Effects of Chemical Mixtures of Phosphorus and Boric Types on Heat Release Performance of Wood

Abstract

Four phosphorus type chemicals were mixed with disodium octaborate tetrahydrate in various mixing ratios. These mixed chemicals were impregnated into Sugi wood, and the treated woods were evaluated for heat release performance by cone calorimeter tests. Total heat release of woods treated with mixed chemicals at ratios of 9 : 1 and 8 : 2 for diammonium hydrogenphosphate and poly-phosphat-ic carbamate, and treated with guanidine phosphate at mixing ratio at 9 : 1 was less than that of woods treated with mixtures using phosphorus type chemicals. However, woods treated with mixtures using ammonium dihydrogenphosphate did not result in the mixing ratios that decrease total heat release. According to the observations of combustion behavior during heating, it was concluded that decreases of total heat release for wood treated with mixed chemicals were related to suppression of glowing of wood. The woods treated with mixed chemicals at mixing ratios that decreased the total heat release as cited above, also showed decreased total mass loss or effective heat of combustion than the woods treated with phosphorus type chemicals used in the mixture. According to these data, it was concluded that mixed chemicals that decreased total heat release of wood, caused this by a synergistic effect between the phosphorus and the boric type chemicals. (cid:9487)(cid:9513)(cid:9533)(cid:9531)(cid:9523)(cid:9526)(cid:9512)(cid:9527)