Stannous octanoate

Sta.nnous2-Ethylhexa.noa.te, Stannous 2-ethyIhexanoate, Sn(CgH 302)2 (sometimes referred to as stannous octanoate, mol wt 405.1, sp gr 1.26), is a clear, very light yellow, and somewhat viscous Hquid that is soluble in most organic solvents and in siHcone oils (166). It is prepared by the reaction of stannous chloride or oxide with 2-ethylhexanoic acid. 

Stannous Octanoate Stannous 2-Ethjlhexanoate), Technical Data Sheet 176, M T Chemicals, Inc., Rahway, N.J., Dec. 1981. 

In the presence of the organic siHcate, the heavy-metal salts trigger the chain extension and cross-linking reactions that lead to siHcone mbber and volatile ethanol as a byproduct. Useful metal soaps iaclude stannous octanoate [1912-83-0], ziac octanoate [557-09-5], dibutyltin dilaurate [77-58-7], and dibutyltin diacetate [1067-33-0]. The reactivity of the different salts varies considerably. Stannous octanoate effects a cure ia 0.5—2 min ziac octanoate may require 24—96 h the dibutyltin dilaurate, 10—20 min. Heat and moisture accelerate the curing rate, but to a lesser degree than ia the case of the polysulfide mbbers. 

The high temperatures reached in the GS/MW process have been used to achieve the thermal decomposition of O-alkylcarbamates (Scheme 7.6) [15, 16]. The latter are prepared from corresponding alcohols and phenyl isocyanate in the presence of stannous octanoate [49]. 

Stannous fluoride, 24 801, 804, 8 340 Stannous fluoroborate, 24 807 Stannous octanoate, 24 826 Stannous oxalate, 24 827 Stannous oxide, 24 804—805 Stannous oxide hydrate, 24 805 Stannous pyrophosphate, 24 807 Stannous sulfate, 24 806-807 Stannylquinones, 21 254 Stanton number (St), 15 687t Stanylenka 460 HRST, 19 764 Staphylococci, coagulase-negative, 21 216 Staphylococcus aureus... 

The conventional synthesis of aliphatic polyesters based on adipic acid and a range of diols, such as 1,4-butanediol or 1,6-hexanediol, involves a high-temperature esterification reaction typically at 240-260 °C and an organometallic catalyst such as stannous octano-ate. The use of enzyme catalysis results in a much lower reaction temperature, but also the possibility of removing the esterification catalyst, giving the polyester significantly improved hydrolysis resistance. 

Another class of functional siloxane polymer that has received some attention are the fluorosiloxane materials, especially 3,3,3-trifluoropropylmethylsiloxanes. The use of conventional equilibration catalysts to produce these materials gives products which favour the cyclosiloxane in the bulk. Clarson and coworkers41 report the use of specific condensation catalysts such as stannous octanoate, potassium carbonate and barium hydroxide to prepare hydroxy terminated fluorosilicone polymers. 

Stannous octanoate has also been studied as a catalyst for the synthesis of polydimethyl-and poly(methylphenyl)siloxanes via polycondensation. 

The reaction vessel containing the Step 1 product was transferred to a dry box and treated with dl-lactide (25.2 g), glycohde (7.25 g), and 0.2 ml of stannous octanoate solution in toluene. The polymerization reaction was performed at 160°C for 8 hours and then quenched in liquid nitrogen. The polymer was isolated, dissolved in acetone, and precipitated in cold water, with the product isolated having aM of 3790 daltons and Mw of 7040 daltons. 

The most common catalysts are dibutyltin dioctanoate, dibutyltin dilaurate, or stannous octanoate at 0.1-1.0% concentration, and the distannoxanes (XR2Sn)20 are particularly effective.11 When foams are being formed, the blowing can be carried out by C02 which is released by the hydrolysis reaction (equation 23-7). 

Varying the feed ratio of the comonomers allowed regulation of the copolymer composition. The isolated yield and M of poly(PDL-co-43 mol % TMC) formed after 24 h (feed 2 1 PDL TMC) was 90% and 30900g/mol, respectively. Thus far, an alternative chemical route to random poly(PDL-co-TMC) is not known. For example, PDL/TMC copolymerizations with chemical catalyst such as stannous octanoate, methylaluminoxane, and aluminum triisoproxide resulted either in homo-poly(TMC) or block copolymers of poly(TMC-co-PDL) [114]. Chemical... 

A 0.2 M solution of stannous octanoate in toluene was used to provide a mole ratio of 60,000 for monomer/ catalyst 1,3- propane diol was used as the initiator. 

The second step entailed the preparation of a more hydrophilic copolymer, P2 (80/20 PEG/copolyester, by mole) following the same reaction scheme as that described above for PI. However, the polymerization charge consisted of PEG (120g), TMC (26.6 g, 0.888 mol), glycolide (3.34 g, 0.029 mol), and stannous octanoate (0.203 mmol as a 0.2 M solution in dry toluene). 

A major use of polyurethanes is in the manufacture of foams, both rigid and flexible. The chain-extension reactions described previously are normally used when elastomeric-type products are required, but for foams, the chain-extender molecule can be omitted and polyols with an average functionality in excess of three are used. The reaction is base-catalyzed by tertiary amines or oigano tin compounds (e.g., stannous octanoate) and must also include a blowing agent in the reaction mixture. This can be achieved by adding controlled quantities of water to the system and making use of the reaction ... 

Helder, J., Kohn, F.E., Sato, S., vanderBerg, J.W., and Feijen, J., Copol5miers of glicine and lactic obtained by stannous octanoate, Makromol. Chem. Rapid Comm, 6, 9 (1985). 

Similarly, the biodegradable polyesters polyglycolic acid and poly(f-caprolactone), also used for implantable devices (degradation even slower than that of PLA), drug delivery, and suture materials, are prepared by CROP using stannous octanoate and other catalysts as cationic initiators [8]. 

Poly(s-caprolactone) (PGL), another ester containing polymer, can be similarly synthesized by ring-opening polymerization of s-caprolactone using catalysts such as stannous octanoate. PGL itself is a semicrystalline polymer with a higher glass transition temperature between 59 °G and 64 PGL is also FDA... 

Among the initiators, tin (II) bis-2-ethylhexanoic acid (stannous octano-ate) has been the most used for preparing biomedical and pharmaceutical polymers because of its low toxicity. 

Stannous 2-ethylhexanoate sta-nos e-thol-. hek-s9- no-at (stannous octanoate) n. A polymerization catalyst for urethane foam. 

Stannous chloride (SnCy is an important component in various plating processes it is also used in nuclear medicine for the reduction of TCO4. Other tin(II) salts, such as fluoroborate, are used in the electronic industry. Tin fluoride (Snp2) is used as an effective agent against tooth decay and many clinical trials since 1955 have shown better results against both dental caries and dental plaque than those obtained with other fluoride formulations [3]. Stannous octanoate is an important catalyst in the continuous production of flexible polyurethane foam [1]. 

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