Zur Feuchtebeständigkeit und Hydrolyseresistenz von mitteldichten Faserplatten (MDF). Tl.1: Einfluss des Aufschlussverfahrens und des Bindemittels auf die physikalisch-technologischen Eigenschaften von MDF

Medium density fibreboards (MDF) from pine wood were made using fibres generated by the conventional thermomechanical pulping (TMP) and chemo-thermomechanical pulping (CTMP). As binders alkaline curing phenolformaldehyde resin (PF-resin), tanninformaldehyde resin (TF-resin) and a binder based on polymeric diphenylmethane diisocyanate (PMDI) were used. The results reveal that boards prepared from CTMP are superior in bending strength, transverse tensile strength and transverse tensile strength after boil test (V100 value) compared to boards from TMP. However, boards prepared from CTMP are slightly higher in thickness swelling and water absorption, the degree depends on the used resin. Further, the results indicate that using the blender gluing technique leads to better physical-mechanical properties of the boards than the conventional blowline gluing technique.