Process for manufacture of a solution of dialkyl peroxydicarbonate
US6258906A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Apr 23, 1999 |
| Grant date | Jul 10, 2001 |
| Priority date | — |
| Expiry date | Apr 23, 2019 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07C407/003
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
The dialkyl peroxydicarbonates with short alkyl chains, are used for the aqueous suspension polymerization of vinyl chloride, in the form of a solution in a dialkyl alkanedicarboxylate. The preferred solvents are hexanedicarboxylates (adipates) derived from adipic acid and C.sub.6 -C.sub.10 alkanols. The peroxydicarbonate concentration of the said solutions is generally 15-40% by weight. The process according to the invention produces vinyl chloride polymers of improved quality resulting in shaped articles exhibiting markedly fewer fisheyes. The invention also relates to a two-stage process for the manufacture of a solution of dialkyl peroxydicarbonates with short alkyl chains which is particularly suited for the aqueous suspension polymerization of vinyl chloride. According to this process an inorganic salt is used in the stage of manufacture of the peroxydicarbonate (first stage) and the latter is subsequently isolated by extraction by means of a water-insoluble solvent (second stage).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.