Study on Curing Behavior of Low Molar Ratio Urea-Formaldehyde Resins with Different Curing Agents
In order to characterize the curing behavior of low molar ratio urea-formaldehyde (UF) resin, the curing time and thermal analysis in curing reaction of the UF resins and the bonding strength and formaldehyde emission of plywood bonded by five kinds of low molar ratio UF resins with six different curing agents were studied. The results indicated that the UF resins with the molar ratio of formaldehyde to urea more than 1.0 could get reasonable curing time. The heat enthalpy of UF resins significantly increased with the enhancing the acidity of curing agent. The plywood manufactured by the UF resins with 1.1 molar ratio showed much higher bonding strength and lower formaldehyde emission.
Jinglong Bu, Zhengyi Jiang and Sihai Jiao
Y. H. Dong et al., "Study on Curing Behavior of Low Molar Ratio Urea-Formaldehyde Resins with Different Curing Agents", Advanced Materials Research, Vols. 150-151, pp. 965-968, 2011