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文中介绍了防焦烧型过氧化物和液体活性剂在氢化丁腈橡胶中的应用。经过实验发现,防焦烧型过氧化物能增加胶料的焦烧安全性、同时对胶料的物理性能无不利影响,加入活性剂可降低胶料的黏度,改善胶料的流动性以及压缩永久变形性能。 相似文献
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Chandra Mouli R. Madhuranthakam Qinmin Pan Garry L. Rempel 《American Institute of Chemical Engineers》2009,55(11):2934-2944
A continuous process for hydrogenating nitrile butadiene rubber (NBR) was developed and its performance was experimentally investigated. A Kenics® KMX static mixer (SM) is used in the process as a gas–liquid reactor in which gaseous hydrogen reacts with NBR in an organic solution catalyzed by an organometallic complex such as an osmium complex catalyst. The Kenics® KMX SM was designed with 24 mixing elements with 3.81 cm diameter and arranged such that the angle between two neighboring elements is 90°. The internal structure of each element is open blade with the blades being convexly curved. The dimensions of the SM reactor are: 3.81 cm ID 80 S and 123 cm length and was operated cocurrently with vertical upflow. The NBR solutions of different concentrations (0.418 and 0.837 mol/L with respect to [C?C]) were hydrogenated by using different concentrations of the osmium catalyst solution at various residence times. The reactions were conducted at a constant temperature of 138°C and at a constant pressure of 3.5 MPa. From the experimental results, it is observed that a conversion and/or degree of hydrogenation above 95% was achieved in a single pass from the designed continuous process. This is the first continuous process for HNBR production that gives conversions above 95% till date. Optimum catalyst concentration for a given mean residence time to achieve conversions above 95% were obtained. Finally, a mechanistic model for the SM reactor performance with respect to hydrogenation of NBR was proposed and validated with the obtained experimental results. © 2009 American Institute of Chemical Engineers AIChE J, 2009 相似文献
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The influence of the curing temperature on micro‐nano structure transform of hydrogenated nitrile‐butadiene rubber (HNBR) reinforced by zinc dimethacrylate (ZDMA) through in situ polymerization was studied by means of Scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, and X‐ray diffraction. The results showed that both the amount and diameter of the poly‐ZDMA aggregates increased and the graft ratio of poly‐ZDMA decreased with the increase of curing temperature. Meanwhile, with the increase of curing temperature, the maximum torque of the curing curve, the crosslinking density (especially for the ionic crosslinking density), and the mechanical properties of HNBR/ZDMA composite decreased significantly. We put forward a possible mechanism that can well explain the phenomenon observed in this work. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 相似文献
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The vulcanization properties, mechanical properties of hydrogenated nitrile rubber (HNBR) filled with carbon black (N550), zinc dimethacrylate (ZDMA), SiO2 independently and two of three kinds of fillers together were investigated, respectively. The filler‐dispersion was characterized by the transmission electron microscopy (TEM) and dynamic mechanical properties. The results showed that HNBR composite filled with SiO2 or ZDMA displayed high tensile strength, elongation at break and compression set. The HNBR composite filled with N550 displayed low compression set, tensile strength and elongation at break. The dispersion of SiO2 in HNBR compound was better than that in HNBR vulcanizates because of SiO2 particles self‐aggregation in vulcanizing processing. ZDMA particles with micron rod‐like and silky shape in HNBR compounds changed into near‐spherical poly‐ZDMA particles with nano size in HNBR vulcanizates by in situ polymerization reaction. The N550 particles morphology exhibited no much change between HNBR compounds and vulcanizates. N550/ZDMA have the most effective reinforcement to HNBR and the appropriate amount of ZDMA is about 25% of total filler amount by weights. The theory prediction for Payne effect (dispersion of the filler) shown by the dynamic properties is identical with actual state observed by TEM. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 相似文献
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研究了不同交联助剂的过氧化物硫化体系对氢化丁腈橡胶(HNBR)胶料性能的影响,以及填充补强剂对制品使用寿命的影响。结果表明,尽管过氧化物硫化体系的HNBR胶料耐热空气与油老化性能均较好,但只有同时加入有机金属盐与1,2聚丁二烯2种交联助剂才能获得最理想的性能;补强剂以半补强炭黑N774可以使胶料获得最佳的综合性能;填充一定量的固体润滑剂可以进一步提高产品的使用寿命。 相似文献
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The effects of electron‐beam irradiation on morphology, mechanical properties and on the heat and hot oil resistance of the thermoplastic elastomeric blend of 30:70 and 70:30, nylon 6 and hydrogenated nitrile rubber (HNBR) were investigated over the dose range 0–8 Mrad. The insoluble content of blends increased with increase in the radiation dose. The morphology of the blend was studied in scanning electron microscopy, with special reference to the effect of radiation prior to processing via injection molding. Irradiated pellets showed better mechanical properties after injection molding compared with irradiated sheets at low radiation dose. The observed differences in mechanical properties are explained on the basis of morphology of the blend. The blend properties were also found to have a strong dependence on nylon content. It was found that the blends rich in nylon had superior mechanical properties, hot oil and solvent resistance, whereas blends with higher HNBR content had better set and heat resistance. The effect of radiation on interaction in these blends was also evaluated and was found to induce possible inter‐chain crosslinking in the blends. Copyright © 2006 Society of Chemical Industry 相似文献
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考察了三羟甲基丙烷三甲基丙烯酸酯(SR350)、三羟甲基丙烷三丙烯酸酯(SR351)作为过氧化物的助交联剂对氢化丁腈橡胶(HNBR)的硫化特性、加工性能、物理机械性能及老化性能的影响,并采用无转子流化仪研究了2种助交联剂的硫化反应动力学。结果表明,添加助交联剂的胶料的门尼粘度下降,硫化程度都有所增加,压缩永久变形性能改善,并且老化后性能保持率变好。其中添加SR351的试样的硫化程度较高,加工性能和压缩永久形变更佳。而助交联剂的存在提高了硫化反应的活化能,加入SR350和SR351胶料的活化能分别为154.76kJ/mol和158.78kJ/mol,表明加入助交联剂的硫化反应速率对温度的依赖性更大。 相似文献
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研究了芳纶浆粕纤维/ART(丙烯酸盐增强型氢化丁腈橡胶)并用对HNBR硫化特性、力学性能、热老化性能以及动态力学性能等的影响。结果表明,芳纶浆粕纤维和ART都能显著提高胶料的交联程度和定伸应力。加入ART会缩短胶料的焦烧时间和正硫化时间;ART/芳纶浆粕并用比为30/4时,硫化胶综合力学性能达到最优;ART/芳纶浆粕纤维并用能显著降低耐3#标准油时的体积变化率和质量变化率;相同应变条件下,ART用量增大,硫化胶弹性模量和损耗因子变低。 相似文献