The plastic contains ABS acrylonitrile-butadiene-styrene copolymer, PA12 polyamide 12 or important components.

Introduction

Typical application range:

Automobiles (instrument panels, tool hatches, wheel covers, mirror boxes, etc.), refrigerators, high-strength tools (hair dryers, blenders, food processors, lawn mowers, etc.), telephone housings, typewriter keyboards, recreational vehicles such as golf carts and jet snowmobiles, etc.

Injection molding process conditions:

Drying treatment: ABS material is hygroscopic and requires drying before processing. The recommended drying conditions

are at least 2 hours at 80~90C. The material temperature should be guaranteed to be less than 0.1%.

Melting temperature: 210~280C; recommended temperature: 245C.

Mold temperature: 25бн70C. (Mold temperature will affect the finish of the plastic part, and lower temperature will result in lower finish).

Injection pressure: 500~1000bar.

Injection speed: medium to high speed.

Chemical and physical properties:

ABS is synthesized from three chemical monomers: acrylonitrile, butadiene and styrene. Each monomer has different properties: acrylonitrile has high strength, thermal stability and chemical stability; butadiene has toughness and impact resistance; styrene has easy processing, high finish and high strength. From a morphological point of view, ABS is a non-crystalline material.

The polymerization of the three monomers produces a terpolymer with two phases, one is a continuous phase of styrene-acrylonitrile, and the other is a dispersed phase of polybutadiene rubber. The characteristics of ABS mainly depend on the ratio of the three monomers and the molecular structure in the two phases. This allows great flexibility in product design, and has resulted in hundreds of different qualities of ABS materials on the market. These different qualities of materials provide different properties, such as medium to high impact resistance, low to high finish and high temperature distortion characteristics.

ABS material has excellent ease of processing, appearance characteristics, low creep and excellent dimensional stability and high impact strength.

Material

Typical application range:

Water meters and other commercial equipment, cable sets, mechanical cams, sliding mechanisms and bearings, etc.

Injection molding process conditions:

Drying treatment: The humidity should be kept below 0.1% before processing. If the material is stored in the air, it is recommended to dry it in 85C hot air for 4~5 hours. If the material is stored in a closed container, it can be used directly after 3 hours of temperature equilibrium.

Melting temperature: 240~300C; do not exceed 310C for ordinary characteristic materials, and do not exceed 270C for flame retardant materials.

Mold temperature: 30~40C for unreinforced materials, 80~90C for thin-walled or large-area components, and 90~100C for reinforced materials. Increasing the temperature will increase the crystallinity of the material. Accurate control of mold temperature is very important for PA12.

Injection pressure: Up to 1000bar (low holding pressure and high melting temperature are recommended).

Injection speed: High speed (better for materials with glass additives).

Runners and gates:

For materials without additives, the runner diameter should be around 30mm due to the low viscosity of the material. For reinforced materials, a large runner diameter of 5~8mm is required. The runner shape should be all circular. The injection port should be as short as possible. Various forms of gates can be used. Do not use small gates for large plastic parts to avoid excessive pressure or excessive shrinkage on the plastic parts. The gate thickness should be equal to the thickness of the plastic part. If a submerged gate is used, the recommended minimum diameter is 0.8 mm.

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