摘要
对不同固化体系下低毒脲醛树脂以及其与封闭异氰酸酯反应的固化速度、适用期及pH值变化情况进行了研究。结果表明,单组分固化体系中,硫酸铝固化速度最快。磷酸与氯化铵组成的双组分固化体系,固化速度虽然很快,但适用期较短;乌洛托品对延长脲醛树脂胶的适用期效果较好。加入封闭异氰酸酯后会加快脲醛树脂固化速度,但其适用期有所缩短,而在硫酸铝和磷酸的固化体系中不明显。pH值在15 min内下降较快,30 min之后趋于稳定。
Gelation time, pot life and pH value of the low-toxicity urea-formaldehyde （UF） resins containing blocked isocyanate during curing were studied in different curing systems. In single curing system, the gelation time is the most quick for aluminium sulfate. In binary curing system of phosphate and ammonium chloride, although the gelation time is fast, but the pot life is short, urotropine is excellent for prolonging pot life. When adding blocked isocyanate,it will accelerate the gelling reaction of UF, but shorten the pot life, and the phenomenon is not evidence in aluminium sulfate and phosphate, pH value dropped quickly during 15 minutes and it went to stabilization after 30 minutes.
出处
《粘接》
CAS
2008年第3期1-4,共4页
Adhesion
基金
教育部博士点基金项目(项目号:20050225011)
关键词
固化体系
脲醛树脂
封闭异氰酸酯
curing system
urea-formaldehyde resin
blocked isocyanate
