The performance characteristics of ABS
As A result of the composition characteristics of ABS, it not only has the characteristics of A, B and S component homopolymer respectively, but also highlights the synergistic effect between the three components, making it present A relatively ideal and comprehensive comprehensive performance.Among them, styrene provides rigidity, workability and dyeing properties, butadiene provides toughness, enhances impact strength, acrylonitrile enhances chemical resistance, and increases heat deformation temperature, surface hardness and tensile strength.Usually ABS has better heat resistance than high impact polystyrene.Vicat softening point usually at about 95 ℃ (high heat resistance level of up to 110 ℃), usually in the heat deformation temperature of 90 ℃ or so grade (high heat resistant up to 100 ℃).Due to the existence of rubber components, ABS has good cold resistance.In 40 ℃ - still showed good toughness.Because of its heat and cold, the use of wide temperature range, can generally be from - 40 ℃ ~ 100 ℃.The linear expansion coefficient of ABS is small, the product has good dimensional stability and good creep resistance.When subjected to 7Mpa load, the size did not change significantly, and the creep resistance did not drop rapidly when the temperature was rising.ABS has good comprehensive mechanical properties.Tensile strength, bending strength, impact strength and hardness are all high.Individual performance values can vary greatly from brand to brand.The impact strength of ABS cantilever beam is generally 100 ~ 400J/m.Tensile strength is generally 35 ~ 55MPa, bending strength is 55 ~ 85Mpa, rockwell hardness is R90 ~ 115.ABS has been widely used as engineering materials because of its good mechanical properties and good creep resistance.ABS is capable of resisting water, inorganic acid, alkali and salt, but it is not resistant to oxidizing acid, glacial acetic acid, mineral oil, vegetable oil, alcohols, which will have a great impact on the internal stress of the components, and long-term contact may even cause environmental stress cracking.Ketones, aldehydes, esters, halogenated hydrocarbons and aromatics may cause swelling or dissolution.In addition, due to the existence of group B (butadiene) in ABS, the structure contains double bonds, poor weather resistance, easy to generate photooxidation aging and thermal oxygen aging.In order to improve the weather resistance, antioxidant and light stabilizer can be added.ABS has excellent forming and processing properties.General molding processing temperature at 180 ~ 230 ℃.Its liquidity than polystyrene is a bit poor, thermal stability is not as good as polystyrene and polyethylene, high processing temperatures generally do not exceed 250 ℃.Water has a great influence on the appearance of ABS molded products.Although the water absorption rate of ABS is not high (generally around 0.3%), a small amount of water will cause the appearance of silver silks on the product surface.Therefore, it is different from processing PE, PP and PE.The raw materials must be dried and the moisture content should be kept below 0.6%.ABS has a low shrinkage rate (generally 0.4-0.6 %) and a small deformation after products.Therefore, it is easy to shape parts with high dimensional precision.In addition, ABS is easy to be colored and has excellent secondary processing characteristics, such as easy surface decoration such as electroplating, good thermal forming, etc.