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三聚氰胺改性脲醛树脂化学结构及反应过程的13C-NMR研究(PDF)

《南京林业大学学报(自然科学版)》[ISSN:1000-2006/CN:32-1161/S]

Issue:
2007年06期
Page:
82-86
Column:
研究论文
publishdate:
2007-06-20

Article Info:/Info

Title:
13C-NMR Spectrometry Study on Chemistry Structures and Reaction of Melamine Modified Urea-formaldehyde Resin
Article ID:
1000-2006(2007)06-0082-05
Author(s):
HAN Shu-guang WU Yu-fei LU Xiao-ning
College of Wood Science and Technology Nanjing Forestry University, Nanjing 210037, China
Keywords:
UF resin Melamine Chemical shift Chemistry structure 13C-NMR
Classification number :
TQ433
DOI:
10.3969/j.jssn.1000-2006.2007.06.019
Document Code:
A
Abstract:
The good method to analyze the structural changes of reaction process of melamine modified UF resin by the traditional process alkali-acid-alkali is 13C-NMR. It can also extrapolate potential reaction. The structure analysis indicated that, at the beginning of heat preservation, the reaction between urea and formaldehyde was an additive reaction. Main productions are monomethylolurea and dimethylolurea besides less trimethylolurea. The additive reaction between melamine and formaldehyde produced monomethylol-melamine, dimethylol-melamine. At the same time, polycondensation occurred. The polycondensations between monomethylolurea and monomethylolurea, between monomethylol-melamine and monomethylol-melamine, and between monomethylolurea and monomethylol-melamine occurred too. Main connections are methenyl ether linkage and methenyl. From the end of heat preservation to the end of whole reaction, main reaction was polycondensation. In general, there were three types reaction among melamine modified UF resin, urea-formaldehyde system, melamine-formaldehyde system and melamine-urea-formaldehyde system.

References

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Last Update: 2013-05-20