Tributyltin naphthenate

TBTL is a microbicide of minor importance in the field of material protection its antimicrobial activity corresponds to that of tributyltin naphthenate (19.6.4.). 

There is a listing of dermal LDso values in animals for a number of organotin compounds (Smith 1978). A dermal LDso in rabbits was reported to be 11,700 mg/kg bis(tributyltin)oxide (Elsea and Paynter 1958). For rats, an LDso of 605 mg/kg is given (Smith 1978). Despite variations in values for other compounds such as benzoates, naphthenates, and fluorides, the acute dermal toxicity of organotin compounds is generally less than by the oral route. The LDso values for representative species in the acute- and intermediate-duration category are recorded in Table 2-4. Doses are expressed as mg/kg/day compound rather than as doses of tin. 

Tributyltm species, especially (Bu3Sn)20 and tributyltin phosphate and naphthenate, have been used in wood preservation as fungicides and as biocides for destructive insects. Tributyltins (and to a lesser extent, triphenyltins) have been used in marine antifoulant paints due to their broad range activity. The use of organotin polymers in which the... 

Wood is attacked by insects, fungi, and bacteria. Tributyltin compounds are powerful fungicides and bactericides, and tributyltin oxide or naphthenate has been used for wood preservation since the early 1960s. The wood is often impregnated with the organotin compound in an organic solvent by a double-vacuum process. A sealed chamber containing die wood is evacuated to low pressure. The chamber is flooded with the preservative and the vacuum is released so that the preservative is forced into the wood, then the vacuum is restored to remove the excess solution. 

However, fungi can be prevented from attacking the wood by treating it chemically and keeping its moisture content to a minimum. Chemical treatment may be solvent-borne or water-borne. Active ingredients include pentachlorophenol, tributyltin oxide and copper and zinc naphthenates (solvent-borne) and mixtures of copper sulphate, sodium or potassium dichromate, and hydrated arsenic pentoxide (water-borne). These act in a variety of ways to destroy or inhibit the growth of fungi. 

Derivatives of both two- and four-valent tin have found use as catalysts in urethane foams. In addition to the more commonly used dibutyltin (IV) dilaurate, dibutyltin (IV) diacetate, dialkyltin (IV) oxide or salts of two-valent tin with a variety of carboxylic acids such as stannous octoate, hexoate and naphthenate, there are also available chlorine-containing compounds (dibutyltin dichloride, SnCl2, SnClJ, sulphur-containing compounds (e.g. tributyltin laurylmercaptate), and complexes such as stannous quinolinolate or dibutyltin bis(acetylacetonate). Other catalysts... 

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