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排序方式: 共有133条查询结果,搜索用时 140 毫秒
1.
In this study, a low temperature-curable and alkylphenol ethoxylate-free acrylic emulsion was synthesized with diacetone acrylamide (DAAM) and adipic dihydrazide (ADH) as a crosslinking system; butyl acrylate (BA), ethyl acrylate (EA), methyl methacrylate (MMA), and acrylic acid (AA) as monomers; vinyl siloxane as a modifier; sodium-dodecyl sulphate (SDS) and AEO-9 as a compound emulsifier by means of semicontinuous emulsion polymerization. The optimal polymerization conditions by weight proportion determined by the orthogonal experiments were emulsifier amount, 4%, initiator amount, 0.5%, DAAM amount, 2.5%, and core–shell ratio, 3/2. Three flame-retardant additives, namely, ammonium polyphosphate (APP), FR-5, and organic montmorillonite, were mixed with the acrylic emulsion to synthesize the flocking adhesive SA. The char length, afterglow time, and afterflame time of the flocking fabrics were characterized to evaluate the fire-retardant properties of the adhesives. The results clearly evidence an outstanding improvement in fire-retardant properties using adhesive SA based on good flocking fastness and fabric handle.  相似文献   
2.
以松香、反丁烯二酸(FA)、十二烷基苯酚(DP)、对特辛基苯酚(OP)和多聚甲醛为原料,通过一步法工艺合成高性能松香改性酚醛树脂,分别考察了两种t昆合烷基酚物质的量比、酚与醛物质的量比、FA加量及FA与松香发生D—A环化加成反应温度对树脂黏度、软化点和正庚烷值等性能的影响,确定了合成高性能松香改性酚醛树脂的最佳配方工艺:DP与OP物质的量比为1:1.1,酚醛物质的量比为1:2.6,FA加量为2.9%,加成反应温度为210℃。在此工艺条件下制得的松香改性酚醛树脂具有高黏度、高软化点、高溶解性,产品性能为:酸值〈25mgKOH/g,25℃黏度22000—24000mPa.sl软化点168~170℃,正庚烷值6—8mL/2g。  相似文献   
3.
This report describes the application of LC–MS/MS for the separation of dodecanol (C12OH) and homogenous fatty alcohols ethoxylated (AE) containing a dodecyl moiety and 1–9 ethoxy groups. These ethoxylates and free alcohol were derivatized for LC–MS/MS analysis with phenyl isocyanate (PIC). The derivatives of analytes with PIC were separated using a C18 column. Gradient elution with a mixture of ethyl acetate and acetonitrile (5 mM) was employed. The described determination method is characterized by low detection limits (range from 0.005 µg L?1 for: C12OH, C12EO2–7 to 1 µg L?1 for C12EO1) and quantification limits (range from 0.01 µg L?1 for: C12EO5–7 to 2 µg L?1 for C12EO1). The developed and validated method was used in combination with liquid–liquid extraction (using ethyl acetate) in order to identify and quantitatively determine the C12OH and C12EO1–9 present in environmental samples collected from Warta river water in Poznan.  相似文献   
4.
The interaction between an ethoxylated alkylphenol polymer with formaldehyde (EAPPF) and a triblock polyEO–polyPO–polyEO copolymer (TBCP) in aqueous solutions has been investigated in detail by means of surface tension, steady-state fluorescence, dynamic light scattering (DLS) measurements and computer simulations. For comparison, the ethoxylated alkylphenol oligomer (EAPO), which is the monomer unit of EAPPF, and another nonionic water-soluble polymer PEG were also selected to get more information about the interaction between different types of surfactants and polymers. The surface properties of mixed systems at the air/water surface were evaluated from surface tension measurements. Information about the hydrophobic microenvironment and size of the aggregates was obtained from steady-state fluorescence using pyrene as a hydrophobic probe and DLS measurements, respectively. The dissipative particle dynamics simulation method was applied to simulate the interaction between EAPPF (or EAPO) and TBCP (or PEG) in aqueous solutions. The synergetic interaction between EAPPF (or EAPO) and TBCP in binary mixed solution enhanced the adsorption of surfactant molecules (EAPPF or EAPO) at the interface, while no obvious interaction between EAPPF (or EAPO) and PEG was observed.  相似文献   
5.
油墨用松香改性酚醛树脂   总被引:1,自引:0,他引:1  
叶伟荣 《上海染料》2010,38(1):38-41
文章阐述了松香改性酚醛树脂的工艺,粘度,正庚烷容纳度之间的关系,以及树脂配方,烷基酚的选择,改性的方法,工艺参数对性能的影响。  相似文献   
6.
脂肪酸甲酯乙氧基化物的物化性能研究   总被引:17,自引:4,他引:13  
对不同烷链和不同EO加合数的脂肪酸甲酯乙氧基化物的物化性能进行了测试,并对FMEE在洗衣粉中替代AEO9进行了初步研究。结果表明,与脂肪醇乙氧基化物相比,FMEE泡沫低,水溶速度快,对油脂增溶能力强,用棕榈油甲酯乙氧基化物替代AEO9在洗衣粉中应用可改善去污性能并降低成本。  相似文献   
7.
Nonylphenol is a recognized environmental contaminant, but it is unclear whether its occurrence in food arises only through environmental pathways or also during the processing or packaging of food, as there are reports that indicate that materials in contact with food such as rubber products and polyvinylchloride wraps can contain nonylphenol. A review of the literature has highlighted the scarcity of robust analytical methodology or data on the occurrence of nonylphenol in packaging materials. This paper describes a methodology for the determination of nonylphenol in a variety of packaging materials, which includes plastics, paper and rubber. The method uses either Soxhlet extraction or dissolution followed by solvent extraction (depending on the material type), followed by purification using adsorption chromatography. Procedures were internally standardized using 13C-labelled nonylphenol and the analytes were measured by gas chromatography-mass spectrometry. The method is validated and data relating to quality parameters such as limits of detection, recovery, precision and linearity of measurement are provided. Analysis of a range of 25 food-contact materials found nonylphenol at concentrations of 64–287 µg g?1 in some polystyrene and polyvinylchloride samples. Far lower concentrations (<0.03–1.4 µg g?1) were detected in the other materials. It is possible that occurrence at the higher levels has the potential for migration to food.  相似文献   
8.
利用UV/H2O2工艺对典型的烷基酚聚氧乙烯醚类物质TritonX—100(TX)进行降解,考察了不同反应条件对降解效果的影响,并且使用分子探针法测定了光解体系中羟基自由基的稳态浓度。以人类雌激素受体重组基因酵母测定其光降解过程中的雌激素效应变化,结果表明雌激素效应并未随着光解过程有较大的变化。  相似文献   
9.
为提高再生水质量和回用安全性,采用臭氧氧化壬基酚聚氧乙烯醚(NPnEO)及其代谢产物壬基酚(NP),分析了臭氧氧化NPnEO的效果及其反应历程.研究结果表明,壬基酚聚氧乙烯醚的臭氧氧化主要发生在乙氧基链上,随着氧化进程的进行,各种聚合度NPnEO中的EO链发生断裂,聚合度随之减小,前10 min内,混合物中各聚合度的NPnEO所占的比例仍符合泊松分布.壬基酚极易被臭氧氧化,接触5 min后去除率可达到90%;壬基酚的臭氧氧化不完全,有壬醇类中间产物生成.  相似文献   
10.
Methyl ester ethoxylates are a new class of ethylene oxide (EO)-derived surfactants. Little is known about the impact of structural variations on their performance properties. The effects of carbon chain length, EO content, the degree of unsaturation of the methyl ester feedstock, and feedstock purity were examined for their impact on both physical properties and surfactant performance properties. Physical properties examined included surface properties (surface tension, critical micelle concentration, surface excess adsorption), melting point, water solubility, viscosity, foam stability, color, clarity, and odor. The impact of molecular structure on performance was examined for various applications, including laundry detergents, dishwashing detergents, and hard-surface cleaners. Presented at the AOCS Annual Meeting & Expo, May 1997, Seattle, Washington.  相似文献   
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