses with high rigidity and high impact strength. Production with high rigidity and high impact strength: internal components of electrical appliances, production with high rigidity and high impact strength: sports safety helmets.

Injection performance: PC is a crystalline plastic with a clear melting point. It melts at 220 ℃ and decomposes at 350 ℃. The general processing temperature is between 250 ℃ and 320 ℃; It absorbs water, and a small amount of water can cause it to decompose at high temperatures. When injection molding, it must be dried, and the drying temperature can be 120 ℃ for 4-5 hours.

The melting viscosity of PC material is high, and high pressure is required during injection molding.

When processing PC, if conditions permit, a mold temperature machine can be used to increase the mold temperature to reduce residual stress of the product. If it is a product with embedded parts and the diameter of the embedded parts is less than 1-2mm, preheating may not be considered. For larger embedded parts, preheating should be considered, otherwise stress cracking may occur.

The shrinkage rate of PC is independent of processing conditions and the wall thickness of the product. Its longitudinal and transverse shrinkage rates are relatively close, so it can be processed into high-precision products. Its shrinkage rate is 5 ‰, and the overflow value is 0.05mm.