Abstract:

A kind of active reagent that could reduce the cost of urea-formaldehyde(UF)manufacture successfully was investigated by FTIR and DSC analysis.The results indicated that the main efficient component of active reagent was the methylolated urea,and the electrolyte had no chemical linking with urea derivatives.The active reagent reduced the surface tension of resin which improves the resin wettability onto wood.During the solidifying reaction,active reagent would reduce the activated energy of UF resin which implied that more resin molecules had attended the reaction and the bonding efficiency was improved macroscopically.The plywood and paperboard testing indicated that the synthetic technology introduced electrolyte properly could improve reaction rate and bonding strength,but reduced the tensile strengthen under the wet condition.The effect of electrolyte was discussed theoretically.It offered a good method for controlling the UF synthesis and cost during application.

Key words: urea-formaldehyde resin, electrolyte, effect mechanism