Study on the evolvement of structure in synthesis of urea-formaldehyde resins by FTIR

被引：24

作者：

Li Ai-Ping

Kan Cheng-You

Du Yi

Liu De-Shan ^{[1
]}

机构：

[1] Tsinghua Univ, Dept Chem Engn, Beijing 100084, Peoples R China

[2] Tsinghua Univ, Key Lab Adv Mat, Minist Educ, Beijing 100084, Peoples R China

来源：

ACTA PHYSICO-CHIMICA SINICA | 2006年 / 22卷 / 07期

关键词：

urea-formaldehyde resin; structure; FTIR;

D O I：

10.3866/PKU.WHXB20060721

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

By means of Fourier transform infrared (FTIR) spectroscopy, the structure development of urea-formaldehyde (UF) resins in synthesis process was investigated, and the structural difference of reaction inter-products of urea and formaldehyde was observed in alkaline and acidic media and at different formaldehyde-to-urea molar ratios. With the reaction process of urea and formaldehyde the variation of the FTIR peaks was obvious, the amide II band frequency of FTIR spectra of UF resins shifted gradually from high to low, and more methylols, ether linkages and -NHCH2- were formed. But in the cured UF resins, the contents of methylols, ether linkages, and -NHCH2- decreased. With the increase of the formaldehyde-to-urea molar ratios from 0.5 to 3.0, the amide 11 band frequency also shifted gradually from high to low, and the contents of ether linkages and -NHCH2- increased in alkaline media, while in stronger acidic media the contents of Uron, methylene linkages, and methylols increased, but the content of -NHCH2- decreased.

引用

页码：873 / 877

页数：5

共 8 条

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