Effects of processing conditions on the curing of a vinyl ester resin

The effects of temperature, initiator, and accelerator levels on the curing of an epoxy bisphenol‐A vinyl ester resin Derakane® 411‐45 (formulated with styrene) were investigated by gel‐time and exotherm‐peak measurements on bulk samples. It was observed that the gel time was reduced as the initiator or accelerator ratio increased. Except at higher contents of the accelerator, a small kinetic plateau was seen in the gel curve and a shift of the maximum exotherm toward high temperatures in the DSC curves. This was explained by the dual role played by the accelerator species. A regression analysis of all gel‐time data showed a dependence of 3/2 order in the accelerator and first order in the initiator concentrations. Thus, for this polymerization initiation system, the gel time can be predicted for any initiator and cobalt levels and at any temperature within the ranges studied. The effect of the initiator on the unreacted styrene and vinyl ester was also examined. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 1146–1154, 2002; DOI 10.1002/app.10403     

有机硅丙烯酸酯增深剂的制备及应用

由乙烯基三乙氧基硅烷与KH-550、丙烯酸酯类单体在阴/非离子表面活性剂存在下，通过乳液聚合制得带蓝光的半透明有机硅丙烯酸酯乳液．该乳液粘度小，有机硅质量分数15％，总固体质量分数30％，该增深剂既可单独使用，也可与氨基硅油乳液复配，经蓝色16电力纺、黑色03双绉等真丝产品增深，其增深度可达15％，但亲水性有所下降．     

绿色润滑剂的生物降解性及特点

阐述了绿色友好润滑剂的生物降解性和摩擦化学特点，提出了绿色润滑剂在发展过程中存在的主要问题，并对未来的发展趋势进行了预测。     

丙烯酸酯类助剂ACR的生产简况及市场分析

概述了ACR的功能、生产简况及市场趋势。     

聚甘油脂肪酸酯类乳化剂制备乳液功效性研究

测定了聚甘油-6 二硬脂酸酯、聚甘油-10 硬脂酸酯、聚甘油-10二棕榈酸酯制备的乳液的粒径、皮肤水分含量、经皮水分流失TEWL。结果表明,聚甘油-6 二硬脂酸酯制备的乳液分散性较好,乳液粒径分布较小;聚甘油-10二棕榈酸酯制备的乳液在皮肤水分含量、经皮水分流失TEWL值上优于其他2组。     

The Structure of the Irreversibly Bound Adhesion Promoter-Substrate Interfacial Layer of γ-Aminopropylsilanetriol on Crystalline Si, as Measured by XPS and FTIR

The irreversibly bound interfacial layer deposited by the γ-aminopropysilanetriol adhesion promoter onto a crystalline silicon substrate, which remains even after profuse washing, was found by XPS to have resulted from the fragmentation and rearrangement of the original γ-aminopropylsilanetriol molecule. A mechanism is proposed, involving the homolytic scission of the terminal N-C bond. One of the subsequent reactions is believed to involve hydrogen loss by abstraction and the formation of a terminal vinyl group, which bonds to the substrate. Support for this mechanism is found in IR spectroscopy of this layer.     

由二氧化碳出发合成有机碳酸酯

对以二氧化碳为原料合成有机碳酸酯的环氧路线、酯交换和直接合成方法作了综合评述 ,认为直接合成是最佳的合成路线。碳酸酯的直接合成可在均相及多相催化体系中进行 ,负载金属、金属甲氧基化合物及碱均可作为催化剂。直接法研究的关键在于高性能催化剂的开发、由二氧化碳对金属 -氧键插入反应导致的催化循环的构筑及耦合反应的应用。     

Chemo-enzymatic synthesis of amino acid-based surfactants

The application of lipases to the synthesis of amino acid-based surfactants was investigated. Low yields (2–9%) were obtained in the acylation of free amino acids, such as l-serine and l-lysine, as well as their ethyl esters and amides with fatty acids, owing in part to low miscibility of the reactants. When the N-carbobenzyloxy (Cbz)-l-amino acids were used in an effort to improve miscibility of the amino acid derivatives with the acyl donor, a dramatic improvement was observed for N-Cbz-l-serine (92% yield) but not for N _α-Cbz- or N _ζ-Cbz-l-lysine (7 and 2% yield, respectively). As an alternative, and efficient synthesis of N _ζ-acyl-l-lysines was developed, based on the regiospecific chemical acylation of copper(II) lysinate. In pursuit of a general route to amino acid-fatty acid surfactants, the utility of a polyol linker was investigated. Thus, the glycerol ester of N _α′ N _ζ-di-Cbz-l-lysine was prepared and evaluated as a substrate for acylation. As expected, this and other glycer-1-yl esters of N-protected amino acids were excellent substrates for lipase-catalyzed acylation. Their reaction with myristic acid in the presence of Novozyme resulted in the regioselective acylation of the primary hydroxyl group of the glycerol moiety to afford the corresponding 1-O-(N-Cbz-l-aminoacyl)-3-O-myris-toylglycerols with conversions of 50–90%. These were readily deprotected to give a range of 1-O-(aminoacyl)-3-O-myristoyl-glycerols with overall yields of 27–71%.     

Direct ethoxylation of fatty methyl ester over Al-Mg composite oxide catalyst

For the purpose of estimating the reaction mechanism of the direct ethoxylation of a fatty ester in the presence of an Al-Mg composite oxide catalyst, a labeled fatty methyl ester C₁₁H₂₃CO¹⁸OCH₃ containing ¹⁸O isotope was synthesized and directly ethoxylated. The product was evaluated by gas chromatography-mass spectrometry (GC-MS). The GC-MS spectra showed that the ¹⁸O isotope label was present only in the methoxy group at the molecular end of the ethoxylated fatty methyl ester. This supports the reaction mechanism of coordination anionic polymerization where the bond between the acyl and methoxy groups of the fatty methyl ester molecule was broken, caused by the bifunctional effect of the acid-base active sites; an intermediate chemisorption species was formed; and then ethylene oxide was addition-polymerized sequentially, in parallel.     

柠檬酸的应用与开发

本文介绍了柠檬酸的生产概况、用途和柠檬酸深加工产品的制法及用途。开发新的使用途径是柠檬酸生产行业的发展方向。