ABS is synthesized from three chemical monomers of acrylonitrile, butadiene and styrene. Each monomer has different characteristics: acrylonitrile has high strength, thermal stability and chemical stability; butadiene has toughness and impact resistance; styrene has easy processing, high finish and high strength.
Process conditions for injection molding of acrylonitrile-butadiene-styrene copolymer
Drying treatment: ABS material is hygroscopic and requires drying treatment before processing. It is recommended that the drying conditions be at least 80 hours at 80 ~ 90 ℃. The material temperature should be guaranteed to be less than 0.1%.
Melting temperature: 210 ～ 280 ℃; recommended temperature: 245 ℃.
Mold temperature: 25 ～ 70 ℃. (The mold temperature will affect the finish of the plastic parts, and the lower temperature will result in a lower finish).
Injection pressure: 500 ～ 1000bar.
Injection speed: medium to high speed.
HDPE high density polyethylene injection molding process conditions
Drying: No drying is necessary if stored properly.
Melting temperature: 220 ~ 260 ℃. For materials with larger molecules, it is recommended that the melting temperature range be between 200 and 250 ° C.
Mold temperature: 50 ~ 95 ℃. Plastic parts with wall thickness below 6mm should use higher mold temperature, and plastic parts with wall thickness above 6mm should use lower mold temperature. The cooling temperature of the plastic parts should be uniform to reduce the difference in shrinkage. For the optimal processing cycle time, the diameter of the cooling cavity should not be less than 8mm, and the distance from the mold surface should be within 1.3d (here “d” is the diameter of the cooling cavity).
Injection pressure: 700 ~ 1050bar.
Injection speed: High-speed injection is recommended.
Runner and gate: The runner diameter is between 4 and 7.5mm, and the runner length should be as short as possible. Various types of gates can be used, the gate length should not exceed 0.75mm. Especially suitable for the use of hot runner molds.