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A new synthesis of poly(amido-amine)s from bis (secondary amine)s and acryloyl chloride has been studied, leading to polymers in which the amido- and amino-groups are randomly arranged along the macromolecular chain. A poly(amido-amine) based on piperazine, chosen as the mother compound, has been fully characterized by 13C n.m.r. as well as by identification and quantitative evaluation of its hydrolysis products. 相似文献
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为制备一种对染色废水有显著脱色效果的絮凝剂,采用溶液聚合法,将两种阳离子单体二甲基二烯丙基氯化铵(DMDAAC)和丙烯酰氧乙基三甲基氯化铵(DAC)分别与丙烯酰胺(AM),丙烯酸(AA)共聚,合成了两性聚合物。研究了阳离子单体种类和引发体系对两性聚合物合成的影响,单体配比对合成产物特性黏数[η]的影响,确定了合适的制备条件:以AM、AA和DAC为单体,过硫酸铵为引发剂,单体的质量比为AM:AA:DAC=6:2:4、体系pH为6.5。探讨了聚合物的用量、阴阳离子比例以及染色废水的温度、pH对脱色效果的影响。结果表明,所制备的两性聚合物,对皮革染色废水的脱色率达92%以上。常温(25℃)条件下,合成产物对皮革染色废水脱色的较佳pH值为3~4。 相似文献
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高效液相色谱法测定竹筷中噻苯咪唑、邻苯基苯酚和联苯 总被引:1,自引:0,他引:1
建立高效液相色谱测定竹筷中噻苯咪唑、邻苯基苯酚、联苯的方法。以甲醇为提取溶剂,用索氏提取法提取竹筷中噻苯咪唑、邻苯基苯酚和联苯3种保鲜剂。以甲醇-水(体积比70:30)为流动相,流速1.0mL/min,采用C18柱(250mm×4.6mm,5μm)分离,紫外检测器检测,检测波长247nm,进样量20μL。方法的相关系数均大于0.999,最低检出限为0.01μg/mL,平均回收率为95.8%~97.1%,相对标准偏差为1.4%~2.6%。应用所建立的方法测定一次性竹筷中噻苯咪唑、邻苯基苯酚、联苯的残留量,结果表明:该方法样品处理简单,色谱分离完全,结果准确可靠,适于竹筷中噻苯咪唑、邻苯基苯酚和联苯的分析检测。 相似文献
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Structure, properties and application to water-soluble coatings of complex antimicrobial agent Ag-carboxymethyl chitosan-thiabendazole 总被引:3,自引:0,他引:3
The structure, properties and application to water-soluble coatings of a new complex antimicrobial agent Ag-carboxylmethyl citosan-thiabendazole (Ag-CMCTS-TBZ) prepared from different materiel ratios were reported. The silver ions were preferably coordinated with the free-NH2 groups and the -OH groups of secondary alcohol and carboxyl in CMCTS. TBZ preferably bonded to carboxyl group in CMCTS by electrostatic force and hydrogen bonding. Increase in silver ions content in the complex agent improved to some limited extent the antibacterial activity, but enhanced coloring and cost of the complex agent. Increase in TBZ content resulted in increase of antifungal activity, but decrease of water solubility of the complex agent. The antimicrobial MICs of the complex agent to Esherichia coil, Staphylococcus aureus, Candida albicans, Aspergillus niger, Mucor sp. were 20 -80, 15 -60, 20 - 55, 40 - 250, and 400 - 1700 mg/kg, respectively. Addition of 0.1% of this complex agent to acrylic emulsion paint made the paint without substantial change in color, luster, viscosity, odor or pH value, but with an excellent and chronically persisting broad-spectra antimicrobial activity. 相似文献
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The binding of orally dosed hydrophobic active pharmaceutical ingredients to casein micelles in milk
Casein proteins (αS1-, αS2-, β- and κ-casein) account for 80% of the total protein content in bovine milk and form casein micelles (average diameter = 130 nm, approximately 1015 micelles/mL). The affinity of native casein micelles with the 3 hydrophobic active pharmaceutical ingredients (API), meloxicam [351.4 g/mol; log P = 3.43; acid dissociation constant (pKa) = 4.08], flunixin (296.2 g/mol; log P = 4.1; pKa = 5.82), and thiabendazole (201.2 g/mol; log P = 2.92; pKa = 4.64), was evaluated in bovine milk collected from dosed Holstein cows. Native casein micelles were separated from raw bovine milk by mild techniques such as ultracentrifugation, diafiltration, isoelectric point precipitation (pH 4.6), and size exclusion chromatography. Acetonitrile extraction of hydrophobic API was then done, followed by quantification using HPLC-UV. For the API or metabolites meloxicam, 5-hyroxy flunixin and 5-hydroxy thiabendazole, 31 ± 3.90, 31 ± 1.3, and 28 ± 0.5% of the content in milk was associated with casein micelles, respectively. Less than ~5.0% of the recovered hydrophobic API were found in the milk fat fraction, and the remaining ~65% were associated with the whey/serum fraction. A separate in vitro study showed that 66 ± 6.4% of meloxicam, 29 ± 0.58% of flunixin, 34 ± 0.21% of the metabolite 5-hyroxy flunixin, 50 ± 4.5% of thiabendazole, and 33 ± 3.8% of metabolite 5-hydroxy thiabendazole was found partitioned into casein micelles. Our study supports the hypothesis that casein micelles are native carriers for hydrophobic compounds in bovine milk. 相似文献
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With the increased awareness of avoiding residue metals, the field of organocatalysts is attracting more attention. Aliphatic tertiary amines, such as triethylamine (TEA), N, N, N, N‐tetramethylethylenediamine (TMEDA) and 1,1,4,7,7‐pentamethyldiethylenetriamine (PMDTA), have low boiling points which allow their easy elimination after a chemical reaction. Here, we used these aliphatic tertiary amines to catalyze ring‐opening polymerizations (ROPs) of trimethylene carbonate (TMC). In the presence of benzyl alcohol, the catalytic activities of the tertiary amines were in the order of TEA < TMEDA < PMDTA. Correlation between the molecular weight of polycarbonates and monomer conversions was linear, suggesting the polymerization was controlled. The polymerization pathway was presumed to follow an alcohol‐activated mechanism according to the end‐group fidelity determined using 1H NMR spectroscopy. The ROP of TMC was also successfully initiated by PEO99‐PPO65‐PEO99 (F127) under the catalysis of the tertiary amines, producing well‐defined PTMCn‐F127‐PTMCn copolymers with narrow dispersity ( ca 1.2) and with thermosensitive properties in aqueous solution. Furthermore, copolymerizations of TMC with acryloyl‐containing cyclic carbonate were catalyzed by the tertiary amines in the presence of F127. No crosslinking reactions were detected. Our results demonstrate that the aliphatic tertiary amines have the potential to catalyze TMC homo‐ or copolymerization featuring controllable structure and composition under mild conditions. Copyright © 2012 Society of Chemical Industry 相似文献