林业科学2016，Vol.52Issue(1)：99-105,7.DOI:10.11707/j.1001-7488.20160112
快速固化低甲醛释放脲醛树脂的催化剂研究
Activator of Urea-Formaldehyde Resin Adhesive with Expediting Setting and Low-Formaldehyde-Emission
摘要
Abstract
[Objective]Urea-formaldehyde resin adhesive was the most widely used adhesive in the world. When the molar ratio of urea/formaldehyde reduced,the corresponding formaldehyde-emission decreased greatly,but at the same time the strength of plywood also declined dramatically. Therefore,many researches showed that the adhesives modified by melamine can effectively reduce formaldehyde-emission,and the wet strength of adhesives with low molar ratio was improved. However,low-formaldehyde-emission urea-formaldehyde resin modified by melamine resulted in extending the gel time,which cannot be solved by adding curing agent. [Method]Aiming at shortening the curing time and enhance production efficiency,different activators in urea-formaldehyde were studied by analyzing solid content,curing time,free formaldehyde content and hydroxymethyl content. DSC was applied on the dynamic analysis of curing reaction. DEA was used to investigate the resin curing process. moreover,FTIR analysis was also carried out to compare functional groups after adding different additives to select an appropriate catalyst for shorting the resin curing time and reducing formaldehyde-emission.[Result]Adding the ammonium chloride, ammonium boric acid, ammonium phosphate and ammonium sulfate respectively during addition polymerization,the curing rate of low molar ratio urea-formaldehyde resin was all improved significantly. Four kinds of activators had played an significant role in reducing the curing reaction activation energy,especially for the ammonium boric acid and ammonium sulfate. According to the results of DEA,four kinds of activators obviously accelerated resin curing,particularly for the ammonium boric acid and ammonium sulfate. After adding four kinds of activators,the strength of hot-pressing plywood almost remain unchanged and formaldehyde-emission reduced.[Conclusion]when the amount of (NH4)2SO4 was 0. 3% of the total weight during addition stage,the activation energy of the cure reaction was greatly decreased,and the curing time was also considerably reduced. Moreover, the formaldehyde emission of the plywood can meet the requirement of F****for JIS.关键词
低甲醛释放脲醛树脂合成反应催化剂/DSC/DEA/固化速度/FTIRKey words
activators for urea-formaldehyde resin with low-formaldehyde-emission/DSC/DEA/curing rate/FTIR分类
化学化工引用本文复制引用
文美玲,朱丽滨,张彦华,谭海彦,顾继友..快速固化低甲醛释放脲醛树脂的催化剂研究[J].林业科学,2016,52(1):99-105,7.基金项目
黑龙江省自然科学基金项目(C201404). （C201404）
