论文部分内容阅读
采用高分辨超导13C-NMR(核磁共振碳谱)法和ESI-MS(电喷雾电离质谱)法对碱性条件下模型化合物UF2(N,N′-二羟甲基脲)与M(三聚氰胺)的共缩聚反应进行了分析。研究结果表明:在UF2的反应体系中,UF2发生了一定程度的缩聚反应,产物中亚甲基醚键占主导地位;经典理论认为碱性条件下很难生成亚甲基桥键,但13C-NMR谱图中观测到化学位移为47.77×10-6、54.36×10-6和54.54×10-6处是亚甲基桥键的特征峰。在UF2/M的反应体系中,UF2大量水解并导致M羟甲基化和UF2/M的共缩聚反应;仅根据13C-NMR谱图难以确认M/UF2反应体系中发生了共缩聚反应,但结合ESI-MS谱图可以确认质荷比为221~341的对应结构是共缩聚反应产物。
High resolution superconducting 13C-NMR (nuclear magnetic resonance) and ESI-MS (electrospray ionization mass spectrometry) were used to determine the interaction between the model compounds UF2 (N, N’-dimethylolurea) and M ) Copolycondensation reaction was analyzed. The results showed that in the reaction system of UF2, UF2 polycondensation reaction to some extent, the product of methylene ether ether dominance; classical theory that the basic conditions are difficult to generate methylene bridge, but 13C- NMR spectra showed chemical shifts of 47.77 × 10-6, 54.36 × 10-6 and 54.54 × 10-6 at the methylene bridges characteristic peaks. In the UF2 / M reaction system, UF2 is greatly hydrolyzed and leads to M-methylation and UF2 / M co-polycondensation reaction; it is difficult to confirm that the copolycondensation reaction takes place in the M / UF2 reaction system only based on the 13C-NMR spectrum According to the ESI-MS spectrum, it can be confirmed that the corresponding structure with a mass-to-charge ratio of 221 to 341 is a co-condensation reaction product.