大豆蛋白-三聚氰胺-尿素-甲醛树脂胶黏剂固化剂的研究

以大豆蛋白降解液、三聚氰胺、尿素和高浓度甲醛为原料,合成了一种低摩尔比的大豆蛋白-三聚氰胺-尿素-甲醛共缩聚树脂胶黏剂(SMUF)。选用(NH4)2SO4、(NH4)2S2O8、(NH4)2HPO4和H3PO4作为SMUF树脂的固化剂,研究了固化剂对SMUF树脂基本理化性能的影响。结果表明:1)传统固化剂(NH4)2SO4不能使SMUF树脂充分固化,最终树脂胶合强度低、耐水性差,固化后的胶层断面疏松、多孔;2)H3PO4和(NH4)2S2O8属于中强酸体系,两者均能一定程度加速SMUF树脂的固化,树脂胶合强度和耐水性均得到改善,固化温度显著降低,固化放热量有所提高;3)(NH4)2HPO4是一种缓冲型酸,其催化SMUF树脂的固化速度较为均匀,树脂综合性能较优,树脂的胶合强度和耐水性较好,固化温度也有所降低,树脂交联程度高,树脂固化层断面相对较为均匀。

Development of Curing Agent of Soy Protein-Melamine-Urea-Formaldehyde (SMUF) Resin

A soy protein-melamine-urea-formaldehyde resin with lower molar ratio was prepared by using soy protein degradation fluid,melamine,urea and high concentration formaldehyde.(NH 4) 2SO 4,(NH 4) 2S 2O 8,(NH 4) 2HPO 4 and H 3PO 4 were as used to investigate the effect of these curing agents on the basci phycial-chemcial properties of SMUF resin.The results showed that 1)(NH 4) 2SO 4 could not fully cure SMUF resin,the resultant resin had lower bonding strength,inferior water resistance,and loose and porous curing interface.2) H 3PO 4 and (NH 4) 2S 2O 8 belonged to medium strong acid system,they could accelerate the curing speed of SMUF resin in some extents.The bonding strength and water resistance were improved,although curing temperature decreased significantly,curing exothermic value increased.3)(NH 4) 2HPO 4 was a buffering acid,the curing speed was very uniform.The resin performances,bonding strength,and water resistance were better.The curing temperature was lower and the resin curing interface was uniform.