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首页> 外文期刊>Journal of Applied Polymer Science >A C-13-NMR ANALYSIS METHOD FOR MF AND MUF RESINS STRENGTH AND FORMALDEHYDE EMISSION FROM WOOD PARTICLEBOARD .1. MUF RESINS
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A C-13-NMR ANALYSIS METHOD FOR MF AND MUF RESINS STRENGTH AND FORMALDEHYDE EMISSION FROM WOOD PARTICLEBOARD .1. MUF RESINS

机译：木材刨花板中MF和MUF树脂强度和甲醛释放量的C-13-NMR分析方法1。 MUF树脂

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摘要

A method based on the use of C-13-NMR relative peak intensity ratios for different characteristic chemical groups, known or supposed to contribute to melamine-urea-formaldehyde (MUF) resin strength and formaldehyde emission, is presented. The method relates results obtained by C-13-NMR analysis of liquid MUF resins with their strength and formaldehyde emission in the resin hardened state. Sets of correlation equations are presented which can be used to predict some of the physical properties of a hardened MUF resin by studying the C-13-NMR peak ratios of well-defined chemical groups in the liquid MUF resin. A true class of MUF resins, with characteristics all of their own, appear only to exist in the copolymers in which the mass ratio of M : U is in the approximate range 55 : 45 to 34 : 66, mass ratios outside this range resulting in resins which behave almost as pure melamine or as pure urea resins. Contrary to what was found for MUF glue mixes in which lower condensation pre-resins are used as scavengers and accelerators, in pure MUF resins, the ratios of NMR peaks of the downfield substituted and unsubstituted triazine and urea signals, while still important, do not exclusively dominate the correlation equations, other chemical groups such as methylene (Me), methylol (Mo), and methylene ether groups assuming considerable importance. (C) 1996 John Wiley & Sons, Inc. [References: 25]
机译：提出了一种基于C-13-NMR相对峰强度比的不同特征化学基团的方法，已知或认为该特征基团有助于三聚氰胺-脲-甲醛（MUF）树脂强度和甲醛释放。该方法涉及通过液态MUF树脂的C-13-NMR分析获得的结果，以及它们在树脂硬化状态下的强度和甲醛释放量。提出了一组相关方程，通过研究液态MUF树脂中定义明确的化学基团的C-13-NMR峰比，可用于预测硬化的MUF树脂的某些物理性质。真正具有其全部特征的MUF树脂似乎仅存在于M：U的质量比在55:45至34:66的范围内的共聚物中，超出该范围的质量比导致几乎表现为纯三聚氰胺或纯脲树脂的树脂。与使用低缩合预树脂作为清除剂和促进剂的MUF胶混合物相反，在纯MUF树脂中，低场取代的和未取代的三嗪和尿素信号的NMR峰比虽然仍然很重要，但并不重要仅在相关方程中占主导地位，其他化学基团（例如亚甲基（Me），羟甲基（Mo）和亚甲基醚基团）具有相当重要的地位。 （C）1996 John Wiley＆Sons，Inc. [参考：25]

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