FUNGAL DECAY RESISTANCE OF LOBLOLLY-PINE OR SWEETGUM REACTED WITH AQUEOUS POTASSIUM IODATE

In this study, we investigated the protection of wood based on complex ation of biocides with wood. We found that loblolly pine and sweetgum wood blocks soaked in aqueous potassium iodate for 1 day resisted deca y by brown- and white-rot fungi even after 2 weeks of water leaching. Threshold retentions of iodate for Gloeophyllum trabeum were 0.5 and 1 % by weight of iodate solution in wood for unleached and leached block s, respectively. For Coriolus versicolor, the threshold retention was 0.1% for both unleached and leached blocks. Retention of iodate in lea ched wood ranged from 21 to 73% that of unleached wood. Retentions of iodate were higher in loblolly pine than in sweetgum. Infrared spectru m of iodate-reacted wood indicated that iodate forms complexes with ce ll-wall polymers of wood, probably with cis diols of hemicelluloses an d lignin. However, the intensity of this absorption was weak. Also, a small amount of oxidation of lignin in wood was found.