Some Knowledge Points About ABS Materials
ABS is a polymer formed by the copolymerization of three monomers of acrylonitrile (23-41%), butadiene (10-30%), and styrene (29-60%). The English name is Acrylonitrile-Butadiene-Styrene, referred to as ABS. ABS has the unique advantages of toughness, rigidity, and hardness. It develops rapidly and is widely used.
Characteristics of ABS
1. ABS is an amorphous, opaque resin, generally light yellow pellets or beads. It has good comprehensive properties and is a tough, hard, and rigid thermoplastic engineering plastic. Acrylonitrile endows ABS with chemical corrosion resistance, oil resistance, and certain rigidity and hardness;
2. Butadiene improves the toughness, impact resistance, and cold resistance of ABS;
3. Styrene makes ABS have good dielectric properties and gloss, and sound processing fluidity.
In addition, ABS is easy to process and shape. The melting temperature is 217~237°C, and the thermal decomposition temperature is more excellent than 250°C. The molding shrinkage rate is small, and the product has good dimensional stability.
4. ABS is non-toxic, tasteless, and has low water absorption. It is easy to carry out surface decoration such as painting, dyeing, and electroplating.
5. The disadvantage of ABS is that due to the double bond produced by butadiene, the weather resistance is poor, and it is easy to age, change color, or even crack after long-term outdoor exposure, thereby reducing the impact strength and toughness. ABS is easily soluble in aldehydes, ketones, esters, and chlorinated hydrocarbons, is flammable, and has a low heat distortion temperature.
6. ABS burns slowly and continues to burn after leaving the fire. The flame is yellow and black smoke is emitted. It softens and burns after burning, has a unique smell, and has no molten material dripping.
7. ABS is an amorphous polymer, and like polystyrene, it has excellent processing properties and can undergo various processes including injection, extrusion, calendaring, and thermoforming. It can also undergo secondary processes such as machining, welding, bonding, painting, and electroplating. In terms of secondary processing, ABS has a surface that is highly receptive to metal electroplating, resulting in a coating-to-ABS adhesion that is 10 to 100 times stronger than other plastics. This not only enhances the aesthetics but also improves the weather resistance of ABS.
8. In addition, welding can utilize flame-retardant ABS electrodes. You can bond it using a 10% ABS solution of methyl ethyl ketone. Shape the pipe by applying hot oil or hot air. Vacuum forming is possible with extruded or calendered sheets. Manufacturers have developed various cold-formed ABSs in recent years. They enable cold-stamping to produce products similar to steel and aluminum, making them particularly suitable for manufacturing large automotive parts.
Material properties of ABS
1. Conventional performance:
Plastic ABS is non-toxic and tasteless; its appearance is ivory translucent or transparent granules or powder. The density is 1.05~1.18g/㎝3, the shrinkage rate is 0.4%~0.9%, the elastic modulus is 2Gpa, the Poisson’s ratio is 0.394, the hygroscopicity is <1%, the melting temperature is 217~237℃, and the thermal decomposition temperature is >250 ℃.
2. Mechanical properties:
Plastic ABS exhibits excellent mechanical properties, with outstanding impact strength and the ability to withstand extremely low temperatures. It also demonstrates exceptional wear resistance, good dimensional stability, and resistance to oil. As a result, it is suitable for applications involving medium loads and low-speed bearings. The creep resistance of ABS is larger than that of PSF and PC, but smaller than that of PA and POM.
3. Thermal properties:
Plastic ABS has a thermal deformation temperature ranging from 93°C to 118°C, and annealing can increase the product’s temperature resistance by approximately 10°C. ABS exhibits a certain level of toughness even at -40°C, allowing it to be utilized within a temperature range of -40°C to 100°C.
4. Electrical properties:
Plastic ABS has good electrical insulation and is hardly affected by temperature, humidity, and frequency, so it can be used in most environments.
5. Environmental performance:
Plastic ABS is not affected by water, inorganic salts, alkalis, and various acids, but it is soluble in ketones, aldehydes, and chlorinated hydrocarbons. It will cause stress cracking when it is eroded by glacial acetic acid and vegetable oil. The weather resistance of ABS is poor, and it is easy to degrade under the action of ultraviolet light; after half a year outdoors, the impact strength drops by half.
ABS injection mold process conditions:
Drying treatment: ABS material is hygroscopic and requires drying treatment before processing. The recommended drying condition is at least 2 hours at 80-90°C. Material humidity should be guaranteed to be less than 0.1%.
Melting temperature: 210～280℃; recommended temperature: 245℃.
Mold temperature: 25～70℃. (Mold temperature will affect the finish of plastic parts, a lower temperature will result in a lower finish).
Injection pressure: 500~1000 bar.
Injection speed: medium to high speed.
Application of ABS materials
Electrical field:
The casing and internal components of refrigerators, televisions, washing machines, air conditioners, telephones, air conditioners, and other electrical appliances.
Automotive field:
Automotive dashboards, body panels, interior trim panels, steering wheels, sound insulation panels, door locks, bumpers, ventilation ducts, and many other components. ABS is mainly used for impact resistance, such as strength, stiffness, and formability. Accessories include fenders, armrests, vent covers, supports, cushion extensions, and more.
Building materials field:
ABS pipes, ABS sanitary ware, ABS decorative boards. In addition, ABS is also widely used in packaging, furniture sporting goods and entertainment products, machinery, and instruments in industry.
Office equipment:
Taking advantage of the excellent impact resistance, excellent rigidity, dimensional stability, and formability of ABS board, it is economical and practical to manufacture various office equipment shells. Office equipment such as fax machines, copiers, typewriters and computer monitors, keyboards, etc. have higher requirements for fire protection, so generally, flame-retardant ABS is used in the preferred order.
Mechanical field:
ABS plastic casing can be used in the production of mechanical equipment and general mechanical parts, such as water tanks, exterior shells, electrical cabinets, battery tanks, gear bearings, pump impeller mold models and fasteners, bolts, and cover plates.
Mold model:
Due to its superior processing performance, light specific gravity, and low price, ABS plastic has been widely used to manufacture mold models for household appliances, automobiles, mechanical equipment, and testing instruments in recent years. Currently, the world’s leading three-dimensional prototype is made of ABS as standard material, then you can make any appearance, suitability, and related function models of any new product you want to test. It has the best performance-price ratio among similar products.
Others:
ABS can be used to make structural foam plastics, flame-retardant plastics, and reinforced plastics. Blended with PVC, PUR, PC, PSU, etc. to make a polymer alloy with excellent performance.
How to improve the heat resistance of ABS plastic?
1. Let the molecular model of the polymer form a three-dimensional structure and form a mesh, thereby inhibiting molecular movement;
2. Add aromatic and alicyclic structures that are difficult to move into the molecular structure;
3. Add polar groups to the polymer, thereby relying on the binding force of the hydrogen-oxygen chain to inhibit the molecular structure;
4. Introduce the crystal structure into the polymer structure for heat-resistant modification, using heat-resistant modifiers.
ABS modified series include heat-resistant grade, electroplating grade, high-gloss grade, flame-retardant grade, etc., with complete categories and excellent performance, widely used in home appliances, auto parts, building materials, etc.
DOME Materials can provide custom modified ABS keyboard materials (70%-80% transparent new/recycled ABS raw materials + 30%-20% PMMA + 4% Laser Marking Additives)
The black keyboard is marked white, and the laser marking effect is as follows:
