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61.
苯乙烯-马来酸酐共聚物单分子膜的静、动态性质 总被引:3,自引:0,他引:3
对不同分子量的苯乙烯-马来酸酐共聚物(PSM)单分子膜的π-A等温线、微 分曲线进行了研究,讨论了PSM单分子膜成膜过程及分子量对膜相变的影响,并用 动态膜障振动法测定了PSM单分子膜的动态弹性,结果表明,分子链的相互作用( 如卷曲和缠结)在膜的形成中起着重要的作用,并影响膜的静、动态性质,单分子 膜的动态弹性曲线有双峰,且前者比后者小,随分子量增大,膜的凝聚性、刚性和 稳定性都增强,动态弹性都增大;且分子链的相互作用对PSM单分子性质影响增大 ,压缩过程中单分子膜的相变更明显。 相似文献
62.
提供了三元乙丙橡胶(EPDM)交联的一种方法.以二甲苯为溶剂,溶液法制备马来酸酐(MAH)接枝EPDM,然后向溶液中加入适量碳酸钙(CaCO3),与已接枝的马来酸酐(MAH)反应.待反应完全后,滴加丙酮作为沉淀剂,沉淀物真空干燥,制得EPDM-g-MAH/CaCO3弹性体复合材料.溶解、溶胀及拉伸性能测试结果表明,复合材料样品已形成有效的交联,且材料的抗张强度、断裂伸长率和模量均得到较大幅度的提高,当CaCO3含量达到体系总重的20%时,复合材料呈现最佳力学性能.上述实验结果是因为碱性的CaCO3的Ca2+可以与接枝在EPDM上的MAH发生配合反应,进而成为EPDM的交联中心,形成有效交联,从而促进了EPDM机械性能的提高,ATR-FTIR和TGA的测试结果被用于证实上述观点. 相似文献
63.
Hua Xiao Bei Feng‐Li Wang Xin Yang Xu‐Jie Lu Lu‐De 《International journal of quantum chemistry》2006,106(5):1145-1152
A theoretical study of the polymerization reaction mechanism of maleic anhydride (MA) initiated by hydrate is presented. The reaction pathway has been studied with the density functional theory (DFT) method at the B3LYP/6‐311G** level. The geometrical parameters of transition states (TS) are optimized; intrinsic reaction coordinate (IRC) calculations have also been performed to obtain further credible features. Frequency analyses of all the stationary points are calculated at the same basis sets. The total energies of all geometries are corrected at second‐order Møller–Plesset (MP2)/6‐311G**. Calculation results reveal that the reaction mechanism is attributable to anion polymerization. © 2005 Wiley Periodicals, Inc. Int J Quantum Chem, 2006 相似文献
64.
R. K. Sadhir J. D. B. Smith 《Journal of polymer science. Part A, Polymer chemistry》1992,30(4):589-595
This article describes the laser-initiated copolymerization of N-vinylpyrrolidone with maleic anhydride and maleimide via charge transfer complexes. The dependence of copolymer yield on the molar ratios of the monomers in the feed and on the irradiation time is described. Based on the ultraviolet and infrared spectroscopy, and chemical analysis results, a tentative mechanism of polymerization is suggested. The rates of polymerization of several monomer systems are compared. The N-vinylpyrrolidone and maleimide system shows the highest rate of polymerization. 相似文献
65.
V. I. Terenin E. V. Kabanova N. A. Tselishcheva A. S. Ivanov N. V. Zyk 《Chemistry of Heterocyclic Compounds》2007,43(8):1038-1043
A study was carried out on the reaction of pyrrolo[1,2-a]pyrazines containing an alkyl, aryl, or aralkyl substituent at C-1
with trifluoroacetic anhydride. Trifluoroacetylation products may be formed either by reaction in the pyrrole ring or at the
aryl or aralkyl groups at C-1. Products of electrophilic substitution at C-6 are formed in the trifluoroacetylation of pyrrolo[1,2-a]pyrazines
containing at C-1 a substituent bulkier than a methyl group but lacking substituents at C-6 (the α-position of the pyrrole
ring).
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Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1226–1233, August, 2007. 相似文献
66.
Günter Eichberger Herfried Griengl Willibald Paar 《Monatshefte für Chemie / Chemical Monthly》1986,117(4):545-551
Reaction of 3-methyl-1,3-oxazolidine with phthalic anhydride in chloroform leads to ring opening and higher oligomers2 are formed. These are cleaved by addition of protic solvents and 2-methylaminoethyl hydrogenphthalate3 a is obtained. Other 1,3-oxazolidines and succinic anhydride behave similarly.
Herrn Prof. Dr. Dr. h. c.Karl Kratzl mit den besten Wünschen zum 70. Geburtstag gewidmet. 相似文献
67.
The reactions of hydrazide, mesyl hydrazide, succinyl hydrazide, and maleyl hydrazide of anthranilic acid with carbonyl compounds
were studied, and new di-and tetrahydroquinazolin-4-one derivatives were prepared. The structure of one reaction product,
viz., 3-methylsulfonylamino-2-(2-methylsulfonylaminophenyl)-1,2,3,4-tetrahydroquinazolin-4-one, was established by X-ray diffraction
study of two crystal solvates of this compound. The characteristic features of the crystal packings of these solvates are
discussed.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1183–1191, July, 2006. 相似文献
68.
在60℃和恒定离子强度下,用平衡法研究了0.004mol dm-3Cr(NO3)3在三种不同浓度顺丁烯二酸H2A(0.008,0.010,0.014mol dm-3的水溶液中的状态,用计算机拟合和p.q.r分析方法得到了[Cr(OH)A2]2-,[Cr2(OH)A2]+[Cr3(OH)2A2]+和CrA33-四种水解产物,并计算了其平衡常数,在我们系列工作中研究了在宽广的Cr3+和顺丁烯二酸浓度下Cr3+的状态,共生成11种配合物,本文对其形成规律进行了讨论. 相似文献
69.
Chemical modification of sugarcane bagasse was achieved by esterification with phthalic anhydride in pyridine after ultrasound irradiation. The parameters including ultrasonic irradiation time 0-40 min, phthalic anhydride dosage 2.5-7.5 g, reaction time 30-150 min, and reaction temperature 80-115 °C were optimised and the extent of phthalation was measured by weight percent gain. It was found that degradation of the cell wall polymers occurred at higher temperature (>90 °C) under the experimental conditions used.FT-IR and CP/MAS 13C NMR spectroscopy studies also clearly produced evidence for phthalation reaction. The phthalated bagasse preparations showed decreased thermal stability after chemical modification. 相似文献
70.
I. Strakova A. Strakovs M. Petrova S. Belyakov 《Chemistry of Heterocyclic Compounds》2007,43(12):1512-1518
The [3+2] cycloaddition reactions of a series of 1,3-substituted 5-diazo-6,6-dimethyl-4-oxo-4,5,6,7-tetrahydroindazoles with
maleic anhydride and dimethyl acetylenedicarboxylate gave 1′,3′-substituted 3-spiro[4,6-dioxo-4,6,3a,6a-tetrahydro-3H-furo[3,4-c]pyrazole]-5′-[6′,6′-dimethyl-4′-oxo-4′,5′,6′,7′-tetrahydroindazoles]
and 1′,3′-substituted 3-spiro[4,5-di(methoxycarbonyl)-3H-pyrazole]-5′-[6′,6′-dimethyl-4′-oxo-4′,5′,6′,7′-tetrahydroindazoles]
respectively. When heated the former eliminate nitrogen and are transformed into 1′,3′-substituted 6-spiro[2,4-dioxo-3-oxabicyclo[3.1.0]hexane]-5′-[6′,6′-dimethyl-4′-oxo-4′,5′,6′,7′-tetrahydroindazoles].
__________
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1784–1791, December, 2007. 相似文献