Prospects for the development of polyurethane tires

In the automobile tire components of occupies a very important position of the vehicle traveling a great impact on performance. Rubber tires in the process of exposing the use of a short life, less wear and tear strength, and other shortcomings, particularly truck tires, as a result of weight-bearing capacity is limited, often leading to the occurrence of the phenomenon of tire. Rubber tires high cost of investment in production equipment, and some of the procedures manual to be used, even the very shape of high-level equipment, manufacturing quality and the quality of each product can not be completely uniform. In addition, the use of rubber tires in the process will have a lot of waste, scrap recycling after it is very difficult to easily give rise to environmental pollution. In contrast, the tires of pouring a small investment in equipment, technology is simple, the process of production problems was relatively small, due to the use of low-density flexible materials, so the weight of tires can be reduced by 25%, casting the tire temperature is also moving lower, In addition, the cast can reuse the material. The following polyurethane tires on the development and application of materials to make a presentation.

Polyurethane tires Research and Development

Polyurethane tires to develop polyurethane elastomer based on special wear-resistance and good mechanical properties, from the 1960s were the beginning of polyurethane elastomer tire in the study. Especially in the years 1974-1975, U.S. Air Force flight power laboratory with Zedron companies pouring on the tire tread casting and live in the United States Air Force aircraft tires used on the feasibility study. It has been revealed that the possibility of using the material is thermoplastic polyurethane elastomer (DuPont manufacturing, goods, called Hytrel), carcass and bead no reinforcement material. Dynamic test: 6.00-6 in the pouring tires, low profile tires pouring 15 × 6.00-6 and 6.00-6 of living, such as tire tread casting 3 tire test, the latter to obtain better results, including a child successfully test Through 89 times taxiway the pilot to take off. Test conditions are: 1 mile taxiway (1150 lb load, speed of 30 miles per hour), the speed from 0 miles per hour to 90 miles off the findings of the study: the development of casting live or tire tread aircraft (with up Strong reinforcement material) pouring aircraft tire is feasible. 1977-1979 Zedron contracting company in the United States and the flight of a driving force for laboratory research and development contract to study the 7.00 × 8 / 16 level A-37 aircraft pouring the feasibility of tires. Tire design load for 6650 pounds, 125 pounds for the air pressure -2 inch, the use of the speed of 150 miles per hour. Test concluded that: the modification of thermoplastic polyurethane elastomer (trade name Hytrel) have the best dynamic performance in the rated load successfully the taxiway 3 miles, the highest burst pressure of 400 pounds inch -2; the study Using the test materials, specially designed to basically be able to cast the tire to provide sufficient size of the static stability of the vertical and lateral rigidity, the lagging performance of friction. However, the area of prints, brake, come back to the lack of torque; blasting test, dynamic test still fail. Polyurethane elastomer on the Young's modulus is not only a kind of plastic with a high hardness, high elastic rubber with the polymer composite materials, including polyurethane rubber, plastic cast polyurethane, latex and polyurethane water thermal plastic polyurethane . Polyurethane elastomer and rubber, compared with more excellent wear resistance, high tear strength and elongation and hardness range. In addition to its vibration absorber, the damping effect is good, weight-bearing capacity is very large and the very ideals of the oil and other chemical-resistant properties. As the polyurethane elastomer with other polymer does not have special physical and mechanical properties, so their defense, textile, transport, oil, mining, machinery, construction, medical and many other aspects of a wide range of applications, but also to create high-performance tires The ideal material. In particular, cast polyurethane elastomer is the most flexible of the wear-resistant, high wear-resistant, can be colored, high cutting resistance, oil resistance and excellent chemical resistance, etc., and non-toxic to humans, but also completely bio - Degradation, but also do not have to add carbon black and aromatic oil, tire tread is to create an ideal material.

Polyurethane casting process used tires, and its current structure and the production of tires is very different. Polyurethane all-inflated tire carcass is, the belt and tread 3 parts. Matrix from which the high modulus polyurethane elastomer by casting relatively hard (Shore-A hardness of about 85-95 degrees), so fatigue-resistant properties, dimensional stability and resistance to cutting than better performance; matrix The upper part of the belt along the winding week to the Kevlar or steel cord constitute, by the tread of low modulus polyurethane elastomer (Shore-A hardness of about 70-75 degrees) by pouring in order to ensure that the tires Driving performance and wear resistance.

Research and development in the entire polyurethane tires inflated at the same time, research and development is also a part of the polyurethane tires inflated. Polyurethane part of the pneumatic tire in two forms: One is the matrix for the casting of polyurethane, and the tread is used in the manufacture of ordinary rubber tires: the other is the matrix for the radial matrix, and the tread is polyurethane. The former is less costly, and the traction better than polyurethane for the tire tread. The latter in turn fetal industry more attention.

Polyurethane tires inflated with ordinary steel radial tire, compared with the following advantages: (1) Average fuel consumption 10%; (2) tread wear low 51%; (3) light weight, 30%; (4) low rolling resistance More than 35%. In addition, the manipulation of polyurethane tire performance and road performance with similar tire, brake performance is just over 6% lower radial tire, radial tire cornering than 7%. I cut anti-growth, in accordance with the provisions of the German TUV test method, in the sidewall of 3cm incision cut mouth, and then 150% rated load and speed of 75km per hour carried out under the driving test, running 3000km after I did not find cut growth All this shows the cut is well-positioned to sweep the anti-growth. In addition, the polyurethane rubber tires than the tires better uniformity, and will not tread off the phenomenon.

Polyurethane tires currently the main problems in the current study of polyurethane tires are still some problems to be solved, that is, polyurethane tires to increase traction braking performance, water-resistant solution to improve performance and truck tires on many occasions, such as injection molding process. In the development of polyurethane tires, high temperature performance is the practical impact of polyurethane tires of the main factors. In the emergency brake, the tread due to the accumulation of heat caused by rapid warming, causing the tire in the process of braking performance of the rapid decline (100 ℃ under the wear and tear strength at room temperature only about 20%). Measures to tackle the problem of raw materials to improve in the course of the study found that the nitrogen-based polyurethane ester-based high temperature is the main reason for poor performance, and now abroad, developed by the three-isocyanate obtained the raw material for polyurethane Elastomer very good performance of high temperature, normally 170 ℃ heat-resistant up to 210 ℃, and other mechanical properties such as tear strength, wear resistance, have increased, so the high temperature properties of polyurethane has been basically To solve.

Amy is a Lété was founded in 1995, the technology development company in the development of polyurethane tires made many efforts and achieved gratifying results. Recently, Amy Levin has developed a special polyurethane material, the material from the polyol, diphenylmethane diisocyanate, and other components. Goodyear's use of such materials trial of a new generation of polyurethane tires. After tests proved that the new product safety, uniformity and wear resistance than rubber tires, but not easy to produce and spin-off tire tread. According to Goodyear, said the real achievement of polyurethane tires of commercial production may take several years of efforts, but through sustained research and development, the prospect of polyurethane tires is good.

Manufacturing Process Improvement

Luo Yier unilever solid Goodrich Corporation has developed a new type of tire production technology, design principle and is about to cast polyurethane material characteristics of the combination. Using the technology of the production of tires, all performance parameters can be used to meet the requirements, there is a very good prospect of application. This tire has a flexible matrix, the matrix above, there can be tread, the carcass under pressure in the installation of metal or wheel rim, a non-inflated tires. Non-pneumatic tire has many advantages, such as the tire is solid, not sealed or compressed air, thus the existence pneumatic tires did not run the gas issue will not arise as a result of a large number of heat problems arising from sponges, in addition, non-rechargeable Gas is a polyurethane tires will not happen without serious damage to repair the system. Non-inflated tires can be a reasonable use of materials, parts and rubber to reduce the load off area, to reduce costs and at the same time because only a single assembly can be removed from various parts of the assembly work. Manufacture of non-pneumatic tire carcass material must be a good performance elastomer, and it must match the design, even though more than 500% of the deformation can be ELASTOMER return to the status quo. Polyurethane casting is the only design and materials needed to meet the rigid requirements of the existing material.

Rubber tire tread have to add carbon black and carcinogenic effects of the aromatic oil, as they tread wear and released into the air, seriously pollute the environment. South China University of Technology and the Guangzhou Science and Technology Co., Ltd. Chinese laborers rivers controlled study to master the renovation of polyurethane tires of the key technologies to make polyurethane tread commercial applications become a reality. The key technology uses nanotechnology to improve polyurethane elastomer thermal stability so that the maximum temperature reached 120 ℃, Hill developed low-cost and easy to use and effective rubber surface treatment agents and adhesives, polyurethane so that the tread rubber and ordinary can Firmly bonded together. Using polyurethane tread than the actual mileage tire general 1-2 times higher, at the same time eliminate a lot of carbon black and aromatic oil pollution on the environment, the renovation is to improve the performance of fetal new ways.

Polyurethane renovation of the superiority of the child are: (1) of the tread material does not contain the poisoning effect of the oil-filled; (2) does not contain carbon black, tread wear can keep the environment clean; (3) be able to fully biodegradable and will not lead to Environmental pollution; (4) low rolling resistance, vehicle fuel consumption can be saved; (5) ordinary natural rubber tires, has an excellent solvent oil, oil resistant and chemical resistant properties, is the oil depots, terminals and other special vehicles An ideal choice for tires. South China University of Technology has successfully developed a set of radial tires and cast polyurethane tires on the merits of a new "green tire", which is a radial matrix and the composition of a new type of polyurethane tread compound tires. It has a small radial tire rolling resistance, safety, comfort the advantages of high, but also has high wear resistance of polyurethane elastomer, and other advantages of flexible polyurethane and overcome the body's shortcomings high heat. At the same time during the manufacturing process does not add carbon black and carcinogenic effects of the aromatic oil; compared with the traditional tire, highlights the new technology, new materials, environmental protection, energy saving, and many other advantages. Shanghai, Ningbo, Zhejiang, and other units to be built in 2007 with an annual output of 3,000,000 of such new type of car tires, 1,000,000 new truck tire production line, the tire industry at home and abroad will elastomer development of far-reaching impact.

The future development trend

The automotive industry developed into a high-speed tires to improve the structure of the direct driving force, and the development of automobile tires, the car is also necessary to improve the performance of one of the conditions. The tire tread wear a direct impact on the life of the tire, and the wear is directly related to the tire economy. It is clear that the wear resistance, rolling resistance and slip resistance (or of clinging) is the tire maker for the auto industry's emphasis on performance. With the continuous improvement in the performance of automobile tires and increasing the use of harsh conditions and require tire manufacturers to keep to the use of new materials, to change the structure of the tire, the tire to live longer, safe and environmentally friendly direction.

At present, the use of rubber tires in the production and use of the process will have a lot of waste, scrap tires after the recycling is very difficult to easily give rise to environmental pollution. Every year millions of scrap tires waiting to deal with, and deal with these tires also spends a great deal of human, material and financial resources. Due to the wear resistance of polyurethane tires, rolling resistance, as well as tear and so much better than both radial tire, the same size of polyurethane rubber tire is a tire load capacity of 6-7 times its production process can be automated and continuous, In the course of the production and use of waste produced little, but more important is that the waste tire recycling part of the carcass can be used in the manufacture of other polyurethane products, will not cause environmental pollution, and its simple manufacturing process - pouring liquid molding, belonging to the No pouring a new tire cord, which people call in the 21st century green tire.

There is no doubt that environment-friendly tire in the 21st century will be the hot tire research and development, will be the mainstream of the development of automobile tires in the automotive industry has a broad application prospects. The industry believes that with the polyurethane material as well as the performance of polyurethane tires to improve the production technology, large-scale production of polyurethane tires in the near future will become a reality. Polyurethane tires to replace the tire rubber is the world's tire industry in the future development direction.