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991.
A biodegradable poly(ester amide) resin was synthesized from N,N-bis(2-hydroxy ethyl) fatty amide of castor oil with maleic anhydride, phthalic anhydride and isophthalic acid (100:30:35:35 mole ratio) by the polycondensation process. The fatty amide of the oil was obtained for the first time with 95% yield. The chemical structure of the synthesized resin was characterized by spectroscopic techniques like FTIR, 1H NMR and 13C NMR. Various physical properties such as acid value, saponification value, iodine value, specific gravity and viscosity of the resin were also determined. Further the rheological behavior, studied in the steady shear mode showed shear thinning behavior of the resin. The epoxy cured poly(ester amide) thermoset using poly(amido amine) hardener exhibited better properties than with the cycloaliphatic amine hardener cured system. TGA studies also revealed higher thermal stability of the former system than the latter. In vitro-biodegradation study of the poly(ester amide) thermoset using Pseudomonas aeruginosa and Bacillus subtilus bacteria revealed superior biodegradability of the thermoset using the former bacterial strain. Excellent chemical resistance against various chemical media including alkali was observed for epoxy-poly(amido amine) cured poly(ester amide) resin over epoxy-cycloaliphatic amine one. The epoxy-poly(amido amine) cured poly(ester amide) thermoset thus has the potential to be used as surface coating material. 相似文献
992.
The preparations of quaternary ammonium compounds from various tertiary amines and the (environmentally friendly) alkylation
agent dimethyl carbonate were carried out. The effects of reaction temperature, reaction time, material mol ratio and solvent
dosage on quaternization were examined, and the optimum reaction conditions were determined. Under the optimum conditions,
the conversions of mono-alkyl tertiary amines could attain over 99%, while the conversions of di-alkyl tertiary amines reached
over 95%. Moreover, a series of quaternary ammonium salts with new counterions (HCO3, CH3COO, CH3CH2COO, CH3CH(OH)COO) were synthesized by the hydrolysis of methyl carbonate quaternary ammonium salts or by ion exchange reaction of
methyl carbonate quaternary ammonium salts with corresponding acids. 相似文献
993.
Jia-Heng Lei Hui Li An-Fu Zhang Xiao-Di Du Qian Lu 《Journal of surfactants and detergents》2012,15(1):117-121
In the extraction system of ethyl acetate and NaCl aqueous solution, partition coefficients of polyethylene glycol mono-acrylate
(PEGmA) and polyethylene glycol di-acrylate (PEGdA) varied with temperature and concentration of NaCl solution were studied.
The best separation condition of PEGmA and PEGdA was determined on that basis. Results of the testing showed that partition
coefficients of PEGmA and PEGdA sharply increased with rising concentration of NaCl solution and temperature. Since the incremental
degrees of PEGmA and PEGdA were different from each other, the ratio of partition coefficient (K
PEGdA/K
PEGmA) reached a maximum under the conditions of 20 °C and 5 mol L−1 NaCl. The best separating condition was as follows: PEGdA was extracted out with ethyl acetate by adding 5 mol L−1 NaCl at 20 °C. After three repetitions, the recovery rate of PEGdA reached 99.8%. The water phase was heated to 50 °C and
PEGmA was extracted out with ethyl acetate. The recovery rate of PEGmA amounted to 68.8% by three repetitions. After washing
and drying, the purity of PEGmA and PEGdA was 99.7 and 98.7% respectively. 相似文献
994.
An iridium catalyst – stabilized by an anionic P,N ligand – was used for the symmetrical and unsymmetrical monoalkylation of para‐, meta‐, and ortho‐benzenediamines. Benzyl and aliphatic alcohols were used as alkylating reagents. 28 derivatives were synthesized. 14 of them are new compounds. Furthermore, the alkylation of the pharmacological important diamine Dapson® (dapsone) is described. 14 dapsone derivatives were synthesized among them 9 new compounds. 相似文献
995.
Subhash Chandra Ghosh Joyce S. Y. Ngiam Christina L. L. Chai Abdul M. Seayad Tuan Thanh Dang Anqi Chen 《Advanced Synthesis \u0026amp; Catalysis》2012,354(8):1407-1412
A practical and efficient method for the synthesis of amides has been developed by iron‐catalysed oxidative amidation of aldehydes with amine hydrochloride salts. A wide range of amides have been obtained in good to excellent yields under mild conditions. The application of this novel amide formation reaction to the synthesis of pharmaceutical compounds has been successfully demonstrated. 相似文献
996.
聚醚胺页岩抑制剂抑制性能研究 总被引:1,自引:0,他引:1
以聚醚胺为钻井液用页岩抑制剂,通过相对抑制率实验、抑制膨润土造浆实验考察了其页岩抑制性能.结果表明,聚醚胺浓度越大,相对抑制率越高,浓度大于0.5%时,相对抑制率不再变化,抑制性能优于5% KCl.抑制膨润土造浆实验中,浓度越高,动切力越小,抑制造浆能力越强.加入聚醚胺的泥浆在100~180 ℃下老化16 h后,相对抑制率均在90%以上,抗温性能良好.加入不同浓度的NaCl(1%~36.5%)或CaCl2(1%~5%)老化16h后,流变参数变化不大,相对抑制率均在95%以上,抗盐性能良好. 相似文献
997.
998.
彭磊 《化学推进剂与高分子材料》2012,10(6):43-46
将二茂铁基超支化聚(胺)酯(HPAE-Fc)添加到端羟基聚丁二烯(HTPB)中老化,通过紫外分光光度计测定了HTPB基体中二茂铁基团含量,并计算了HPAE-Fc迁移率,与二茂铁、叔丁基二茂铁的迁移率进行了对比.研究结果表明:HPAE-Fc的迁移率远低于二茂铁、叔丁基二茂铁,迁移率随着相对分子质量的增大而减小,迁移率由高到低的顺序为二茂铁、叔丁基二茂铁、HPAE-Fc;各物质的迁移率随时间延长或温度提高而增加.实验结果表明:与二茂铁和叔丁基二茂铁相比,HPAE-Fc在HTPB中具有较强的抗迁移性能.HPAE-Fc在HTPB中抗迁移性的机理为高的相对分子质量、化学组成与结构、较强的分子间作用力、良好的相容性和与HTPB形成氢键等因素共同作用的结果. 相似文献
999.
对1,1′-二茂铁二羧酸二辛酯的合成方法开展了研究.通过二茂铁的Friedel-Crafts酰基化反应合成了1,1′-二乙酰基二茂铁,然后用次氯酸钠氧化1,1′-二乙酰基二茂铁得到1,1′-二茂铁二甲酸.研究了1,1′-二茂铁二甲酸直接酯化法制备1,1′-二茂铁二甲酸二甲酯,以其为原料通过酯交换的方法可以65%的收率和四步合计48%的总收率实现1,1′-二茂铁二甲酸二辛酯的合成,产物结构用1H-NMR、IR进行了表征. 相似文献
1000.