Carboxylate-containing alkyltin heat stabilizer
A stabilizer composition, suitable for use in polyvinyl chloride compositions, can be formed by reacting a mixture of monoalkyltin trichloride, such as butyltin trichloride, and dialkyltin dichloride, such as dibutyltin dichloride, with at least one carboxylic acid, such as 2-ethylhexanoic acid, and 2-mercaptoethanol, in the presence of base, followed by reaction of the resulting product with a sulfide reagent, such as sodium sulfide. The final composition comprises a complex mixture of alkyl tin carboxylates and/or mercaptides, and of monoalkyltin sulfides and dialkyltin sulfides.
1. A composition of matter, which is useful as a heat stabilizer for polyvinyl chloride compositions, which is obtained by reacting a portion of a mixture of monoalkyltin trichloride and dialkyltin dichloride with at lease one carboxylic acid and 2-mercaptoethanol, in the presence of base, followed by reaction of the remaining portion with a sulfide reagent.
2. A composition as claimed in claim 1 wherein the alkyl moieties are all butyl.
3. A composition as claimed in claim 1 wherein the carboxylate moieties are all 2-ethylhexanoate.
4. A composition as claimed in claim 1 wherein the alkyl moieties are all butyl and the carboxylate moieties are all 2-ethylhexanoate.
5. A composition as claimed in claim 1 wherein the carboxylate moieties are all oleate.
6. A composition as claimed in claim 1 wherein the alkyl moieties are all butyl and the carboxylate moieties are all oleate.
7. A process for forming a stabilizer composition, suitable for use in polyvinyl chloride compositions, which comprises reacting a portion of a mixture of monoalkyltin trichloride and dialkyltin dichloride with at least one carboxylic acid and 2-mercaptoethanol, in the presence of base, followed by reaction of the remaining portion with a sulfide reagent.
8. A process as claimed in claim 7 wherein the monoalkyltin trichloride is of the formula RSnCl 3 with R being butyl.
9. A process as claimed in claim 7 wherein the dialkyltin dichloride is of the formula R 2 SnCl 2 with R being butyl.
10. A process as claimed in claim 7 wherein the sulfide reagent is sodium sulfide.
11. A process as claimed in claim 7 wherein the carboxylic acid is of the formula RCO 2 H with R being alkenyl of from about twelve to about twenty carbon atoms in length or alkyl of from about eight to about twelve carbon atoms in length.
12. A process as claimed in claim 11 wherein the carboxylic acid is 2-ethylhexanoic acid.
13. A process as claimed in claim 7 wherein the monoalkyl trichloride is butyltin trichloride, the dialkyltin dichloride is dibutyltin dichloride, the carboxylic acid is 2-ethylhexanoic acid, and the sulfide reagent is sodium sulfide.