On September 22, at the “2016 International Graphene Innovation Conference” and “2016 International Advanced Carbon Materials Exposition”, Qingdao Sentury Tire Ltd. and Qingdao Huagao Graphene Technology Corp. Ltd. jointly held the “Sentury-Huagao Graphene First Graphene Conducting Electrostatic Tire Release Conference” and announced that the graphene conducting electrostatic tire broke “The Devil’s Triangle” law in the field of tire formula, successfully making really property-balanced high-performance tires with high abrasion, high wet skid resistance and low-rolling resistance. In the meanwhile, it also marks the first industrialization of graphene materials in the tire industry, which will create a new technology revolution reform in the global tire industry.
Performance Improved Comprehensively Compared with Traditional Tires
In October 2015, the Graphene Conducting Electrostatic Tire LANDSAIL 245/45ZR18 100W LS588 SMX jointly researched and developed by Qingdao Sentury and Huagao Graphene completed the trail manufacture for graphene conducting electrostatic tires, in which Huagao Graphene developed and provided the Huaguang 2# modified graphene materials especially used for tires, and Qingdao Sentury mixed graphene materials into such components as tread, side wall and apex with the use of the rubber compound modified prepara- tion technology. The first graphene conducting electrostatic tire was successfully put into production and came off the assembling line on September 14, 2016.
Li Zhongdong, the chief engineer of Sentury Tire Ltd., introduced that exfoliated from graphite material, graphene is a kind of two-dimensional crystal composed
of carbon atoms with one layer of atoms in thickness. Known as “black gold” and “the king of new materials”, it is a new nano material with the thinnest structure, the hardest strength and the strongest conductivity and thermal conductivity so far discovered. With outstanding mechanical property and heat dissipation performance, its strength of extension reaches 125GPa and thermal conductivity is 5300W/m.k under normal temperature, which is 12 times higher than copper. Thus, the heat dissipation performance and mechanical strength of the graphene conducting electrostatic tires also have an outstanding performance. With a significantly increased travel mileage, their tensile strength, tearing strength, modulus, DIN abrasion, rolling resistance and wet skid resistance are much better than those of common tires.
It is known that because graphene is difficult to disperse evenly, rubber materials with mixture of graphene are hard to process. Sentury Tire Ltd. adopted the variable clearance mixture technology (VCMT), using the shear ladders distributed on long and short edges of the rotor to assist shear isolation ladders and scattered ladders with uninterrupted cyclic change around and around during the rotation of long and short edges in axial and radial directions, so as to reach the utmost shear, dispersion, tete-beche and optimum temperature as well as guarantee the homodisperse in rubber materials of graphene which is hard to be mixed.
After the test of the third party authoritative testing organization certified by the national CNAS accredited laboratory and Germany TUV——Anhui Deji Automobile Inspection Center, it turns out that the electrical conductivity of the graphene-based tires is improved by over 4 orders of magnitudes than common tires, reaching 10-5 s/m. With tires embedded in metal wheel hubs, the static conductive tread is connected with the ground, thus static electricity is conducted from the car body all the time, continuously and reliably. The high reinforcement of tread produced by graphene increases rubber modulus and tensile strength by 50%, improving the tear resistance performance of tires, so that the tire performance on road and cross-country could be brought into full play. The wetland braking length is shortened by 1.8m and wet skid resistance is improved by 6%, thus tire safety is further enhanced. The heat-conducting property is improved by about one time compared with that of the traditional rubber materials and the time of tire vulcanization is further shortened, reducing the tire burst rate. The tire mileage is increased by 1.5 to 1.8 times, breaking “The Devil’s Triangle” law in the field of tire formula, realizing performance balance on high abrasion, high wet skid resistance and low rolling resist- ance. The weight of tires is reduced by 10% in favor of reducing the weight and the rolling resistance of tires effectively.
Why Should Tires Conduct the Static Electricity?
Scientific research shows that static electricity may cause abnormal current conduction of brain nerve cell membrane, affect the central nervous and cause symptoms like dizziness, headache, dysphoria, insomnia, inappetence, restlessness, mental trance. In serious cases, it may affect the human metabolism, leading to blood glucose rising, skin diseases, neurological disorders, immunity declining, etc.
Shi Jianxin, the president of Qingdao Huagao Graphene Technology Corp. Ltd. introduced that vehicle static electricity may cause temporary amnesia, blood pressure rising or arrhythmia, especially soar or arrest of heart rate for patients with cardiac pacemakers. It may also interfere with the normal operation of electronic equipment in the car, making the equipment working unstably and damaging the electrical components in the car especially those with complex integrated circuits and microelectronic components. Besides, fire and explosion may also be caused by static electricity. In particular, it may cause disastrous consequences to flammable and explosive transport vehicles. However, with outstanding conductivity, graphene provides a possibility for cars to conduct static electricity reliably, which makes electron transfer barely be influenced by temperature. Graphene tires could replace the existing anti-static belts or anti-static iron chains in the cars.
Li Zhongdong indicated that the key function of the graphene conducting electrostatic tire is that it replaces extra mobile units for conducting static electricity, so that there are no potential security problems, effectively avoiding drivers and crew from electrostatic damages as well as vehicle fire and explosion.
With outstanding generalization performance, the preparative technology of graphene conducting electro- static tires doesn’t need to modify the original tire pro- duction equipment and production lines with large-scale technical transformation but make graphene compound modification in the preparation formula of various categories (models) of tires with their former appearance, size, weight and dynamic performance unchanged.
The Application Prospect of Graphene Tires Can Be Expected
The graphene conducting electrostatic tires can conduct vehicle static electricity efficiently, avoiding vehicle fire and explosion. Besides common vehicles, they especially suit for flammable and explosive transport vehicles, special vehicles for electronic equipment, special military (police) vehicles and other vehicles with special needs.
As introduced by Xing Yuepeng, the senior ex-ecutive manager of Tianjin Hi-tech New Energy Auto Research Institute Co., Ltd., new energy electromobiles don’t use AC generators, so it is easy to generate static electricity inside the car. The current research has not totally solved this problem, while the graphene conducting electrostatic tires provides an effective solution.
Currently, many enterprises are carrying out their research on graphene tires. This year, Doublestar Global R&D Center & Graphene Tire Central Lab laid a foun- dation in the West Coast of Qingdao New District on March 18. The project covers an area of about 120 mu, with the building are of 160,000 square meters and a total investment of RMB 1 Billion Yuan, aiming to build up a platform for research and development, inspection and certification of high-performance tires as well as a global advanced graphene tire central lab, thus realizing the industrialization of high-end graphene tires.
Lanwan ENE-Carbon (Qingdao) Materials Technology Co., Ltd. also attended the International Advanced Carbon Materials Exposition. It is learnt by the reporter that they were carrying out their research and development on graphene/rubber and plastic master batch, whose products can be applied on tires, base plates, oil seals, rubber covered rollers, conveyer belts, latex products, anti-vibration products, etc.
It is known that the graphene electrostatic tire project jointly developed by Qingdao Sentury Tire Ltd. and Qingdao Huagao Graphene Technology Corp. Ltd. will complete batch trial manufacture in this year. In the first five-year plan of the first stage, the annual production capacity is 5 million units, which will be completed in 2022; in the second five-year plan of the second stage, the annual production capacity is 10 million units, which will be completed in 2027.
What’s more, it is also known that the biggest problem at present is the high price of graphene and the high requirements of extraction process. Li Zhongdong told the reporter that the cost input in graphene tires invested by Sentury would increase by 20%~30%, but the overall improvement of comprehensive property would make the performance of graphene tires exceed that of international brand tires. Currently, there is a big difference in the market price between Chinese tires and international brand tires. Thus, graphene tires are still highly cost effective.
