HNBR and the application of research

I, HNBR Application

With the automobile, oil industry, rubber components in addition to oil requirements, the need to have good heat resistance, high temperature, high pressure, oxygen-resistant properties, and so on. General NBR (NBR) has been far from meeting these requirements, although some of these uses have been replaced by fluorine rubber, but the high cost of fluorine rubber. Therefore, people began to seek to improve the performance of the NBR, HNBR is to meet the needs of this new development a success.

HNBR for the high temperature of 130 ~ 180 ℃, for cold resistance -55 ~ -38 ℃ and good mechanical properties, compared with other polymers to better meet the requirements of the automobile industry. Using ZnO / methacrylic acid (MAA) reinforcement of the HN BR can be produced Triangle, Triangle, and other regulations, with more than 30 cents of the bottom plastic ring, isolation, etc.; ring can be prepared, seals, heat pipes and so on. In the oil drilling, require high-temperature resistant rubber products, high-pressure, acid, amine, H2S, CO2, CH4, such as steam test. HNBR prepared using a variety of products, acid, oil, solvent. Using ZnO / MAA reinforcement of HNBR can be used for the production of drilling mud used to protect me and the Pistons. In addition, the method used to beating HNBR made of paper-washer can be used as the oil industry and automobile sealing gasket. HNBR heat, radiation-resistant than the performance of silicone rubber, fluorine rubber, polyethylene PCE better, suitable for power stations of all kinds of rubber seals, used for hydraulic pipes, hydraulic seal, with power cable sheath, Can also be printed and fabric roller, weapons and aerospace components with seals, cover, such as fuel capsule; HNBR latex can be used as surface coating (painting), textiles, paper, leather, metal, ceramics, non-woven fiber The adhesives, as well as foam rubber, latex impregnated products. In addition, the use of ZnO / MAA, peroxide, high wear-resistant reinforcement of the furnace and HNBR, their performance is better than HNBR.

Second, HNBR Preparation

Preparation HNBR There are three main methods: a Ethylene Act acrylonitrile copolymer, NBR hydrogenation solution and latex NBR hydrogenation method. Acrylonitrile-ethylene copolymer prepared HNBR, as a result of the reaction copolymerization monomer different reaction rate (rAN = 0.04, rE = 0.8), compared with refractory, and the polymer line performance is not too good, this law Small is still in the research phase of the trial.

Hydrogenation of NBR latex is the use of methyl hydrazine sulfonyl thermal decomposition have been N-II, it is an effective reducing agent hydrogenation, in 1984 by the WideMan published for the first time using N-reducing agent for the preparation of emulsion HN BR process, he NBR latex can be found in hydrazine hydrate, oxidants such as oxygen or hydrogen peroxide, as well as copper, iron and other metal ions initiator of a direct role in the next generation of HNBR. U.S. GoodYear rubber tire companies such as Parker used latex hydrogenation of the legal system had HNBR latex, the formula for the (quality of the copies): NBR latex: 100g, CuSO4 5H2O: 0.008g, sodium lauryl sulfate: 0.15g, defoamer, Hydrazine hydrate: 15.6g, H2O2: 16.66g. Reactor in Canada who NBR latex, CuSO4 5H2O, surfactant, heated to 45 ~ 50 ℃, adding hydrazine hydrate, and then later added 7h End H2O2, and add defoamer, the mixing temperature 1 hour available HNBR . As the mother hydride (p-toluenesulfonyl hydrazine) is expensive, slow rate of hydrogenation, the law is still in the phase of the trial small.

NBR hydrogenation of the solution is in the NBR solution to the precious metal palladium, calcium, rhodium catalyst for the use of hydrogen for hydrogenation. NBR molecular chain of propylene eye determines the content of its oil, hydrogenated NBR, the only unit of the diene double bond hydrogenation selective restore capacity key is not hydrogenated acrylonitrile unit of eye-side chain-C ≡ N. The current selection of the two main law hydrotreating catalyst, that is, heterogeneous catalyst carrier and coordination are the catalyst. First of all, come out of the heterogeneous catalyst carrier based on carbon as the carrier of the Pd / C catalyst, the catalyst of high selectivity, hydrogenation rate up to 95.6 percent, but in the hydrogenation reaction, carbon black and affinity of the diene rubber E-absorption in the surface of carbon black, carbon black easily when stirred together into a block, found in HNBR, its curing properties will have a negative impact. Japan's Zeon SiO2 as the carrier of choice Pd/SiO2 catalyst has been achieved industrialization. The two catalyst hydrogenation carrier NBR time, NBR catalyst residues or polymerization additives may be used in the adhesion to the surface or remain in the porous, so that the catalyst for a sharp drop in activity, the impact of re-use.

Coordination catalysts are currently three common: palladium catalyst, a catalyst rhodium and iridium catalyst, palladium catalyst on the water and air stable, easy storage and transportation, recycling can be repeated, but poor activity and selectivity; iridium catalyst with hydrogenated NBR Very high activity and selectivity, has become one of the hot spots of the development of HNBR. Rhodium catalyst with the highest activity and selectivity, RhH (PPh3) 3-hydride rhodium catalyst in solution or emulsion of NBR to carry out hydrogenation reaction used as a solvent benzene, a temperature of 80 ~ 160 ℃, hydrogen pressure 0.05 ~ 3MPa, from 2 to 10 hours. In order for the stability of the catalyst needed to join PPh3, catalyst and the amount of PPh3 were 0.05% ~ 20%, l% ~ 25% (to the base for the NBR), the two mass ratio of 0.6 / 1 20 / 1. The catalyst system of high activity and selectivity for the hydrogenation rate of the minimum 95%. However, rhodium strain on the resources, high value, large-scale production should be recycling, Yongsan-Silane was absorbed HNBR in the residual 81% rhodium.

Third, the conclusions

HNBR in the NBR to maintain the existing excellent oil resistance, was given a very good heat resistance (heat resistant to 150 ℃), ozone-resistant, and its use in the field have broken through the traditional areas of the NBR, making CPE , CSM, and other special rubber has also dealt a blow. From an economic point of view, HNBR sales price for the time being is also more expensive, but still much lower than the fluorine rubber. At the same time, as a result of the HNBR stiffness low technology performance, low-density, we can get more people packing, and HNBR products unit volume is only half of fluorine rubber, so that it will become a special fluorine rubber, elastomers substitutes. Although, HNBR production abroad has been for many years, its use has been expanding in mainland China is still blank, we should lose no time in the development of HNBR. As far as I understand, China's Daqing, Shengli Oilfield has more than 2,000 Phase I required submersible pump in the well depth of 2,000 meters, the temperature around 140 ℃ under pumping, such as the use of NBR spindle, the life cycle of only a few months or even shorter, HNBR such as the spindle, the life cycle of up to more than one year. China's Nanjing plant a rubber each year on the need to HNBR30 tons. HNBR in the manufacturing, NBR catalytic hydrogenation technology is the key to the solution of NBR hydrogenation production technology harsh conditions, the Portland-based company has been conducting this research, because of the low recovery rate of rhodium, the cost is relatively high. In recent years, the two-phase water-soluble catalyst for hydrogenation and formylation hydrogenation Study is aimed at separating the precious metal catalyst recovery and recycling, if this type of catalyst can be extended to the application of polymer hydrogenation, will be able to They used to carry out the NBR hydrogenation, at present, we have synthesized the two water-soluble phosphine ligand, being tried in this area.