Combustion properties of medium-density fiberboards coated by a mixture of calcite and various fire retardants

In this study, we investigated the effect of fire retardants (FRs) on the combustion performance of medium-density fiber boards (MDFs) that were coated with mixtures of water, binder, calcite, and various FRs (FR coatings). We used MDF panels, calcite as the coating pigment, melamine formaldehyde as the binder, and FRs, including borax (BX), boric acid (BA), and zinc borate (ZB), to investigate the effects on the properties of the test boards. According to the results of combustion properties of coated MDFs with FR coatings, BA presented the highest stability, followed by BX and ZB, respectively. It was also found that the fire resistance of coated MDFs was better than that of uncoated MDF panels. For samples coated with FR coatings, the lowest burning temperature of 3% BA coatings was about 216 °C, and the highest burning temperature of 1% BX coatings was found as approximately 271 °C. The lowest mass losses were 35.5% for BA and 36% for BX. As a result, both surfaces of MDF panel can be coated with a mixture of calcite and FR, thereby improving the combustion properties of the MDFs. BA coatings showed to be have better thermal properties than both BX and ZB coatings.