苯噻氰

苯噻氰是一种性能优良的杀菌剂,有3种常见合成方法,包括2种2-巯基苯并噻唑法和1种氯甲基化法。一种2-巯基苯并噻唑法是用2-巯基苯并噻唑与溴氯甲烷反应生成2-氯甲基硫代苯并噻唑,2-氯甲基硫代苯并噻唑再与硫氰化钠反应得到苯噻氰;另一种2-巯基苯并噻唑法是先将溴氯甲烷与硫氰化钠反应生成硫氰酸氯甲酯,然后硫氰酸氯甲酯与2-巯基苯并噻唑反应得到苯噻氰。氯甲基化法是先用2-巯基苯并噻唑与多聚甲醛和氯化氢反应生成2-氯甲基硫代苯并噻唑,2-氯甲基硫代苯并噻唑再与硫氰化钠反应得到苯噻氰。     

2-巯基苯并噻唑

介绍橡胶硫化促进剂2-巯基苯并噻唑的物理性质和主要的制备方法。简要评述了2-巯基苯并噻唑在我国和日本的生产及需求现状,同时概述了2-巯基苯并噻唑作为促进剂的应用范围及其国内外价格。     

Ni-Co-W合金电沉积行为及成核机理

采用循环伏安、阴极极化曲线、电化学阻抗谱、计时电流等方法对Ni-Co-W合金的电沉积行为及成核机理进行研究.结果表明,Ni-Co-W合金的电沉积是一个存在成核行为的不可逆过程.Ni-Co-W合金的成核机制为瞬时成核,合金的电沉积由动力学和扩散过程混合控制,主要受动力学控制.     

石墨基体上电沉积铜成核机理的研究

通过循环伏安法和恒电位阶跃暂态法,研究硫酸铜-硫酸溶液中铜在石墨基体上的电沉积行为,并利用扫描电子显微镜观察石墨基体表面金属铜沉积颗粒的形态和分布。结果表明:在较正的电位区间内,铜的沉积遵从连续成核机理;而在较负的电位区间内,铜的沉积遵从瞬时成核机理。     

ChCl-EG低共熔溶剂中Ni的电沉积行为研究

对氯化胆碱-乙二醇(Ch Cl-EG)低共熔溶剂中Ni的电沉积行为进行研究。采用循环伏安法和计时电流法研究了Ch Cl-EG低共熔溶剂中电沉积Ni的电化学行为、成核生长机理,利用扫描电子显微镜(SEM)、能谱分析(EDS)对电沉积得到的镀层进行微观形貌和元素组成分析。结果表明,ChCl-EG低共熔溶剂的电化学窗口为2.55V,在ChCl-EG低共熔溶剂中镍的氧化、还原电位分别是0.1V、-0.96V,还原过程为一步还原,电极还原反应不可逆,镍沉积的成核机理属于三维瞬时成核,得到的镍镀层平整、致密。     

不同添加剂对Ni-Sn-Mn合金电沉积行为的影响

采用阴极极化曲线、循环伏安曲线、电化学阻抗和电位阶跃等电化学方法,研究了糖精(BSI)、1,4-丁炔二醇(BYD)及两种添加剂组合对Ni-Sn-Mn合金电沉积行为的影响。结果表明:加入不同添加剂均使Ni-Sn-Mn合金电沉积的阴极极化增大,沉积电位负移,对合金电沉积起阻化作用;不同添加剂作用下电沉积过程均为不可逆;加入BSI的电荷转移电阻大于加入BYD的电荷转移电阻,而加入BSI+BYD的电荷转移电阻最大;在不同添加剂作用下Ni-Sn-Mn合金电沉积无因次曲线接近理论连续成核曲线,电沉积结晶过程遵循三维生长方式的连续成核机制。     

氟硼酸铅镀液中电沉积钛基二氧化铅

以电沉积法从氟硼酸铅镀液中制备Ti基PbO2阳极(FB/PbO2)及其掺杂氟离子的FB/F - PbO2阳极.应用计时电位法研究了所制备阳极的电沉积成核速率,发现氟硼酸铅镀液在钛基表面电沉积二氧化铅的结晶速度比硝酸铅镀液更快.采用XRD和SEM技术对这两种电极进行了表征,并与传统的硝酸镀液制备的钛基二氧化铅对比,发现电...     

二硫化二苯并噻唑的催化合成

以2-巯基苯并噻唑和氨水为原料,双氧水作氧化剂,经催化剂A进行催化,合成了二硫化二苯并噻唑。通过考察催化剂种类、催化剂用量、氨水用量、物料配比、反应时间和反应温度对产率的影响,得出适宜的工艺条件为:选用催化剂A,用量为2-巯基苯并噻唑的1%,氨的加入量为n(2-巯基苯并噻唑)∶n(氨水)=1∶6.0,双氧水用量为n(2-巯基苯并噻唑)∶n(双氧水)=2∶1.2,反应时间3 h,反应温度50℃。在此条件下,二硫化二苯并噻唑的产率为90.7%,熔点为165.3~168.7℃。二硫化二苯并噻唑粗品通过甲苯进行一次重结晶后,熔点可达173.6~175℃。     

电解铜箔添加剂配方优化

在高电流密度下用直流电沉积法制备了电解铜箔.电解液基础成分为:CU2+80～90g/L,H2SO4120～130g/L和Cl-30～40mg/L.用正交试验法研究了聚乙二醇,2-巯基苯并咪唑,硫脲、明胶等4种添加剂对电解铜箔力学性能的影响.最佳配比为:聚乙二醇0～5.5 mg/L,2一巯基苯并咪唑0～6.0mg/L,硫脲0～3.0 mg/L,明胶0～4.5 mg/L.由此制备的铜箔,其常温抗拉强度与延伸率分别是411.3 MPa和9.3%,高温抗拉强度与延伸率分别是209.2 MPa和2.9%.     

苯并噻唑类化合物在银上的吸附机理研究

本文利用线性电势扫描的方法研究了几种苯并噻唑类化合物及巯基苯基四氮唑在银上的吸附机理。结果表明:2.巯基苯并噻唑和巯基苯基四氮唑以化学吸附方式,通过分子上巯基与银表面的作用形成分子紧密排列的吸附层。25℃下,PMT可以在银表面形成紧密单层。这种吸附在较高吸附温度下可以转化为多层,且完全覆盖银表面。在含Br~-的溶液中,它可以阻碍Br~-与表面的接触。在较大的浓度下,2-甲基苯并噻唑和苯并噻唑也可以在银表面的某些位置,通过杂环上的S原子(或N原子)形成松散的吸附,但这种吸附层不能完全覆盖银表面。电镜实验也表明以上物质在银表面发生了作用。     

Vinyl polymerization, 399. Polymerization of methyl methacrylate with sodium polystyrenesulfonate in presence of polyethyleneglycol

The effect of polyethyleneglycol on the radical polymerization of methyl methacrylate initiated with an aqueous solution of sodium polystyrenesulfonate was studied. Under the definite condition, the conversion of methyl methacrylate raised from 6.6 to 100% by the addition of polyethyleneglycol. It was concluded that polyethyleneglycol acted only as a host of Na⁺, but not as a phase transfer catalyst.     

高吸水性树脂的制备及交联剂对树脂吸水性能的影响

用反相悬浮聚合和滴加单体的方法制备以聚乙二醇双丙烯酸酯交联的聚丙烯酸钠高吸水性树脂。详细探讨了温度，引发剂和单体浓度，油水比等最佳反应条件。     

双生表面活性剂微乳液的制备及其相行为研究

制备了双生表面活性剂α-磺基硬脂酸聚乙二醇双酯钠盐/醇/正辛烷/水微乳液体系,绘制了其拟三元相图,探讨了不同碳链长度的醇及0.1mol/LKCl、NaOH、HCl溶液对微乳区域的影响,利用电导率分析了微乳液的结构类型。结果表明:以α-磺基硬脂酸聚乙二醇双酯钠盐作为乳化剂,可以制备稳定的微乳液。在中等链长范围内,作为助表面活性剂的醇类,链长的比链短的醇具有更好的助活作用。电解质溶液一般使微乳区域缩小,以电解质溶液或纯水为分散介质的微乳液的电导率变化趋势基本相同。     

α-磺基硬脂酸聚乙二醇双酯钠盐的合成

以α 磺基硬脂酸和聚乙二醇为原料 ,经酯化、中和合成双生表面活性剂α 磺基硬脂酸聚乙二醇双酯钠盐。实验结果表明 ,在催化剂用量为 0 6 % (基于反应体系的质量分数 ) ,酸醇的量比为 2 5∶1 0 ,反应时间 3h ,反应温度 135～ 14 0℃时 ,产物收率达 87 0 %。     

Synthesis and characterization of starch-based polyurethane foams

Starch-based polyurethane foams were synthesized by reacting a mixture of starch and polycaprolactone triol with an aliphatic diisocyanate, in the presence of water as blowing agent. Some foams were also prepared by adding a certain amount of polyethyleneglycol. The reaction kinetics is affected by the presence of starch due to the higher viscosity related to the presence of the high molecular weight polysaccharide. Starch-based polyurethanes show higher glass transition temperatures and lower thermal stability. Cellular materials with different mechanical properties can be obtained by varying the amount of starch and by controlling the relative amount of polycaprolactone triol and polyethyleneglycol in the composition. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 68:739–745, 1998     

Effect of polyethyleneglycol on polymerization of methyl methacrylate initiated by sodium salt-type macromolecular electrolytes

Summary The effects of polyethyleneglycol (PEG) on the radical polymerizations of methyl methacrylate initiated with the aqueous solutions of such macromolecular electrolytes as sodium polyphenolate and sodium polycarboxylate were studied. PEG was found to promote the polymerizations initiated by such sodium salt-type's macromolecular electrolytes.Vinyl Polymerization. 415.     

PET结晶速率的研究进展

阐述了聚对苯二甲酸乙二醇酯(PET)的结晶机理,综述了相对分子质量、残余助剂及末端基、物理老化和应力4个因素对PET结晶速率的影响,并着重介绍了提高PET结晶速率的方法,包括加成核剂、结晶促进剂和与其他聚合物共聚、共混。     

Phase diagrams of water and sodium dodecyl sulfate combined with four commercial nonionic surfactants

Phase diagrams in which water was combined with sodium dodecyl sulfate, plus one of four nonionic surfactants, as well as an aliphatic oil, were determined by visual observation and low-angle X-ray diffractometry. The results agreed with earlier investigations on specially synthesized polyethyleneglycol alkyl ether surfactants, except that the extended water-in-oil microemulsion areas were not found with the commercial surfactants.     

聚乙二醇400对水性复膜胶合成及性能的影响

将聚乙二醇(PEG)作为空间位阻型乳化剂、润湿剂和增塑剂引入到原水性干法复膜胶的反应体系中,讨论了PEG的相对分子质量(M_n)和用量对乳液的合成及使用性能的影响。结果表明:当w(PEG-400)=1.15%(相对于总单体而言)时,聚合反应的稳定性最佳,乳液的粘接性能和机械适应性明显提高。     

Polyethyleneglycol catalytic dehydration kinetics in the liquid phase

Eleven representative polyethyleneglycol (25322–68–3) catalytic dehydration reactions have been studied in the liquid phase at atmospheric pressure. The aim of this research is to build a kinetic model representative of the polyethyleneglycol dehydration process. Three types of reaction take place simultaneously in the process: cyclisation, condensation and alcoholysis. Activation energies and frequency factors are given, and the relationships between kinetic parameters and chain length of reactants and products are discussed according to the reaction type.