What Is The Future Development Direction And Application Prospect Of Flame Retardant Plastics For Automotive Parts?

What Is The Future Development Direction And Application Prospect Of Flame Retardant Plastics For Automotive Parts?

Outline

1. Future Development Direction of Flame Retardant Plastics for Automotive Parts

2. Application of Flame Retardant Materials in Automotive Parts

-Flame Retardant PP

-Flame Retardant ABS

-Flame Retardant PC

-Other Flame Retardant materials

3. Future Research Focus on Flame Retardant Materials

-Flame retardant theory research

-Development of high performance flame retardants for plastics

-Improvement and optimization of auto parts materials

-Enhance the promotion of flame retardant materials and products legislation

One of the most critical trends brought about by the rapid development of the automotive industry is lightweighting, and nowadays the use of various modified plastics, composite materials and lightweight alloy materials is becoming more and more mature, and a variety of plastics can be seen both around the engine of a traditional automobile and on the power battery of a new energy vehicle. However, the performance of these materials on the safety issue of flame retardancy is not as good as it should be. That's why flame retardant and its 

related industries have been clamoring for discussion in recent years.

Today we will take a look at the future development direction of flame retardant materials from the perspective of automotive components, and what applications various flame retardant materials have.

Future Development Direction Of Flame Retardant Plastics For Automotive Parts

At present, the common types of flame retardant materials used for automotive parts are PP, PA, PU, PC, ABS materials, as well as a variety of modified materials and composites composed of them.

Compared to traditional fuel vehicles, new energy vehicles have added battery pack modules, charging piles and charging guns and other components, the use of engineering plastics for a single new energy vehicle battery pack module is about 30kg, and the plastic shell of new energy vehicles is currently mainly used for modified PP, as well as modified PPS, PPO, and other high-temperature resistant plastics. Charging pile due to the higher use of standards and harsh use of the environment of engineering plastics demand, each charging pile about 6kg of engineering plastics, the current common main PBT, PA and PC.

The increase in car ownership has led to numerous spontaneous combustion and fire accidents. Therefore, when the material is used in automobile parts, it is necessary to consider whether the flame retardant and fire retardant performance of the material can meet the national standards. Generally speaking, most of the flame retardant plastics are prepared with their limiting oxygen index LOI raised to about 25-35% in order to effectively improve the overall safety index of automobiles. In addition, coupled with the current dual background of electrification and carbon neutrality, plastics such as petroleum-based products, as well as a variety of halogen-containing flame retardants, will be subject to more restrictions.

Therefore, the future direction of the development of flame retardant plastics, in addition to the need for adequate mechanical properties to meet the demand for lightweight, electric vehicles and other fields will also require materials to focus on flame retardant, electrical, processing, environmental requirements.

Application Of Flame Retardant Materials In Automotive Parts

At present, the application of polymer materials can be seen everywhere in automotive load-bearing parts, new energy vehicle battery packs and other automotive parts. The application of polymer materials in automotive parts, as well as the need to enhance automotive safety, has promoted the development of flame retardant polymer materials.

The current application of flame retardant polymer materials are mainly PP, PU, ABS and PC-based, according to the special needs of automotive parts and components are also corresponding to the use of composite materials (alloying), PA, PBT and PMMA and other materials.

• Flame retardant PP

PP is the most used polymer material in automotive plastics, with excellent chemical resistance, and simple and low cost processing. At present, it is widely used in automobile instrument panels, battery pack shells, door guards, pillars, seat guards, bumpers and so on.

However, due to the lack of flame retardant PP flame retardant performance is very poor, its LOI is only 17. 8%, very easy to burn. Domestic and foreign research on PP for automotive flame retardant mainly centers on the modification of the polypropylene matrix, and at the same time, by adding low-toxic, halogen-free flame retardants, the development of polypropylene composites with excellent mechanical properties and flame retardant efficacy, in order to meet the flame retardant needs of automotive parts. At present, the flame retardants applicable to PP are mainly additive flame retardants, with more applications of halogenated flame retardants (e.g. brominated flame retardants, bromine-antimony synergistic flame retardant system), inorganic filled flame retardants (e.g. magnesium hydroxide, aluminum hydroxide), phosphorus and nitrogen (e.g. MPP, APP, MCA, phosphonitrile, phosphate ester, etc.) as well as intumescent flame retardants (IFR).

As we said above, with the implementation of stringent environmental protection policies, the halogen-free flame retardants for polymer materials has been a major trend. In terms of specific cases, there are examples of LGF reinforced halogen-free flame-retardant polypropylene battery cells made of PP as the substrate, long glass fiber (LGF) as the filler material, and phosphorus and nitrogen halogen-free intumescent flame retardant (IFR), MCA, etc. The preparation process uses dual masterbatch.

The preparation process adopts the dual-masterbatch preparation method, through the preparation of LGF masterbatch and halogen-free flame-retardant masterbatch, respectively, and the two are mixed homogeneously and directly injection molded to obtain flame-retardant PP products. The dual-masterbatch preparation method avoids the problem of degradation of flame retardant caused by high temperature in the shear zone during the manufacturing process of LGF masterbatch due to excessive shear, and the problem of degradation of mechanical properties caused by the short length of glass fiber. In the halogen-free modification technology of flame retardant PP, IFR is considered to be one of the most promising development directions of halogen-free flame retardant PP because of its minimal impact on PP processing fluidity and low-density advantages, excellent flame retardant efficiency, low dosage, low smoke and non-toxicity, and other advantages.

Flame retardant PP started late in China, but is developing rapidly. Especially in recent years, the rapid growth of the new energy automobile industry has directly contributed to the rapid growth of the demand for flame retardant PP, and many domestic universities, research institutions and enterprises are involved in the development of flame retardant PP for automotive parts.

In the future, the research of automotive flame retardant PP will focus on high efficiency and environmental protection, through the selection of halogen-free flame retardants, intumescent flame retardants, phosphorus and nitrogen flame retardants, as well as complex flame retardants while combining with other additives, the development of flame retardant PP materials with excellent performance.

• Flame retardant ABS

Before the rise of ABS in the automotive industry, it was also one of the world's largest amount of polymer materials for home appliances. According to incomplete statistics, about 80% of China's ABS consumption comes from the field of home appliances, and this is mainly due to the outstanding surface coating performance, durability and corrosion resistance of ABS. It is also these characteristics that make ABS typical in the field of automotive painting. However, the molecular structure of ABS resin has only three elements, C, H and O, so it does not have flame retardant properties, and its stability at high temperature stage is very poor, and it is very easy to burn. At the same time in the combustion process will also produce pungent odor and black smoke, can not be directly used for automotive parts.

At present, the main direction of application of ABS is through the flame retardant or high temperature modification, or co-mingled with PC into PC / ABS composite materials, which will also be described in detail below. For ABS, halogenated flame retardants have higher flame retardant efficiency, of which bromine flame retardant effect is better than chlorine. Although halogen flame retardant is low cost and effective, it is well known to practitioners that halogen flame retardant will face great pressure from policy and environmental regulations in the future.

Therefore, the flame retardant modification of ABS is still an important R & D direction. But then again, for applications with strict flame retardant standards, bromine flame retardants are still the most mainstream choice. It is reported that about 70% of ABS used in electronic and electrical products are brominated flame retardants. PC/ABS has the advantages of both, with better HDT and stability, processing performance is also better, is now the largest production, the most mature technology of plastic alloys, but also in the field of automotive parts is currently one of the most widely used materials. Such as automotive instrument panels, battery packs, body, interior and other parts, are used in PC / ABS materials.

However, it should be noted that in some indicators or “1 +1 <2” situation: PC itself is a self-extinguishing material, UL94 up to V2 level, but the flame retardant properties of PC / ABS has declined, the need to make up.Currently used in addition to halogen and phosphorus systems, it is worthwhile to pay attention to the direction of the development of nano-flame retardants, such as nanoscale antimony trioxide, aluminum hydroxide, magnesium hydroxide, and nano-layered double hydroxide and so on.

• Flame retardant PC

As one of the five major engineering plastics, PC is also quite maturely used in automotive parts, such as automotive instrument panels, lamp systems, heating panels, defrosters and even bumpers made of some PC alloys, and so on. As we have just said, PC itself has a certain degree of flame retardancy, compared with other polymer materials (such as PE, PP, etc.) has a certain advantage, LOI can be 21-24%. However, for automotive parts with relatively high flame retardant requirements in the application field, its flame retardant performance is still difficult to cope with, and still need to be flame retardant modification.

Bromine flame retardants can significantly improve the flame retardant properties of PC, commonly used decabromodiphenyl ether (DBDPO), tetrabromobisphenol A (TBB-PA) and so on. However, bromine-containing flame retardant materials are prone to decompose and produce corrosive gases at high temperatures, causing damage to automotive parts. In addition, the addition of bromine flame retardants will seriously affect the transparency of PC, but also does not meet the requirements of the European Union halogen-free, environmentally friendly policy. Currently, the most used phosphorus-based flame retardants in industrialized PC products are mainly TPP, RDP and BDP.

Among them, TPP is solid at room temperature, poor thermal stability, easy to volatilize in PC processing temperature, only play the role of gas-phase flame retardant, RDP and BDP at room temperature for the liquid, with good thermal stability, can play a gas-phase and solid-phase flame retardant effect at the same time, at the same time, BDP and PC have a better compatibility, can play the role of hardening growth rate, so the PC + BDP system has become the use of more of a system! Therefore, PC+BDP system has become a more widely used system, and the proportion of BDP added is about 10%. In addition, silicone compounds as a new generation of environmentally friendly flame retardants, due to its high efficiency, low toxicity, non-polluting properties, as well as less impact on the processing performance and physical properties of PC is also gradually gaining attention, such as polysilanes, polysiloxanes and so on.

PC for automotive parts in the selection of flame retardant is also close to the halogen-free environmental protection, through the addition of a variety of additives or the preparation of composite flame retardants and other ways to enhance the comprehensive performance of PC. In addition, PC and ABS, PBT, etc. through the composition of composite materials is also to enhance the processing performance of PC and flame retardant properties of the choice.

• Other flame retardant materials

PP, PU, ABS and PC are flame retardant polymer materials mainly used in the production of automobile parts. In addition, the composite materials prepared by melt blending two or more polymer materials are also a kind of materials used more often at present, such as PC/ABS, PC/PBT, PC/FR composites and so on.

Specifically to the case, Polymaker launched three PC-based 3D printing materials, which will be used for the production of automotive parts, three products are Polymaker PC-ABS, Polymaker PC-PBT, PolyMax PC-FR, these three products have their own characteristics, in terms of heat resistance, impact resistance, ease of processing, and flame retardant properties, all have a good performance. All three products have good performance in terms of heat resistance, impact resistance, ease of processing, and flame retardancy.

Polymaker PC-PBT is based on the Makroblend® product line of Costron, which has been improved to enhance the overall performance of the material. Similarly, PolyMax PC-FR has improved its flame retardant properties on the Makrolon® series of products of Costron, making the material UL94 to reach V0 level, and the material is used in the battery casing of new energy automobiles.

Future Research Focus on Flame Retardant Materials

• Flame retardant theory research

Relevant researchers should apply the methods, mechanisms and standards of material flame retardant research to the study of flame retardant performance of automotive polymer materials according to the characteristics of automotive parts and applications, and explore how to improve the flame retardant performance of polymer materials for automotive parts.

• Developing high-performance flame retardants for plastics

Flame retardants for polymer materials for auto parts should be developed in the direction of halogen-free and high-performance in the future, and the focus of the research on high-performance flame retardants will be on the development of compounding and synergistic flame retardant technology, halogen-free flame retardant, intumescent flame retardant, ultrafine, nanoscale technology, high-efficiency surface chemical modification technology, and multifunctionalization technology.

• Improvement and optimization of auto parts materials

At present, the domestic modified plastics still have a high technical threshold, not only in the strength, hardness, toughness and other basic requirements of the standard and then improve, while in the electrical properties, health and safety performance as well as environmentally friendly performance and other aspects of the new requirements are also constantly put forward, automotive parts polymer materials will be toward the performance of high-end, customized functional direction.

High-performance flame retardant is not enough, but also need to improve the special properties in order to enhance the comprehensive performance of flame retardant polymers for automotive parts.

• Enhance the promotion of flame retardant materials and products legislation

At present, there are no sound laws and regulations in the field of automotive flame retardant and test methods, in order to better serve and promote the development of automotive parts flame retardant industry, the development of a more effective automotive parts with flame retardant polymer materials test methods and product regulations will be of great significance.

Conclusion

In the current research and application of flame retardant materials for automotive parts, Yinsu Flame Retardant is also actively promoting innovation and has developed a variety of high-performance flame retardants. These flame retardants include red phosphorus (PPV0-P-32M) and piperazine (PPAP-15) flame retardants for polypropylene (PP), which not only enhance the flame retardancy of PP, but also ensure its stability under high temperature environment. In addition, for ABS materials, Yinsu Flame Retardant has developed high-impact red phosphorus and antimony composite (T3) flame retardants, which effectively enhance the impact resistance of ABS, while meeting stringent flame retardant standards. These innovations from Yinsu Flame Retardant provide safer and more environmentally friendly material choices for the automotive industry, and promote the lightweighting and safety enhancement of automotive parts.