多聚磷酸与丁苯橡胶复配改性沥青的性能

研究了多聚磷酸与丁苯橡胶复配改性剂对沥青的热稳定性、动态力学性能、黏度及低温抗裂性能的影响.结果表明,多聚磷酸的加入能够提高沥青的黏度,改善沥青的高温抗车辙性能;丁苯橡胶的加入提高了沥青的黏度和低温抗裂性能,但对沥青的高温抗车辙能力有一定的负面影响;使用少量交联剂可提高沥青的高温抗车辙性能,降低其黏度.综合考虑沥青的高低温性能,宜以添加2份(质量,下同)多聚磷酸、6份丁苯橡胶及0.04份硫黄为最佳改性剂配方.     

在不同条件下用丁苯橡胶共混改性沥青的性能

选用2种具有典型组成的基质沥青,以丁苯橡胶为主改性剂对其进行反应共混改性,研究了不同改性条件对沥青组成变化及性能的影响.结果表明,单纯的硫化交联共混改性对沥青组成及改性效果影响不大,交联主要是与芳香烃中的活性基团进行的;在体系中加入稳定剂有利于提高改性沥青的针入度和低温延度;多聚磷酸对于交联的促进作用明显优于柠檬酸,改...     

Methacrylate-functionalized POSS influence on cross-linking and mechanical properties of styrene-butadiene rubber

Iranian Polymer Journal - The addition of methacrylate-functional polyhedral oligomeric silsesquioxane (MA-POSS) nanoparticles to styrene-butadiene rubber (SBR) composites was evaluated in terms of...     

Direct cleavage of internal epoxides with periodic acid

Reaction of methyl esters of epoxidized fatty acids with paraperiodic acid led to direct cleavage of epoxide functions and the production of aldehydes and methyl azelaaldehydate. The reaction was carried out in aqueous dioxane. The use of other solvents and the influence of reaction variables was examined. The reaction is essentially quantitative for methyl, 9,10-epoxystearate. Presented at the AOCS Meeting in Cineinnati, October 1965. E. Utiliz. Res. Dev. Div., ARS, USDA.     

判断橡胶油对丁苯橡胶性能影响的参数选择

针对环保型油品取代高芳烃油后,充油橡胶的性能不可避免地会有所变化的情况,总结了橡胶油参数对橡胶性能影响的传统认识。在炭黑包容胶理论的基础上,对判断影响丁苯橡胶性能的参数选择进行了推想,认为橡胶油的密度可以作为填充不同油品胶料性能变化的判断依据,并且借助一些试验数据进行了验证。     

超细全硫化粉末丁苯橡胶改性沥青的性能及相容剂的影响

采用低温高剪切改性工艺,用超细全硫化粉末丁笨橡胶(UFPSBR)对沥青进行改性,研究了UFPSBR的加入量和相容剂对沥青基本性能和动态力学性能的影响以及改性沥青的微现形貌.结果表明,随着UFPSBR掺入量的增加,改性沥青的软化点升高,25℃针入度减小,5℃延度提高,弹性模量和损耗模量都明显增大.相容剂的加入增强了UFP...     

Investigation and improvement of the scorch behavior of silica-filled solution styrene-butadiene rubber compound

Effects of different silane coupling agents on scorch time of silica-filled solution styrene-butadiene rubber compounds were studied. The flocculation of silica at high temperature, which was characterized by rubber processing analyzer (RPA) and transmission electron microscope (TEM), has been proved to be an important factor affecting the scorch time of the compounds. In order to prolong the scorch time, the hybrid silane technology, that is, combining different silanes such as bis(triethoxysilypropyl)-tetrasulfide (TESPT) and n-octyltriethoxysilane (OTES) together, was developed to improve silica dispersion and suppress silica flocculation. The results showed that when the content of TESPT is fixed, the increase of OTES can effectively increase the scorch time due to the suppression of silica flocculation while not affecting the polymer crosslinking. This phenomenon is absent for the case where the OTES content is fixed, but the TESPT content is varied because the sulfur atoms in the TESPT molecules will also participate in the vulcanization process, leading to the decrease in scorch time. Through the present study, a connection between silica flocculation and scorch time has been built up, which is important for rubber composite processing. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47918.     

Crosslinking of styrene-butadiene rubber with polyurethanes bicapped with benzyocyclobutene

Summary A polyurethane prepared from 1,9-nonanediol and toluene-2,4-diisocyanate with M_n=11,840, was capped on both ends in a reaction with 4-(benzocyclobutenyl) methanol. The polyurethane was used to crosslink styrene-butadiene rubber through Diels-Alder reactions on the benzocyclobutene functionality. The synthesis and characterization of 4-(benzocyclobutenyl) methanol, a molecule not reported previously, is presented. The crosslinking reaction was carried out on intimate mixtures of the telechelic polyurethane and SBR at elevated temperature and pressure. Various physical properties of the crosslinked material were studied.Work done at the Department of Chemistry, University of Akron, Akron, OH 44325, USA     

无卤阻燃剂的协同效应及对丁苯橡胶热失重行为的影响

将P-N型膨胀阻燃剂(IFR)、无机阻燃剂[Al(OH)3/P]与丁苯橡胶(SBR)共混制备无卤复合阻燃材料,研究了IFR与Al(OH)3/P阻燃SBR的协同效应和阻燃SBR的热失重行为。结果表明,IFR/Al(OH)3/P协同阻燃SBR,复合材料的极限氧指数达到29%,UL-94达到V-0级,热释放速率明显下降,IFR和Al(OH)3/P二者具有协同作用;在空气气氛下,IFR与Al(OH)3/P具有相互成炭作用。     

双硅氧烷端基溶聚丁苯橡胶的合成

采用负离子聚合方法,以环己烷-己烷为溶剂、四氢呋喃为结构调解剂、双锂为引发剂进行丁二烯-苯乙烯共聚,聚合结束后加入r-氯丙基三甲氧基硅烷进行封端,得到双硅氧烷端基的溶聚丁苯橡胶(SSBR),并用核磁共振对其进行了表征.结果表明,所合成的产物为双硅氧烷端基SSBR;并通过核磁共振谱图计算了不同相对分子质量的SSBR的封端效率.     

多聚磷酸/丁苯橡胶复合改性沥青的抗紫外老化性能

通过动态剪切流变试验、四组分试验和红外光谱测试沥青中的组分胶体指数差值和官能团结构指数,考察了分别由多聚磷酸(PPA)、丁苯橡胶(SBR)及SBR/PPA复合物改性沥青的抗紫外老化性能,探讨了老化的机理。结果表明,PPA的添加有效改善了沥青的高温流变性能,改性沥青的抗车辙因子和相位角的变化幅度较小。PPA或SBR/PPA复合改性沥青在紫外老化前后的胶体指数差值较小,而后者羧基和亚砜基指数的增大幅度要小于前者,丁二烯基指数的减小幅度小于SBR改性沥青。综合来看,PPA/SBR复合改性沥青的抗紫外老化性能优于基质沥青和PPA或SBR改性沥青。     

溶聚丁苯橡胶发展状况分析

介绍了溶聚丁苯橡胶的生产现状及技术进展,综述了世界备大橡胶公司的单釜连续聚合和多釜串联连续聚合工艺,分析了溶聚丁苯橡胶技术发展趋势及我国溶聚丁苯橡胶装置状况,提出了我国溶聚丁苯橡胶的发展建议.     

环保型填充油的乳化工艺及对丁苯橡胶充油效果的影响

以高门尼黏度丁苯橡胶(SBR)1723基础胶浆和稠环芳烃质量分数低于3.0%的环保型橡胶填充油为原料制备环保型充油SBR,考察了乳化工艺对填充油乳化效果的影响以及所制得的环保型充油SBR的性能。结果表明,在以歧化松香酸钾皂为乳化剂、先将乳化剂加入填充油中搅拌一段时间后再加入水的油乳化方式、油乳化温度为70℃、填充油/水/乳化剂(质量比)为100/200/2以及凝聚时搅拌转速为163 r/min、凝聚温度为65～70℃的条件下,所得产品的各项性能指标满足产品标准的要求。     

聚四氟乙烯改性乳聚丁苯橡胶性能研究

选取聚四氟乙烯(PTFE)分散液,采用乳液共沉法,研究其对乳聚丁苯橡胶(ESBR)性能的影响。结果表明,PTFE分散液的加入,提高了ESBR的耐油性,且其耐油性与PTFE分散液含量基本呈正比关系。此外,共混体系的力学性能也有一定改善。对于丁苯橡胶(SBR)/PTFE体系:共混比为90/10时,硬度增幅最大;在共混比为80/20时,拉伸强度达到最大值。扯断伸长率随着体系PTFE含量的增加,呈递减趋势。综合考虑,当PTFE质量份为10~20时,胶料耐焦烧性好,加工安全性较高,性能最优。     

双金属稀土促进剂对丁苯橡胶/天然橡胶胎面胶的影响

通过配位反应制备得到双金属硫化促进剂二乙基二硫代氨基甲酸锌镧配合物(ZnLaDC),在不添加传统活化体系氧化锌(ZnO)/硬脂酸(SA)的情况下,考察了ZnLaDC用量对丁苯橡胶(SBR)/天然橡胶(NR)胎面胶复合材料硫化特性及物理机械性能的影响,并与传统硫化体系二乙基二硫代氨基甲酸锌(ZnDC)/ZnO/SA制备的硫化胶性能进行了对比。结果表明,随着ZnLaDC用量的增加,SBR/NR胎面胶复合材料的硫化特性、压缩疲劳生热性能及耐磨性得到有效提高,当ZnLaDC用量为5份时,复合材料的综合性能最佳。与传统硫化体系ZnDC/ZnO/SA制备的硫化胶相比,采用ZnLaDC制备的硫化胶具有更优异的静态力学性能及耐切割性。     

Effect of ultrasonic extrusion of star styrene-butadiene rubber on properties of carbon black- and silica-filled compounds and vulcanizates

Extrusion of star styrene-butadiene rubber (SBR) without and with ultrasonic treatment at amplitudes 3.5, 5, 7.5, and 10 μm was carried out. The molecular structure of untreated and treated star SBR was determined. Significant reduction of die pressure was observed during ultrasonic treatment due to the thixotropic and degradation effects. Ultrasonic treatment of star SBR at 3.5 μm created molecules of higher molecular weight via long-chain branching without gel formation. Ultrasonic treatment of star SBR at 5 μm created a small amount of gel. At high ultrasonic amplitudes more gel was generated hindering mixing of star SBR with silica. Extruded star SBR was compounded with carbon black and precipitated silica, with and without silane. It was found that the long-chain branching induced by ultrasonic treatment improved the rubber–filler interaction in precipitated silica without silane, as confirmed by the increase of bound rubber content. The filler–filler interaction was reduced in silica compounds without silane, as indicated by study of Payne effect. The significantly improved rubber–filler interaction and reduced filler–filler interaction led to an increase of the modulus at 100% elongation and tensile strength of SBR/silica vulcanizates. Extensive comparisons were made with earlier study on ultrasonic treatment of linear SBR. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47451.     

Effects of silane coupling agents on mica-filled styrene-butadiene rubber

The effects of silane coupling agents on styrene-butadiene rubber (SBR)-mica composites have been studied with special reference to the technical properties and polymer-filler interaction. Silane-treated mica improves polymer-filler interaction, which subsequently enhances the tensile and other technically important mechanical properties. Failure surfaces of tensile, tear, and wear specimens have been examined under scanning electron microscope (SEM) and the fractographs have been correlated with the strength and failure mode of the composites.     

环保型乳聚丁苯橡胶制备技术进展

综述了乳液聚合制备不含亚硝胺化合物或生产过程中不产生亚硝胺化合物的环保型丁苯橡胶的方法,主要有使用不含亚硝基或不产生亚硝胺化合物的聚合终止剂、添加抑制剂、提高防老剂的持久性、削减部分易产生亚硝胺的次磺酰胺类促进剂用量等途径,并提出助剂行业的发展方向。     

Chlorination of vulcanized styrene-butadiene rubber using solutions of trichloroisocyanuric acid in different solvents

The chlorination of vulcanized styrene-butadiene rubbers (SBRs) with trichloroisocyanuric acid (TCI) has been studied. The solvent used to apply the TCI chlorinating solutions on the rubber plays an important role in the effectiveness of the treatment since the solvent determined the degree of penetration of TCI into the rubber and also different chlorinating species were produced depending on the nature of the solvent. Surface modifications produced on a synthetic sulfur-vulcanized SBR using TCI solutions in ethyl acetate (EA), methyl ethyl ketone (MEK), and EA + MEK mixtures have been compared. Furthermore, the effects of a solvent wipe with EA or MEK prior to the chlorination process were also considered. Surface modifications produced by the treatments were analyzed using ATR-IR spectroscopy, scanning electron microscopy (SEM), and X-ray photoelectron spectroscopy (XPS). Adhesion was obtained from the T-peel strength of treated rubber/polyurethane adhesive joints. TCI/MEK solutions produced a higher degree of surface modification than TCI/EA solutions, but TCI/EA solutions were more effective in removing zinc stearate from the rubber surface. When high TCI percentages (5-7 wt%) in EA solutions were used, a weak boundary layer (WBL) was created on the rubber surface as a consequence of the deposition of an excess of chlorinating agent on the rubber surface and of by-products (cyanuric and/or isocyanuric acid). The formation of the WBL led to a lack of adhesion in the rubber towards the polyurethane adhesive. When MEK was used as a solvent for TCI, this WBL was not produced on the rubber surface, and thus adhesion was considerably higher even when high concentrations of TCI/MEK were used. Similar effects were produced using EA + MEK mixtures as the solvent for TCI. The wiping of the rubber surface with MEK prior to the chlorination treatment led to good adhesion, irrespective of the percentage of TCI and the solvent used in the chlorinating solution.