摘要
UF(脲醛树脂)胶粘剂在木材工业中应用广泛,但其在生产和使用过程中会持续释放出危害环境和人体健康的游离甲醛。采用降低n(甲醛)/n(尿素)比例和使用传统固化剂氯化铵时,虽可降低UF胶粘剂的游离甲醛含量,但其固化速率较小、粘接强度较低。以过硫酸铵、多官能团物质(G)、甲酸、氯化铵及其不同复合物等分别作为UF的固化剂,采用单因素试验法优选出制备改性UF胶粘剂的最佳工艺条件。研究结果表明:当p H=5.5、w(氯化铵)=3%和w(G)=0.6%(均相对于UF质量而言)时,改性UF胶粘剂的粘接强度(为1.95 MPa)相对最大、适用期(为8 h)相对较长且游离甲醛含量相对较低。
UF(urea-formaldehyde resin)adhesive is widely used in wood industry,but in the process ofproduction and use,it will continuously release the free formaldehyde,which will damage the environment and the human health.Although the free formaldehyde content in UF adhesive can be decreased,but its curing speed andbonding strength were lower when molar ratio of formaldehyde to urea was lower,and ammonium chloride was used astraditional curing agent.With ammonium persulfate,polyfunctional group-substance(G),formic acid,ammoniumchloride,and their different compounds respectively as UF's curing agents,the optimal process conditions ofpreparing modified UF adhesive were preferred by single-factor experiment.The research results showed that themodified UF adhesive had the relatively maximal bonding strength(1.95 MPa),the relatively longer workinglife(8 h),and the relatively lower free formaldehyde content when p H value was 5.5,and mass fractions ofammonium chloride and G were 3% and 0.6% respectively in UF.
出处
《中国胶粘剂》
CAS
北大核心
2018年第2期7-10,共4页
China Adhesives
基金
国家科技支撑计划课题(2011BAE19B02)
中石化委托开发项目(LZ10018)
关键词
胶粘剂
脲醛树脂
固化剂
粘接强度
游离甲醛
adhesive
urea-formaldehyde resin(UF)
curing agent
bonding strength
free formaldehyde
