At the end of 2021, the Ministry of Industry and Information Technology of China issued the "Catalogue of Demonstration Guidance for the First Batch of Key New Materials (2021 Edition)", which will be implemented from January 1, 2022. Among them, under the category of advanced chemical materials, special rubber and other polymer materials, hydrogenated nitrile rubber (HNBR) products are added. HNBR is a highly saturated special elastomer obtained by hydrotreating nitrile rubber (NBR). Compared with NBR, HNBR molecular structure contains a small amount or no carbon double bond, while maintaining NBR oil resistance, wear resistance and other properties, but also has more excellent heat resistance, oxidation resistance, ozone resistance, radiation resistance, chemical resistance and other properties, is a kind of special rubber with excellent comprehensive performance.
First, the domestic HNBR market is still in its infancy
In 2021, the domestic HNBR production capacity is 5000 tons / year, and there are two main production enterprises, namely Zhejiang Zansheng New Material Co., Ltd. and Shandong Dawn Special Elastomer Material Co., Ltd. Zhejiang Zansheng has a production capacity of 2,000 tons / year, put into operation in 2015; Shandong Dao'en production capacity of 3,000 tons / year, put into operation in 2019, there is no other enterprises to build new expansion information. In 2021, the total output of the two domestic enterprises is about 2,000 tons, and the overall operating rate is only 40%.
Foreign production enterprises are mainly Germany LANXESS and Japan Ruion, of which the total production capacity of Germany LANXESS is 10,000 tons / year, divided into two factories to produce HNBR, one in Leverkusen, Germany, and the other in Texas, USA; the total production capacity of Japan Ruion is 9,500 tons / year, divided into three factories to produce HNBR, two are located in Takaoka City and Kawasaki City, Japan, and the other is located in Texas, USA. In 2021, the total import of HNBR from the above two enterprises in China is about 1,000 tons, and domestic enterprises have almost no exports.
Table 1 The main manufacturers of hydrogenated nitrile oak in the world in 2021
In 2021, China's HNBR consumption will be about 3,000 tons, mainly for the production of sealing gaskets and timing belts and other products. Among them, the sealing gasket industry consumes about 2100 tons, not only for the automotive industry, but also for oilfield exploitation and aerospace and other fields. At present, the mainstream brands in the market are ZN35156, ZN35158, ZN35256, ZN35258, Zetpol 1020, 2010, 2020 and LANXESS's Therpan A3406, A3907, B3629, etc.; the synchronous belt industry consumes about 700 tons, mainly for the automotive industry, and the current mainstream brand in the market is ZN35153, Reun's Zetpol 2020L, LANXESS' Therban C3446。
Figure 1 Consumption structure of hydrogenated nitrile rubber downstream products in 2021
From the perspective of terminal downstream, HNBR products are mainly used in automobile manufacturing, oilfield exploitation and aerospace and other fields. Among them, the automobile manufacturing industry is the largest terminal field, HNBR demand in 2021 is about 1700 tons, accounting for 56.7%, widely used in automotive transmission system oil seals, fuel injection system seals, timing belts and steering tubing, etc.; followed by the oilfield exploitation industry, HNBR demand in 2021 is about 900 tons, accounting for 30.0%. Rubber products in the oilfield industry need to have higher oil resistance, while withstanding the physical and chemical damage of drilled mud and other corrosive substances, HNBR can meet the required requirements, can be used to make packer cartridges, screw pump stators and blowout preventers, etc.; the aerospace industry accounts for 4.0%, 2021 HNBR demand is about 120 tons, mainly for aerospace seals; other industries mainly include military industry, air conditioning, printing field accounted for 9.3%, In 2021, HNBR demands about 280 tons, mainly for tank track liners, various rubber seals for the nuclear industry, air conditioning sealing products, printing and textile rubber rollers, etc.
Figure 2 Consumption structure of hydrogenated nitrile rubber terminal field in 2021
At present, the overall size of the HNBR market is small, and it is expected that there will be no significant increase in both the supply and demand ends by 2025, and the current scale will still be maintained. As the growth rate of the automobile manufacturing industry slows down, the growth rate of demand for HNBR will be reduced in the future. Due to the continuous deepening of China's oilfield development, HNBR-related products have received more attention and application, so the growth rate of HNBR demand in the oilfield development industry will accelerate. In general, the field of automobile manufacturing and oilfield development will continue to be the main application terminal of China HNBR, and as a national strategic material, the new demand growth point will come from the aerospace and military industries. Although the domestic HNBR has achieved large-scale production, but the product quality can not meet the needs of specific areas, in the face of the high price of foreign products, the domestic large-scale application development, still need a certain period of time.
Second, HNBR has good substitution
(1) HNBR and nitrile rubber
When the actual application of NBR exceeds 120 °C, the double bond on the main chain, that is, the butadiene chain, is attacked by oxygen, and the broken key occurs, so that the NBR loses its high elastic energy and application function prematurely. Compared with NBR, HNBR has better heat resistance, higher tensile strength, and low temperature resistance can reach -50 °C. For example, in the application of auto parts products, the use temperature of conventional NBR is 100 °C, and the special formula of NBR can be used at 150 °C, but for a long time in the high temperature environment of acid gasoline and 150 °C, its ozone resistance and radiation resistance are poor, and it has not been able to meet the sealing requirements of the vehicle for the engine, and the conventional use temperature of HNBR can reach 150 °C, and the tensile strength and aging resistance are more excellent, so the gearbox seal produced by NBR is used in the past. Shock absorber oil seals and power steering oil seals are gradually switching to HNBR.
(2) HNBR and fluoroelastomer
Due to the needs of environmental protection, automotive fuel often contains a variety of additives, such as methanol, ethanol, methyl tert-butyl ether, amine corrosion inhibitor, anti-wear agent, etc., thus putting forward higher requirements for rubber parts in contact with fuel. Both HNBR and Fluoroelastomer have excellent fuel oil resistance, corrosion resistance and low media transmittance. Compared with fluoroelastomers, HNBR has higher tensile strength, better chemical resistance to media and stronger cold resistance. For example, in the field of automobile manufacturing seals and other product applications, rubber products are required to maintain normal function in the temperature range of -40 °C ~ 150 °C, fluoroelastomer can work for a long time at 200 ~ 250 °C, but the low temperature resistance of fluoroelastomer deteriorates with the increase of fluorine content, and the low temperature resistance of HNBR can reach -50 °C, high temperature resistance of 150 °C, which can meet the above requirements, and when the HNBR grade with acrylonitrile content of about 43% is elected, It can achieve a good balance between fuel oil resistance and low temperature resistance, and the comprehensive performance is better than that of fluoroelastomer.
(3) HNBR with neoprene
Neoprene has the same good oil resistance and high physical and mechanical properties as HNBR, but when used to manufacture timing belts for rubber parts in dynamic stress situations, HNBR has obvious advantages, especially when the use temperature is higher and the continuous use time is longer. Under the action of dynamic stress, after a long period of high temperature aging, HNBR still has high physical and mechanical properties, dynamic permanent deformation is small, elongation and hardness change is small, and under the same conditions, neoprene is often destroyed and loses its use value. For example, in the application of automotive timing belt products, the automotive timing belt originally used neoprene rubber with good comprehensive performance, but with the continuous development of the automotive industry, the speed and power of the automobile engine continue to increase, and the heat resistance requirements of the timing belt product exceed 120 °C, and the neoprene timing belt is difficult to meet the requirements under this condition. HNBR has better high temperature resistance, and can improve the service life of the timing belt under high temperature and dynamic conditions, so the rubber for the timing belt is gradually developed from neoprene rubber to HNBR.
Iii. Constraints on the current development of HNBR
(1) Technical threshold
Foreign Germany LANXESS and Japan's Ruion began HNBR's independent research and development work as early as the 70s and 80s of the last century, and successfully launched products after the 1980s. As early as 1990 in China, the Beijing University of Chemical Technology joint venture did relevant research work, in 2015 Zhejiang Zansheng New Materials Co., Ltd. relied on its parent company Zannan Technology (Shanghai) Co., Ltd. to develop the Zhan's catalyst and catalytic hydrogenation technology patent to successfully produce HNBR, and Shandong Dawn Special Elastomer Materials Co., Ltd. is jointly developed with Beijing University of Chemical Technology, breaking down technical barriers, in 2019 put into production HNBR production plant with completely independent intellectual property rights. From the perspective of investment scale, the plant investment amount of Zhejiang Zansheng and Shandong Daoen is close to 50 million yuan / thousand tons, the synthesis process of HNBR is complex and not easy to control, solvent consumption is large, and catalyst purification is difficult, resulting in its market price is very high, almost several times or even more than ten times of traditional rubber, and the catalyst accounts for up to 85% of the cost of HNBR. On the whole, the technical threshold of the HNBR industry is mainly the difficulty of independent research and development of production technology or technology introduction, especially as the catalyst formula of core technology, and requires technical support from industry experts in terms of device construction, trial operation, industrial stable production and customer service.
(2) Application barriers
The main terminals of HNBR products are automobile manufacturing, oilfield exploitation, aerospace and military industry. In the field of automobile manufacturing, German and Japanese auto parts manufacturers can only use HNBR products of LANXESS of Germany and Ruiweng of Japan due to contract provisions or product quality requirements, and domestic HNBR products are difficult to enter. In the aerospace and military industries, due to the higher requirements of special industries for the performance indicators and stability of HNBR, it is necessary to sell new HNBR products in the civilian market for a period of time before they can obtain the qualifications to enter the above industries, and the entry threshold is relatively high. At the same time, HNBR as a high-performance special rubber, the price is much higher than the ordinary special rubber, in many application areas considering the economy, not necessarily completely using HNBR, only in the case specified by the customer will be used, so the production of HNBR mainly depends on the needs of downstream customers, generally according to the order production.