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叠氮二异丁基铝的构造及其缔合-解离平衡研究 总被引:1,自引:0,他引:1
叠氮二异丁基铝(DBAA)是一个新合成的化合物。通过相对分子质量的测定、氢-核磁共振谱和铝-核磁共振谱的测定,确定了DBAA三聚体的分子构造;在溶液中研究了DBAA的三聚体和单晶体之间的缔合-解离平衡。这个平衡受溶剂性质、温度的影响。借助铝-核磁共振谱和相对分子质量的测定计算了DBAA三聚体的解离平衡常数、解离焓和解离熵等热力学数据。 相似文献
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尽管叠氮二乙基铝Et2AlN3(DEAA)是一个重要的化合物,但人们对它研究还是很少的。本文通过温度-蒸气压关系研究了纯态DEAA的三聚体和单量体之间的缔合-解离平衡;通过相对分子质量测定、核磁共振氢谱和核磁共振铝谱的测定,研究了在苯和甲苯溶液中DEAA的三聚体和单量体之间的缔合-解离平衡。借助温度-蒸气压曲线分别计算了DEAA三聚体和单量体的气化焓和解离焓;通过相对分子质量测定、核磁共振铝谱测定等方法计算得到了溶液中DEAA三聚体和单量体的解离平衡常数、解离焓和解离熵等热力学数据。 相似文献
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介绍了核磁共振(NMR)波谱,尤其是核磁共振二维谱(2D NMR)在最近几年内的进展。内容包括怎样用NMR测定高聚物的序列分布、共聚物结构、聚合物的混溶性、聚合物液晶的取向度、分子量、短链度和长链支化度、凝聚态高聚物的多相结构等。 相似文献
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<正> 核磁共振二维谱是研究高聚物分子结构的有力工具.有时一张谱图,就能得到高聚物序列结构或共聚物构型的直接证据.对高聚物结构分析有重要意义.自1983年Brown首次报道聚氯乙烯的二维J谱以来.美国Macromolecules等杂志竟相报道各种聚合物的二维谱图.目前已经报道过的聚合物核磁共振二维谱有二维J谱、~(19)F-~1H异核相关谱、~(13)C-~1H异核相关谱、~1H COSY谱、~(19)F COSY谱、NOESY 相似文献
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通过Adole反应和Grigard反应合成了相应的两种立体异构的1,3,5-三-α-萘基苯. 报道了它们的UV, IR, FD-MS和NMR . 论了两种异构体的^1H NMR 和^1^3C NMR的区别. 相似文献
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Chuan-Bao Wu Jian-Yuan Hao Xian-Mo Deng Xiao-Hong Li 《Polymer Degradation and Stability》2008,93(5):932-940
A degradable polycation with high density of discrete charge was synthesized from tetraethylenepentamine (TEPA) and ethylene glycol diacrylate (EGDA) based on Michael addition and amidation. The cationic polymer synthesized here was denoted as PTE. Polymerization was monitored by 1H NMR spectroscopy. According to 1H NMR spectra, Michael addition proceeded more rapidly than amidation. After 6 h, there were no double bonds left, while amidation existed throughout the polymerization. In addition, when PTE was synthesized in chloroform and dichloromethane, respectively, there were some structural differences as shown by 1H NMR spectroscopy. The degradation laws of PTE in aqueous solution were studied by 1H NMR and viscosity measurements. When PTE was dissolved in deionized water, degradation proceeded in high velocity. However, in NaH2PO4 aqueous solution, degradation was slowered. Degradation at 37 °C proceeded obviously more rapidly than that at 25 °C. A certain degree of amidation facilitated the reduction of degradation velocity. The effect of concentration on degradation was not obvious. Interestingly, PTE synthesized in CHCl3 was degraded more rapidly than that in CH2Cl2. 相似文献
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