| 摘要 |
The invention comprises compounds of formula (R1)2Sn(OOC.HC=CHCOOR2)2, where R1 and R2 represent alkyl radicals, the said compounds being prepared by reacting a dialkyl tin oxide with a mono-alkyl ester of maleic acid. Air may be blown through the reaction mixture. The compounds of the invention may be used to stabilize polyvinyl chloride and other polychloro compounds against deterioration by heat and light (see Group IV (a). In an example maleic anhydride is dissolved in n-butanol and dibutyl tin oxide added to the ester so-formed. Other compounds specified include dibutyl tin di-(mono-ethyl-, di-(mono-isopropyl- and di-(monoamyl-maleate)s. Specifications 664,133 and 711,145 and German Specification 867,913 are referred to.ALSO:Polyvinylchloride compositions containing dioctyl phthalate are stabilized against deterioration by light and heat by addition of 1-2 per cent of a dialkyltin di(mono-alkyl maleate) of formula (R1)2Sn(OOCCH = CHCOOR2)2, where R1 and R2 are alkyl groups. Compounds specified are dibutyltin di (monoethyl maleate), dibutyl tin di(monoisopropyl maleate), dibutyl tin di(monobutyl maleate) and dibutyl tin di(monoamyl maleate). |
