First, ASA and ABS material structure
1) ASAASA (acrylonitrile-styrene-acrylate terpolymer) engineering plastics is a graft copolymer of acrylic rubber and acrylonitrile, styrene.
2) ABS plastic, a polymer material of acrylonitrile A, butadiene B and styrene S,
Second, the contrast between ABS and ASA
1.ABS advantages and disadvantages
advantage:
ABS has excellent overall performance, excellent impact strength, good and low temperature performance, and little drop in strength at low temperatures.
Abrasion resistance: ABS has good wear resistance, although it can not be made of self-lubricating material, but due to good dimensional stability, it can be used for medium-load bearings.
Creep resistance: varies depending on the type. Ultra-high-break ABS products can withstand 7Mpa load without changing size.
Disadvantages:
The heat distortion temperature is lower, but the heat-resistant ABS can reach 115°C and the embrittlement temperature is -7°C.
Combustible, general grade ABS combustion rating is only HB; but modified to achieve flame retardant.
Weather resistance is poor, but can be improved by modifying or replacing butadiene in the components.
2. ASA performance advantages
ASA resin is an acrylic rubber-based graft copolymer of acrylonitrile and styrene. Compared with ABS, weather resistance has been changed substantially due to the introduction of acrylic rubber without double bonds in place of butadiene rubber. It is about 10 times higher than ABS; other mechanical properties, processing properties, electrical insulation, chemical resistance are similar to ABS.
The products processed with ASA resin can be used outdoors without surface protection such as painting and plating, and exposed to sunlight for 9 to 15 months. The impact strength and elongation are almost not reduced, and the color is almost unchanged.
Third, the classification and application of ABS and ASA
(I) Classification and Application of ABS
The excellent comprehensive performance of ABS is widely used, but some disadvantages of general-grade ABS also limit its application in some industries; many modified special ABSs are developed for this purpose:
According to the purpose, special ABS can be mainly divided into flame-retardant ABS, transparent ABS, heat-resistant ABS and impact ABS.
1. Transparent ABS
It is a modified ABS grafted with MMA. It has a good overall performance and can be widely used in electronic and electrical parts. Its transparency is close to acrylic (PMMA) and polycarbonate (PC), and the Izod impact strength and falling ball impact strength Similar to general purpose ABS, it is not easy to crack under low impact.
The main application products:
Keyboard keys, computer case, printer cover, mouse, printer or fax paper holders, noise baffles, awnings, cosmetic bottles, artificial nails.
2. Flame retardant ABS
Is a special ABS modified by flame retardant, with excellent flame retardant properties, can be widely used in electrical products shell.
The main application products:
Hair dryer shell, charger, laser printer housing, satellite TV receiver, trademark machine, ATM automatic teller machine, magnetic card credit card machine, PDP TV front panel.
3. Heat-resistant ABS
It is a kind of special ABS modified by heat-resisting agent. It has excellent heat resistance and has a wide range of applications in automotive parts, home appliance parts and other industries.
The following are applications of heat-resistant ABS in automotive and household appliances:
Fan, heater, dryer, camcorder, printer, stereo, charger, navigator, remote control, handle, weeder, meter box, kettle, radio, intercom, oscilloscope.
(B) Classification and Application of ASA
According to the purpose, ASA can be divided into injection molding grade, extrusion grade and heat-resistant grade.
ASA and ABS structural characteristics are very similar, in the structural formula, the butadiene part of ABS is replaced by acrylic acid, which is ASA.
ASA does not contain double bonds, so it can maintain color and performance stability under long-term, harsh outdoor conditions. It also has superior scratch resistance compared to polypropylene polymers.
1. ASA is widely used in the extrusion molding industry because of its excellent mechanical properties, good colorability, excellent weather resistance, good processability, and better thermal stability than PVC.
2. ASA can also be used in the automotive industry, manufacturing rearview mirror housings, ventilation grille and other auto parts. In modern, general, Kia and other well-known auto companies, there have been many successful cases. Main application products: rearview mirror housing and Bracket, ventilation grille, radiator grille.
Fourth, summary
Due to the special structure and composition of ASA resin, ASA has better impact resistance, weather resistance and high temperature resistance than ABS. It has the following advantages in construction and sanitary, automobiles and motorcycles, electrical and electronic engineering, outdoor equipment and sports equipment. Extensive applications. The use of Anqing Petrochemical styrene, acrylonitrile resources research and development of ASA resin, has a broader development prospects.