纳米三氧化二铝增强天然橡胶/丁苯橡胶并用胶的性能

采用机械混炼法制备了纳米三氧化二铝(Al_2O_3)增强天然橡胶(NR)/丁苯橡胶(SBR)并用胶,研究了纳米Al_2O_3对NR/SBR并用胶的硫化特性、力学性能、耐热性和耐溶剂性的影响。结果表明,当纳米Al_2O_3的用量为4份,并采用NR/SBR与小料共混均匀后再加入纳米与硫黄的方式制备NR/SBR并用胶,可大幅提高NR/SBR并用胶的力学性能。与未增强并用胶相比,采用4份纳米Al_2O_3增强并用胶的100%定伸应力、拉伸强度、撕裂强度和扯断伸长率分别提高了16.0%、296.4%、28.6%和73.3%,耐热性及耐油性也得到显著提高。     

纳米碳酸钙/二氧化硅复合粒子对丁苯橡胶物理机械性能的影响

采用溶胶沉淀法制备了纳米CaCO3/SiO2复合粒子,并用不同改性剂对其进行表面改性,考察了改性复合粒子对丁苯橡胶(SBR)物理机械性能的影响,同时与硬脂酸钠改性纳米CaCO3填充的SBR硫化胶做了比较。结果表明,CaCO3/SiO2复合粒子粒径为40～50 nm,大小均匀,表面粗糙,SiO2包覆在纳米CaCO3表面,具有核壳结构;硬脂酸钠改性复合粒子填充SBR硫化胶的拉伸强度、撕裂强度、永久变形和邵尔A硬度均大于改性纳米CaCO3填充SBR硫化胶,最大拉伸强度可达到13.6 MPa,两者的300%定伸应力和扯断伸长率相当;用硬脂酸钠和Si 69协同改性的纳米CaCO3/SiO2填充SBR硫化胶的拉伸强度、300%定伸应力、撕裂强度和邵尔A硬度均明显优于硬脂酸钠改性复合粒子填充的SBR硫化胶,最大拉伸强度达到14.1 MPa,扯断伸长率减小,低填充量时两者的永久变形差别不大,高填充量时前者的永久变形低于后者。     

掺杂氧化钐的炭黑用量对粉末天然橡胶性能的影响

高耐磨炉黑(HAF)填充型粉末天然橡胶(NR)[P(NR/HAF)]硫化胶的缺点是300%定伸应力低,因此,采用Sm2O3掺杂HAF(HAF-Sm),用凝聚共沉法制备了掺杂Sm2O3的HAF填充型粉末天然橡胶(NR)[P(NR/HAF-Sm)],研究了其硫化胶的力学性能与Sm2O3及HAF用量之间的关系。结果表明:在炭黑用量为10~100份,当炭黑用量相同、Sm2O3的质量分数为HAF的3%时,其P(NR/HAF-Sm)硫化胶的300%定伸应力显著高于P(NR/HAF)硫化胶,而与块状NR(MNR)/HAF机械混炼胶料硫化胶的相近;其拉伸强度、100%定伸应力和撕裂强度明显高于P(NR/HAF)及MNR/HAF硫化胶。这说明适量的Sm2O3掺杂HAF可显著提高炭黑填充型粉末NR硫化胶的300%定伸应力及其他力学性能。     

石墨烯/橡胶复合材料在输送带胶料中的应用

研究石墨烯/丁苯橡胶(SBR)复合材料或石墨烯/天然橡胶(NR)复合材料在输送带胶料中的应用。结果表明:添加石墨烯可以显著提高SBR胶料和NR/SBR胶料的300%定伸应力、拉伸强度、撕裂强度和耐磨性能;石墨烯/SBR复合母胶或石墨烯/NR复合母胶(石墨烯质量分数为0. 1)用量为10～15份时,胶料的加工安全性、物理性能、耐磨性能和耐热老化性能较好;添加少量石墨烯即可提高输送带胶料的抗撕裂性能和耐磨性能,有利于延长输送带的使用寿命。     

超细全硫化粉末丁苯橡胶/纳米碳酸钙复合粉末对丁苯橡胶性能的影响

采用超细全硫化粉末丁苯橡胶(UFPSBR)/纳米碳酸钙复合粉末制备UFPSBR/纳米碳酸钙/丁苯橡胶(SBR)纳米复合材料,并对其性能进行研究。结果表明:随着UFPSBR/纳米碳酸钙复合粉末用量的增大,UFPSBR/纳米碳酸钙/SBR纳米复合材料的硫化时间缩短、硫化速率加快、物理性能和阻燃性能提高,同时玻璃化温度下降、储能模量增大。     

石墨烯和碳纳米管的天然橡胶纳米复合材料性能的研究

采用湿法混炼工艺制备石墨烯/天然橡胶（NR）纳米复合材料和碳纳米管/NR纳米复合材料,研究石墨烯和碳纳米管用量对NR纳米复合材料性能的影响。结果表明：随着石墨烯和碳纳米管用量的增大,NR纳米复合材料的热导率和比热容均先增大后减小;石墨烯/NR纳米复合材料的300%定伸应力先减小后增大,石墨烯用量为2份的石墨烯/NR纳米复合材料的拉断伸长率最大;碳纳米管/NR纳米复合材料的300%定伸应力增大,碳纳米管用量为3份的碳纳米管/NR纳米复合材料的撕裂强度最大。随着温度的升高,石墨烯/NR纳米复合材料的相对介电常数呈先增大后减小的趋势,在110℃时最大;碳纳米管/NR纳米复合材料的相对介电常数呈增大的趋势。     

聚氨酯/纳米金刚石纳米复合材料的性能研究

通过原位反应法制备了聚氨酯(PU)/纳米金刚石(ND)纳米复合材料,采用X射线衍射(XRD)、热失重分析(TGA)、扫描电子显微镜(SEM)和力学性能测试等手段系统研究了PU/ND纳米复合材料的力学性能、热性能和形态。研究结果表明,ND能够显著提高聚氨酯的力学性能。随着ND用量的增加,PU/ND纳米复合材料的拉伸强度、100%定伸应力、500%定伸应力和断裂伸长率先增加后减少。当ND质量分数为0.5%时,PU/ND纳米复合材料的力学性能最佳,拉伸强度和断裂伸长率分别提高了61.5%和39.1%。PU/ND纳米复合材料的T-剥离强度和耐热性也有提高。     

片层钠基蒙脱土调控炭黑对天然橡胶/丁苯橡胶纳米复合材料性能的影响

采用乳液共混法先制备天然橡胶(NR)/片层钠基蒙脱土(Na-MMT)、丁苯橡胶(SBR)/Na-MMT和NR/SBR/Na-MMT母胶,再制备得到相应的NR/SBR/Na-MMT纳米复合材料,研究Na-MMT对NR/SBR/Na-MMT纳米复合材料的微观形貌、物理性能和耐磨性能的影响。结果表明：采用NR/Na-MMT母胶共混法制备的NR/SBR/Na-MMT纳米复合材料中Na-MMT的分散效果最好,剥离状态的Na-MMT占比最大,炭黑的分散明显改善,片层Na-MMT可在一定程度上调控炭黑在NR/SBR/Na-MMT纳米复合材料中的偏析行为;该橡胶纳米复合材料的定伸应力、拉伸强度和拉断伸长率最大,阿克隆磨耗量最小(0.177 cm³),磨耗表面沟壑最浅,耐磨性能最佳。     

两种橡胶/有机累托石纳米复合材料的结构与性能

比较了用熔体法制备的有机累托石(OR)/丁苯橡胶(SBR)以及有机累托石(OR)/天然橡胶(NR)2种纳米复合材料的结构与性能.TEM和XRD对材料的分析显示,由于橡胶基体的性质差异,OR/SBR为典型的插层型结构,而OR/NR为插层型和部分剥离型混合结构.应力应变行为的研究表明,随着OR用量的增加,OR/SBR的拉伸强度和拉断伸长率均增大,这主要是分子链滑移和填料的取向造成的.对于拉伸结晶型橡胶NR,由于部分剥离型填料的增强作用,NR的定伸应力随填料用量的增加而逐渐提高.由于对结晶的阻碍作用,当OR用量为20份时,OR/NR的拉伸强度有所降低.纳米累托石的加入可以显著提高SBR和NR的硬度和撕裂强度.热失重分析表明,OR/橡胶纳米复合材料与相应的纯橡胶相比,热稳定性提高,在NR体系中更为显著.     

纳米氧化锌对NR/BR胎面胶性能的影响

试验研究纳米氧化锌对不同并用比NR/BR并用胶性能的影响及其减量替代间接法氧化锌在载重轮胎胎面胶中的应用。结果表明,以纳米氧化锌等量替代间接法氧化锌用于不同并用比NR/BR并用胶中,胶料的t10和t90延长,且随着BR用量的增大,延迟时间进一步延长;硫化胶的300%定伸应力、拉断强度和回弹值增大,二者300%定伸应力和拉断强度的差值随着NR/BR并用比的变化而无明显变化,回弹值的差值随着BR用量的增大而增大;抗撕裂性能和耐疲劳性能下降;以纳米氧化锌减量25%替代间接法氧化锌用于NR/BR(并用比60/40)胎面胶中,可改善胶料的加工安全性,降低生热,提高老化后性能,成品轮胎的耐久性能有所提高。     

Fly‐ash particles and precipitated silica as fillers in rubbers. II. Effects of silica content and Si69‐treatment in natural rubber/styrene–butadiene rubber vulcanizates

This article explored the possibility of using silica from fly‐ash particles as reinforcement in natural rubber/styrene–butadiene rubber (NR/SBR) vulcanizates. For a given silica content, the NR : SBR blend ratio of 1 : 1 (or 50 : 50 phr) exhibited the optimum mechanical properties for fly‐ash filled NR/SBR blend system. When using untreated silica from fly‐ash, the cure time and mechanical properties of the NR/SBR vulcanizates decreased with increasing silica content. The improvement of the mechanical properties was achieved by addition of Si69, the recommended dosage being 2.0 wt % of silica content. The optimum tensile strength of the silica filled NR/SBR vulcanizates was peaked at 10–20 phr silica contents. Most mechanical properties increased with thermal ageing. The addition of silica from fly‐ash in the NR/SBR vulcanizates was found to improve the elastic behavior, including compression set and resilience, as compared with that of commercial precipitated silica. Taking mechanical properties into account, the recommended dosage for the silica (FASi) content was 20 phr. For more effective reinforcement, the silica from fly‐ash particles had to be chemically treated with 2.0 wt % Si69. It was convincing that silica from fly‐ash particles could be used to replace commercial silica as reinforcement in NR/SBR vulcanizates for cost‐saving and environment benefits. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007     

纳米高岭土/橡胶复合材料的性能研究

研究纳米高岭土／橡胶（SBR，NR，BR和EPDM）复合材料的物理性能和热稳定性能，并用透射电子显微镜、X射线衍射、红外光谱和热重分析法对高岭土／橡胶复合材料进行分析。结果表明，与白炭黑／橡胶复合材料相比，纳米高岭土／橡胶复合材料回弹性、拉伸性能和热稳定性较好，撕裂强度和定伸应力稍差；高岭土片层厚度为纳米级、分散性良好、片状粒子与橡胶大分子在纳米尺度紧密结合以及纳米高岭土片层在橡胶基体中分离且定向平行排列，是复合材料具有优良物理性能和热稳定性的重要原因。     

纳米碳酸钙在NR/BR/SBR并用胶中的应用研究

采用带有酚醛基的反应性有机改性剂对纳米碳酸钙CCR进行改性制得M-CCR,并制备了NR/BR/SBR/CCR和NR/BR/SBR/M-CCR复合材料,研究了两种复合材料的微观形态以及力学性能和加工性能。结果表明,M-CCR在并用胶中的分散性优于CCR,对并用胶力学性能的提高更显著;两种填料都能改善并用胶的加工性能,并且不影响并用胶的抗湿滑性和滚动阻力。     

Organomodified montmorillonite as filler in natural and synthetic rubber

The filler action of dodecylamine (12C) intercalated montmorillonite (MNT) referred to as organomodified montmorillonite (12C‐MNT) up to 4 wt % on natural rubber (NR) and styrene butadiene rubber (SBR) was studied and findings were compared with respect to the unmodified Na‐MNT. X‐ray analysis was used to calculate the interchain separation (R and R′), degree of crystallinity (X_c), and distortion factor (k). It is noted that R and R′ showed the opposite trend, whereas X_c as well as k showed overall increasing trend with an increasing amount of 12C‐MNT on both NR and SBR. For Na‐MNT (1 wt %) filled NR and SBR, the corresponding magnitude of R and R ′ and X_c showed nearly no change, whereas k_c increased significantly. The crosslinking density (v_c) does not show any significant changes in NR, whereas for SBR, it increases with increasing 12C‐MNT as filler. Interestingly, in the case of 1 wt % pure Na‐MNT used as filler for both NR and SBR, v_c was lower compared to the virgin rubbers. Both swelling index (s_i) and sol fraction (Q) do not show any significant variation for NR composites, whereas these decrease for SBR composites with increasing concentration of 12C‐MNT filler. On the contrary, NR and SBR with 1 wt % of Na‐MNT filler show greater magnitude of s_i and Q corresponding to the pure ones. Measurements of mechanical properties showed a significant increase in tensile strength and elongation at break for NR‐12C‐MNT (4 wt %) when compared with either virgin NR. In addition, modulus at the elongation at 100 and 200% in general increases with increasing loading of 12C‐MNT filler in NR. Similar observations were also noted in the case of SBR. Interestingly, when only pure Na‐MNT is used as filler, the strength of NR and SBR decreases drastically. Scanning electron microscopic studies were also to used support the mechanical behavior of NR‐12MNT and SBR‐12CMNT composites. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 3583–3592, 2004     

机械共混法制备NR/SBR/OMMT纳米复合材料及其性能

选择不同牌号的有机蒙脱土（OMMT）,利用机械共混法制备了NR/SBR/OMMT纳米复合材料。测试了复合材料的力学性能,选择出了最佳牌号OMMT。不同含量的OMMT与共混胶复合后力学性能的测试结果表明：当OMMT含量仅为3份时,拉伸强度和断裂强度分别提高了90％和63%;利用X射线衍射和透射电子显微镜研究了复合材料的亚微观结构,观察结果显示制备出了分散均匀的剥离型NR/SBR/OMMT纳米复合材料,同时OMMT在轮船工业配方中的优异性能预示其良好的应用前景。     

Physicochemical characterization of the filler–matrix interface in elastomer‐encapsulated fly ash/polyester particulate composites

An attempt was made to improve the toughness of fly ash (FA)/general‐purpose unsaturated polyester resin (GPR) composites. Elastomer [styrene–butadiene rubber (SBR) or acrylic copolymer (AC)]‐encapsulated fillers (FA or CaCO₃) were made through the coagulation of the emulsified elastomer containing the filler with constant stirring. The elastomer‐encapsulated fillers were added to GPR at concentrations as high as 15 wt % to make FA/SBR or AC/GPR composites. The mechanical properties (i.e., the tensile strength, tensile modulus, tensile elongation, flexural strength, flexural modulus, impact strength, and hardness) of FA/GPR, FA/SBR/GPR, and FA/AC/GPR composites were studied. The tensile‐fractured surfaces of all the composites were studied with scanning electron microscopy. The thermal stability was studied with thermogravimetric analysis. An analysis of the results indicate that this modification technique is rather easy and more economical than the chemical modification of filler surfaces with functional silane coupling agents. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 171–184, 2005     

Preparation,characterization, and application of NR/SBR/Organoclay nanocomposites in the tire industry

The natural rubber/styrene butadiene rubber/organoclay (NR/SBR/organoclay) nanocomposites were successfully prepared with different types of organoclay by direct compounding. The optimal type of organoclay was selected by the mechanical properties characterization of the NR/SBR/organoclay composites. The series of NR/SBR/organoclay (the optimal organoclay) nanocomposites were prepared with various organoclay contents loading from 1.0 to 7.0 parts per hundreds of rubber (phr). The nearly completely exfoliated organoclay nanocomposites with uniform dispersion were confirmed by transmission electron microscopy (TEM) and X‐ray diffraction (XRD). The results of mechanical properties measurement showed that the tensile strength, tensile modulus, and tear strength were improved significantly when the organoclay content was less than 5.0 phr. The tensile strength and the tear strength of the nanocomposite with only 3.0 phr organoclay were improved by 92.8% and 63.4%, respectively. It showed organoclay has excellent reinforcement effect with low content. The reduction of the score and cure times of the composites indicated that the organoclay acted as accelerator in the process of vulcanization. The incorporation of a small amount of organoclay greatly improved the swelling behavior and thermal stability, which was attributed to the good barrier properties of the dispersed organoclay layers. The outstanding performance of co‐reinforcement system with organoclay in the tire formulation showed that the organoclay had a good application prospect in the tire industry, especially for the improvement of abrasion resistance and the reduction of production cost. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Mechanical and morphological properties of cellular NR/SBR vulcanizates under thermal and weathering ageing

The effects of addition of two chemical blowing agents in cellular rubber blend of natural rubber (NR) and styrene‐butadiene rubber (SBR) at a fixed blend ratio of 1 : 1 on cure characteristics, and mechanical and morphological properties were invesigated. The chemical blowing agents used in this work were Oxybis (benzene sulfonyl) hydrazide (OBSH) and Azo dicarbonamide (ADC). Three different fillers, fly ash (FA) particles, precipitated silica, carbon black (CB) at their optimum concentrations of 40 phr were used, the FA and silica particles being chemically treated by bis‐(3‐triethoxysilylpropyl) tetrasulphide. The results suggested that the overall cure time decreased with OBSH and ADC contents. The OBSH was more effective in cure‐acceleration of the NR/SBR blend than the ADC. The NR/SBR vulcanized foams produced by OBSH and ADC agents had closed‐cell structures. The specific density and mechanical properties of the blend tended to decrease with increasing blowing agent content. The CB gave NR/SBR foams with smaller cell size, better cell dispersion, and higher mechanical properties than the precipitated silica and FA particles. The heat ageing and weathering resulted in an increase in tensile modulus and hardness, but lowered the tensile strength, ultimate elongation and tear strength. The elastic recovery for cellular NR/SBR vulcanizates with FA was superior to that with CB and silica, the elastic recovery of the blends decreasing with blowing agent content. Resilience property was improved by the presence of gas phases. The optimum concentration of OBSH and ADC to be used for NR/SBR vulcanizates was 4 phr. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009