摘要
研究了在弱酸-弱碱-弱酸条件下,加入改性剂合成脲醛(UF)树脂胶的工艺过程。实验结果表明,甲醛与尿素的配比[即n(F)/n(U)比值]、体系pH值、尿素的加料方式和改性剂对UF树脂胶中游离甲醛的含量和胶合强度有很大的影响;当n(F)/n(U)=1.06、缩聚反应阶段体系的pH值为4.75～4.80、尿素分3批加入、反应温度为90℃、加入适量的聚乙烯醇(PVA)和三聚氰胺改性剂时,制得的UF树脂胶中游离甲醛的含量不大于0.10%(符合GB/T14 074.16-1993标准中的指标要求)、粘接强度为4.70 MPa且综合性能优良。
The synthetic technology process of urea-formaldehyde （UF） resin adhesives with modifier was studied under the condition of subacidity-alkalescence-subacidity. The experiment results showed that the influence of the mole ratio of formaldehyde and urea [namely n（F）/n（U） ratio], pH value of system, adding urea wise and modifier on free formaldehyde content and agglutinative strength of UF resin were great. The mass fraction of free formaldehyde content was less than 0.10%（met request of GB/T 14 074.16-1993） in UF resin adhesive ,the agglutinative strength was 4.70 MPa, and integration performance was better when n（F）/n（U ） ratio was 1.06, the pH value of system was between 4.75 and 4.80 in polycondensation reaction stage, urea was appended for three times, reaction temperature was 90 ℃, content of PVA and melamine-modifier were right amount.
出处
《中国胶粘剂》
CAS
2008年第8期5-8,共4页
China Adhesives
基金
西安工业大学校长基金(XAGDXJJ0610)
关键词
脲醛树脂
胶粘剂
游离甲醛
胶合强度
urea-formaldehyde resin
adhesive
free formaldehyde
agglutinative strength
