丙烯腈－丁二烯－苯乙烯三元共聚物(ABS)
Acrylonitrile-Butadiene-Styrene Terpolymer
主要特点：
瓶胚检测机●良好的耐油性、耐水性和化学稳定性。
●电性能良好，其绝缘性很少受温度、湿度的影响。
●金属化薄膜电容器具有良好的模塑性，能着、能电镀、能粘结。 ●无毒，无臭，不透水但略透水蒸气。
●不足之处是耐气候性差，耐紫外线、耐热性不高。
主要用途：
ABS用途广泛，主要用于汽车、飞机零件、机电外壳、空调机、电冰箱内衬打字机、照相机壳，电视机壳安全帽，天线放大器、车灯以及板、管、棒等。
共聚: 将丁二烯/丙烯腈乳液加入到苯乙烯/丙烯腈乳液中，然后沉淀聚合。
接枝共聚: 将苯乙烯和丙烯腈加入到聚丁二烯乳液中。然后搅拌加热，加入水溶性引发剂进行聚合。这样得到的接枝共聚ABS相对与共聚得到的ABS冲击强度大，但刚性和硬度低。
ABS的强度很高，密度小，用它来制造汽车部件，如保险杠，可以降低油耗，减少污染。ABS的强度高是因为丙烯腈上的腈基有很强的极性，会相互聚集从而将ABS分子链紧密结合在一起。同时，具有橡胶性能的聚丁二烯使ABS具有良好的韧性。
尼龙 (Nylon)
投票箱制作
Polyamide
尼龙是最常见的人造纤维。1940年用尼龙织造的长统丝袜问世时大受欢迎，尼龙从此一举成名。此后在二战期间，尼龙被大量用于织造降落伞和绳索。不过尼龙最初的用途是制造牙刷的刷毛。尼龙属于聚氨酯，在它的主链上有氨基。氨基具有极性，会因氢键的作用而相互吸引。所以尼龙容易结晶，可以制成强度很高的纤维。
尼龙分尼龙6,6、尼龙6、尼龙1010等。
其实尼龙6和尼龙6,6，区别不大。之所以两种都生产，只是因为杜邦公司发明尼龙6,6后申请了专利所以其它的公司为了生成尼龙，才发明出尼龙6来。
cgw尼龙的优点与不足：
自动拖把Advantages and Limitations of Nylons
Mechanical Properties
Good combination of mechanical properties- fatigue and creep strength, stiffness, toughness and resilience- only slightly inferior to polyacetals. Limitations are that all nylons absorb or give up moisture to achieve equilibrium with ambient conditions- moisture acts as a plasticizer and decreases tensile and creep strength and stiffness and increases impact strength and the dimensions of the component. The effect is most serious in thin-sectioned components. Because nylons depend upon moisture for impact performance, embrittlement can occur in desiccated air.
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Wear
Good abrasion resistance (ability to absorb foreign particles) and self lubricating properties are responsible for the widespread use in gears and bearings.
Thermal Properties
Suitable for prolonged service temperatures of 80-100C and this can be increased to 140 C with heat stabilized grades. Limitation is that thermal expansion varies with temperature and moisture content.
Electrical Properties
Good commercial insulator but electrical properties are greatly influenced by moisture content and/or temperature increase.
Environmental
All nylons are resistant to fuels, oils, fats and most other technical solvents such as aliphatic and aromatic hydrocarbons, chlorinated hydrocarbons, esters, ketones and alco
hols. All have good alkali resistance. Limitations are that all nylons are attacked by strong mineral acids, acetic acid and dissolved phenols. Some types are dissolved by formic acid. UV attacks un-stabilized nylons causing embrittlement in a comparatively short period.
Food and medicine
Can be used in contact with most food stuffs at room temperature and sterilized by steam or infra-red radiation. Fillers- Wide range of fillers and additives to improve specific properties and reduce limitations of unmodified materials, e.g glass fibre filler greatly reduces effects of moisture on dimensions and properties compared with unfilled materials.
Processing
Most material types are available in grades suitable for injection, blow and rotational moulding and extrusion, with additional possibilities of fluid bed coatings, sintering and ca
sting for special grades. The latter (casting for monomer) is particularly useful for producing large stress-free sections in small economical batches. Most nylons can be readily machined using techniques akin to those used for the light alloys. Nylons can be joined with adhesives, induction bonding and ultrasonic welding. Limitations are that nylons have a sharply defined melting point and high shrinkage values occur on moulding thick sections. Nylons are crystalline; this results in longer cycle times in moulding. Conditioning for moulding is frequently necessary.
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