新型丁腈酯橡胶的加氢及耐热性能研究

以三苯基膦氯化铑为催化剂,对丁腈酯橡胶(BNBR)进行均相溶液加氢处理,研究催化剂质量分数和反应温度对氢化丁腈酯橡胶(HBNBR)加氢度的影响,并研究BNBR和HBNBR的耐热性能。结果表明:当催化剂质量分数为0.003 8、反应温度为100℃时,HBNBR的加氢度达到99%;与BNBR相比,HBNBR的热稳定性和耐热老化性能大幅提高。     

丁腈橡胶和丁腈酯橡胶性能对比

对丁腈橡胶(NBR)和丁腈酯橡胶(BNBR)热氧老化前后的物理机械性能和动态力学性能进行对比研究,并分析了分子结构对材料热氧老化和动态力学性能的影响。结果表明,NBR和BNBR的物理机械性能相当,热氧老化后BNBR的力学性能更优异,其原因可能是BNBR中酯基热稳定性好。NBR的腈基极性强于BNBR的酯基,侧基极性愈强,其相互作用力愈大,单键内旋转愈困难,链的柔顺性愈差,同时,BNBR的柔性酯基可起到增塑剂的作用,这2个因素导致BNBR在低温下的动态力学性能优于NBR。     

高腈基含量无规羧基丁腈液体橡胶的合成

阐述了以Bd、AN和AA为聚合单体,过硫酸盐B为引发剂,硫醇C为分子质量调节剂的自由基乳液无规羧基丁腈液体橡胶的合成方法。研究了聚合配方及其工艺条件、后处理工艺对聚合物性能的影响。结果表明,过硫酸盐B0.2～0．3份,硫醇C5～6份,乳化剂A3～3．5份,聚合反应温度为（25±2）℃;洗涤剂为不低于90℃的自来水,用量为胶浆的1．5倍,干燥温度为110～130℃时,可以得到Mn为1400±200、结合丙烯腈质量分数为30％-35％、羧基值为0．5～10mmol／g的无规羧基丁腈液体橡胶。     

丁腈酚醛橡胶胶粘剂的研究

通过对一种高温固化的单组分丁腈一酚醛型胶粘剂的研究,讨论了酚醛树脂用量、硫化压力对胶粘剂粘接性能的影响;考核了胶粘剂的综合性能。结果表明,丁腈橡胶和酚醛树脂的用量比例在一定范围内有最佳值;剥离强度随硫化压力的增大而提高,但当硫化压力大于40MPa时,再增大压力剥离强度增加趋势不显著。     

丁腈再生橡胶在光面轮胎胎面胶中的应用

研究丁腈再生橡胶在光面轮胎胎面胶中的应用。结果表明：在光面轮胎胎面胶中加入丁腈再生橡胶,胶料的硫化速度变化不大,拉伸性能和耐磨性能略有下降,耐液体（油）介质性能明显提高;试验轮胎粘石子问题解决,使用性能优于生产轮胎,生产成本降低。     

含腈基橡胶耐低温性能和耐油性能的研究

对比丙烯腈含量接近的丁腈橡胶(NBR)、氢化丁腈橡胶(HNBR)和丁腈酯橡胶(BNBR)的各项性能,尤其是硫化胶的耐低温性能和耐油性能。结果表明:HNBR由于分子链规整性较高,其硫化胶具有较高的强度和较低的弹性;与NBR硫化胶相比,BNBR硫化胶的各项物理性能略好;3种含腈基橡胶硫化胶中,BNBR和NBR硫化胶的耐低温性能更好,HNBR硫化胶的耐油性能更好。     

饱和丁腈与丁腈的耐温和适应对比性试验对比

本文研究的主要目的是,对饱和丁腈(HSN)与丁腈橡胶(NBR)在硫化氢适应性方面作定量对比,并比较二者应用温度范围。为此,提出两个问题:HSN是否比NBR更适合于H_2S,HSN的应用温度极限是否比NBR的高。本文将证实以下结论:通过H_2S与HSN的C≡C和NBR的C=C/C≡N发生加成反     

超声波对乳液聚合丁腈胶的影响研究

研究了超声波作用时间对乳液聚合丁腈胶固含量、转化率的影响,对丁腈胶的微观结构进行了红外测试分析。结果表明,随着超声波作用时间的延长,聚合物的固含量和转化率增加,超声波作用的反应体系所得聚合物的微观结构与传统乳液聚合所得聚合物的微观结构一致。     

聚合温度对丁腈橡胶性能的影响

采用兰州石化公司生产的丁腈橡胶N41乳液聚合配方,考察了不同聚合温度对反应时间的影响,测定了橡胶链化学结构组成、凝胶含量、生胶门尼粘度和硫化胶力学性能.结果表明：随聚合温度的升高,反应时间缩短,硫化胶的拉伸强度和300%定伸应力提高,扯断伸长率降低.反应后期聚合温度的升高,导致凝胶含量增加,生胶门尼粘度升高.     

Compatibility study of polypropylene and acrylonitrile butadiene rubber blends

Blends of polypropylene (PP) and acrylonitrile butadiene rubber (NBR) were prepared with different weight compositions with a plasticorder at 180°C at a rotor speed of 60 rpm for 8 min. The physicomechanical properties and mass swell of the prepared blends were investigated with special reference to the effects of the blend ratio. The prepared epoxidized linseed oil (EL) (i.e., E_0.5L, E₁L, E_1.5L, and E₂L using 0.5, 1, 1.5, and 2 mol H₂O₂/mole of unsaturation in linseed oil) and maleic acid anhydride (MAH) were melt mixed in various contents (i.e., 1, 5, 10, and 15 wt %) with a PP/NBR blend with a weight ratio of 70/30 and used as compatibilizers. The effect of the compatibilizer contents on the physicomechanical properties and mass swell of the binary blend was investigated. With an increase in the compatibilizer content up to 10 wt %, the blend showed an improvement in the physicomechanical properties and reduced mass swell in comparison with the uncompatibilized one. The addition of a compatibilizer beyond 10 wt % did not improve the blend properties any further. The efficiency of the compatibilizers (10 wt %) was also evaluated by studies of phase morphology (scanning electron microscopy). © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Recycling of chrome‐tanned leather waste in acrylonitrile butadiene rubber

Chrome‐tanned leather waste generated in huge amount from leather industry causing environmental problem; this leather waste was used as filler in acrylonitrile butadiene rubber before treatment and after treatment with ammonia solution and sodium formate. Different formulations of acrylonitrile butadiene rubber/leather waste (untreated–treated with ammonia solution—treated with sodium formate) composites are prepared. The formed composites exhibit a considerable improvement in some of their properties such as rheometric characteristics especially with composites loaded with treated leather waste. Tensile strength, modulus at 100% elongation, hardness, and Young's modulus were improved for composite loaded with treated leather. Crosslinking density in toluene was increased by the incorporation of leather wastes treated or untreated resulting in decreases in swelling equilibrium. Distinct increase in the ageing coefficient and the thermal stability for composites loaded with both treated and untreated leather. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Cure characteristics,morphology, and mechanical properties of ethylene–propylene–diene–monomer rubber/acrylonitrile butadiene rubber blends

Blends based on ethylene–propylene–diene monomer rubber (EPDM) and acrylonitrile butadiene rubber (NBR) was prepared. Sulfur was used as the vulcanizing agent. The effects of blend ratio on the cure characteristics and mechanical properties, such as stress–strain behavior, tensile strength, elongation at break, hardness, rebound resilience, and abrasion resistance have been investigated. Tensile and tear strength showed synergism for the blend containing 30% of NBR, which has been explained in terms of morphology of the blends attested by scanning electron micrographs. A relatively cocontinuous morphology was observed for 70 : 30, EPDM/NBR blend system. The experimental results have been compared with the relevant theoretical models. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007     

Effect of acrylonitrile content of acrylonitrile butadiene rubber on mechanical and thermal properties of dynamically vulcanized poly(lactic acid) blends

We report here the morphology, thermal and tensile properties of poly(lactic acid) (PLA) blends composed of acrylonitrile butadiene rubber (NBR) with different acrylonitrile contents with/without dynamic vulcanization by dicumyl peroxide (DCP). The interfacial tension of PLA and NBR measured by contact angle measurement decreased as the acrylonitrile content of NBR decreased. Likewise, SEM images showed that the rubber particle size reduced with decreasing acrylonitrile content owing to the stronger interfacial adhesion between the PLA matrix and NBR domains. Incorporation of DCP at 1.0 phr for dynamic vulcanization led to higher crosslink density and, in turn, optimal tensile strength and tensile toughness as a result of the action of PLA‐NBR copolymer as a reactive compatibilizer. The dynamic vulcanization of the blends containing low acrylonitrile NBR gave the most improved tensile properties because the free radicals from DCP decomposition preferentially attacked the allylic hydrogen atoms or double bonds of the butadiene backbone. Accordingly, more NBR macroradicals were generated and probably more PLA‐NBR copolymers were produced. Moreover, further addition of DCP at 2.0 phr provided a large amount of crosslinked NBR gel, which significantly degraded the tensile properties. From the DSC results, dynamic vulcanization lowered the cold crystallization temperature, implying an improvement of cold crystallization. Finally, TGA results showed a higher degradation temperature as a function of DCP content, which suggested that thermal stability increased due to stronger interfacial adhesion as well as higher gel content. © 2019 Society of Chemical Industry     

乳聚丁苯橡胶后处理工艺技术改进

乳聚丁苯橡胶生产中,后处理单元是决定产品质量的关键环节。针对后处理单元非计划停车频繁、运行周期短的状况,从工艺、设备、现场管理等方面进行了分析,找出影响后处理单元稳定运行的主要因素并进行了改进。     

溴化丁基橡胶/丁腈橡胶并用胶微观结构及性能研究

用改性沥青作相容剂,研究溴化丁基橡胶(BIIR)/丁腈橡胶(NBR)并用胶的微观结构和性能。结果表明:与未添加改性沥青CJ-100的BIIR/NBR并用胶相比,添加改性沥青CJ-100的BIIR/NBR并用胶的相容性较好,加工性能改善,气密性、耐屈挠和耐臭氧性能提高;添加5份改性沥青CJ-100的BIIR/NBR(并用比为80/20)并用胶物理性能、气密性、耐屈挠和耐臭氧性能较好,气密性接近全BIIR胶料,有望用于全钢载重子午线轮胎气密层。     

丁二烯丙烯腈聚合过程中间产物性能研究

采用兰州石化公司生产的丁腈橡胶N41乳液聚合配方,考察了聚合反应单体转化率随反应时间的变化,测定了生胶的结合丙烯腈含量、分子质量及其分布、玻璃化转变温度、微凝胶含量和门尼黏度等性能,结果表明:随着转化率的升高,生胶结合丙烯腈含量降低,耐寒性能变好,门尼黏度、相对分子质量及其分布指数升高,当转化率达到86%时,生胶的门尼黏度达到产品指标上限。     

Preparation of epoxidized acrylonitrile butadiene rubber and its compatibilization effect on water-swellable rubber composites

In this research, water-swellable rubbers (WSRs) were prepared by the blending of acrylonitrile butadiene rubber (NBR) with epoxidized acrylonitrile butadiene rubber (ENBR), precipitated silica, vulcanizing agents, and polyacrylic acid sodium (PAAS) as superabsorbent polymers (SAPs). ENBR was prepared with a molybdenum trioxide catalyst and a tert-butyl hydroperoxide oxidant through a free-radical reaction under specific conditions and was used as a compatibilizer to improve the interfacial adhesion of the NBR matrix and hydrophilic components of the WSRs. Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy were used to analyze the structure and properties of ENBR. The dispersion of silica and SAPs in the rubber matrix was investigated by transmission electron microscopy. The presence of ENBR enhanced the water-absorption properties of the WSRs. The NBR–ENBR composites exhibited a higher mechanical performance after water absorption than that without ENBR. Both the swelling ratio and the absorption rate increased with the ENBR content. When the weight ratio of NBR–ENBR was 25/75, an equilibrium swelling ratio of 172% (13% higher than that of the sample without ENBR) was obtained. Scanning electron microscopy analysis revealed that the addition of ENBR improved the compatibility between the SAPs and the NBR matrix. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47694.     

Aluminum silicate fibers impregnated acrylonitrile butadiene rubber composites: Ablation,thermal transport/stability,and mechanical inspection

Variant concentrations of ceramic fibers (CerFs) were incorporated into acrylonitrile butadiene rubber (NBR) to fabricate elastomeric ablative composites for ultrahigh temperature applications. The CerFs introduction into the polymer matrix has enhanced the ablation resistance up to 59% and successfully reduced the backface temperature of the polymer composite up to 110^oC during the ultrahigh temperature ablation investigation. Thermal decomposition of the polymer composites was diminished up to 10% with increasing fiber concentration in the rubber matrix. Thermal conductivity was reduced equal to 63% while thermal impedance was enhanced up to 84% with the utmost fiber incorporation into the NBR matrix. The CerFs have adversely affected the mechanical properties of NBR matrix due to their brittle/inert nature and weak interface bonding with the host matrix. Scanning electron microscopy along with the energy dispersive x‐ray spectroscopy was used to examine the ablated specimens and the fiber dispersion within the host matrix. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 4392–4400, 2013