耐磨橡胶板配方的研究

研究了胶种并用比、硫化体系、炭黑和减磨剂对胶料的耐磨性及力学性能的影响。得到了性能优异的耐磨橡胶板的胶料配方，此耐磨胶板的阿克隆磨耗为0．03cm^3／1．61km。胶料的配方为：NR／BR50／50，S1．0，TT0．5，CZ1．5，RD1．0，ZnO5．0，SA1．0，HAF65。     

基于分形理论的橡胶复合材料磨耗表面形貌表征

利用橡胶高温磨耗试验机,进行不同温度、角度、负荷及路面条件下的高温磨耗试验,获得具有不同形貌的橡胶磨耗试样。借助3D测量显微镜采集橡胶试样表面形貌图像并进行表征,对橡胶表面磨耗形貌图像进行黑白二值化处理,利用分形理论建立多重分形谱分析模型,定量分析不同试验条件下橡胶试样表面磨耗形貌,定性描述表面磨耗形貌分布特点。研究结果表明,橡胶复合材料磨耗表面形貌具有明显的分形特征,橡胶磨耗性能(磨耗量)随着温度、角度、负荷和路面粗糙度增大而增大。     

橡胶磨耗及表面形貌的研究

通过改变温度和转数来研究它们对橡胶磨耗性能的影响。采用扫描电子显微镜和固体核磁共振研究了磨耗表面形貌的演变过程和结构变化的属性。研究表明,转数与磨耗体积几乎呈线性增大的关系;随着温度的升高,磨耗体积有加剧变大的趋势。扫描电镜的图像表明,磨耗花纹起始于硫化胶表面的微裂纹,在应力作用下,裂纹不断增大、加深,最终形成了山脊状的磨耗花纹。固体核磁共振谱图表明阿克隆磨耗主要是物理性结构变化,并没有明显的化学性变化。     

A novel methodology for evaluating wear behavior of rubber composites under combination of sliding and rolling conditions

The wear behavior of tire tread rubber composites has attracted widespread attention of researcher duo to its serious environmental pollution and high frequency of occurrence for a long time. Herein, a new test method is developed, an improved Akron friction testing machine on a laboratory scale was utilized to estimate the wear loss and mechanism of the rubber composites under rolling and sliding coupling condition. The results indicated that the wear loss quickly increases with the increase of the relative sliding velocity. The main wear mechanism, including adhesive, thermofatigue, tear and curl wear, was governed by the thermal deposition of the worn surface. Scanning electron microscope analysis showed thermal decomposition tear region gradually expanded on the worn surface by increasing relative sliding velocity. The heat distribution numerical analysis supported the experimental results, which confirmed that the heat distribution of the worn surface is entirely consistent with the distribution of the thermal decomposition tear region.     

Effects of radiation pretreatments on the rubber adsorption power and reinforcing properties of fillers in rubber compounds

Radiation damage to fillers such as carbon black, graphite and silica induced by high doses of γ‐radiation or neutrons dramatically increases their ability to adsorb rubber irreversibly. In fact, the ‘bound rubber’, ie the amount of non‐extractable rubber which remains irreversibly linked to the filler matrix, increases dramatically in radiation‐treated fillers. The increased adsorption power of radiation‐damaged fillers has been attributed to the formation of a higher concentration of surface defects in the form of trapped free radicals, fullerene‐like structures and other kinds of defects. The mechanical properties of rubber compounds filled with radiation‐treated carbon blacks show a significant increase in their reinforcing effects, in line with the increased ability to form ‘bound rubber’. © 2001 Society of Chemical Industry     

表面活性剂在橡胶中的应用

从胶乳方面的应用和对无机填料的改性2个方面对近年来表面活性剂在橡胶中的应用进行了总结,目前主要研究方向集中在对无机填料的改性方面。无机填料经过适当改性,可以解决其易团聚、难分散、与橡胶相容性差等问题,从而更好地与橡胶结合达到更好的补强效果。重点介绍了表面活性剂对无机填料的改性。     

Kaolin modified with sodium salt of rubber seed oil as a reinforcing filler for blends of natural rubber,polybutadiene rubber and acrylonitrile–butadiene rubber

Blends of natural rubber (NR) and synthetic rubbers are widely used in the rubber industry to meet specific performance requirements. Further, the emerging field of organomodified clay/rubber nanocomposites could provide a host of novel materials having a unique combination of properties to meet various stringent service conditions. Previous studies have shown that at very low dosages, china clay (kaolin) modified with sodium salt of rubber seed oil (SRSO) improved the cure characteristics and physico‐mechanical properties of NR. Results of the present study show improved cure characteristics and physico‐mechanical properties for blends of NR with butadiene rubber and nitrile rubber containing 4 phr of SRSO‐modified kaolin as indicated by reduction in optimum cure time along with higher tensile strength, tensile modulus and elongation at break for their vulcanizates as compared to those containing unmodified kaolin. The SRSO‐modified kaolin/rubber nanocomposites showed improved flex resistance, reduced heat build‐up, tan delta and loss modulus and higher chemical crosslink density index, indicating a reinforcing effect of the SRSO‐modified kaolin, enabling the nanocomposites to have potential industrial applications. © 2015 Society of Chemical Industry     

采用热重和裂解气相色谱-质谱分析方法剖析轮胎硫化胶

通过裂解气相色谱－质谱（PGC－MS）和热重分析（TGA）等方法，对轮胎不同部位的硫化胶进行了一系列彻底地分析。成功利用PGC－MS确定了多组份橡胶的并用比，另外PGC－MS方法也是一种简单而迅速地测定促进剂和防老剂的方法，这种方法不需对硫化胶进行预处理。用TGA的方法可测定硫化胶的含胶率，碳黑含量，抽出物含量以及灰分含量。在轮胎硫化胶分析中与传统的繁琐的化学分析相比，PGC－MS和TGA被证明是一种准确而导致的分析方法。     

Effect of chemically modified waste rubber powder as a filler in natural rubber vulcanizates

Waste rubber powder (RP) was subjected to chemical modification by using different concentrations of oxidizing agents such as nitric acid and 30% hydrogen peroxide solution. This treatment leads to introducing some functional groups onto the surface of RP. The chemically modified RP was incorporated in natural rubber mixes either alone or in combination with carbon black (HAF). The physicomechanical properties of NR vulcanizates obtained were studied and compared to NR vulcanizates filled with untreated RP. It was found that the chemically modified RP improves tensile strength and aging resistance of NR vulcanizates compared with untreated RP. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 30–36, 2004     

Influence of fillers dispersion on friction and wear performance of solution styrene butadiene rubber composites

Development of structure–properties relationships between the fillers/rubber matrix interface chemistry and the dispersion and interfacial adhesion properties of the rubber composites is critical to predict their bulk mechanical and tribological properties. In this paper, three solution styrene butadiene rubber (SSBR) composites containing various fillers with tailored interfacial chemistry were prepared via conventional mixing technique. Subsequently, thermal and structural features of filled SSBR composites were monitored by TG, DSC, XRD, XPS, FESEM and TEM, respectively. Sliding contact experiments were conducted to study tribological properties of styrene butadiene rubber composites under dry and wet conditions. It was shown that the SSBR filled with silicon dioxide nanoparticles significantly reduced both the friction coefficient and the wear against marble block. On the contrary, it exhibited an increased friction coefficient and wear under wet friction conditions due to the specific superior wet‐skid resistance of silicon dioxide nanopartilce filled rubber composites, a good dispersion of silicon dioxide nanopartilce in the rubber matrix and strong interfacial adhesion between nanoparticles and rubber matrix. In addition, the influence of fillers dispersion and interfacial adhesion on friction and wear of styrene butadiene rubber composites was evaluated employing theoretical calculation, and the predicted results were in agreement with the experimental observations. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43589.     

Thermooxidative degradation of methyl methacrylate‐graft‐natural rubber

The thermooxidative degradation of methyl methacrylate‐graft‐natural rubber (MG) at different heating rates (B) has been studied with thermogravimetric analysis in an air environment. The results indicate that the thermooxidative degradation of MG in air is a one‐step reaction. The degradation temperatures increase with B. The initial degradation temperature (T_o) is 0.697B + 350.7; the temperature at the maximum degradation rate, that is, the peak temperature on a differential thermogravimetry curve (T_p), is 0.755B + 368.8; and the final degradation temperature (T_f) is 1.016B + 497.4. The degradation rates at T_p and T_f are not affected by B, and their average values are 46.7 and 99.7%, respectively. The maximum thermooxidative degradation reaction rate, that is, the peak height on a differential thermogravimetry curve (R_p), increases with B. The relationship between B and R_p is R_p = 2.12B + 7.28. The thermooxidative degradation kinetic parameters are calculated with the Doyle model. The reaction energy (E) and frequency factor (A) change with an increasing reaction degree, and the variational trends of the two kinetic parameters are similar. The values of E and A increase remarkably during the initial stage of the reaction, then keep relevantly steady, and finally reach a peak during the last stage. The velocity constants of the thermooxidative degradation vary with the reaction degree and increase with the reaction temperature. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 1227–1232, 2003     

Studies on the strength and wear resistance of tetrapod‐shaped ZnO whisker–reinforced rubber composites

Zinc oxide whisker with a tetrapod shape was treated with a coupling agent using an orthogonal design and was mixed into the substrate of natural rubber to obtain the composites. The results of the experimental tests show that the tensile strength of the composites progressively increases with an increased amount of the related whisker. The experiments also indicate that the rubber reinforced by the tetrapod‐shaped ZnO whisker is distinct isotropy. The wear tests demonstrate that the composites containing ZnO whisker appear to have good wear‐resistance behavior. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 80: 1520–1525, 2001     

Processibility and mechanical properties of micronized polytetrafluoroethylene reinforced silicone rubber composites

Various micronized polytetrafluoroethylene (PTFE) powders were compounded with silicone rubber (MQ) and mechanical properties of the MQ/PTFE composites were evaluated. The fracture surface morphologies of prepared composites were also investigated using scanning electron microscopy (SEM). At a level of only 5 wt %, the fractured surface of MQ/PTFE composites show layered structure morphology. This structure effectively improves the tear strength of MQ but it also led to lower the tensile properties of the composites. The addition of fluorosilicone rubber (FMQ) as compatibilizer, tensile and tear strength of the composites improved considerably. However, tensile properties of the MQ/solution of sodium in liquid ammonia treated PTFE composite decreased compared with those of the untreated one. To investigate the production potential of extrusion process, an electric wire was extruded with MQ/PTFE/FMQ composites. During the curing process, volatile molecules lead to bubble and void formation of extruded layer depending on the filler shapes. The spherical PTFE powder was suitable for extrusion process. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

Resistivity and thermal reproducibility of carbon black and metallic powder filled silicone rubber heaters

Flexible heaters were prepared by extruding platinum‐catalyzed silicone rubber composites with conductive carbon black (CB) and metallic fillers. The conductor resistivity of the extruded heaters decreased in order of conductive titanium dioxide (TiO₂) > aluminum powder ≈ zinc powder > copper powder. Thermoelectric switching phenomena were investigated for the silicone rubber/CB/metallic powder systems. The positive temperature coefficient effect was dependent mainly on the CB content rather than on the content of the metallic powders. Resistivity and thermal reproducibility of the extruded heaters were also investigated by periodically applying AC voltage of 110 V. The heaters containing copper and TiO₂ powders exhibited excellent electrical reproducibility. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 95: 1122–1128, 2005     

Thermo-oxidative ageing and its effect on the network structure and fracture mode of natural rubber vulcanizates

The changes in network structure and fracture mode of unfilled and filled natural rubber vulcanizates, during ageing at 100°C have been studied by chemical analyses and scanning electron microscopy. The fall in properties during ageing is caused mainly by chain scission. The increase in crosslink density during the initial periods of ageing causes an increase in modulus and tensile strength. Carbon black accelerates ageing, probably by surface catalysis. The simple network structure of efficiently vulcanized rubber results in better retention of properties during ageing. Antioxidant retards ageing. The extent of degradation of vulcanizates is reflected in the nature of the fracture surfaces. The roughness of the tensile fracture surface is affected to varying degrees depending upon the ageing resistance of the vulcanizates. However, in tear, the mode of fracture propagation is affected by ageing.     

不同滑滚比下溶聚丁苯橡胶/顺丁橡胶复合材料的磨损行为及其机理

采用机械共混法制备了溶聚丁苯橡胶（SSBR）/顺丁橡胶（BR）复合材料,考察了水存在时SSBR/BR复合材料在不同滑滚比条件下的磨损行为和磨损机理。结果表明,在水存在条件下,当滑滚比较低时,主要发生磨粒磨损;当滑滚比较高时,磨损机理主要为撕裂磨损。同时,随着滑滚比的增大,SSBR/BR复合材料的磨损体积逐渐减小,结合理论计算,分析原因主要是由于随着滑滚比的增大,水压差变大,真实接触面积减小,导致磨损体积减小。     

Failure analysis of rubber toughened epoxy resin

Failure of the blends of epoxy cresol novolac resin (ECN) with varied proportions of carboxy terminated polybutadiene (CTPB) liquid functional rubber was studied. Addition of CTPB improves toughness as reflected in the improvement of tensile, flexural, and impact properties. However, 10 wt % of CTPB was the optimum concentration beyond which a rapid fall of properties, in all cases, was observed. Surface topography of the fractured surfaces, studied by scanning electron microscopy and atomic force microscopy, revealed marked changes in the phase morphology due to addition of rubber and also accounted for the variation of the strength properties. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 87: 861–868, 2003     

不同粒径氧化锌填充丁腈橡胶的摩擦磨损机制

采用机械共混与热模压工艺制备普通氧化锌(c-ZnO)与纳米氧化锌(n-ZnO)填充丁腈橡胶(NBR)复合材料,并对复合材料的硫化特性、力学性能及摩擦磨损性能进行了对比研究。结果表明,用量相同时,与c-ZnO相比,n-ZnO在硬脂酸与硫黄作用下形成较强硫化剂,可延长胶料的硫化时间,有利于提高胶料的加工安全性与流动性。与加入c-ZnO的胶料相比,n-ZnO/NBR复合材料的撕裂强度提高了11.0%,压缩永久变形减小17.3%,邵尔A硬度略微提高,且在干摩擦、油润滑条件下均表现出优异的耐摩擦磨损性能。c-ZnO/NBR复合材料的磨损机制为磨粒磨损和严重的黏着磨损,n-ZnO/NBR复合材料的磨损机制为磨粒磨损和少量的黏着磨损。     

Development and characterization of graphitic carbon nitride as nonblack filler in natural rubber composites

A new type of elastomeric composite containing natural rubber (NR) and graphitic carbon nitride (g-C₃N₄) has been successfully prepared with the reinforced property. The reinforcing effect of g-C₃N₄ in NR composites was examined by cure, mechanical, morphological, and swelling studies. Besides, epoxidized NR with 50-mol % epoxy level (ENR-50) was used as a compatibilizer to enhance the hydrophilic g-C₃N₄ filler capacity for hydrophobic NR composites. At the same filler load level, the mechanical properties of NR/g-C₃N₄ composites, such as tensile strength and tensile modulus, were consistently increased with increased ENR-50 content. To note, the ENR compatibilized composites have shown better-reinforced performance, which has been attributed to the hydrogen bonding interactions between the uncondensed amine groups in g-C₃N₄ and the polar groups in ENR. We believe that these newly prepared NR composites based on g-C₃N₄ as nonblack filler and ENR-50 as compatibilizer can find potential applications in modern day rubber research. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 48136.