文献类型：期刊文献

中文题名：E_1级胶合板用脲醛树脂的^(13)CNMR定量分析

英文题名：Quantitative ^(13)C NMR Analysis of Urea-formaldehyde Resin for E_1-type Plywood

作者：金立维[1] 王春鹏[1] 周道兵[1] 储富祥[1] 赵临五[1]

第一作者：金立维

机构：[1]中国林业科学研究院林产化学工业研究所,国家林业局林产化学工程重点开放性实验室

年份：2006

期号：4

起止页码：6-10

中文期刊名：林产化学与工业

外文期刊名：Chemistry and Industry of Forest Products

收录：CSTPCD;;EI(收录号：20070510401557);Scopus(收录号：2-s2.0-33846489598);CSCD:【CSCD_E2011_2012】；

基金：国家杰出青年科学基金资助项目(30325031);科技部农业科技成果转化资金资助项目(03EFN216700299);国家林业局林业科学技术推广项目(竹材专用胶黏剂开发及技术示范)

语种：中文

中文关键词：脲醛树脂;羟甲基脲;亚甲基醚;胶合板

外文关键词：urea-formaldehyde resin;hydroxymethylurea;methylene-ether;plywood

分类号：TQ323;TQ433

摘要：采用13CNMR定量分析了由选定碱-酸-碱工艺所合成的E1级胶合板用脲醛树脂。结果表明:在初始碱性阶段有70.27%的甲醛分子转化成了羟甲基脲,24.83%的甲醛分子转化成了亚甲基醚键。在随后的酸性缩聚阶段中,64%的羟甲基脲发生断裂,放出甲醛,缩聚成亚甲基键及亚甲基醚键。在酸性阶段加入的第二批尿素与树脂中的游离甲醛形成羟甲基脲。超过一半的亚甲基醚键在最后的碱性保温阶段发生分解,并与此时加入的第三批尿素生成羟甲基脲。
The urea-formaldehyde (UF) resins for E_1-type plywood synthesized by specific procedure were quantitatively examined by the ~ 13 C NMR spectroscopy. It was proved that 70.27% of formaldehyde molecules were transformed into hydroxy- methylurea and 24.83% formaldehyde molecules were transformed into methylene-ether bond during the initial alkaline reaction stage(pH value 7.2-[KG-*6]7.8). About 64% of hydroxymethyl groups formed in the initial alkaline reaction stage were polymerized during the subsequent acidic reaction stage(pH value 5.4-[KG-*6]5.6)by forming methylene or methylene-ether bonds and releasing some formaldehyde. The free formaldehyde of resin could react with the second dosage of urea during the next acidic reaction stage(pH value 6.5-[KG-*6]6.9) to form hydroxymethylureas. More than half of methylene-ether bonds were decomposed during the last alkaline cooling stage(pH value 7.5-[KG-*6]8.0)and reacted with the third dosage of urea to form hydroxymethylurea.