Automotive plastics is a major trend in the international automobiles manufacturing industry. At present, the demand for vehicle market has shifted to lighter weight sports utility vehicles, minivans and other light vehicles, which will promote the development of vehicle materials to a lighter level. The light vehicle market of resin such as polypropylene, nylon, polyurethane and other engineering plastics demand is very large, accounting for more than 30% of the total resin market demand; demand for polyvinyl butyral accounted for about 85% of its total demand. The latest research report, increase power transmission and trim applications will promote the development of automotive plastics market to 2022, market capitalization of $53 billion (34 billion pounds).
By 2020, the amount of automotive plastics will be 1/3
For more than 30 years, the application of plastics in automobiless has been increasing. At present, the amount of automotive plastics in industrial developed countries accounts for 8%~10% of the total plastic consumption. From the perspective of materials used in modern cars, the shadow of plastic production can be seen everywhere, whether it is external decoration, interior decoration, or functional and structural parts. Application of outer decoration is plastic instead of steel, reduce vehicle weight, the main components of a bumper, fender, wheel cover, guide plate; the main components of internal decoration with dashboard, door inner panel, side panel, glove box cover, seat, rear fender; function and main structure there is a mailbox, radiator water chamber, air filter cover, fan, etc..

Experts expect that by 2020, the average plastic consumption of automobiless will probably reach more than 500kg/ vehicles, accounting for more than 1/3 of the vehicle’s material.
The developed countries is the amount of plastic used in automotive industry, as an important symbol to measure the level of design and manufacturing level of the car, each car plastic content from the last century, in 90s 100 ~ 130kg increased to 152kg in 2004 and 174kg in 2006, now the amount is 230kg, the largest amount of German cars, accounting for more than 15% of vehicle materials. Experts expect that by 2020, the average plastic consumption of automobiless will probably reach more than 500kg/ vehicles, accounting for more than 1/3 of the vehicle’s material.

The domestic production of cars in the use of rubber material and abroad there is a big gap: China’s economy cars per plastic dosage is about 50~60kg, heavy truck up to 80kg, far behind the developed countries the average per vehicle weight of more than 300kg (maximum is 375kg), accounting for 20% of vehicle quality level; China senior car plastic dosage each for 100~130kg, only reached the last century level of developed countries. With the progress of the processing technology of plastic parts and the need of automobiles lightening, the proportion of plastic to the whole vehicle will continue to grow.
In the future, the scientific and technological content of plastic will be higher, and the application will be more extensive.
Automotive plastics will certainly become a major trend in the future
First, the biggest advantage of using plastic for automotive materials is to reduce the weight of the car body. Lightweight automobiles industry is the pursuit of the goal, this can be the Wei Daxian plastic. The proportion of general plastics is 0.9~1.5, and the proportion of fiber reinforced composites is not more than 2. In metal materials, the proportion of A3 steel is 7.6, brass is 8.4, and aluminum is 2.7. This makes the plastic the first choice for automobiles lightening.

In addition to the body, auto parts and trim of car lightweight, energy saving, safety, comfort and other targets also contributed, such as polycarbonate (PC) resin window can be reduced by 3.4 kg; intake manifold injection molding can work long time in high temperature of 220 DEG C, and can withstand high pressure; by thermoplastic polyurethane inflatable bumper can restore the prototype from the 20 mm compression deformation; immediately rebound, by using glass fiber reinforced polymer made suspension spring can reduce the weight of the chassis system, make driving more accurate, reduce the vibration so as to improve the comfort. A kind of PLA nano clay reinforced bio – based plastics has been developed successfully.
Research shows that the vehicle weight is reduced by 10%, the amount of fuel consumption will be reduced by 6%-8%, while the carbon fiber reinforced plastic strong light, not only about 50% lighter than steel, lighter than aluminum of about 30%, there is a superior energy absorption capacity, so it is a significant impact, help to achieve lightweight vehicles.
Second, the plastic molding is easy, making the complex parts processing very convenient. For example, the instrument table is processed with steel plate, and it is often needed to process each part first, then assemble or weld with the connector, and the process is more. And the use of plastic can be formed once, processing time is short, the accuracy is guaranteed.
Third, the elastic deformation characteristics of plastic products can absorb a lot of collision energy, which has a great cushioning effect on strong impact, and plays a protective role for vehicles and passengers. Therefore, the modern automobiles uses the plastic dashboard and the steering wheel to enhance the buffering effect. Plastic materials are used in front and back bumpers and body decorations to reduce the impact of external objects on vehicle sound. In addition, the plastic also has the effect of absorbing and attenuating the vibration and noise, and can improve the comfort of the ride.

Fourth, the corrosion resistance of the plastic is strong, and the local damage will not be corroded. As soon as the steel production is damaged or the anticorrosion is not good, it is easy to rust and corrode. The corrosion resistance of plastics to acid, alkali and salt is greater than that of steel plate. It is very suitable to use plastic as body cover. It is very suitable to be used in large polluted areas.
Fifth, plastics can make plastic according to the composition of plastic, add different fillers, plasticizers and hardeners, change the mechanical strength and processing performance of materials, so as to meet the requirements of different components on the vehicle. For example, the bumper should have considerable mechanical strength, and the cushion and back of the cushion should be flexible polyurethane foam. More convenient is the plastic color can be used to jump out of different colors, save the trouble of spray paint. Some plastic parts can also be electroplated, such as ABS plastics have good electroplating performance, can be used for the production of decorative strips, signs, switch knobs, wheel decorative cover and so on.
High functional plastics are getting more and more applications in automobiless. The use of plastics helps to reduce the weight of cars. The fuel economy can be increased by 5% when the vehicle weight is reduced by 10%. Automotive manufacturers adapt to plastics instead of traditional steel materials, which can also reduce the cost. Plastic can improve the flexibility of the car manufacturer’s design. The successful application of plastics in automobiles to automobiles cost can be reduced, a simple injection mold plastic parts can have many metal parts welded together, plastic can be molded into more complex shapes than steel assembly, can reduce the number of components used in the integration process. Plastic parts for injection are also aesthetical, while traditional materials such as steel and glass are hard to achieve, such as glass headlamp lens and polycarbonate.

Environmental power is pushing automobiles manufacturers to use plastic – based automotive glazes. Fuel consumption and carbon dioxide emissions are the key considerations in many automobiles manufacturers’ assessment projects. The application development information shows that the environmental benefits of using polycarbonate (PC) instead of glass include weight, safety and design. 1 kilograms of PC glaze can replace 2.2 kilograms of glass, and for 150 thousand kilometers of service life (the average consumption of cars in the US), it can save 200~300 trillion coke and reduce 14~22 kilograms of carbon dioxide emissions.
The popularization of automotive plastics is still not ideal
Although there are many advantages of automotive plastics, it is not ideal to promote the market at present. For the reason, over 20% of consumers have misunderstandings on the security market. Some suppliers have some car companies in the development of secret sorrow: try to use the concept of plastic products, give the approval to its quality and reliability in testing, but production is given the abandoned, mainly because of the current market and promotion of new cognitive pressure. It is true that in the concept of consumers, plastics are slightly thinner than steel in impact on impact. Even some media also have the prejudice of “plastic not up to grade insecurity”.
In fact, the improvement of material quality and technology makes the material not lose to metal in strength, hardness, impact resistance and so on, and at the same time, the elasticity of materials cannot be achieved by metal. Professor Wang Hongyan of Tongji University Automotive Institute said that the body in the safety design to absorb part of impact energy through the deformation of the structure, the plastic body, as long as the structure is reasonable in design and manufacturing process properly, its safety should be better than metal material body.
More than 40% of consumers believe that there are obstacles to the promotion of automotive plastics, and the biggest problem is the supply of high strength and cost-effective materials. In this regard, Wuhan University of Technology doctoral tutor School of Automotive Engineering School professor Xun said: the performance of automotive plastics has yet to be improved, such as fatigue plastic itself than short metal, especially when exposed to high temperature environment and exposed to gasoline, the aging phenomenon is particularly serious, and the application in gear or other power transmission parts, can not reach the metal the strength. The Deputy Secretary General of the national technology innovation strategic alliance automotive lightweight long Wang Zhiwen is put forward, the current high-end materials have long been subject to the monopoly of foreign technology, resulting in high cost of products, the use of forcing some companies to abandon high-end materials in the car, which is not in line with the market positioning of domestic models, need to reduce the cost of high-end materials production enterprises, at the same time we need at home enterprises to increase R & D, to achieve technological breakthroughs.

In addition, automotive plastics are also faced with the cost of production transformation, recovery and other problems. In general, people’s recognition of their advantages is far greater than the problem. 而节能政策及产品成本的压力，使其已成为大势所趋，要解决以上问题、推进其发展尚需要政府机构、车企、零部件供应商、材料生产商等多方努力，才能使标准更加完善、技术更加臻熟，消费者安全进一步得以保证。
It is predicted that in the near future, the manufacture of automotive plastic parts will become a new plastics industry, which not only expands the scale of plastics industry, but also determines the development trend of automobiles manufacturing industry in the future.