摘要
异氰酸酯基与木材和水在一定条件下生成氨基甲酸酯和取代脲的反应是端异氰酸酯聚氨酯胶粘剂与木材胶接的基础反应。然而对于多异氰酸酯与木材的反应产物生成氨基甲酸酯和取代脲的分离及定量一直是该领域的研究难点。基于傅利叶红外光谱和凯氏定氮方法,并采用单官能度的苯基异氰酸酯(PI),文中提出并证明了一种能将取代脲从氨基甲酸酯中分离出来的方法,由此可以对苯基异氰酸酯/木材的各反应产物进行准确定量。研究表明,含水率、时间、温度等反应条件对异氰酸酯/木材反应中的氨基甲酸酯和取代脲的生成量有不同的影响。
The reactions of isocyanate with wood and with water in wood to form the urethane and the urea, respectively, are basic for understanding the adhesion of isocyanate-terminated polyurethane resins to wood. However, it is still a sticking point for separating urethane from urea in isocyanate- wood reacted resultant. Based on FT-IR analyses and nitrogen content analyses by Kjeldahl method in combination of using mono-isocyanate, the paper proposed and confirmed a separation technique, by which the urea was adequately separated from the urethane, and therefore it was able to quantitatively determine their contents within isocyanate-wood reacted resultants. It indicates that the reaction conditions, such as moisture content, temperature and time, have some effects on the contents of the urethane and urea formed in isocyanate-wood reaction systems.
出处
《高分子材料科学与工程》
EI
CAS
CSCD
北大核心
2008年第11期130-133,共4页
Polymer Materials Science & Engineering
基金
中国教育部博士基金(20050225011)
黑龙江博士后科学-研究基金(LBH-Q05011)
东北林业大学创新基金
关键词
聚氨酯
木材
FT-IR光谱
分离方法
定氮
polyurethanes
wood
FT-IR
separation techniques
nitrogen content analysis
