Amine Oxides for Use in Wood Protection: III. Penetration Aids for Wood
This paper highlights the advantages of using amine oxides as penetration aids for quaternary ammonium compounds (quats) and azoles in the area of wood protection. It was found that the use of amine oxide effectively enhanced the penetration and distribution of quats and azoles. For both southern yellow pine (SYP) and Douglas fir wood samples, the addition of cocodimethylamine oxide (Barlox® 12) in didecyldimethylammonium bicarbonate/carbonate (Carboquat® 250T) significantly improved the penetration of Carboquat® 250T. SYP and Douglas fir wood blocks treated with Barlox® 12 and Carboquat® 250T exhibited 60% and 57% increase respectively in quat retention in the center cross section wafer compared to samples treated with Carboquat® 250T alone. The blend of Barlox® 12 and propiconazole treatment showed roughly a 37% and 33% improvement in azole retention in the middle cross section piece of SYP and Douglas fir wood blocks. Using amine oxide, the retention of quat and azole in the inner zone was comparable to the retention of quat and azole in the outer zone in the absence of amine oxide. The color indicator spray test and chemical analysis
illustrated an even distribution of the active preservatives of quat and azole in wood with the aid of amine oxide. It was further confirmed by chemical analysis that amine oxide can carry quats and azoles into wood to the same depth as amine oxide travels into the wood. Therefore, it is suggested that amine oxide measurement can be used as a surrogate agent to determine the presence of azoles in the treated wood.
Keywords: amine oxides, quats, azoles, penetration, distribution