Dimensional Stability Properties of Medium-Density Fiberboards Produced Using Silicone-Based Chemicals

center dot The purpose of this study was to investigate the effects of two different silicon -based water-repellent chemicals (Dow Corning 87 and Xiameter PMX-200 1000cs) added to melamine urea formaldehyde glue (1.07 mol, 5 % melamine additive) in different proportions (0.5 %, 1.0 %, 1.5 % and 3.0 %) on the dimensional properties (swelling -shrinkage and length extension and shrinkage) of the medium density fiberboard. In the context of the study, the dimensional stability properties of the boards were measured based on the TS EN 318:2005 standard. It was observed that, when the relative humidity of the air conditioning room increased from 65 % to 85 %, the swelling decreased and the extension increased, respectively, in the thickness and length directions of the boards produced with silicon -based chemicals (compared to the control board produced without using silicone -based chemicals). On the other hand, it was determined that the shrinkage in the thickness and length direction of the boards decreased when the relative humidity of the air-conditioning room was reduced from 65 % to 30 %. Moreover, the dimensional stability properties of medium density boards produced with silicon -based chemicals increased (resistance to moisture).