苯酚-尿素-甲醛树脂的合成和机理研究  

Synthesis of Phenol-urea-formaldehyde Resin and Its Reaction Mechanism

作　　者：王荣兴[1] 张祖新[1] 陈日清[1,2] 赵临五[1] 王春鹏[1,2] 储富祥[1,2] 

机构地区：[1]中国林业科学研究院林产化学工业研究所生物质化学利用国家工程实验室国家林业局林产化学工程重点开放性实验室江苏省生物质能源与材料重点实验室,江苏南京210042 [2]中国林业科学研究院林业新技术研究所,北京100091

出　　处：《林产化学与工业》2018年第1期101-109,共9页Chemistry and Industry of Forest Products

基　　金：“十二五”国家科技支撑计划资助(2015BAD14B03);木竹产业技术创新战略科研计划课题资助(TIAWBI201506)

摘　　要：制备合成了不同尿素用量的系列尿素改性酚醛(PUF)树脂胶黏剂,探讨了一种PUF树脂胶黏剂较优的配方和合成工艺,并通过^(13)C NMR、TG对PUF树脂的反应过程和分解过程进行了研究。结果表明:合成过程中尿素分三批加入,以CaO和NaOH为复合催化剂,在碱性条件下制备的5组尿素用量不同的PUF树脂,以这5组PUF树脂作胶黏剂压制的杨木三合板胶合强度全部符合Ⅰ类胶合板要求,甲醛释放量≤0.5 mg/L;^(13)C NMR分析结果显示,树脂合成过程中的羟甲基、亚甲基、亚甲基醚键的含量随着尿素添加量和反应时间的不同而变化,PUF树脂合成过程的主要反应为甲醛的亲电加成,TG分析表明热稳定性呈先提高后降低的趋势。Phenol-urea-formaldehyde （PUF） resin wood adhesives with different amount of urea instead of phenol were synthesized, and a simple phenol-urea-formaldehyde resin formulation and synthesis technology was investigated. The bonding strength of the five PUF pressed plywoods with different dosage of urea all met the requirements of class I. The cure, decomposition and reaction processes of PUF resin were characterized byl3C NMR and TG respectively.13C NMR showed the content of hydroxymethyl, methylene and methylene ether bonds in PUF resin varied with the amount of urea and the reaction time during the preparation. Furthermore, the reaction mechanism of PUF synthesis was analyzed and the heat resistance of the synthesized PUF resin was characterized by TG. The results showed that the synthesis process of PUF resin was the electrophilic addition of formaldehyde and the thermostability firstly increased and subsequently reduced.

关 键 词：尿素改性酚醛树脂 木材胶黏剂 反应机理 残炭率 胶合强度 

分 类 号：TQ35[化学工程]