Amine copper quat

The voluntary withdrawal of chromated copper arsenate (CCA) as a wood preservative for domestic applications was driven by public concerns over its health and environmental profile. In its place have risen two competing systems, the amine copper quat (ACQ) system and the copper azole system. Both systems avoid using heavy metals such as chromium and arsenic and rely on the co-biocidal effects of copper and organic biocides. The elimination of CCA has created many opportunities for oleochemicals as preservative companies try to develop formulations that are not only environmentally friendly but can also match the preservative performance of CCA [66]. The ACQ system is based on didecyldimethyl ammonium bicarbonate and has produced a significant demand for ClO-based amine and quat. The azole systems use biocides such as tebuconazole and propiconazole in combination with copper ethanolamine complexes. Ethoxylated amines [67] and amine oxides [68] have been described as providing improved performance in azole-based systems. Other copper systems have employed ethoxylated diamines [69] and amine oxides [70] to enhance performance. 

ACQ is a water-based preservative, composed of a combination of copper oxide, quat as didecyldimethylammoninm chloride, and either ammoniacal (ACQ type B) or amine (ACQ type D). ACQ does not contain arsenic or chrominm and its application also provides a clean paintable snrface. 

Hydrophobic quats such as di(hydrogenated tallow)dimethyl ammonium chloride have been claimed to provide waterproofing [71] and improvements in copper leach resistance in pressure-treated lumber [72], as have amine oxides [73]. Alkoxylated amines and diamines can also be used to improved water repellency in pressure-treated lumber [74]. 

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