Patent GB-866484-A (GB)
Title: Organotin compounds
IPC: C08K5/58
Filed: 1959-09-14
Abstract: Halogen containing synthetic resin compositions, particularly polyvinyl halide compositions, are stabilized against deterioration by light and heat by the addition of a condensation product of an organotin oxide, hydroxide, halide or a hydrocarbon-substituted stannoic acid with a dimercaptoacid ester of an organic diol of formula:-Rx Sn(S-A-OOC-B-COO-A-SH)4-x wherein x is 1, 2 or 3, R is a univalent hydrocarbon radical (especially alkyl, aryl, alkaryl or aralkyl), A and B are each divalent hydrocarbon radicals respectively containing up to 20 carbon atoms, the sum of the carbon atoms in A-B being not more than 25.  Plasticizers may also be present in the compositions.  Typical stabilizers specified include dibutyltin- -bis-S, S1-(1, 4-butyleneglycol dimercaptoacetate), -bis-S, S1-(1, 5-pentanediol dimercaptoacetate), -bis-S, S1-(1, 8-octanediol dimercaptoacetate), and -bis-S, S1-(1-ethyl-1, 3-hexane diol dimercaptoacetate : trioctyltin-diethylene glycol di-5-mercaptovalerate: triphenyltin and tri-benzyltin-S-ethylene glycol dimercapto acetate and butyltin tris-S, S1, S11 (propylene glycol di-b -mercapto butyrate).ALSO:The invention comprises organotin compounds of formula:  RxSn(S-A-OOC-B-COO-A-SH)4-x wherein x is 1, 2 or 3, R is a univalent hydrocarbon radical (e.g. alkyl, aryl, alkaryl, aralkyl) containing up to 10 carbon atoms, A and B are each divalent hydrocarbon radicals respectively containing up to 20 carbon atoms, the sum of the carbon atoms in A and B not exceeding 25.  They may be prepared by condensing an organotin oxide, hydroxide, halide or hydrocarbon substituted stannoic acid with the dimercaptoacid ester, in the presence if necessary of a halogen acceptor such as an alkaline hydroxide, alkali metal carbonate, ammonia or an amine.  R in the formula above may be butyl, octyl or phenyl.  Preferred diols include ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, dipropylene glycol, 2-ethyl-2-butyl-1,3-propanediol, 2,2-diethyl-1,3-propanediol, 2-ethyl-1,3-hexanediol, hexylene glycol, 1,5-pentanediol, 12-hydroxystearyl alcohol, 1,10 dodecanediol.  Specified mercapto acid which may be esterified include mercapto acetic acid, b -mercaptopropionic acid, thiosalicylic acid, a -mercaptopropionic acid, mercaptobutyric acid, mercaptovaleric acid, a -mercaptostearic acid, a -mercaptocaprylic, a -mercaptopelargonic acid, a -mercaptolauric acid, a -mercaptopalmitic acid, a -mercaptophenylacetic acid, a -mercaptodiphenylacetic acid, a -mercaptodiethylacetic acid, 5-mercaptovaleric acid, 6-mercaptocaproic acid, 8-mercaptocaprylic acid and 12-mercaptolouric acid.  The reaction may take place at temperatures between room temperature and 50 DEG C. (the water produced being removed by additional heating) under an inert atmosphere and in the presence of an inert solvent such as benzene, toluene or methyl alcohol.  The preparation of the following compounds is described: dibutyl tin bis-S,S1-(ethylene glycol dimercapto acetate), tributyl tin S-diethylene glycol di-5-mercaptovalerate, trioctyl tin-S-diethylene glycol di-5-mercaptovalerate, triphenyl tin and tribenzyl tin-S-ethylene glycol-dimercaptoacetate, dibutyltin and dioctyl tin bis(1,4-butylone glycol dimercaptoacetate), dibutyl tin-bis-1,5 pentanediol dimercaptoaceaate)-bis(1,8-octanediol dimercaptoacetate), and -bis-(1-ethyl-1,3-hexanediol dimercaptoacetate, di-ethylhexyltin bis-(ethylone glycoldimercaptoacetate) and butyl tin-bisS,S1,S11(propylene glycol di-b -mercaptobutyrate). The compounds of the invention may be used in halogen-containing synthetic resin compositions as stabilisers against deterioration by light and heat.  Dimercapto acid esters of organic diols. Mercaptoacetic acid is reacted with ethylene glycol in toluene solution using p-toluene sulphonic acid as esterification catalyst. Reference is also made to the preparation of ethylene glycol-di-12-mercapto stearate and -di-5-mercapto valerate from ethylene glycol and 12 mercaptostearic acid and 5-mercaptovaleric acid respectively: propylene glycol dib -mercaptobutyrate from propylene glycol and b -mercaptobutyric acid: 2-ethyl-2-butyl-1,3-propanediol di-thiosalicylate from 2-ethyl-2-butyl-1,3-propanediol and thiosalicylic acid: and 12-hydroxystearyl alcohol dimercaptoacetate from 12-hydroxystearyl alcohol and mercaptoacetic acid.