二丁基氧化锡合成方法的工艺改进

用复合溶剂代替乙醚作溶剂,通过格氏反应由四氯化锡制得粗四丁基锡(简称TBT),四丁基锡含量≥85%,三丁基氯化锡含量≤15%,将粗TBT与四氯化锡在催化剂的作用下反应,反应完毕后,将反应物用酸洗,分相制得粗二丁基氯化锡,再减压脱水制得精二丁基氯化锡,二丁基氯化锡和氢氧化钠反应制得二丁基氧化锡,以SnCl4为原料合成二丁基氧化锡的小试收率以含锡量计为95.26%.     

二丁基氧化锡的制备改进

用甲苯和少量四氢呋喃作溶剂 ,通过格氏反应由四氯化锡制备了四丁基锡 ,四丁基锡与四氯化锡直接反应冷却后得二丁基二氯化锡粗品 ,随后用二丁基二氯化锡粗品的乙醚溶液直接水解制备二丁基氧化锡高并反应收率均大于 90 %。     

二丁基氧化锡在糖衍生物选择性合成中的应用

二丁基氧化锡和糖上的羟基选择性地形成亚甲锡烷基缩醛,通过聚合作用使处于聚合体不同位置的羟基显示了不同的电负性和亲核性,进行选择性反应合成糖衍生物.因此,利用二丁基氧化锡这种反应特性,分别对其在活性糖的保护、形成糖聚合体和糖基化等方面的应用进行了阐述,为该试剂在糖衍生物合成中的广泛应用提供参考.     

MDI基碳化二亚胺耐水解稳定剂的研制

在有机磷催化剂作用下，以二苯基甲烷二异氰酸酯(MDI)合成碳化二亚胺预聚体，采用单官能度带活泼氢化合物封端得到耐水解稳定剂。通过对MDI缩合过程动力学研究，优化了MDI基碳化二亚胺耐水解稳定剂的合成条件。实验表明较适宜的反应条件为：温度180～230℃，催化剂用量2．0％～3．0％。并对成品进行了简单的表征。最后将MDI基耐水解稳定剂与Bayer公司的Stabaxol-1进行了应用性能的对比，实验合成样品耐水解性能达到Stabaxol-1的70％水平。     

二丁基二硫代氨基甲酸镧的合成及其在丁苯橡胶中的应用

研究了二丁基二硫代氨基甲酸镧配合物的合成,以工业级的二丁基二硫代氨基甲酸钠与氯化镧为反应物,采用液-液合成法合成了二丁基二硫代氨基甲酸镧,作为硫化促进剂应用于丁苯橡胶的基础配方中。结果表明二丁基二硫代氨基甲酸镧对丁苯橡胶的硫化性能有下列作用：延长燃烧时间,提高碳化速率。提高材料力学性能。     

自粘性高透明有机硅凝胶制备与性能

采用α,ω－二羟基聚二甲基硅氧烷为基础胶,二丁基二乙酸锡（D－70）及二月桂酸二丁基锡（D－80）为催化剂,异氰酸酯类为交联剂,研究了室温硫化硅橡胶（RTV）制备自粘性高透明有机硅凝胶及其成膜性能,探讨了催化剂用量、交联剂、预加热时间、预加热温度对凝胶性能的影响,通过傅里叶变换红外光谱表征了产物结构。结果表明,制备PDMS凝胶最佳制备条件：交联剂（以PDMS基胶为基准）用量为1．2％,催化剂用量为0．48％,预加热温度控制在60℃;红外光谱分析表明催化剂促进交联剂和PDMS基胶的反应作用明显。     

异氰脲酸三缩水甘油酯改性水性聚酯的性能研究

引入三官能度环氧端基的异氰脲酸三缩水甘油酯(TGIC)改性水性聚酯树脂,利用羧基与环氧基开环反应生成酯键和羟基并进一步反应得到六元支化岛状结构水性聚酯树脂。通过红外光谱、X射线衍射和凝胶色谱对异氰脲酸三缩水甘油酯(TGIC)改性水性聚酯树脂进行微观结构的分析,对比了异氰脲酸三缩水甘油酯、季戊四醇和三羟甲基丙烷作为支化组分对水性聚酯树脂贮存稳定性、T弯、耐热性能、耐水煮性能、耐溶剂性能等的影响,发现异氰脲酸三缩水甘油酯(TGIC)改性水性聚酯树脂具有更好的T弯与耐热性,其他性能包括耐溶剂擦拭性、耐水煮性以及耐化性等与使用其他脂肪族支化单体的水性聚酯相当。     

南大—701胶

一、南大——701胶的制造方法 1.原理末端含羟基的聚二甲基硅氧烷,即室温硫化硅橡胶在二丁基二月桂酸锡的催化下与过量的苯胺甲基三乙氧基硅烷(即南大一42)作用生成以乙氧基封端的聚二甲基硅氧烷:H NHCH:51(OCZH。)s ln C6H。二丁墓     

有机锡酯化合成三氯蔗糖研究

研究了通过有机锡正二丁基氧化锡酯化作用、以及酰化、氯化等步骤制备三氯蔗糖的工艺,考察了有机锡与蔗糖配比对反应的影响,结果表明有机锡正二丁基氧化锡和蔗糖的最佳比例为1.01～1.03,确立了氧化反应的三个温度平台,使副产物减少且反应平稳.该工艺适合工业化生产三氯蔗糖.     

原子荧光法测定二丁基二月桂酸锡中锡含量

经氧化、分解及消化后,二丁基二月桂酸锡转化成无机锡,分别采用常规化学滴定法、电感耦合等离子质谱法(ICP-MS)及原子荧光光谱法(AFS)测定二丁基二月桂酸锡中的锡含量,结果表明这3种测试手段所测数值基本一致。较其他两种方法而言,原子荧光光谱法具有简便、快速、准确、灵敏度高等特点。针对原子荧光光谱法的加标回收实验结果为99.2%～100.8%,表明该法测定的结果准确可靠,适合作为测定二丁基二月桂酸锡中锡含量的常规检测方法。     

二苄基锡二对硝基苯甲酸酯的合成及表征

以苄基氯和锡粉为原料,n(Sn)∶n(BzCl) =1.0∶1.0的条件下,在乙苯中直接合成二苄基二氯化锡( Bz2 SnCl2),产率达80％以上;以二苄基二氯化锡、对硝基苯甲酸和三乙胺为原料,合成了二苄基锡二对硝基苯甲酸酯[ Bz2 Sn( O2 CPhNO2)2],当n(Bz2 SnCl2)∶n(HOCOPhNO...     

Role of sulfonic acids in the Sn-catalyzed transesterification of dimethyl carbonate with phenol

Diphenyl carbonate, the key intermediate of the non-phosgene polycarbonate manufacturing process, can be produced by the transesterification of dimethyl carbonate with phenol in the presence of dibutyltin oxide. The use of an alkyl or aryl sulfonic acid in conjunction with dibutyltin oxide significantly enhances the activity of dibutyltin oxide. ¹⁹F and ¹¹⁹Sn NMR studies suggest the formation of tin complex containing strongly electrophilic sulfonate ligand from the reaction of dibutyltin oxide with alkyl or aryl sulfonic acid. Various factors affecting the transesterification of dimethyl carbonate with phenol were investigated.     

电镀锡渣制备氯化亚锡和锡酸钠

介绍了从电镀别针厂产生的大量锡渣废料中制取氯化亚锡和锡酸钠的原理、工艺流程和工艺条件。讨论了温度、pH值和氧化剂对酸解、碱解反应的影响。实验表明 ,采用浓盐酸和氢氧化钠处理电镀锡渣的工艺流程简单 ,设备简单 ,条件容易控制 ,不但处理了大量含锡废渣 ,而且制取了合格的氯化亚锡和锡酸钠产品 ,回收率达 70 %以上 ,使电镀锡达到循环利用的目的 ,取得了明显的经济效益。     

Katalytische Oligomerisierung von Fettstoffen

Catalytic Oligomerization of Fatty Derivatives A new catalytic reaction is presented to oligomerize conjugated fatty acids or esters under mild reaction conditions. Metal salts such as tin dichloride, tin tetrachloride, titanium tetrachloride or iron trichloride are used as catalysts, and yields of oligomers of 70% are reached. In particular, a bimetallic catalyst system of molybdenum pentachloride and tin dichloride proved to be highly active. Especially remarkable is the distribution of the oligomers: Instead of a Schulz-Flory-distribution with dimers as main products a Poisson-distribution is formed with trimers as most important oligomers.     

Ethylene‐co‐vinyl acetate copolymer crosslinking through ester–alkoxysilane exchange reaction catalyzed by dibutyltin oxide: mechanistic aspects investigated through model compounds by multinuclear NMR spectroscopy

It was shown that the crosslinking of ethylene‐co‐vinyl acetate (EVA) copolymer by a tetraalkoxysilane in molten state, in the temperature range 100–250 °C, was obtained only in the presence of dibutyltin oxide. At this temperature EVA pendant ester groups readily react with dibutyltin oxide to give a dimeric 1‐alkoxy‐3‐acetoxytetrabutyldistannoxane distributed along the polymer chains. The exact role of this tin compound in the ester–alkoxysilane reaction was elucidated through reactions of the tetraalkoxysilane with parent tin compounds: tributylethoxytin, dimeric diacyloxydistannoxane and finally a dimeric 1‐alkoxy‐3‐acyloxydistannoxane, obtained by reaction of the dibutyltin oxide with a model ester instead of the EVA‐ester pendant group. Ligand exchanges on tin atoms characterized by multinuclear NMR spectroscopy (¹H, ¹³C and ¹¹⁹Sn) showed that substitutions were selective and concern only the exo‐cyclic tin ligand (OR or OCOR′) without alteration of the dimeric distannoxane structure. Furthermore, these ligand exchanges occurred at room temperature. This approach with model compounds gave evidence that the crosslinking occurred via an alkoxy‐Sn/alkoxy‐Si exchange on the exo‐cyclic sites of the distannoxane structure formed in situ. This distannoxane was shown to be an efficient catalyst of this transesterification. The temperature of formation of this catalytic species governed the temperature of the beginning of the crosslinking reaction. Copyright © 2004 Society of Chemical Industry     

甲基丙烯酸聚乙二醇(400)单酯的合成研究

以对苯二酚作为阻聚剂,氯化亚锡为助阻聚剂,对甲苯磺酸作催化剂,甲基丙烯酸与聚乙二醇(400)为原料进行直接酯化反应合成单体甲基丙烯酸聚乙二醇(400)单酯,考察了氯化亚锡用量、催化剂用量、反应温度和反应时间对反应结果的影响,确定了最佳的反应条件。     

新型有机锡热稳定剂——二丁基锡双(异辛酸巯基乙酯)的合成与表征

利用异辛酸巯基乙酯和二丁基二氯化锡进行了取代反应,并通过水洗、分液、减压蒸馏,合成了一种新的有机锡化合物二丁基锡双(异辛酸巯基乙酯)(DBTMO)。研究了反应温度、反应时间、反应物料摩尔比和盐酸吸收剂用量对反应收率的影响,得出最佳工艺条件为:反应温度86℃,盐酸吸收剂选用2.5 mol/L的NaOH水溶液,反应过程中异辛酸巯基乙酯与二丁基二氯化锡的摩尔比为3.0∶1.0,在该工艺条件下反应3 h,产品收率达96%以上,精制后产品质量分数w(DBTMO)>99%。对目标产品进行了表征,通过红外光谱法,可以得到νC O=1 735 cm-1,νC—O=1 247 cm-1,νSn—C=630 cm-1和νSn—S=528 cm-1;用元素分析法测得该产品的C,H,O,S,Sn的质量分数分别是:51.77%,8.63%,9.86%,9.86%,11.80%;用衍生化的气相色谱-质谱法确定了其相对分子质量是638.1。使用热解重量分析法和差热分析法测定了DBTMO在PVC中的热稳定性,并与二丁基锡双(巯基乙酸异辛酯)(DBTTGB)进行了比较研究,两者的热稳定性能相近。该文合成的DBTMO的新颖性,已为教育部科技查新工作站(120)2006年12月12日出具的第2006350号《科技查新报告》所证实。     

Linear polythioesters. XXII. Products of interfacial polycondensation of bis(4-mercaptomethylphenyl)sulfide with some aliphatic and isomeric phthaloyl dichlorides

New polythioesters were obtained by interfacial polycondensation of bis(4-mercaptomethylphenyl) sulfide with some aliphatic and isomeric phthaloyl dichlorides. To determine optimal conditions for polycondensation, the polythioester from bis(4-mercaptomethylphenyl) sulfide and sebacoyl dichloride was chosen as a model system. The influence of some factors on the reduced viscosity and the yield were studied. Polythioesters from aliphatic and isomeric phthaloyl dichlorides were prepared under the same optimal conditions as those established for the reaction of the dithiol with sebacoyl dichloride. The structure of all polythioesters was determined by elementary, infrared spectra, and X-ray analysis. Initial decomposition temperature and maximum rate of decomposition temperature were defined from the curves of thermogravimetric analysis. Some physicochemical, mechanical, and electrical properties have been determined. © 1994 John Wiley & Sons, Inc.     

Kinetic evaluation of tin‐POMS catalyst for urethane reactions

We report the activity for a new tin‐polyhedral oligomeric metal silsesquioxane (POMS) catalyst in 1‐butanol and 2‐butanol model reactions with 4,4′‐methylenebis(cyclohexylisocyanate) (H₁₂MDI) in toluene and N,N‐dimethylformamide (DMF). Kinetic rate constants for varying levels of tin‐POMS ranging between 100 ppm and 1000 ppm tin are reported. We observed urethane reactions in toluene to follow second order reaction kinetics, whereas similar reactions in DMF followed first order reaction kinetics. We determined tin‐POMS is an efficient catalyst system for urethane reactions and found the new catalyst to be easy to handle, soluble, and very effective for catalyzing urethane reactions. By direct comparison of a model reaction between tin‐POMS and dibutyltin dilaurate (DBTDL), tin‐POMS was found to be quite similar to DBTDL for urethane catalytic activity. In addition, we show the efficacy for tin‐POMS to be an excellent polyurethane reaction catalyst through a model reaction of H12MDI with 2000 g/mol poly(ε‐caprolactone) diol. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008