Brilliant Polycarbonate LED Light Diffusers

Polycarbonate LED Light Diffusers specification

Material : Polycarbonate 2805

Color : Clear

Height : 20mm

Width : 500mm

Thickness : 1mm

Weight : 210g/meter

What is the injection temperature of flame-retardant PC plastic? Can it be injection molded?

Specific gravity of flame retardant PC: 1.18-1.20 g / cubic centimeter molding shrinkage: 0.5-0.8% molding temperature: 230-320 ℃ drying conditions: 110-120 ℃ for 8 hours, it can be used for a long time under -60~120 ℃. The material has high impact strength, good dimensional stability, colorless and transparent, good coloring, good electrical insulation, corrosion resistance and wear resistance, but it has poor self lubrication, stress cracking tendency, easy hydrolysis at high temperature, and poor compatibility with other resins. Suitable for making small instrument parts, insulating transparent parts and impact resistant parts.

Performance of PC plastic raw materials at injection temperature:

1. Amorphous material, good thermal stability, wide molding temperature range and poor fluidity. Moisture absorption is small, but it is sensitive to water and must be dried. The molding shrinkage is small, which is prone to melting cracking and stress concentration. Therefore, the molding conditions should be strictly controlled, and the plastic parts must be annealed.

2. Heated extension nozzle should be used for plastic parts with high melting temperature and high viscosity, which are greater than 200g.

3. The cooling speed is fast, and the mold pouring system is based on the principle of thick and short. It is appropriate to set a cold charging well, the gate should be larger, and the mold should be heated.

4. If the material temperature is too low, it will cause material shortage, plastic parts are Matt, and if the material temperature is too high, it is easy to overflow and plastic parts blister. When the mold temperature is low, the shrinkage, elongation and impact strength are high, and the bending, compression and tensile strength are low. When the mold temperature exceeds 120 ℃, the plastic part cools slowly and is easy to deform and stick to the mold

1、 Process characteristics I

1. The fluidity of the solution is sensitive to temperature and insensitive to pressure. It is close to Newtonian fluid and belongs to viscosity temperature sensitive type.

2. It can be regarded as an amorphous polymer, with no obvious melting point, high melt viscosity and difficult flow. It is required that the mold runner gate is short and thick to reduce pressure loss, and at the same time, higher injection pressure is required.

3. Under high temperature, the resin is easy to hydrolyze, and silver wires are produced on the products. The resin should be dried before processing, so that the water content is below 0.02%. During the processing process, attention should be paid to the insulation of the resin to prevent the resin from absorbing moisture again.

4. The products are easy to crack, so pay attention to eliminate the internal stress of the products during processing, such as increasing the mold temperature and post-treatment of the products.

Process characteristics II

1. The molding shrinkage of the product is 0.5-0.7%, and the flow direction is basically consistent with the vertical direction.

The fluidity of the solution is related to the wall thickness of the product. The flow length ratio of PC solution is 80-100:1, and the thickness of the product is generally not less than 1mm, mostly between 1.5-5mm;

2. For products with wall thickness less than 3mm and flow length less than 250mm, it is allowed to adopt point gate diameter of 0.8-1mm;

3. The depth of exhaust slot is less than 0.03mm;

4. In order to help smooth mold filling, the mold temperature can be selected between 120-0 ℃;

2、 Requirements for forming equipment

1. Equipment capacity: it is required that the injection volume of products shall not exceed 60-70% of the nominal volume of the injection molding machine

2. Screw: the length diameter ratio l/d of the screw is 15-20, and the compression ratio is 2-3.

3. Temperature control instrument: the temperature control instrument is required to be freely adjusted between 400 ℃ -0 ℃.

4. Nozzle: due to the poor fluidity of PC, the nozzle hole diameter is 3-6mm, the hole length is 12-25mm, and is equipped with a separate heating device.

Led Light Diffuser picture: