Dimensional stability and creep behavior of heat-treated exterior medium density fiberboard
| Authors: | Nadir Ayrilmis, Theodore Laufenberg, Jerrold Winandy |
| Year: | 2009 |
| Type: | Miscellaneous Publication |
| Station: | Forest Products Laboratory |
| DOI: | https://doi.org/10.1007/s00107-009-0311-7 |
| Source: | European journal of wood and wood products. Vol. 67 (2009): pages 287-295. |
Abstract
A series of commercial phenol-formaldehyde bonded MDF panels were exposed to a post-manufacture heat-treatment at various temperatures and durations using a hot press and just enough pressure to ensure firm contact between the panel and the press platens. Physical properties and static flexural strengths of the post heat-treated MDF panels were evaluated according to ASTM D 1037 (2002). The results indicated that the post-manufacture heat-treatment of the exterior MDF panels resulted in improvement of thickness swelling. Water absorption and linear expansion properties were adversely affected by the heat-treatment. Modulus of rupture and modulus of elasticity values of the heat-treated panels decreased with increasing treatment temperature. A series of three 12-week creep tests were performed in climatic chambers conditioned at 65% RH, 90% RH, and cyclic 65–90% RH, all at a steady temperature of 20 ◦C. The creep tests generally followed procedures as specified in ASTM D 6815-02a (2002). Creep deflections of the panels increased with increasing temperature of the post heat-treatment.