Formulation and characterization of leather and rubber wastes composites

Residues from footwear roughing and carding operations represent 5–15% (w/w) of the solid wastes generated by shoe‐making companies. These wastes are mainly composed by chromium tanned leather and sole materials, and are mostly land filled. Sometimes leaching tests show these wastes as hazardous due to chromium in the leachate. This work aims at a more sustainable option for these wastes by recycling them in styrene butadiene rubber (SBR) and acrylonitrile butadiene rubber (NBR). Thus, they were charged with: (i) ≤1 mm leather waste fibers in the range of 10–25 parts per hundred parts of rubber (phr); and (ii) leather and soles industrial carding and roughing wastes in the range of 20–100 phr. The leather waste fibers‐rubber composites tear strength is increased till 25 phr and both tension and elongation at break decrease within the acceptable range till 12.5 phr for SBR and 15 phr for NBR. In the case of leather and sole carding and roughing wastes, composites tear strength increases till 100 phr, and tension and elongation decrease within the acceptable range till 20 phr. The composite materials at the end of their life cycle may be considered inert or non‐hazardous wastes. POLYM. ENG. SCI., 2011. © 2011 Society of Plastics Engineers     

纳米二氧化钛填充橡胶复合材料的分散结构与性能

用粒径为20～40nm的纳米二氧化钛(B—TiO2)填充天然橡胶(NR)和丁腈橡胶(NBR)制备了橡胶复合材料,研究了B—TiO2在橡胶基体中的分散结构、复合材料的力学性能以及抗菌性能,并与德国Degussa公司的催化剂纳米TiO2(D—TiO2)进行了对比。结果表明,B—TiO2在NR和NBR中表现出良好的分散,绝大多数B—TiO2在橡胶中聚集体尺寸小于100nm,特别是在NR中B—TiO2分散颗粒大小与其原生颗粒大小相近,明显优于D—TiO2在NR中的分散;在B—TiO2用量小的情况下,橡胶复合材料的力学性能基本不受B—TiO2的影响。D—TiO2对橡胶复合材料的老化性能也没有影响。橡胶基体中填充B—TiO2后,其抗菌性能明显提高,当用量超过2份(质量)时,其抗菌性能已经达到较高的水平;D—TiO2／NR抗菌效果与B—TiO2／NR的抗菌效果相当,热氧老化不影响橡胶复合材料中TiO2发挥其抗菌特性。     

丙烯酸酯橡胶的配合

介绍了国内丙烯酸酯橡胶的生产和应用状况,对应用中常见的配合技术问题进行了分析探讨,提出了相应的措施和方法,即严格控制生胶质量,选择中性或偏碱性补强填充剂,采用皂／硫黄并用,N,N′－二（亚肉桂基－1,6－己二胺）硫化体系或硫化剂TCY作为硫化体系,并注意选择适当的防老剂,加工助剂和功能性助剂以提高胶料的耐热老化性和加工性能。     

水滑石对轮胎胎侧橡胶复合材料微观形貌与性能的影响

将水滑石（LDHs）加入到轮胎胎侧橡胶中制得LDHs/橡胶复合材料,研究了LDHs在橡胶复合材料中的分散状态及对胎侧橡胶复合材料的硫化特性、力学性能和耐老化性能的影响。结果表明,LDHs穿插在炭黑粒子之间,形成均匀分散;LDHs可以促进硫化,缩短橡胶复合材料的硫化时间,并提高其定伸应力和撕裂强度、改善耐老化性能。当LDHs的用量为4份（质量）时,与未添加LDHs橡胶复合材料相比的抗张积老化系数提高了25.7%。     

Coconut-fiber-reinforced rubber composites

Different formulations of rubber with chopped coconut fiber (treated and untreated) as reinforcing agent were prepared. These reinforced systems were vulcanized at 153°C and the properties of the vulcanizates were studied by stress–strain, shore A hardness, and abrasion loss measurements. The bonding between the rubber and fillers were improved by the addition of bonding agents. The bonding effect of different bonding agents were compared. The reinforcing property of the treated fiber was compared with the untreated one. Aging resistance of the composites were studied. The fracture surfaces have been studied by scanning electronmicroscopy (SEM) and the failure mechanism has been explained.     

废聚丙烯/废轮胎胶粉/废尼龙短纤维复合材料I.配方

用双螺杆挤出机制备了废聚丙烯／废轮胎胶粉／废尼龙短纤维(WPP／GRT／WSF)复合材料,通过正交实验得出了制备该复合材料的最佳配方,讨论了增容剂用量、氯化聚丙烯的含氯质量分数、GRT用量及其粒径、WSF用量及预处理对该复合材料力学性能的影响。结果表明,制备该复合材料的最佳配方(质量份,下同)是WPP100,GRT30,WSF8,二甲基二硫代氨基甲酸锌、二硫化二苯并噻唑、多乙烯多胺及重油用量依次为0.6,1.2,0．3,2,聚丙烯接枝马来酸酐、氯化聚丙烯用量依次为8.4;在最佳配方下,该复合材料的非缺口冲击强度为25.2kJ／m^2,拉伸强度为13．6MPa;GRT用量为30份时,该复合材料的拉伸强度和非缺口冲击强度最大,GRT的最佳粒径为40目;WSF经D法预处理后,提高了该复合材料的力学性能,拉伸强度为16．3MPa,非缺口冲击强度为27．8kJ／m^2。     

Preparation,morphology and properties of natural rubber composites filled with untreated short jute fibres

Green composites were obtained by incorporation of short jute fibres in natural rubber matrix using a laboratory two-roll mill. The influence of untreated fibre content (1, 2.5, 5, 7.5 and 10 phr) on the mechanical properties, dynamic mechanical properties, swelling properties was examined. The behaviour of prepared green composites under cyclic compression was also investigated. Fibre dispersion in rubber matrix was studied by scanning electron microscopy. The highest tensile strength (21.1 MPa) and highest tear strength (39.9 N/mm) were found for composites containing 2.5 and 5 phr of short jute fibres, respectively. The results also suggested that increasing fibrous filler content resulted in increasing of tensile moduli 100, 200 and 300 % of elongation and hardness, and decreasing of rebound resilience and abrasion resistance of prepared jute/natural rubber composites. The cyclic compression test showed that increasing the amount of short jute fibres in the rubber matrix is related to increase of the energy dissipated in the composite. The incorporation of short jute fibres into the rubber matrix improves the stiffness of the composites, and it is related to the interaction between fibre surface and rubber matrix. The application of short fibres in higher amounts leads to formation of fibre agglomerates reducing the mobility of the rubber polymer chains. The mentioned agglomerates act as defects in rubber matrix, which caused decreasing of some properties, e.g. relative elongation at break.     

注射模压法胶帽的配方研究

对采用注射模压法生产胶帽的配方进行研究,确定配方为：IR／SBR50／50;氧化锌5：硬脂数2;高碳磨炭黑20;通用炭黑20;轻质碳酸钙40;安息香酸2．0;凡士林10;硫黄0．4;促进剂CZ1．5;促进剂DM0．6;防老剂RD1．5。由此配方生产的胶幅,其产品的外观和物理性能均满足要求。     

汽车用橡胶空气弹簧胶料配方的研究

介绍了汽车用橡胶空气弹簧胶料配方的研究。通过小配合和大配合试验确定的汽车用橡胶空气弹簧胶料配方为：CIIR50;NR 50;炭黑N4330 45;增粘剂TKO－80 2．0;芳烃油5．0;粘合剂RH2．0;沥青（高软化点）2．0;防老剂3．0;硫化体系9．30;其它1．8,合计170．10。配方胶料物理性能和成品性能达到GB／T13061－91标准要求。     

橡胶密封件的失效分析与橡胶断口形态

讨论了橡胶密封件的失效形式、失效原因及断口形态分析在失效分析中的作用。阐述了橡胶断口形态的一般特征、形成原因,探讨了老化失效对橡胶断口形态的影响。     

Lignin reinforced rubber composites

Lignin, a renewable waste material of pulp and paper industries, was analyzed through Fourier‐Transform Infrared Spectroscopy (FTIR) and found to be structurally similar to kraft lignin. Surface modification by addition of benzoyl peroxide and subsequent heating at 70°C caused generation of new functional groups in lignin. Efficacy of the crude lignin as well as that of the modified variety as a filler in nitrile rubber (NBR) has been evaluated. Rubber vulcanizates were analyzed for physico‐mechanical properties, oil and fuel resistance, and thermal stability, and compared with conventional fillers like phenolic resin and carbon black. Modified lignin has been found to produce superior elongation, hardness and compression set properties compared to phenolic resin but inferior to carbon black. Resistance to swelling, however, depends on the type of oil or fuel, and modified lignin always showed better properties than carbon black. Both thermo‐gravimetric analysis (TGA) and thermo‐mechanical analysis (TMA) showed highest thermal stability for the modified lignin followed by phenolic resin and carbon black.     

空气弹簧橡胶气囊配方的研究

介绍空气弹簧橡胶气囊胶料的配方设计及空气弹簧性能试验。确定的空气弹簧气囊胶料优化配方为：CR(牌号GRT) 100，氧化锌 5，氧化镁 4，促进剂 DM 硫黄 1．5，炭黑 30，软化剂 11．5，防老剂 4010NA／ODA 7，其它 5。该配方胶料的性能达到Contitech公司空气弹簧橡胶气囊胶料性能指标的要求。     

In situ dispersion and compatibilization of lignin/epoxidized natural rubber composites: reactivity,morphology and property

Lignin, a naturally occurring polymer, was viewed as a potential substitute of carbon black for reinforcing rubber materials. However, it shows no reinforcing effect if directly mixed with rubber. In this study, lignin was in situ dispersed at submicrometer size and highly compatible with epoxidized natural rubber (ENR) by using a high‐temperature dynamic heat treatment (HTDHT). Rheology analysis indicated that the ring opening reaction between lignin and ENR occurred at 160°C or above, which was further confirmed by infrared spectroscopy. Due to the consumption of acidic groups of lignin by ENR, the retardant vulcanization effect of lignin was weakened. Morphology observation and dynamic mechanical analysis demonstrated the perfect lignin dispersion and the strong interactions between lignin and ENR. The mechanical properties of the lignin/ENR composites were significantly improved by using HTDHT. Compared to the directly mixed rubber composites, the tensile strength and tear strength of the heat treated rubber composites filled with 40 phr lignin were increased by 114% and 23%, respectively. Especially, the 300% modulus of the heat treated rubber composite was increased by ca. 400%. X‐ray diffraction results indicated that the reinforcement of the composites originated from the presence of lignin rather than the strain‐induced crystallization of ENR. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42044.     

高性能氢化丁腈橡胶的配方与性能

在加氢度为96％、结合丙烯腈质量分数为34％的氢化丁腈橡胶(HNBR)中,以2,5-二甲基-2,5-双(叔丁基过氧基)己烷为硫化剂,三烯丙基异氰脲酸酯(TAIC)为助硫化剂,分别加入不同牌号的炭黑[N330,N539,N550,半补强炭黑(SRF)或喷雾炭黑],于180℃下硫化15min,制备了具有低压缩永久变形、优异力学性能的HNBR硫化胶。结果表明,增加硫化剂用量,以及在其较小用量下添加TAIC时,可降低HNBR硫化胶的压缩永久变形。对不同牌号炭黑增强硫化胶综合性能的分析可知,在硫化剂用量为6．25份(质量,下同),TAIC用量为1．25份时,炭黑对HNBR硫化胶增强效果由大到小为：N330,N539,N550,SRF,喷雾炭黑。     

Cryogenic microcracking of rubber toughened composites

This study investigated the influence of carboxyl‐terminated butadiene acrylonitrile (CTBN) liquid rubbers on the microcracking response of polymeric composite materials to cryogenic cycling. Matrices of carbon fiber/epoxy prepregs were modified with different concentrations of two CTBN liquid rubbers. The glass transition temperature and the interlaminar shear strength of the laminate systems were depressed as a result of the presence of CTBN in the epoxy phase. An increase in total rubber concentration with the continuous phase was found to decrease and in some cases eliminate microcracking in laminates exposed to cryogenic cycling.     

石墨烯基橡胶复合材料的制备与性能

综述了近年国内外石墨烯基橡胶复合材料的研究进展,主要包括石墨烯/天然橡胶复合材料、石墨烯/丁腈橡胶复合材料、石墨烯/丁苯橡胶复合材料、石墨烯/硅橡胶复合材料、石墨烯/丁基橡胶复合材料和石墨烯/异戊橡胶复合材料。同时对石墨烯基橡胶复合材料在制备和应用过程中遇到的难题进行了分析和总结。开发高质量石墨烯的绿色环保低成本制备和提纯技术以及提高石墨烯在橡胶中的有效分散效果将是今后该领域亟待解决的关键技术问题。     

Modification of rubber powder with peroxide and properties of polypropylene/rubber composites

Waste tire powder was functionalized in the presence of various concentrations of allylamine and benzoyl peroxide. Fourier transform infrared spectroscopy studies confirmed the presence of allylamine on the surface of the rubber powder. The surface energy of the functionalized rubber powder revealed that the introduction of allylamine onto the rubber powder surface increased the surface activity. Improvements in the tensile strength, elongation at break, and storage modulus were observed for polypropylene/modified rubber powder/maleic anhydride grafted polypropylene, and this was attributed to an improvement in the compatibility due to the chemical interaction between the rubber powder and compatibilizer. Evidence for the reaction between the rubber surface and compatibilizer was observed in Fourier transform infrared studies. This peroxide‐initiated monomer‐grafting technique is feasible for large‐scale processes. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 2237–2243, 2007     

Ultrasonic properties and morphology of devulcanized rubber blends

The ultrasonic properties of two devulcanized rubber (DR) blends with a styrene‐butadiene‐styrene (SBS) copolymer compound (ACE) are investigated using a transmission method. The DR materials are obtained from commercial rubber crumbs (RC) by a proprietary devulcanization technique. Measurements on the acoustic attenuation and travel velocity are conducted on the samples with different sample thicknesses in the pulsed mode. Attenuation coefficients of the materials are obtained by changing the frequency of the ultrasound in the tuned tone‐burst mode. The two DR/ACE blends show marked differences in the attenuation and attenuation coefficient, although the ultrasonic velocities are similar. These differences arise from the variation of the remaining degree of crosslinking in the DR materials. The acoustic velocities in the three materials are similar. The morphologies of the DR/ACE blend samples, observed using scanning electron microscopy (SEM) with different staining agents, explain their similarities and differences. There are two crops of rubber particles: larger ones belong to the original rubber crumbs that survived devulcanization; the smaller ones are fragments of partially DR. These crosslinked particles contribute to the overall degree of crosslinking in the blends. The devulcanized fractions of the DR materials are dispersed in the ACE matrix. Scattering at the interface accounts for the differences in the acoustic attenuation of the samples. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

石墨烯基橡胶复合材料的制备与性能

综述了近年国内外石墨烯基橡胶复合材料的研究进展,主要包括石墨烯/天然橡胶复合材料、石墨烯/丁腈橡胶复合材料、石墨烯/丁苯橡胶复合材料、石墨烯/硅橡胶复合材料、石墨烯/丁基橡胶复合材料和石墨烯/异戊橡胶复合材料。同时对石墨烯基橡胶复合材料在制备和应用过程中遇到的难题进行了分析和总结。开发高质量石墨烯的绿色环保低成本制备和提纯技术以及提高石墨烯在橡胶中的有效分散效果将是今后该领域亟待解决的关键技术问题。     

硅橡胶复合材料的制备及摩擦性能

考察了白炭黑、羟基硅油对硅橡胶复合材料摩擦性能的影响,研究了硅橡胶复合材料在干、湿光滑玻璃表面摩擦系数的影响因素及摩擦机理.结果表明,硅橡胶复合材料在光滑玻璃表面的干摩擦系数(fD)与损耗因子(tanδ)/邵尔A硬度(H)、tanδ/剪切储能模量(G')均呈线性正相关,随白炭黑用量的增加,fD降低.当增塑剂用量小于7....