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塑料和橡胶给产品设计提供了无限的可能；千千万万种塑料和橡胶制品充斥着我们的生活，给设计师，制造商和用户带来了独特的优势。我们往往通过大批量生产来降低塑料制品的成本，但是制造仍然希望塑料的价值可以紧跟自然材料，因此合成塑料也慢慢的进入人们的生活，在触觉和视觉上模仿丝织，皮质和天然橡胶。
There is an almost unlimited choice of plastics and rubbers, many thousand of different types surround us in our everyday lives. They offer unique benefits for designers, manufacturers and users. Certain types can outperform metals in many applications. They are produced in large quantities to reduce cost, but we still hold onto the values associated with natural materials. Therefore, over the year synthetic plastics have been engineered to look and feel like silk, leather and natural rubber. 塑料的种类 塑料由高分子聚合物构成（链状的重复单元），简称高聚物。而合成塑料由石油化学工厂生产。那些不经过石油化学提炼塑形的天然高聚物，我们则称之为有机塑料，有机塑料含有淀粉，葡萄糖和天然橡胶。有机塑料作为可以完全降解的原材料，不需要耗费太多的精力生产。
而通过添加具有生物活性的复合物，不同等级的合成塑料也可以在特定的时间段进行降解，这种复合物不会影响塑料的物理特性，但是可以让有机塑料在1-5年内被地下的微生物消化，很多产品应用了这种塑料，如玻璃瓶，食物托盘和垃圾袋。
TYPES OF PLASTIC Plastics are made up of polymers, long chains of repeating units, which occur naturally. synthetic plastics are produced by the petrochemical industry. some natural polymers are refined and molded without the addition of petrochemicals. these are known as bioplastics, and they include starch - based. cellulose-based and natural rubber materials Bioplasticsrequire less energy to produce as raw materials and are fully biodegradable at the end of their useful life. There are also grades of synthetic plastics available that have been modified to break down within a specified time period. this is made possible by the addition of bioactive compounds, which do not affect the physical qualities of the plastic but enable it to be digested by microorganisms in the ground within1 to 5 years. products made with this material include some clear plastic bottles,food trays and refuse bags. 合成塑料分为2种： 1. 热塑性塑料 2. 热固性塑料
以上二者没有明显的界限，因为某些材料可以既是热塑性塑料，也可以是热固性塑料，取决于他们内部的高聚物结构。例如：聚酯和聚亚安脂，材料可以进行合成，成为二者的复合材料。
如果一定要给二者进行区分，那么区别就在于热塑性塑料的高聚物链之间是交叉相连，这是一种更加牢固的分子结构，有更高的抗热性和抗化学腐蚀性。这种交叉相连的分子链是不可逆的，不可以被重塑。
而热塑性塑料可以被重塑多次（通过裁剪和粉碎处理，且不会影响材料的特性）。其中粉碎处理一般限制在15%之内，但是有些材料具有更高的百分比。 Synthetic plastics are divided into groups: thermoplastics and thermosetting plastics thermosets, The distinction is not always clear-cut because some materials can be both thermoplastic and thermosetting depending on theirpolymeric structure. for instance, polyester and polyurethane Materials canalso be compounded to produce composites of both groups The defining difference between these 2 groups is that thermosetting plastics form permanent cross - links between the polymer chains. this creates a more durable molecular structure that is generally more resistant to heat and chemicals the formation of cross-links means that the curing process is way.they cannot be remoldedThermoplastics can be remolded many times. off cuts and scrap regrind can be reprocessed with virgin material without a significant effect on the properties of the material regrind is typically limited to less than 15% but some materials may contain a much higher percentage.
热塑性塑料通过分子结构和重量会被深层分类，通过不同的材料和生产方式，材料的结构或者结晶度是不同的，例如：如果PET可以快速冷却，那其分子链会变得无序，随机。而如果PET可以缓慢冷却，他的分子链就会变成有序的结晶结构。具有无序分子链的塑料一般是透明的，且对周围环境有较好的抵抗性。相对的，具有结晶分子结构的塑料具有良好的抗化学腐蚀性。 Thermoplastics are further categorized by molecular structure and weight the structure or crystallinity differs according to the type of material and method of manufacture. for example, if polyethylene terephthalatepet is cooled quickly the polymer chains form a random and amorphous structure. however. if it is allowed to cool slowly. the polymer chains form anorderly crystalline structure amorphous plastics tend to be transparent and have greater resistance to impact in contrast crystalline materials tend to have better resistance to chemicals.
多聚物可以组成共聚物和三元共聚物，例如：SAN和ABS。所有三类塑料（有机塑料，热塑性塑料和热固性塑料）都含有橡胶材质。橡胶根据他们的收缩程度进行分类，例如：热塑性的橡胶（TPE）可以和固体热塑性塑料一样被融化处理。常常被用于二次注塑和多点注塑，从而提高固态热属性塑料的质量和特性。
和合成塑料一样，合成橡胶也通过石油化学工厂进行生产。然而，天然橡胶（NR）是由从橡胶树上提取的汁液制成的，常常用于货运汽车和航天飞机的轮胎。
Polymers are blended together to form Copolymers and Terpolymers such asm ABS. All 3 groups of plastic - bioplastics.thermoplastics and thermosets contain elastomeric rubber materials. Elastomers are characterized by their ability to stretch and return to theiroriginal shape. thermoplastic elastomers (TPE) can be melt processed in exactly the same way as rigid thermoplastics. they are frequently over - molded and multi-shot injection molded, onto rigid thermoplastic substrates to harness the qualities of both Like synthetic plastics, syntheticrubbers are produced by the petrochemical industry natural.on the other hand, is produced fr m a saptapped from the para rubber tree and is used to make products such as lorry and aeroplane tyres. 大多数塑料都可以制成泡沫，由特殊的吹制机构完成，根据可塑性和硬度的不同，泡沫也可以分为很多种，泡沫被用于家装，安全和模型制作，同时也是复合层压的核心材料。
Most types of plastic can be foamed. This is carried out with a blowing agent. There are many different types of foam. ranging from flexible to rigid . with either open or closed cells, foams are used for a spectrum of applications such as upholstery, safety model making and as a core material in composite laminating. 塑料的添加剂，填充物和加固剂 添加剂和填充物被用来加强塑料的特性，他们用来提高塑料的色彩，工程属性，导电性和抗菌性，同时也可以提高材料的耐火性，耐UV性和抗化学腐蚀性。
一些塑料，例如PET,PC,PS，是透明的且着色力很好，他们可以使有色的，可以是无色的。 色彩通常来自于塑料母料中带有颜料的载体树脂，
ADDITIVES, FILLERS AND REINFORCEMENT Additives and fillers are used to enhance the properties of plastics. they are usedto improve color, specific mechanical properties, electrical conductivity. moldflow and antimicrobial properties and to increase the material's resistance to fire.UV light and chemical attack. Some plastics, such as polycarbonate.PET are water clear and so take color very well, they can be tinted or opaque. the colors are typically made up of a carrier resin coated in pigment, which is added to the raw material during processing. 潘通色最常见于美国 RAL色是由德国制定的标准 塑料的色彩是由潘通色和RAL色决定的，从而确定了不同地域和不同工厂之间的颜色标准。还有一些特殊颜色，例如金属色，珍珠色和荧光色。 Color is generally determined byeither pantone or RAL. These are recognized international standards and ensurethat the color that is specified by the designer in 1 country is exactly the sameas the color that is injection moldedby a factory in another country. Other color effects that can be achieved inplastics include metallic, pearlescent. thermochromatic, photochromatic and
填充物可以加强塑料的工程属性，例如云母，矿物质，纤维和织物。热塑性塑料可以和填充物一起用于注塑和压塑等。其中在热塑性材料成型中，纤维添加物的厚度不可大于1mm（0.004in）。在热固性塑料的压塑，复合层压和3D热层压中，长且连续的纤维材料可以作为添加剂。 Fillers to improve mechanical properties include talc, minerals, fibre and textiles. thermoplastics can be injection molded, extruded and compression molded with all of these fillers fibre reinforcement long and continuous strand fibre reinforcement is incorporated into thermosets by compression molding. Composite laminating and 3d thermal laminating.
纤维添加剂包括玻璃，芳纶，碳和黄麻纤维。纤维材料作为添加剂可以加强塑料的强度，减轻重量，甚至强度会高于金属材料，因此常常用于船体材料和家具。其中碳纤维是通过将高聚物氧化，拉伸和加热制成的，例如PAN, 需要加热至1500℃。碳化的过程需要经过多次加热工艺，所以会花费巨大的能量。碳纤维材料强度高，重量小，如今已经供不应求，常常被用于体育器具。传统的复合层压需要技术高超的操作人员来完成，所以很贵。但是，由于近来科技的发展，例如树脂传递成型，树脂注入成型，是整个制造过程更加快速，人力成本更低。 The types of fibre used include glass,aramid carbon and more recently hemp and jute. fiber reinforced compositematerials have superior strength for their weight, several times greater than metal, and different grades aresuitable for everything from boat hulls to lightweight stacking furniture. Ccarbon fibre is manufactured by stretching and heating in controlled atmosphere. the process carbonization takes places stages of heating and so requires a greatdeal of energy eventually long ribbon most pure graphite are formed. and the width of ribbon will affect the strength of the carbon fibre there are different grades strengths of carbon fibre. which depend on the manufacturer Carbon fibre has very high strength to weight and as a result of its own is becoming more difficult to purchase because production cannot keep up with and it is a relatively expensive material but is becoming more widespread in consumer products such as sports equipment this is partly due to the added value that carbon fibre brings application, but also as a result of improved manufacturing techniques. including recent breakthroughs in recycling methods. traditional composite laminating requires a great deal of highly skilled labor and is therefore very expensive. new techniques are now being used, such as resin transfer molding and resin infusion page which: more rapid and mechanized and so reduce labor costs considerably 相关推送
10种塑料成型工艺
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