At present, my country's auto industry has entered a stage of rapid growth, with both production and sales exceeding 18 million vehicles, ranking first in the world. Driven by the rapid growth of the automobile industry, a high-growth industry group related to automobiles has been formed, and the non-metal material industry represented by plastics is one of this industry group. As an important variety of automotive materials, the output value of automotive plastics is growing, and its technological development trend is also attracting more and more attention from the industry.
So, what is the technological development trend of automotive plastics? This needs to be seen from the direction of the entire car development. As future cars are smarter, more comfortable, lower carbon and cheaper, the development trend of automotive plastics can be roughly classified into the following aspects: functionalization, light weight, greening, and a balance between low cost and high quality.
Functional
According to Sina.com's survey and analysis of consumers' car purchases, the appearance, color and interior design of the car have become one of the important factors for consumers to buy a car, second only to price and safety. Since the price and safety of automobiles have not changed relatively much, the comfort and aesthetics of automobiles is one of the contents that consumers pay more attention to. The comfort and beauty of the car is inseparable from the increasingly high functionality of materials. From the perspective of consumers' requirements for interior and exterior decoration, the functional trend of automotive plastics is reflected in many aspects such as low odor and color diversity.
The low odor of interior materials is a hot spot that consumers pay attention to recently. The smell of a new car has become an important factor for consumers to buy a car. Although my country has not yet developed a special testing standard for air pollution in automobiles, many domestic automobile companies have begun to conduct special research on the issues of materials and installation techniques in automobiles. In view of the fact that internationally renowned auto OEMs have strict odor and volatile gas test standards for the materials used in automotive interior parts, and these standards are becoming more and more stringent with the improvement of consumer demand; Industry-related standards are also increasingly in line with developed countries, and the low odor of automotive interior materials must be a significant trend in the past 5 to 10 years.
The color of interior materials began to show a trend of diversification. The traditional interior colors are mainly matte black and beige, which is mainly for driving safety - low gloss, cool tones, so that the driver's eyes are not easy to fatigue. However, under the premise of ensuring safety, the color of the interior is now more and more user-friendly to meet the needs of different consumers. For example, high-gloss color effects such as piano black and moonlight silver are used on sports models. These high-gloss colors are mainly used in locations that do not interfere with the driver's view, such as parts below the waistline of the dashboard, sub-dashboards and door panels. Its main design concept is to enhance the grade of the interior and bring freshness to consumers. The interior with bright tones such as orange red and bright yellow not only attracts the attention of the owner when purchasing, but also can adjust the driver's mood in the normal driving environment, making his mood happy and excited. At present, these bright colors have been widely used on seats, and they have also begun to be used on the decorative strips of instrument panels and sub-dashboards. The diversity of interior material colors requires the base resin to have good post-processing, dyeability, and weather resistance.
Antistatic materials are also one of the development trends of automotive interior materials. Plastic has high resistivity and low dielectric constant, which is easy to be electrified by friction, and the charge is difficult to be conducted away, so it is easy to produce electrostatic dust collection, spark discharge in dry environment and other undesirable phenomena. In order to solve this problem and improve driving comfort, Volkswagen of Germany has required some automotive interior parts to have the highest antistatic function since 2009. These interior parts include parts that are often touched by hands, such as the frame of the interior rearview mirror and the glasses case on the ceiling, etc. The materials used are antistatic plastics such as PC/ASA and PA/ASA alloys.
Based on its lower density and cost, polypropylene has been widely used in automotive interiors for many years. However, polypropylene materials also have certain problems. For example, the surface of mineral-filled polypropylene materials is easy to be scratched and whitened, which affects the use of consumers. In recent years, this phenomenon has been greatly improved, but some scratch-resistant polypropylene materials have the bad phenomenon that the surface is easy to stick. Therefore, a future development trend of polypropylene filled materials is not only good scratch resistance, but also no bad hand feeling. In addition, due to the customer's tactile needs, the car interior will increasingly use soft instrument panels. This also means that foam materials and TPO materials will have more applications.
Plastic materials that can be chrome-plated (mainly PC/ABS, ABS materials) are currently widely used in the interior and exterior of automobiles, such as automobile logos, radiator grilles, rearview mirrors, gear trims and hubcaps, etc. Compared with metal, plastic electroplating products can not only achieve a good metal texture, but also reduce the weight of the product, effectively improve the appearance and decoration of plastic, greatly improve the degree of freedom of design, and improve its electrical, thermal and corrosion resistance. performance. Chrome-plated products are widely used in high-end cars because of their high-quality image. For example, Shanghai GM even added electroplated "eyebrows" to the rear lights for the new LaCrosse models launched in 2009 to highlight the fashion sense of a new generation of premium cars. Recently, this application has been expanded from B-class cars to A-class cars, such as Yinglang, which was subsequently launched by Shanghai GM, and began to use chrome-plated materials on a large scale. This means that electroplating-grade plastic materials will be used more in automotive exterior parts.
As consumers are more willing to have more open contact with nature and the sky, consumers have a stronger demand for sunroofs, especially panoramic sunroofs. At the same time, this trend also makes it possible to use plastic materials to replace glass on a large scale, because the use of transparent plastic materials (such as PC materials) can bring greater design freedom, making skylights with larger opening sizes and larger effective opening. It is believed that in the near future, the all-plastic panoramic sunroof will be widely used in production vehicles.
As the post-80s and post-90s people have become the main people who buy vehicles, sports models and sports cars have become
A new choice for young people, and a distinctive feature of sports models and sports cars is the use of plastic spoilers (tails). The main function of the spoiler is to reduce the lift of the rear of the vehicle. If the lift of the rear of the vehicle is greater than that of the front of the vehicle, it is easy to cause the vehicle to oversteer, reduce the grip of the rear wheels and deteriorate high-speed stability. Since most of the plastic spoilers are made of blow-molded ABS after molding and spraying, blow-molded ABS materials will be more used in automotive spoilers.
Lightweight
Another main direction of the development of automotive material technology is to make the car lighter. Reducing the weight of the car is one of the more effective measures to reduce vehicle emissions and improve fuel efficiency. For every 10% reduction in the car's own weight, the fuel consumption can be reduced by 6% to 8%. It is expected that in the next 10 years, the weight of the car itself will continue to be reduced by 20%. In addition to the use of high-strength steel and aluminum-magnesium alloys, the development and application of new lightweight plastic materials is an important means of reducing automobile weight. At present, "replacing steel with plastic" has expanded from automobile structural parts to the interior and exterior trim parts of the entire automobile.
In interior materials, a significant trend is the application of LFT materials. LFT is the abbreviation of "Long-FiberReinforceThermoplastic" in English. It is translated into long fiber reinforced thermoplastic in Chinese, and is also used to be called long fiber reinforced thermoplastic composite material. It is a new type of advanced lightweight material in the field of fiber reinforced polymers. According to the latest statistics, the LFT consumption of the automobile industry accounts for about 80% of the total consumption of the world's LFT industry. Among them, LFT consumption in Europe and the United States accounts for about 95% (Europe accounts for 80%, and the United States accounts for 15%). LFT materials are currently mostly used in automotive interiors are PP long glass fiber reinforced materials, which are mainly used in soft instrument panel skeletons. Long glass fiber material not only has good rigidity and strength, but also its impact strength is much higher than that of short glass fiber filled materials in the past. This glass fiber reinforced material has begun to be used in large quantities in automotive door inner modules to replace the steel of the past. Because the long glass fiber reinforced material can not only reduce the weight of the whole part, but also greatly improve the design freedom, which facilitates the design of engineers. The thin wall of interior parts will also reduce the weight of the car. At present, the average wall thickness of interior parts has been reduced from 3mm in the past to about 2.2mm now, and there is a trend of thinner. Since thin-walled materials require higher modulus and fluidity, long-glass fiber reinforced materials will find more applications in thinner and lighter interior parts. By the way, by combining high and low temperature cold and hot forming (heat and cold) technology, the long glass fiber reinforced material can also better realize the use of the A-level surface of the part. For example, for instrument panel defogging grille products, PBT/ASA+15%GF materials are used to replace traditional PC/ABS materials, and the matte effect can be achieved directly through materials and molds without secondary spraying.
Among the exterior materials, there are more cases of "replacing steel with plastic". In recent years, the front-end modules of bumpers have begun to use PP long glass fiber reinforced materials; Luggage supports on SUV models are more and more made of engineering plastics; PA/PPE materials that can be electrophoretically painted together with the body-in-white have also been applied to the fenders, such as many models of Dongfeng Peugeot Citroen Both use this plastic fender. It is worth noting that the trend towards the use of plastic fenders has become increasingly evident in the automotive industry.
In the parts around the automobile engine, the trend of "replacing steel with plastic" is even more significant, including many parts such as intake manifold, automobile engine cover and fuel tank. The materials usually used for these parts are mainly nylon glass fiber filled materials.
green
Green manufacturing has increasingly become the main development direction of the automobile manufacturing industry. Especially since the European Parliament and the Council of the European Union passed the ELV-related Directives (Waste Vehicles Directive 2000/53/EC and Automobile Directive 2005/64/EC on Formal Approval of Recyclability), the design, material selection and Manufacturing and so on put forward higher requirements. According to ELV's recycling directive, from January 1, 2006, at least 85% of the average weight of each scrapped car should be able to be reused, and the material recovery rate should be at least 80%. From January 1, 2015, these two indicators will increase to 95% and 85%, respectively. This means that the design of auto parts and the selection of materials should follow the principles of easy recycling. Therefore, the general development trend of non-metallic materials for automobiles is sharing, that is, the concentration of materials. Of course, the choice of materials should be as far as possible to choose recyclable thermoplastic materials, that is, use as little and no thermoset materials as possible. Therefore, from the perspective of recycling, thermoplastic materials will be more widely used in the interior and exterior of automobiles, so that the centralization and sharing of materials is logical. In recent years, the sharing trend of interior materials, especially modified polypropylene materials, is more obvious. Of course, the driving force for the mass use of polypropylene materials is not only affected by the ELV-related directives, but more importantly, through the sharing of polypropylene materials, on the one hand, it reduces the cost and cost of non-metallic materials used by OEMs. Management costs; on the other hand, the lower density and higher fluidity of polypropylene materials are more conducive to reducing the weight of parts and improving manufacturability.
Balance of high quality and low cost
The balance between high quality and low cost is not only the design requirement of automobile OEMs, but also the development direction of automobile materials. How to achieve a balance between high quality and low cost is one of the focus issues that auto OEMs at home and abroad pay more attention to. Usually, domestic joint venture brand car factories have a "VAVE" process, that is, to reduce costs through the improvement of technology. The more commonly used means is to realize the localization of raw materials. It is precisely because of the participation of large-scale domestic material suppliers that it is possible to reduce the total cost of automobiles. However, it is not enough for auto OEMs to only consider unilateral cost reduction of raw materials, because the reduction of raw material costs is limited, and the reduction is generally between 10% and 20%. And if the materials used can be innovated or the system cost can be reduced, the cost savings of components can reach 50% or more.
At present, the "paint-free solution" used to manufacture the interior and exterior of automobiles is a good way to reduce system costs. In the past, automotive interior materials usually used the method of painting plastic substrates to achieve the function of interior aesthetics. Surface decorative paint can not only protect the resin substrate, but also achieve high-gloss, matte and other surface effects, and at the same time achieve functions such as weather resistance and scratch resistance. However, the spraying process also brings some problems: First of all, the process is relatively complicated. After the injection of the blank parts, basic links such as transportation, pretreatment and painting need to be added. Some spraying processes also require primers, topcoats and UV curing paints. There are multiple production processes; secondly, the defective parts produced in each process are not easy to peel off because the thermosetting paint has been sprayed, which makes it difficult to recycle later and pollutes the environment; thirdly, the interior parts use non-recyclable thermosetting paint, which also meets the ELV decree The requirements posed a challenge; in the end, the use of paint typically doubled or even tripled the cost of the entire part.
Now, with the development of materials and mold technology, the use of spray-free materials to directly inject parts (MoldInColor) to meet the requirements of OEMs has become a new trend in interior applications. There is no need to worry about the orange peel phenomenon on the surface of the spray-free product. Even if there is damage, there will be no exposed bottom phenomenon (there is a significant color difference between the substrate and the topcoat). At present, many material manufacturers have launched a series of non-spray matt resins for automobiles, which include low-gloss PC/ABS, low-gloss PA/ASA and PA/ABS, low-gloss heat-resistant ABS and PBT/ASA glass fiber filled materials. These materials have been applied to automotive interior parts such as steering column covers, glove boxes, sun visor trim frames, sun visors, pillar trims, and dashboard covers on both sides.
In the future, in response to the diversified development needs of automobile interiors, raw material manufacturers will also introduce high-gloss (such as piano black) materials for automobile interiors and special effects (similar to metallic paint effects) and other spray-free resins. Chemical design provides systematic material solutions.
In the application of exterior decoration, the spray-free solution is also very useful, and the scope of application is gradually expanding. For example, the use of ASA and PMMA materials in door exterior trim pillars (A, B, C pillars) is a typical case
