Surveying the Adhesive Interaction on the Laminated Particleboard

Adhesives are used in many different applications with wood products same as particleboard (PB). In this work, the curing reaction of system consisting of some adhesive same as urea formaldehyde (UF), urea-melamine formaldehyde (MUF) and epoxy was studied in different ratios by using FTIR and non-isothermal DSC techniques. Compared to other wood adhesives, such as phenol-formaldehyde (PF) or diphenyl methane di-isocyanate, UF resin possesses some advantages such as fast curing, good performance in the panel, water solubility and lower price. From the infrared spectra using a peak-height method, which was based on the ratio of the height of the characteristic to reference absorbance peak, degree of conversion at different temperature were calculated. FTIR measurements showed decrease in the intensity of the absorption band of epoxide group at 916 cm-1 during curing process. At all temperature, the degree of conversation increased when the intensity of the band at 916 cm-1 decreased. The rate of epoxide conversion depends on the weight ratio of adhesives and also on the temperature of cure reaction. In general, the results obtained from isothermal DSC experiments showed that the rate of reaction is proportional to the heat flow. A higher isothermal temperature and higher urea formaldehyde concentration led to increase in the reaction rate.