| 초록 |
Formaldehyde emission of urea-formaldehyde (UF) resin adhesives for wood-based composite panels has that has been recognized as one of the major obstacles. This study investigated on microstructure of cured UF resin adhesives as a cause of formaldehyde emission. The microstructure of cured UF resin adhesives were observed using X-ray diffraction (XRD), field-emission-scanning electron microscopy, energy dispersive X-ray analysis (EDXA) or atomic force microscopy (AFM). UF resins with lower formaldehyde/urea (F/U) mole ratios showed a partially crystalline structure and spherical particles. For the first time, the EDXA result revealed three different types of chloride in cured UF resin. The observation of cured UF resins using AFM also showed a nodular structure, and etching treatment with dilute hydrochloric acid to cured UF resin also showed hard and soft phases. These results partially explain crystalline structure of cured UF resin with lower F/U mole ratio |
