芳纶短纤维增强天然橡胶复合材料性能研究

研究添加不同用量的芳纶短纤维/天然橡胶(NR)复合材料的性能。结果表明,NR复合材料的性能随着芳纶短纤维用量的增大先提高再下降;添加2份芳纶短纤维时复合材料的物理性能较好,磨耗性能也较优;添加芳纶短纤维能够使复合材料的抗湿滑性能变好,滚动阻力增大,导热性降低。     

纳米MH/AF/NBR复合材料物理力学性能及耐热阻燃机理

为了获得具有较好物理力学性能和耐热阻燃性能的橡胶密封材料,以NBR、芳纶纤维(AF)和纳米Mg(OH)₂(MH)为主要原料制备了纳米MH/AF/NBR复合材料.研究了纳米MH和AF不同配比时,复合材料的物理力学性能变化、耐热阻燃性能变化.结果表明:纳米MH对复合材料内部结构有很好的补强作用,而AF添加量较多时,与橡胶的结合强度有变差的趋势.不同配比的纳米MH与AF能够有效改善NBR的物理力学性能.当纳米MH与AF填料配比份数配比为20/10时,复合材料的拉伸强度、定伸应力可以提高4%左右,永久压缩变形降低1%左右,当纳米MH/AF份数配比为30/10时,硬度提高到73度.比较发现纳米MH的阻燃性能要优于AF,纳米MH/AF份数配比为10/10时,复合材料分解温度提高了近20℃,MH/AF填料的加入改善了NBR原有的热稳定性,且复合材料燃烧时烟气生成量较小,为该类复合材料在密封等领域进一步应用奠定了基础.     

芳纶纤维增强丁腈橡胶的摩擦性能

研究了芳纶纤维增强丁腈橡胶(NBR)复合材料的物理机械性能和摩擦性能,并用扫描电子显微镜分析了芳纶纤维增强NBR复合材料的磨损表面和磨屑形貌。结果表明,芳纶的加入提高了NBR的拉伸强度;随着芳纶用量的增大,复合材料的扯断伸长率降低;芳纶的加入降低了NBR的摩擦系数和磨损率;当芳纶用量为20份时,复合材料的综合性能最佳。加入芳纶对NBR摩擦磨损形式的改变是NBR摩擦性能提高的重要原因。     

Properties of alumina nanoparticle‐filled nitrile‐butadiene‐rubber/phenolic‐resin blend prepared by melt mixing

Effect of alumina nanoparticle (ANP) on the properties of rubber compounds based on nitrile‐butadiene‐rubber (NBR) and NBR/phenolic‐resin (PH) blend is examined. To investigate the surface characteristics of the nanoparticles on the performance of nanoalumina‐filled compounds, trimethoxyvinylsilane (MVS) is attached chemically on the surface of ANP through an appropriate functionalization process. Various NBR and NBR/PH compounds filled with ANP and functionalized ANP (f‐ANP) are prepared via melt mixing using traditional open two‐roll mill. Microscopic analysis carried out by scanning electron microscopy (SEM) and transmission electron microscopy (TEM) reveals good dispersion of nanoalumina within the rubber matrix, indicating the effectiveness of the melt mixing for fabrication of the rubber/alumina nanocomposites. Nanocomposites of NBR and NBR/PH are subjected to various physical and mechanical tests including swelling, tensile, abrasion, and thermal tests and the role of ANP and f‐ANP on these properties are discussed. The results obtained based on this analysis suggest that as‐received ANP can provide good interaction with NBR possibly due to hydrogen bonding between hydroxyl group present on the nanoparticle surface and acrylonitrile group of NBR. POLYM. COMPOS., 2009. © 2009 Society of Plastics Engineers     

Synthesis and characterization of the novel meta‐modified aramid fibers with liquid crystalline properties

To improve the interfacial adhesion between the meta‐aramid fibers and the matrix, the new method of interfacial polymerization was used to complete the aramid's surface modification. Two new kinds of grafted fibers which had liquid crystalline properties were prepared. The structure and properties of the aramid fibers before and after modification were characterized by scanning electron microscope (SEM), Fourier transform infrared, differential scanning calorimetry, and polarizing optical microscope. The surface of grafted aramid fibers was very rough. The range of liquid crystalline phase of the grafted fibers AF‐1 and AF‐2 on the cooling scan, respectively, is from 147 to 209°C and from 163 to 221°C. It was novel that the grafted fibers with rigid‐rod structure had typical nematic texture. The grafted aramid fibers as the ideal substitute material of asbestos were used as reinforcing fibers in nitrile butadiene rubber (NBR) matrix. Combining with NBR, the composites reinforced with the unmodified and grafted aramid fibers were synthesized. The micrographs of the composites' fractured surface were studied by SEM. The mechanical properties of the grafted fibers/NBR composites were superior to the unmodified fibers/NBR composites. POLYM. COMPOS., 2012. © 2012 Society of Plastics Engineers     

纳米二氧化锆增强丁腈橡胶力学性能的分子动力学模拟

采用分子动力学模拟的方法建立了纳米二氧化锆增强丁腈橡胶（NBR）复合材料的分子模型,对比分析了外部填充、原位填充以及原位填充且经过偶联化处理三种形态的二氧化锆对NBR力学性能的增强效果,从原子层面探讨了定子橡胶力学性能的内在增强机制。结果表明,相比于纯NBR,三种形态二氧化锆的引入均显著改善了NBR的力学性能。原位填充纳米二氧化锆的表面羟基与NBR形成氢键型偶极相互作用,表面活性偶联剂双-（3-三乙氧基硅烷丙基）四硫化物的加入进一步提供了与橡胶基质之间的化学桥接,从而大大提升了NBR基质的力学性能。与纯NBR体系相比,原位填充且经过偶联化处理的二氧化锆增强NBR的力学性能表现最佳,复合体系的杨氏模量、体积模量和剪切模量均提升得最多。通过界面结合能、非键合能、均方位移和扩散系数的计算,验证了纳米二氧化锆的添加改善了定子橡胶力学性能的结论。     

Mechanical,morphological and thermal properties of short carbon and aramid fibres-filled bromo-isobutylene-isoprene rubber vulcanised with 4, 4’ bis(maleimido)diphenylmethane

ABSTRACT

This paper describes the use of a combination of 4, 4’ bis(maleimido)diphenylmethane and ZnO as a high-temperature processable vulcanising agent for the short aramid and carbon fibre-filled bromo-isobutylene-isoprene rubber. The fibre breakage analysis, cure characteristics, mechanical, thermal and morphological properties of the composites were evaluated with different fibre loading. The fibre breakage analyses revealed that the aramid fibres have good length retention property compared to carbon fibres. The morphological analysis of the extracted aramid fibres showed severe surface roughness primarily due to fibrillation after shear mixing. The fibrillated aramid fibres lead to aggregation and poor dispersion of the fibres in the rubber matrix. However, fibrillation imparted surface roughness and increased surface area on the aramid fibres which improved the fibre–matrix interaction via mechanical anchoring. On the other hand, the carbon fibre-filled composite showed poor fibre–matrix interaction and inferior strength and modulus.     

Friction properties of graphene reinforced nitrile rubber composites after thermal oxidation aging: Experiment and molecular dynamics simulation

We established friction models for pure NBR, GNS/NBR, and GO/NBR composites through molecular dynamics (MD) simulation. Our study focused on the impact of GNS and GO on the friction properties of nitrile rubber (NBR) composite materials after undergoing thermal oxygen aging. Based on the simulation results, it can be observed that the GNS/NBR and GO/NBR composites' coefficient of friction (COF) decreases by 20.8% and 24.8%, respectively, at 348 K. Additionally, the abrasion rate is reduced by 17.4% and 25.7%, respectively, for the same composites. Adding GNS and GO can effectively improve the friction performance of the NBR composite system, and compared with GNS, GO shows a better enhancement effect. Pure NBR and GO/NBR composite materials were prepared by mechanical blending method, and the friction properties of GO-enhanced NBR composite materials were studied. The experimental results show that the GO/NBR composite material can maintain a low friction and wear coefficient after thermal and oxygen aging. It shows that adding GO can effectively improve the friction properties of NBR composite systems and slow down the weakening effect of aging on the friction properties of NBR composite materials. This is because the GO surface contains wealthy functional groups such as epoxy groups, which enhances the binding strength between the GO and NBR interface so that the GO/NBR composite material exhibits better friction properties and thermal oxygen aging resistance. In addition, the wear surface was characterized by scanning electron microscopy (SEM), revealing the damage mechanism of friction and wear of NBR composite materials.     

基于两种丁腈橡胶复合填料的高性能离合器摩擦材料的研究

以丁腈胶乳改性水基酚醛树脂为胶粘剂,分别以玻璃纤维和复合包芯纱纤维为增强材料,采用两种新型丁腈复合填料[含9%硫化丁腈橡胶(NBR)和含20%未硫化NBR]为主要填料制备高性能离合器摩擦材料。实验结果表明,当m(9%硫化NBR)∶m(20%未硫化NBR)=1∶1[即W(NBR)≈16%]时,制取的摩擦材料具有良好的摩擦磨损性能、适中的硬度、良好的冲击强度和较低的噪音。     

添加剂对丁腈橡胶结构和性能的影响

丁腈橡胶经过硫化剂硫化并使用补强填充剂及其它填加剂后,其定伸强度、弹性、刚度、抗拉强度、耐候性、耐老化性等一系列物理机械性能都会大大提高,详细论述了合理选用添加剂及其协调配合使用对丁腈橡胶结构和性能的影响,提高丁腈橡胶的综合性能,对实际生产和应用提供了有效的指导作用。     

NBR/革屑复合材料性能研究

将制革工艺中的削匀革屑（LS）与丁腈橡胶（NBR）混炼并压板制备成复合材料（NBR/LS）,通过测定复合材料物理力学性能考察工艺条件对材料性能的影响。分别对NBR纯胶和NBR/LS复合材料的热性能进行了表征。测试结果表明：NBR/LS复合材料制备中压板时间、温度和革屑含量均对NBR/LS复合材料有较大影响;最佳力学性能出现在压板时间为30 min,温度为150℃,革屑用量为15份的工艺条件下;革屑的加入使得NBR的玻璃化转变温度（Tg）从-33.6℃升高至-31.0℃,复合材料的tanδ峰值和损耗模量明显降低;NBR/LS复合材料比NBR纯胶有较好的热稳定性能。     

Enhanced interfacial adhesion of aramid fiber reinforced rubber composites through bio-inspired surface modification and aramid nanofiber coating

In order to improve the interfacial adhesion between aramid fiber (AF) and rubber matrix, a simple and facile method of aramid nanofiber (ANF) coating is demonstrated in this article. Tannic acid (TA) and polyethyleneimine (PEI) are polymerized in an alkaline solution to form a thin TA/PEI (TP) layer that is deposited on the surface of AF to introduce functional groups such as hydroxyl and amino groups. Then, the ANF coating is utilized to construct nanostructures on the surface of AF to improve the interfacial adhesion between the fiber and the rubber. Through hydrogen bonding and/or π-π stacking between the TP layer and the ANF, the ANF coating is firmly attached to the surface of AF. Compared with the untreated fiber, the interfacial adhesion of AF coated with ANF after 1, 3, 5, 7, 9 deposition cycles is increased by 27.8%, 29.1%, 31.5%, 43.1%, and 30.3%, and the mechanical properties of the fibers remain almost unchanged. This method shows its advantages of simple, facile, and time-effective, which is of great significance for industrial applications.     

Aramid pulp reinforced hydrogenated nitrile butadiene rubber composites with ionic liquid compatibilizers

Although carbon black is an effective reinforcement for most rubbers, its replacement by other fillers would be beneficial. Aramid fibers are used in a range of applications in the rubber industry, providing dimensional stability prior to vulcanization and improving the mechanical properties of the elastomeric product. Nevertheless, their relatively inert surface is an obstacle in the exploitation of their full potential. In this work, two ionic liquids were investigated as compatibilizers in the preparation of hydrogenated nitrile butadiene rubber composites with aramid pulp and carbon black fillers. The materials were characterized using swelling, hardness and tensile tests, differential scanning calorimetry, thermal gravimetric analysis, and infrared spectroscopy. The carbon black-free composite prepared from aramid pulp treated with 1.0 wt% of 1-carboxymethyl-3-methylimidazolium chloride outperformed all other studied materials, presenting a higher modulus at 100% strain (7.31 MPa), while maintaining high strain at break. Thus, ionic liquids were found to potentialize the aramid reinforcement effect in these rubber composites. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 137, 48702.     

配合体系对丁腈橡胶胶料性能的影响

研究生胶体系、防护体系、增塑体系、硫化体系对丁腈橡胶（NBR）硫化胶性能的影响。结果表明,当单独采用丙烯腈含量为29%的NBR2707或NBR N640时,NBR硫化胶的耐油性能优异,但耐低温性能较差;适宜的防护体系可以在不影响NBR硫化胶的力学性能的前提下,提高其耐油性能和抗压缩永久变形性能;采用增塑剂DOS/TP-95体系的NBR硫化胶的力学性能和耐油性能优于单独采用增塑剂DOS或TP-95的NBR硫化胶;采用过氧化物DCP/甲基丙烯酸镁和过氧化物BIPB/硫黄给予体硫化体系的NBR硫化胶的综合性能优异。     

改性粉煤灰补强橡胶的研究

以硅酸钠改性粉煤灰作为补强剂,研究了其补强天然橡胶(NR)、丁腈橡胶(NBR)的工艺及产品的性能。结果表明,粉煤灰改性过程中的酸碱性条件、搅拌速度以及改性粉煤灰的用量都对NBR的补强作用有较大影响,而改性粉煤灰对NR的补强作用并不明显。     

Synergistic reinforcement of NBR by hybrid filler system including organoclay and nano‐CaCO3

Rubber nanocomposites containing one type of nanofiller are common and are widely established in the research field. In this study, nitrile rubber (NBR) based ternary nanocomposites containing modified silicate (Cloisite 30B) and also nano‐calcium carbonate (nano‐CaCO₃) were prepared using a laboratory internal mixer (simple melt mixing). Effects of the hybrid filler system (filler phase have two kind of fillers) on the cure rheometry, morphology, swelling, and mechanical and dynamic–mechanical properties of the NBR were investigated. Concentration of nano‐CaCO₃ [0, 5, 10, and 15 parts per one hundred parts of rubber by weight (phr)] and organoclay (0, 3, and 6 phr) in NBR was varied. The microstructure and homogeneity of the compounds were confirmed by studying the dispersion of nanoparticles in NBR via X‐ray diffraction and field emission scanning electron microscopy. Based on the results of morphology and mechanical properties, the dual‐filler phase nanocomposites (hybrid nanocomposite) have higher performance in comparison with single‐filler phase nanocomposites. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42744.     

Dielectric and mechanical properties of polystyrene/acrylonitrile–butadiene rubber blends

The dielectric and mechanical properties of polystyrene(PS)/acrylonitrile–butadiene rubber (NBR) blends were studied with the aim of improving the insulation properties of NBR. Compatibility investigations, performed with viscosity and dielectric methods and confirmed with the calculated heat of mixing, indicated that such blends were incompatible. To overcome the problem of phase separation between NBR and PS, we chose epoxidized soya bean oil to act as a compatibilizer and added 3% to the blends under investigation. This led to the conclusion that a sample containing 10% PS (either pure or scrap) possessed the most suitable electrical and mechanical properties. For this reason, the sample was chosen for studying the effect of the addition of three types of fillers (quartz, talc, and calcium carbonate) in increasing quantities (up to 80 phr) on the dielectric and mechanical properties. The variation of the dielectric properties with temperature (20–60°C) was also investigated. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 540–552, 2002     

Mechanical and tribological properties of nitrile rubber filled with modified molybdenum disulphide

In this work, cetyl trimethyl ammonium bromide (CTAB), silane coupling agent (KH570) and polyethylene glycol (PEG) were used to modify the surface property of molybdenum disulphide (MoS₂). MoS₂/nitrile rubber (NBR) composites were directly prepared by mechanical blending. Meanwhile, the effects of loading content of MoS₂, the kinds of modifiers on the mechanical and tribological properties of the composites were evaluated. The dispersion of fillers in rubber matrix and the worn surface of the composites were analysed by SEM. Results showed that the properties of MoS₂/NBR composites prepared by CTAB modified MoS₂ were superior to that of KH570 or PEG modified MoS₂ and unmodified MoS₂ because of strong opposite charges attraction between cetyl trimethyl ammonium cation and MoS₂ surface. When adding 10?phr CTAB modified MoS₂ in rubber matrix, the dispersion of filler was optimum, and the coefficient of friction of composite was the lowest in the prepared composites.     

Si-69改性白炭黑增强受阻酚／丁腈橡胶复合材料的制备与性能研究

在丁腈橡胶（NBR）中加入受阻酚AO—80和不同份数Si-69改性的白炭黑,制备了NBR／AO-80／白炭黑／Si-69复合材料。利用差示扫描量热（DSC）,动态力学分析（DMA）,力学性能测试等手段对复合材料动态力学性能及力学性能进行了研究。结果表明：与纯NBR相比。复合材料玻璃化转变温度向高温移动。损耗峰峰值有所降低,损耗峰位置向高温移动,有效阻尼温度区域有所拓宽,其损耗峰峰值高于1．25。有效阻尼温度区域（≥0．3）大于32℃,表明复合材料具有良好阻尼性能;与NBR／AO-80复合材料和纯NBR相比,复合材料力学性能有大幅度提高,拉伸强度达到28．3MPa,撕裂强度达到44．8kN／m。     

HPVC/NBR并用透明鞋底的研制

研究了采用高聚合度聚氯乙烯(HPVC)与丁腈橡胶(NBR)并用制造透明鞋底的过程,讨论了材料折光率、稳定剂、HPVC/NBR并用比、补强剂和硫化体系等因素对鞋底的透明性和力学性能的影响。实验结果表明:选择共混比HPVC/NBR=70/30(质量比)、TS_3白炭黑30份、超细CaCO_3 3～5份及适量助剂.可制得透明性和力学性能较好的耐油透明鞋底;含铅类稳定剂不能在硫黄硫化的HPVC/NBR透明鞋底中使用;硫化体系对透明鞋底的力学性能影响不大。