Dibutyltin Compounds Research Articles

Rapid Analysis of Dibutyltin Compounds and Tricresyl Phosphate in Polyvinyl Chloride (PVC) by Thin Layer Chromatography

A simple and rapid determination method of dibutyltin compounds and tricresyl phosphate (TCP) contained in polyvinyl chloride (PVC) by thin layer chromatography (TLC) was developed. Contents of dibutyltin compounds and TCP in PVC are limited to lower than 50ppm and 1, 000ppm, respectively, by the Food Sanitation Law of Japan.Standard determination methods of these compounds involve such difficulties as timeconsuming pretreatment for gas chromatographic analysis, or indistinct spot formation on paper chromatography.Test solution for the proposed method was prepared as follows; 0.2g of PVC sample was dissolved in tetrahydrofuran (THF), and the polymer was precipitated by adding ethanol at 10 times the THE volume. The filtrate was evaporated to dryness, and the residue was taken up in 1ml of ethanol, and divided into halves. One half was used for the analysis of dibutyltin compounds, and the other for the analysis of TCP, after hydrolysis with potassium hydroxide. Detection limits of this method for dibutyltin dichloride and TCP were 50ng and 250ng, respectively.

Speciation of methyltin and butyltin compounds in eelgrass ( Zostera marina L.) leaf tissue from the great bay estuary (NH)

An analytical procedure for extraction of methyl- and butyltin compounds from eelgrass leaf tissue and their determination by a sensitive hydride generation-atomic absorption method is given. A 6 M HCl solution effectively extracts methyltin, and mono- and dibutyltin compounds, but tributyltin requires 2/1 (v/v) dichloromethane-methanol for efficient extraction. Hydride formation of all compounds by sodium borohydride in aqueous media is effective except for tributyltin which requires use of tetrabutylammonium borohydride in dichloromethane. Determinations of methyl- and butyltin compounds in eelgrass samples from the Great Bay Estuary (NH) demonstrate that, at the time of sampling (October, 1987), tributyltin pollution was minimal in this well-mixed estuarine system. Results from a mesocosm polluted with dibutyltin suggest that determination of butyltin compounds in seagrass tissue could be a sensitive means of detecting their presence in the aquatic environment, and could be used to monitor butyltin pollution.

Degradation of Tributyl Tin and Dibutyl Tin Compounds in Environmental Waters

The degradation of tri-n-butyl tin (TBT) and di-n-butyl tin (DBT) compounds in river and sea water samples was studied. In river water (Daini Neya River), TBT was degraded with time, and the concentration of inorganic tin increased. DBT was also degraded with time, and the concentrations of n-butyl tin (MBT) compounds and inorganic tin (the degradation products) increased. The half lives of TBT and DBT were about 11 days and 5 days, respectively. In seawater from Sakaisenboku Harbour (one of the most polluted areas in Osaka Bay), TBT and DBT were degraded in a manner similar to that in Daini Neya River water, but in seawater from other areas of Osaka Bay these compounds were little degraded.

Deterhination of Dibutyltin and Tributyltin Compounds in Sea Water by Graphite Furnace Atomic Absorption Spectrometry

Abstract Dibutyltin and tributyltin compounds in artificial sea water were determined at sub-ppb levels. These compounds are separated from matrix elements in aqueous solutions by a simultaneous hydride generation dichloromethane extraction. After dichloromethane is vaporized, the residue is dissolved in hexane and is directly injected into the treated graphite tube and the signal is measured by a Zeeman atomic absorption spectrometer.

Simultaneous Gas Chromatographic Determination of Dibutyltin and IHbutyltin Compounds in Biological and Sediment Samples

A method is described for the simultaneous determination of nanogram amounts of dibutyltin and tributyltin compounds in biological and sediment samples. These compounds are converted to the corresponding chlorides with HCl, extracted with ethyl acetate-hexane (3 + 2) for biological samples and with hexane for sediment samples, and hydrogenated with sodium borohydride. The corresponding hydrides, Bu2SnH2 and Bu3SnH, are detected by electron-capture gas chromatography after cleanup by silica gel column chromatography. Detection limits are 1.0-2.0 and 0.5-1.0 ng/g, respectively, for biological and sediment samples.

Bioconcentration of butyltin compounds by round crucian carp

Bioconcentration factors (BCF) by round crucian carp and partition coefficients between n‐octanol and water (Pow) were measured for dibutyltin, tributyltin and triphenyltin compounds. Pow was 0.97–3.66 for 7 organotin compounds. BCF of tributyltin and triphenyltin compounds was 1.70–2.77 for muscle, 1.70–2.66 for vertebra, 2.05–3.70 for liver and 1.49–3.50 for kidney.

Electrochemical Behavior of Dibutyltin(IV) Compounds and Their Determination at ppb Levels by Differential Pulse Anodic Stripping Voltammetry

Abstract The electrochemical behavior of dibutyltin(IV) compounds (Bu2SnX2) (X=chloride, laurate (L), and 6-methylheptyl maleate (MHM)) in 50% (v/v) and 80% (v/v) ethanol–water media (apparent pH 7.3) containing 0.002% Triton X-100 has been investigated by polarography and cyclic voltammetry. It has been found that Bu2SnX2 gives a two-electron transfer step at about −0.8 V vs. SCE, which consists of very close two one-electron steps, and a two-electron step at about −1.4 V in both media. Over the potential range of either side of the first reduction wave, both Bu2SnX2 and their reduction products are significantly adsorbed on the surface of a mercury electrode in 50% (v/v) ethanol, but not in 80% (v/v) ethanol. The adsorbed reduction products are readily re-oxidized at the mercury electrode in 50% ethanol. The re-oxidation peak was successfully utilized for the determination of traces of Bu2SnCl2 by means of the differential pulse anodic stripping voltammetry (DPASV) over the concentration range of 3–50 ppb (μg dm−3) at the deposition time of 60 s. The DPASV behavior of Bu2SnX2 (X=chloride, L, MHM, and 1-dodecanethiolate) has been investigated in a 50% ethanol medium in detail. Further, a procedure has been developed for determining Bu2SnX2 in natural water down to ppb levels.

The effects of a thermal stabilizer on the photooxidation of PVC

AbstractThe influences of heat treating of PVC on photooxidation were studied by spectroscopy. PVC containing thermal stabilizers selected from metal stearates, dibutyltin compounds and mercaptide were heat treated and then irradiated by a weatherometer at 0°C. Stabilizing action of metal stearate for photooxidation of PVC is decreased by heat treating prior to irradiation. Dibutyltin compounds show good photostability, especially, dibutyltin benzylmaleate is enhanced by heat treating. Mercaptide shows weak photostability, and stability is decreased furthermore by heat treating. Binding energy of sulphur was measured by XPS spectrometry. Divalent sulphur is oxidized to hexavalent in irradiated PVC films.

Intermolecular forces and hyperfine interactions in cyclic dibutyltin compounds

Etude des spectres Mossbauer de 119 Sn a temperature variable des composes cites a l'etat solide et dans des solutions gelees de n-butylbenzene pour clarifier les similarites de structure et les proprietes dynamiques du reseau des conformeres chiraux et de leur melange racemique

Separation of organotin compounds by using the difference in partition behaviour between hexane and methanolic buffer solution. Part 1. Determination of butyltin compounds in textiles by graphite furnace atomic-absorption spectrophotometry

A method for determining tributyltin compounds (TBTs) and dibutyltin compounds (DBTs) in textiles has been studied by graphite furnace atomic-absorption spectrophotometry. They are successfully extracted from textiles with methanol containing 0.05% of hydrogen chloride. Their partition between hexane and a methanolic buffer solution (pH 8.5) was studied by varying the methanol concentration of the aqueous buffer phase. Only TBTs can be extracted with hexane from a methanolic buffer solution consisting of 40 ml of methanol and 30 ml of buffer solution. TBTs are absorbed on an alumina column and eluted with a small volume of dichloromethane. DBTs remaining in the aqueous phase are extracted with dichloromethane as a complex with 4-(2-pyridylazo)resorcinol. After evaporation of the dichloromethane, the residue is heated with concentrated nitric acid and its tin concentration is determined by atomic-absorption spectrophotometry.

Spectres de vibration de composés organiques de la colonne IVB : III. Dérivés aminés organostanniques: Hexaalkyldistannazane, aminotributylétains N-disubstitués et bis(dialkylamino)dibutylétains. Analyse des spectres et détermination du champ de forces de valence de C 3SnN(CH 3) 2

The IR and Raman spectra of N-ethylhexabutyldistannazane [(n-C 4H 9) 3Sn] 2NC 2H 5, of six aminotributyltin compounds (n-C 4H 9) 3SnN ▪, where R and R′ are alkyl or phenyl groups, and of three bis(dialkylamino)dibutyltin compounds (n-C 4H 9) 2Sn(NR 2) 2 where R is an alkyl group, have been examined in the 3600–100 cm −1 region. Assignments were discussed for the characteristic vibrations of these derivatives. The valence force field of C 3SnN(CH 3) 2 has been computed using the results for dimethyl ether (methyl groups) and triethylchlorotin (carbon bound to tin). Experimental and calculated frequencies are in good agreement.

Tests of dibutyltin compounds as potato blight fungicides

SUMMARYDibutyltin dicarboxylates were about one‐tenth as effective as fentin acetate in controlling potato haulm blight (Phytophthora infestans) in laboratory tests on detached leaflets, but were less phytotoxic. Tributyltin acetate was no more effective than dibutyltin diacetate; dioctyltin dichloride was ineffective.

Polarography of Dibutyl Tin Dichloride and Its Application to the Determination of Stabilizers Eluted from Polyvinyl Chloride Films

Dibutyl tin compounds are widely used as the stabilizer of polyvinyl chloride. The determination of such dibutyl tin compounds used can be successfully carried out by square wave polarography using mercuric pool as the electrode. Various kinds of polyvinyl chloride films were manufactured by use of dibutyl tin compounds (chloride, maleate and laurate) as the stabilizer, then the amount of stabilizer eluted by 0.01N hydrochloric acid, 4v/v% acetic acid or 20v/v% ethanol was measured by polarography. From the results it became clear that the organic tin in the stabilizer is more apt to be eluted by ethanol than that in dibutyl tin maleate. The stabilizer was scarcely eluted from rigid polyvinyl chloride in the experimental conditions.