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以松香(RO)为主要原料,CaO/MgO为催化剂,与聚乙二醇(PEG)反应合成松香聚乙二醇酯(RPGE),RPGE的合成最佳条件为:n(RO):n(PEG)=1:1.6,反应温度270℃,反应时间2h.RPGE再与丙三酸合成一种新型表面活性剂——松香聚乙二醇丙三酸酯(RPGPE),RPGPE合成的最佳条件为:反应温度1... 相似文献
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以硬脂酸为基本原料,通过酰氯化后所得硬脂酰氯,再与聚乙二醇(400)进行酯化反应合成聚乙二醇(400)硬脂酸酯非离子表面活性剂。探讨了物料配比、反应时间、温度对合成反应的影响。合成反应的最佳条件为:反应温度为100℃,时间为1.0h,硬酯酰氯:聚乙二醇=1.1:1(摩尔比)。 相似文献
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双端羧基聚乙二醇的合成 总被引:6,自引:0,他引:6
用聚乙二醇和马来酸酐反应制得双端羧基聚乙二醇(CT-PEG)。讨论了原料配比、反应时间、反应温度对反应的影响。最佳工艺条件为:反应温度170℃,反应时间6h,聚乙二醇与马来酸酐的摩尔比1:2.8。 相似文献
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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。 相似文献
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以三氯氧磷、三乙胺、丙烯酸羟丙酯(HPA)等为原料,通过多步法合成了一种磷酸酯反应型乳化剂。实验对原料配比、反应时间、反应温度等进行讨论,得到最佳工艺条件,并用红外光谱对产品进行结构表征。结果表明,合成甲基丙烯酰氧丙基磷酸酯中间体,选择n(三氯氧磷)∶n(三乙胺)∶n(HPA)=1.1∶1.3∶1,反应时间为1.5h,反应温度为25℃,第二步水解反应温度0~15℃,水解物料比为n(中间体产物)∶n(三乙胺)∶n(水)=1∶1.4∶1.2时,最终产物收率最高,可达98.80%。 相似文献
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以硬脂酸为基本原料,通过酰氯化后所得脂酰氯,再与聚乙二醇(400)进行酯化反应合成聚乙二醇(400)硬脂酸酯非离子表面活性剂。探讨了物料配比、反应时间、温度对合成反应的影响。合成反应的最佳条件为:反应温度为100℃,时间为1.0h,硬酯酰氯:聚乙二醇=1.1:1(摩尔比)。 相似文献
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乙烯酮(双乙烯酮)是十分重要的化工中间体,其下游产品较多。江苏某化工厂开发生产乙烯酮(双乙烯酮)下游产品三十多个,年生产规模三万多吨,是国内以乙烯酮(双乙烯酮)为中间体生产精细化学品的综合骨干企业。针对乙烯酮(双乙烯酮)下游产品废水特点,该厂结合企业实际,开展了产品优化,结构调整,清洁生产,资源循环利用,节水降耗等工作,从源头削减了污染物的生产。同时投资二千多万元新建预处理装置三套,6000m3/d废水生化处理装置一套,使全厂乙烯酮(双乙烯酮)下游产品的废水得到了有效的治理。 相似文献
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D. G. Gordeev L. F. Gudarenko M. V. Zhernokletov V. G. Kudel’kin M. A. Mochalov 《Combustion, Explosion, and Shock Waves》2008,44(2):177-189
A semi-empirical equation of state for metals is described. Its capabilities are demonstrated by the example of the equation
of state for aluminum. New experimental data are presented on the location of the isentrope of aluminum for unloading from
the state at p = 229.71 GPa on the shock adiabat to an aerogel (SiO2) of density 0.08 g/cm3.
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Translated from Fizika Goreniya i Vzryva, Vol. 44, No. 2, pp. 61–75, March–April, 2008. 相似文献
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Jorge Marcelo Romero Soledad Bustillo Hugo Enrique Ramirez Maisuls Nelly Lidia Jorge Manuel Eduardo Gómez Vara Eduardo Alberto Castro Alicia H. Jubert 《International journal of molecular sciences》2007,8(7):688-694
A thermochemical rather simple experimental technique is applied to determine the enthalpy of formation of Diperoxide of ciclohexanone. The study is complemented with suitable theoretical calculations at the semiempirical and ab initio levels. A particular satisfactory agreement between both ways is found for the ab initio calculation at the 6–311G basis This set level. Some possible extensions of the present procedure are pointed out. 相似文献
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The objective of the study was to explore the effect of the degree of deacetylation (DD) of the chitosan used on the degradation rate and rate constant during ultrasonic degradation. Chitin was extracted from red shrimp process waste. Four different DD chitosans were prepared from chitin by alkali deacetylation. Those chitosans were degraded by ultrasonic radiation to different molecular weights. Changes of the molecular weight were determined by light scattering, and data of molecular weight changes were used to calculate the degradation rate and rate constant. The results were as follows: The molecular weight of chitosans decreased with an increasing ultrasonication time. The curves of the molecular weight versus the ultrasonication time were broken at 1‐h treatment. The degradation rate and rate constant of sonolysis decreased with an increasing ultrasonication time. This may be because the chances of being attacked by the cavitation energy increased with an increasing molecular weight species and may be because smaller molecular weight species have shorter relaxation times and, thus, can alleviate the sonication stress easier. However, the degradation rate and rate constant of sonolysis increased with an increasing DD of the chitosan used. This may be because the flexibilitier molecules of higher DD chitosans are more susceptible to the shear force of elongation flow generated by the cavitation field or due to the bond energy difference of acetamido and β‐1,4‐glucoside linkage or hydrogen bonds. Breakage of the β‐1,4‐glucoside linkage will result in lower molecular weight and an increasing reaction rate and rate constant. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 3526–3531, 2003 相似文献