利用时域核磁共振研究脲醛树脂的固化过程

波谱学杂志

利用时域核磁共振研究脲醛树脂的固化过程

邵朱伟，张明辉，李新宇*

内蒙古农业大学材料科学与艺术设计学院，内蒙古呼和浩特 010018

收稿日期:2013-10-16 修回日期:2014-07-17 出版日期:2014-09-05 发布日期:2014-09-05
作者简介:邵朱伟(1989-)，男，辽宁铁岭人，硕士研究生，材料加工工程专业，E-mail: 570168719@qq.com. *通讯联系人：张明辉，电话：15849376426，E-mail: zhangmh_email@aliyun.com.
基金资助:
国家自然科学基金资助项目(30800866，31160141)．

Curing Process of Urea-Formaldehyde Resin Studied by Time-Domain Nuclear Magnetic Resonance

SHAO Zhu-wei，ZHANG Ming-hui，LI Xin-yu*

College of Material Science and Art Design, Inner Mongolia Agricultural University, Huhhot 010018, China

Received:2013-10-16 Revised:2014-07-17 Online:2014-09-05 Published:2014-09-05
About author:*Corresponding author：ZHANG Ming-hui, Tel: 15849376426，E-mail: zhangmh_email@aliyun.com.
Supported by:
国家自然科学基金资助项目(30800866，31160141)．

摘要/Abstract

摘要：

利用时域核磁共振(TD NMR)技术对无固化剂的脲醛树脂在不同温度下固化过程进行了研究，实验结果表明：脲醛树脂在120 ℃左右时开始固化，在180 ℃左右时固化反应基本结束．随着温度的升高，自旋-自旋弛豫时间(T2)的总峰面积逐渐减少，当温度高于140 ℃时，总峰面积减少的程度较大．在30 ℃~140 ℃温度范围内，自旋-晶格弛豫时间T₁(1) = 0.014 ms 时，随着温度的升高，峰面积先逐渐减少而后略微增加；T₁(2) = 327.455 ms 时，随着温度的升高，峰面积逐渐减少．在30 ℃~180℃温度范围内，自旋-晶格弛豫时间(T₁)分布的总峰面积随着温度的升高而逐渐减少．在固化过程中，随着温度的升高，脲醛树脂体系的质量逐渐减少，说明脲醛树脂胶黏剂体系发生了缩聚交联反应，同时生成了甲醛和水．

关键词: 时域核磁共振(TD NMR), 固化, 自旋-自旋弛豫时间(T₂), 自旋-晶格弛豫时间(T₁), 脲醛树脂

Abstract:

The curing process urea-formaldehyde resin without the use of hardeners was studied by time-domain nuclear magnetic resonance (TD NMR) at different temperatures. The results showed that urea-formaldehyde resin started curing at about 120 ℃ and ended around 180 ℃. The total peak area for T₂decrease gradually with increasing temperature; and larger changes were observed when the temperature was above 140 ℃. At temperature range between 30 ℃ to 140 ℃, the peak areas decreased gradually and then increased slightly with increasing temperature at T₁(1) = 0.014 ms; the peak areas decreased gradually with increasing temperature at T₁ (2) = 327.455 ms. The total peak area for T₁ decrease gradually with increasing temperature between 30 ℃ and 180 ℃. The urea-formaldehyde resin system weight decreased gradually with increasing temperature in the solidification process, confirming that cross-linking condensation reaction may occur, giving off formaldehyde and water.

Key words: time-domain nuclear magnetic resonance, solidification, spin-spin relaxation time, spin-lattice relaxation time, urea-formaldehyde resin

中图分类号:

O482.53

邵朱伟，张明辉，李新宇*. 利用时域核磁共振研究脲醛树脂的固化过程[J]. 波谱学杂志.

SHAO Zhu-wei，ZHANG Ming-hui，LI Xin-yu*. Curing Process of Urea-Formaldehyde Resin Studied by Time-Domain Nuclear Magnetic Resonance[J]. Chinese Journal of Magnetic Resonance.

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