Mercapto‐modified copolymers in elastomer blends. IV. The compatibilization of natural rubber/EPDM blends

Ethylene—propylene—diene functionalized with mercapto groups (EPDMSH) was employed as compatibilizing agent for natural rubber (NR)/EPDM blends, resulting in a substantial increase of the ultimate tensile strength of these blends without affecting the elongation at break. There is also a decrease of the curing time with the addition of as low as 2.5 phr of EPDMSH, mainly in NR/EPDM (70:30 wt %) blend, indicating the accelerator effect of this functionalized copolymer. This copolymer also increased the crosslink degree and the gel content. From dynamic mechanical analysis (DMTA), it was demonstrated that EPDMSH improves the covulcanization process. The reactive compatibilization of EPDMSH was demonstrated by the presence of insoluble material in nonvulcanized/compatibilized blends and by its thermogravimetric (TGA) analysis. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 2892–2900, 2002; DOI 10.1002/app.10283     

Preparation and recovery of polysulfone affinity membrane with mercapto as chelating group for Hg2+ cations

Highly qualified homogeneous poly(benzylsulfone) plate affinity membrane with mercapto group (PSF‐SH) was prepared successively through reactions between chloromethyl polysulfone matrix membrane and thiourea, and then alkalic hydrolysis. The mercapto‐functionalized polysulfone affinity membrane was utilized for the adsorption of Hg²⁺ cations through the coordination of the mercapto group and Hg²⁺ cations, in which the effects of the morphological and the structure of the affinity membrane on the chelating properties were investigated. The chelating conditions, including concentration of Hg²⁺, and temperature and pH of the introductory solution had significant influence on the chelating capacity of PSF‐SH affinity membrane. The highest static and dynamic chelating capacity of PSF‐SH plate membrane for Hg²⁺ cations were 398 and 403 μg/cm² per membrane, respectively, which demonstrated that the resultant polymer membrane was a highly efficient affinity chromatography for Hg²⁺. The affinity membrane containing mercapto group can be conveniently recovered by dilute hydrochloric acid for coordination of Hg²⁺ cations, which would have wide application for the treatment of waste water containing heavy metal cations. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 2514–2522, 2007     

3-Mercaptopropionic acid as a new reagent for the industrially applicable synthesis of highly pure O-desmethylvenlafaxine from venlafaxine

3-Mercaptopropionic acid was introduced as a cheap new O-demethylating agent as exemplified by its application in the synthesis of antidepressant O-desmethylvenlafaxine from venlafaxine. The application of 3-mercaptopropionic acid allowed high conversion of venlafaxine to O-desmethylvenlafaxine and a facile workup, which enabled the isolation of the desired O-desmethylvenlafaxine with a high >99.8% chromatographic purity and 76% yield by a simple extractive workup followed by the precipitation.     

Microwave assisted enzyme catalysis for synthesis of <Emphasis Type="Italic">n-</Emphasis>butyl dipheyl methyl mercapto acetate in non-aqueous media

n-Butyl dipheyl methyl mercapto acetate is an important pharmaceutical intermediate, having applications in the synthesis of Modafinil, a CNS stimulant drug. The current process is highly polluting and requires alternate green processes. Synthesis of it was carried out via lipase in the presence of microwave irradiation. Optimization of reaction conditions, such as catalyst loading, mole ratio of reactants, reaction temperature, water concentration and reusability of catalysts under the microwave irradiation was done. Among all, the commercially available lipases Novozym 435 was found best and gives the conversion 34% in 24 h at 60°C. A ping–pong bi–bi model with substrate n-butanol inhibition at higher concentration was found to be suitable for kinetics of the reaction.     

含巯基聚硅氧烷改性环氧树脂的制备及性能

以双酚A环氧树脂（E51）为基料、聚醚胺（D?230）为固化剂、含巯基聚硅氧烷（PMMS）为改性剂,分别经过简单物理混合和化学改性的方法,制备了一系列聚硅氧烷改性环氧树脂（E51⁃D⁃PMMS）固化物。通过衰减全反射红外（ATR?FTIR）和X射线衍射仪（XRD）表征了固化物的结构特征;通过拉伸测试和冲击实验、扫描电子显微镜（SEM）、接触角测量（CA）、动态热力学分析（DMA）及中性盐雾实验探究了改性固化物的力学性能、热稳定性、防腐性能等。结果表明,化学改性的E51?D?PMMS固化物的综合物理化学性能优于简单物理改性的,当PMMS含量为1 %（质量分数,下同）时,改性固化物的拉伸强度为74.63 MPa,较改性前提高了13.5 %,断裂伸长率提高了40.2 %,冲击强度提高了43.7 %;水接触角从改性前的72.8 °增至100.3 °,表面能从39.4 J/m²降至17.4 J/m²,吸水率下降了44 %,耐水性能大大增强;其防腐性能和玻璃化转变温度（T_g）也有一定的提升。     

巯基有机硅溶胶-凝胶涂层对铜合金H90的腐蚀防护性能研究

目的 研究巯基有机硅溶胶-凝胶涂层对铜合金H90的保护性能。方法 以不同比例的巯基丙基三甲氧基硅烷（MAPMS）与正硅酸乙酯（TEOS）为前驱体,以乙酸作为催化剂,制备含巯基官能团的溶胶-凝胶,并通过浸涂法将该溶胶-凝胶涂层施加到铜合金H90上,并在120 ℃下烘干成膜。利用电化学、盐雾、接触角等一系列的手段考察巯基有机硅溶胶-凝胶涂层在铜合金H90基材上的防腐蚀、疏水性、铅笔硬度等性能。结果 当MAPMS与TEOS物质的量比达到1.5∶1时,自腐蚀电流密度为1.16×10?8 A/cm2,膜层铅笔硬度可达5H,在H90黄铜上的附着力等级达到0级,具有最佳的防腐蚀性能。中性盐雾测试中,物质的量比为1∶1的测试组在第8 d时出现了少量腐蚀斑点,但在接下来的30 d内,腐蚀并未扩大;其他测试组在30 d测试中,未出现明显腐蚀。结论 巯基有机硅溶胶-凝胶涂层具有良好的硬度以及附着力,并能显著提高铜合金H90表面防腐蚀性能。     

巯基化合物的制备

巯基化合物因其是一类重要的工业原料和重要的医药中间体而受到人们的广泛关注．研究开发其制备技术成为开发该系列化合物的重点。多数产品国内供不应求,极具发展潜力。本文详细综述了巯基化合物的制备方法,同时对制备方法提出了评价。     

巯基链转移聚合法制备超支化聚甲基丙烯酸-β-羟乙酯

设计并合成新型含被保护巯基的苯乙烯型AB单体,并以其为支化单体,甲基丙烯酸-β-羟乙酯(HEMA)为聚合主单体,DMSO为聚合溶剂,AIBN为引发剂,自由基聚合法制备可溶于水的超支化聚甲基丙烯酸-β-羟乙酯(PHEMA),同时建立一种新型超支化聚合法——巯基链转移超支化聚合法。用凝胶渗透色谱、1HNMR、DSC等对AB支化单体、PHEMA进行一系列结构和性能表征。实验结果表明,随着AB支化单体加入量的增加,聚合物的重均分子量Mw逐渐增加,而其Tg则呈下降趋势,在水中溶解度增加,说明聚合物发生超支化。     

疏基棉分离富集-滴定法测定高含量银

讨论了一种化学滴定测定高含量银的方法．在2．23mol/L硝酸介质中，巯基棉对Ag^ 有较强的吸附作用，其饱和吸附量可达53mg／g．用10mol/L硝酸解脱，以铁铵矾作指示剂，硫氰酸铵滴定银．对原矿样经过王水溶解，在碱性条件下以过量氨水分离杂质，以本法测定，其误差较允许误差还低．该法操作手续简便、快速，适用于高含量银的测定．     

含巯基有机硅改性水性苯丙乳液的制备及性能

以丙烯酸丁酯(BA)、甲基丙烯酸甲酯(MMA)、苯乙烯(St)和丙烯酸(AA)为反应单体,利用羟基硅油(SO)与3?巯丙基甲基二甲氧基硅烷(MPDMS)制备的含巯基有机硅(PMMS)为改性剂,通过种子乳液聚合的方法,制备了一系列有机硅改性水性苯丙复合乳液.通过红外光谱(FTIR)、核磁共振(NMR)和凝胶渗透色谱(GP...