Reinforcement of Styrene-Butadiene Rubber with Silica Modified by Silane Coupling Agents: Experimental and Theoretical Chemistry Study

The properties of styrene-butadiene rubber (SBR) reinforced by modified silica was investigated according to national standards. Silica was modified by silane coupling agents KH-570, KH-590, and KH-792. The optimized geome-tries of molecular modified silica reinforced SBR were obtained by using B3LYP calculation of density functional theory with the 6-31+G basis sets. The natural bond orbital analyses were carried out. The Si—O bond length of silica modified by KH-792 was the shortest and the electronegative of O was the highest. It indicated that the connection between silica and KH-792 was the tightest. Higher tensile strength and elongation of reinforced SBR was obtained by silica modified with the KH-792. It was caused by large delocalization of lone pair electrons of the two N atoms in KH-792. The S—C bond length in silica modified by KH-590 was longer than the ordinary S—C bond length. Then the sulfur free radical (·S·) was produced more easily in vulcanization. The degree of crosslink was increased by the cross-linkage of the rubber molecule and the sulfur free radical. That was why the highest stress and tear strength of reinforced SBR was produced when silane coupling agent KH-590 was used. The calculation results was in accord with experimental data.

MORPHOLOGY,INTERFACIAL INTERACTION AND PROPERTIES OF STYRENE-BUTADIENE RUBBER/MODIFIED HALLOYSITE NANOTUBE NANOCOMPOSITES

A natural nanotubular material,halloysite nanotubes(HNTs),was introduced to prepare styrene-butadiene rubber/modified halloysite nanotube(SBR/m-HNT) nanocomposites.Complex of resorcinol and hexamethylenetetramine (RH) was used as the interfacial modifier.The structure,morphology and mechanical properties of SBR/m-HNT nanocomposites,especially the interfacial interactions,were investigated.SEM and TEM observations showed that RH can not only facilitate the dispersion and orientation of HNTs in SBR matrix at ...

Oil Gels Based on Styrene Butadiene Rubber

Four oil absorbents based on styrene butadiene (SBR),i. e., pure SBR (PS), 4- tert-butylstyrene-SBR (PBS),EPDM-SBR network (PES) and 4-tert-butylstyrene-EPDMSBR ( PBES ), were produced from crosslinking polymerization of uncured styrene butadiene rubber (SBR),4- tert-butylstyrene ( tBS ) and ethylene-propylene-diene terpolymer (EPDM). The reaction took place in toluene using benzoyl peroxide (BPO) as an initiator. Uncured SBR was used as both a pre-polymer and a crosslink agent in this work, and the crosslinked polymer was identified by IR spectroscopy. The oil absorbency of the crosslinked polymer was evaluated with the method ASTM (F726 - 81). The order of maximum oil absorbency was PBES ＞ PBS ＞PES ＞ PS. The maximum values of oil absorbency of PBES and PBS were 74.0g/g and 69.5g/g, respectively. Gel fractions and swelling kinetic constants, however, had the opposite sequences. The swelling kinetic constant of PS evaluated by an experimental equation was 49. 97 ×10-2h-1.

Volatile Substances in Polymer Toys Made from Butadiene and Styrene

The residual levels and migration behavior of volatile substances were detected using HS-GC/MS for acrylonitrile-butadiene-styrene copolymer (ABS) toys, thermoplastic elastomer toys, and rubber toys made from 1,3-butadiene and styrene found on the Japanese market. The maximum residual level of these volatile substances was 2600 μg/g of styrene in ABS toys. In particular, the levels of known carcinogens 1,3-butadiene, benzene, and acrylonitrile are 5.3, 2.5 and 55 μg/g, which are much lower than the EU limit of 0.1%. Furthermore, some volatile substances migrated from ABS toys into water in amounts of 3 -40 ng/mL. Thermoplastic elastomer toys and rubber toys contained these volatile substances at significantly lower levels than ABS toys.

Synthesis and performance of miktoarm star copolymers of styrene and butadiene

A novel multifunctional macromolecular organolithium initiator （PD-Sn-（RLi）3） was prepared via living anionic polymerization and used for the synthesis of miktoarm star copolymers in cyclohexane. The average molecular weight, polydispersity index, microstructure and unit composition of the miktoarm star copolymers were characterized with GPC and 1H-NMR. Performances of the miktoarm star styrene-butadiene rubbers were investigated in comparison with those of the blend rubbers such as the tin-coupled star-shaped random copolymers of styrene-butadiene rubber（S-SBR）/natural rubber （NR） blend rubber and S-SBR/Cis-1, 4-polybutadiene rubber （Cis-BR） blend rubber.

基于响应曲面法的WER-SBR复合改性乳化沥青性能研究

为了定量分析水性环氧树脂(WER)和丁苯橡胶乳液(SBR)对乳化沥青性能的影响,并优化其配合比设计。基于响应曲面法设计了三因素三水平正交试验并以WER掺量、SBR掺量及固化温度为试验变量,以三大指标、车辙因子以及S/m值作为响应指标,利用Box-Behnken模型进行WER-SBR复合改性乳化沥青试验设计,并对试验结果进行回归分析。结果表明:WER能显著提高乳化沥青的高温性能,而低温性能的改善主要得益于SBR的低温柔韧性,固化温度对各响应指标的影响均呈现先增加后减小的变化趋势;当WER掺量为16%,SBR掺量为4%,固化温度为70℃时综合性能最优,其三大指标均满足规范值,高低温性能均优于单一改性乳化沥青和基质乳化沥青;实际试验值与预测值误差均不超过1%,表明改性剂掺量及固化条件可以利用响应曲面法进行设计、优化、预测,且结果具有一定的可靠度。

搅拌工艺对高掺量丁苯乳液改性硫铝酸盐水泥性能的影响

研究了搅拌速度与搅拌时间对高掺量丁苯乳液改性硫铝酸盐水泥砂浆的匀质性、含气量、流变性能、早期强度等宏观性能的影响,采用TGA、BET等微观手段研究了硬化砂浆的水化程度和孔隙特征。结果表明:延长搅拌时间、提高搅拌速率均可改善砂浆的匀质性和力学强度。但以176 r/min搅拌时,延长搅拌时间会提高新拌砂浆含气量,增大硬化砂浆“凝胶孔”含量,抑制水泥前1 h的水化。以108 r/min搅拌时,延长搅拌时间则促进水泥前1 h的水化。延长搅拌时间和提升搅拌速率阻碍砂浆絮凝,破坏水泥颗粒桥接,显著降低结构构筑速率。延长搅拌时间,砂浆屈服应力和塑性黏度降低。优化搅拌工艺,有助于为充填层修补砂浆的搅拌规范制定提供重要参数。

国产官能化溶聚丁苯橡胶BF2055M混炼胶性能研究

官能化溶聚丁苯橡胶(SSBR)在绿色高性能轮胎领域应用广泛,且牌号众多,选择三种在国内轮胎行业应用较多的进口官能化SSBR与国产官能化SSBR BF2055M进行综合性能比较。实验结果表明,SSBR BF2055M与进口SSBR相比,具有良好的白炭黑分散性、与白炭黑的亲和性、加工安全性,硫化速率快;硫化胶的定伸应力大、回弹性好、拉伸强度较高、压缩温升较低;具有更好的高抗湿滑性能和低滚动阻力性能的平衡性,能够给轮胎提供更好的驾驶安全性和节油性,适用于城市路面的四季胎。在胎面胶的配方开发上建议复配天然橡胶以提高硫化胶的耐磨性。

可替代胎面胶用乳聚丁苯橡胶的集成橡胶SIBR实用配方研究

研究了集成橡胶SIBR2505和SIBR2535的性能特点,压缩疲劳温升低,抗湿滑性能好和滚动阻力小,可分别代替乳聚丁苯橡胶ESBR1502和ESBR1712用作轮胎胎面胶中。针对集成橡胶性能特点进行轮胎实用配方研究,配方SIBR2535-1和SIBR2505-3具有较好的耐磨性和老化性能,适宜用作新能源车轮胎胎面胶;配方SIBR2535-2和SIBR2505-2具有较好的耐屈挠龟裂性能,配方SIBR2505-2和SIBR2505-3具有较好的耐刺扎性,适宜用作工程胎或农耕车胎胎面胶。配方SIBR2535-1、SIBR2535-2、SIBR2505-2和SIBR2505-3具有较高的抗湿滑性能和较低的滚动阻力,适宜用作绿色高性能轮胎胎面胶。

环保橡胶增塑剂RAE作橡胶填充油的性能研究

以环烷基减压渣油为原料,制备高芳碳含量的环保橡胶增塑剂RAE,将其与进口处理芳烃油进行对比研究。试验结果表明,RAE可作为填充油制备充油乳聚丁苯橡胶,充油丁苯橡胶的生胶性能、化学组成、结构组成等与使用进口处理芳烃油合成的充油丁苯橡胶性能相近;使用RAE制备的充油丁苯橡胶,在半钢胎胎面胶配方中,具有良好的混炼胶性能、硫化胶物理性能和动态力学性能。

Vulcanization Kinetics of Graphene/Styrene Butadiene Rubber Nanocomposites

This paper presents the influence of graphene on the vulcanization kinetics of styrene butadiene rubber （SBR） with dicumyl peroxide. A curemeter and a differential scanning calorimeter were used to investigate the cure kinetics, from which the kinetic parameters and apparent activation energy were obtained. It turns out that with increasing graphene loading, the induction period of the vulcanization process of SBR is remarkably reduced at low graphene loading and then levels off; on the other hand, the optimum cure time shows a monotonous decrease. As a result, the vulcanization rate is suppressed at first and then accelerated, and the corresponding activation energy increases slightly at first and then decreases. Upon adding graphene, the crosslinking density of the nanocomposites increases, because graphene takes part in the vulcanization process.

New Fabrication and Mechanical Properties of Styrene-Butadiene Rubber/Carbon Nanotubes Nanocomposite

A novel technology to prepare styrene-butadiene rubber （SBR）/carbon nanotubes （CNTs） composites was developed by combining a spray drying method and a subsequent mechanical mixing process. The cross-linking degrees of the vulcanized composites increased gradually with the additive CNTs contents. By comparing with those of the pure SBR composites, the mechanical properties such as tensile strength, tear strength and hardness of the composites filled with CNTs at certain contents were dramatically improved almost by 600%, 250% and 70%, respectively. The fabrication of the CNTs filled with SBR composites by combination of the spray drying method and subsequent mechanical mixing process was effective for enhancing the reinforcement effects of CNTs in rubbers. The novel technology can also open a new route for the modification and reinforcement on the nanocomposites with large amount of CNTs.

Microstructure characterization and thermal properties of the waste-styrene-butadiene-rubber (WSBR)-modified petroleum-based mesophase asphalt

In this work, waste-styrene-butadiene-rubber(WSBR)-modified petroleum-based mesophase asphalt was prepared through a co-carbonization process. The influence of contents of WSBR and carbonization temperature on the properties of mesophase asphalt was investigated. The chemical constituents,microstructure and thermal property of the samples were characterized. The results show that using WSBR as modifier can significantly promote the formation of mesophase. When the temperature is constant, the addition of WSBR results in more optically anisotropic crystal structure in the samples, and a better thermal stability. When the content of WSBR is invariable, with increasing temperature, the content of anisotropic structure in mesophase asphalt becomes higher and more uniform. The thermal stability of the samples is the best when WSBR content is 10 wt%.

硅负极黏结剂对锂离子电池性能的影响

为考察负极黏结剂对锂离子电池性能的影响,分别以丁苯橡胶(SBR)、改性SBR、苯乙烯丙烯酸酯(SA)为负极黏结剂,制备锂离子电池,并对电池的性能进行评估。SA黏结剂在内阻、低温放电及循环性能上优于传统的SBR黏结剂。在25℃下,SA黏结剂制备电池的直流内阻为28.68 mΩ,比SBR黏结剂制备的电池下降了22.08%;-20℃下则下降了26.26%。与SBR黏结剂制备的电池相比,在2.8~4.2 V充放电,SA黏结剂制备电池以1.0 C(2.3 A)放电,-20℃与25℃容量之比提高10.78个百分点;25℃下以2.2 C快充循环700次,容量保持率提高9.3个百分点。

国产环保型填充油在溶聚丁苯橡胶中的应用研究

考察了中国石化济南分公司200#环保型橡胶填充油作为溶聚丁苯橡胶(SSBR)填充油及加工过程操作油的应用效果,并与德国汉圣公司V500填充油进行对比实验,探讨了200#填充油替代V500填充油的可行性。实验结果表明,200#填充油赋予橡胶更低的混炼胶门尼黏度、略优的加工性能、较高的加工安全性和较快的硫化速率,更优的动态性能,抗湿滑性提高9%,滚动阻力降低6%。200#填充油在SSBR中的应用效果略优于V500填充油,完全满足高性能SSBR使用要求。

EPDM-g-LSBR的制备及其增容EPDM/SBR并用橡胶的性能研究

采用熔融密炼接枝工艺,以三元乙丙橡胶(EPDM)为基体,低分子量液体丁苯橡胶(LSBR)为接枝物,制备了接枝聚合物EPDM-g-LSBR,研究了制备条件对接枝聚合物红外光谱和热失重行为的影响;将EPDM-g-LSBR作为相容剂用于EPDM/SBR的增容性共混,并与常用的商业化嵌段聚合物乙烯-乙酸乙烯酯(EVM)和苯乙烯-乙烯-丙烯-苯乙烯嵌段共聚物(SEPS)的增容效果进行了对比,研究了其用量对并用胶硫化特性和硫化胶力学性能的影响。结果表明,LSBR接枝到EPDM分子主链上,接枝量的变化未对产物的热降解温度造成显著影响;接枝物EPDM-g-LSBR增容后EPDM/SBR并用胶力学性能有明显改善,添加8份时,材料的拉伸强度和断裂伸长率比未添加相容剂的体系提高了24.3%和15%,邵A硬度由未添加的75.4降低到72.6。通过对混炼胶的断面进行扫描电镜分析发现EPDM-g-LSBR的加入使EPDM在SBR中的海岛分散结构消失,增加了两相的相容性。

环氧化溶聚丁苯橡胶改性的溶聚丁苯橡胶/白炭黑复合材料的性能

将环氧度为15%的环氧化溶聚丁苯橡胶作为改性剂,研究了环氧化溶聚丁苯橡胶对溶聚丁苯橡胶/白炭黑复合材料的加工性能、物理机械性能、动态力学性能及白炭黑分散性等的影响。结果表明,环氧化溶聚丁苯橡胶的加入减缓了复合材料的硫化速率,混炼胶中的结合胶含量增大;溶聚丁苯橡胶/白炭黑硫化胶的定伸应力、耐磨性及回弹性能提高,压缩生热降低,同时硫化胶的抗湿滑性能得到提升、滚动阻力下降。

用巯基-烯点击法制备1,2-聚丁二烯包覆的白炭黑及其对丁苯橡胶的增强

采用巯基-烯点击法制备出1,2-聚丁二烯包覆的疏水性白炭黑(Silica-PBs)。红外光谱和X射线电子能谱分析表明,Silica-PBs表面被1,2-聚丁二烯所包覆,并且还有多余的乙烯基。将Silica-PBs与丁苯橡胶(SBR)共混制备的硫化胶相比于使用硅烷偶联剂改性制得的硫化胶具有更优异的综合性能。通过橡胶加工分析仪和电子显微镜分析均可以发现,Silica-PBs在SBR中具有更好的分散状态。Silica-PBs可以在填料与橡胶分子链之间形成一条“缓冲带”,为填料在橡胶分子链滑移时提供一定的缓冲作用。动态力学性能测试结果显示,Silica-PBs相比于传统白炭黑提高SBR/Silica-PBs复合材料的动态力学性能8%以上,可以作为一种理想的绿色轮胎用填料。

高耐磨导静电石墨烯杂化材料/丁苯/顺丁胎面胶的研制

采用单宁酸辅助液相剥离所制备的石墨烯,获得了比普通石墨烯更好的分散性,可以达到低成本、高产量和环保的要求。用硅烷偶联剂(KH550)改性处理的SiO_(2)和单宁酸修饰的石墨烯发生反应形成强杂化键,成功得到石墨烯-SiO_(2)杂化材料。研究了石墨烯-SiO_(2)杂化材料在丁苯/顺丁橡胶复合材料中的力学性能,同时还研究了将导电炭黑与石墨烯-SiO_(2)杂化材料共混后在丁苯/顺丁橡胶复合材料中的力学性能以及导电导热性能。结果表明:加入1份石墨烯-SiO_(2)杂化材料时,丁苯/顺丁橡胶复合材料获得了相对良好的耐磨性;如果负载超过1份,石墨烯填料之间会很容易发生再聚集,导致磨损体积相比于空白对照组有所增加;加入8份自制石墨烯时,电阻值降低至2×10^(6)Ω,橡胶复合材料的抗静电性能得到了明显的改善。

水性环氧-SBR乳化沥青微表处混合料路用性能研究

以水性环氧树脂(WER)和丁苯(SBR)胶乳为乳化沥青改性剂,制备水性环氧-SBR乳化沥青(WESEA),采用蒸发残留物三大指标、旋转黏度、水煮法、湿轮磨耗试验、冻融循环试验、轮辙变形试验,探究水性环氧掺量对WESEA胶结料及其微表处混合料路用性能的影响。结果表明:WESEA胶结料高温性能、黏度与黏附性均随着水性环氧掺量增加而提升;当水性环氧掺量为10%时,WESEA微表处混合料1h湿轮磨耗值、6d湿轮磨耗值分别较SBR改性乳化沥青微表处混合料降低50.2%、44.0%,宽度变形率降低了41.8%;WESEA微表处混合料的耐磨性、抗水损能力以及抗车辙性能均优于SBR改性乳化沥青微表处混合料。