Antimony, compounds

Antimony [7440-36-0] is the fourth member of the nitrogen family and has a valence shell configuration of The utilisation of these orbitals and, in 

Includes estimates for countries having centrally planned economies in 1988. Includes estimates for China. 

A recommended exposure limit for antimony compounds of 0.5 mg /m (as Sb) has been given (2). Disposal may be effected by washing residues down the drain at very high dilution unless prohibited by local regulations. 

Kirk-Othmer Encyclopedia of Chemical Technology (4th Edition) 

Stibiae may be prepared by the treatment of metal antimonides with acid, chemical reduction of antimony compounds, and the electrolysis of acid or alkaline solutions usiag a metallic antimony cathode  

Antimony [7440-36-0] is the fourth member of the nitrogen family and has a valence shell configuration of Ss 5p[ The utilization of these orbitals and, in some cases, of one or two 5 6 orbitals permits the existence of compounds in which the antimony atom forms three, four, five, or six covalent bonds. 

The H-nmr spectrum of stibabenzene (1) has been reported and it shows the characteristic signal pattern of the Group VB heteroaromatics, the a-protons giving a doublet at extremely low field, while the 3 and signals are in 

Stibabenzene (1) on treatment with methyllithium yields anion (2), which on quenching affords a mixture of 1,2-dihydro--1-methyl- (3) and 1,4-dihydro-1-methyl- (4) -stibabenzene. 

The anion (2) may be obtained from 1,4-dihydro-1-methyl--stibabenzene (4), prepared by the reaction between methyl-lithium and 1-chloro-1,4-dihydrostibabenzene. H- and C-nmr spectral data have been recorded (Ashe and T.W. Smith, Tetrahedron Letters, 1977, 407). 

1-Dibutyl-1,4-dihydrostannaphenyllithium (5) on quenching with methyl iodide gives 1,1-dibutyl-1,4-dihydro-4--methylstannabenzene (6), which on treatment with antimony trichloride followed by 1,8-diazabicyclo[5.4.0]undec-7-ene yields 4-methylstibabenzene (7). 

4-tert-Butylstibabenzene (8) may be obtained by a similar route. The 4-methyl- and 4-tert-butyl- derivatives are easily distillable liquids and at 25° the former shows no change after,1h, but after 24h it has polymerised. Pure stibabenzene (1) polymerises rapidly at 25°. Alkyl derivatives (7) and (8) do not form any detectable quantities of a Diel-Alder dimer af bismabenzene p. 57), although (7) gives the expected Diels-Alder adduct with dimethyl acetylene-dicarboxylate (Ashe, T.R. Diephouse, and M.Y. El-Sheikh, 

The EU has been conducting a risk assessment on this category 3 carcinogen (at present the risk of carcinogenicity is considered relatively small) but the process is still incomplete. Suppliers have taken steps to reduce exposure by developing non-dusting and palletised grades. 

The same company also sells Pyrobloc grades of anhydrous sodium antimonate as synergists for saturated polyesters, and for translucent and brightly coloured products, together with Timonox , TMS , and Trutint antimony oxide flame retardants. 

Fireshield and Thermoguard antimony oxide-based products have been developed by Laurel Industries. 

Ashland sells an epoxy vinyl ester thermosetting polymer with antimony trioxide already mixed in, called Hetron FR992Sb. (The manufacturing methods used with vinyl ester polymers involve very little mechanisation, and the handhng of powdered antimony trioxide would introduce significant additional costs.) 

Chinese researchers have tried combining dibromodiphenyl ether flame retardant with antimony trioxide and a nanoclay to make flame retardant polyamides. Better results were obtained than with similar samples without nanoclay. In particular the researchers achieved a very low peak heat release rate, and a V-0 rating in the UL-94 test. Carbon nanotubes are expected to show some benefit in FR terms. Nanoclays appear to stop PU from dripping, but their effectiveness is lost if the quaternary ammonimn compoimd used to treat the clay decomposes in the heat of a fire. 

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As can be expected, antimony compounds resemble those of arsenic. In the Marsh test, antimony compounds again give a black deposit which, unlike that formed by arsenic compounds, is insoluble in sodium chloratefi) solution. 

Perchloric acid Acetic acid, acetic anhydride, alcohols, antimony compounds, azo pigments, bismuth and its alloys, methanol, carbonaceous materials, carbon tetrachloride, cellulose, dehydrating agents, diethyl ether, glycols and glycolethers, HCl, HI, hypophosphites, ketones, nitric acid, pyridine, steel, sulfoxides, sulfuric acid... 

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