Process for preparing vinyl chloride paste resin
US6765073B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 5, 2001 |
| Grant date | Jul 20, 2004 |
| Priority date | — |
| Expiry date | Dec 31, 2021 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08F14/06
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
A process for preparing a vinyl chloride paste resin comprising the steps of homogenizing a vinyl chloride monomer in an aqueous medium together with an oil-soluble polymerization initiator to form a first aqueous dispersion, and subjecting the first dispersion to a micro-suspension polymerization wherein a second aqueous dispersion containing a vinyl chloride monomer and a surface active agent is added to the reaction system in such a manner that the addition is started after starting the polymerization but by the time the polymerization conversion of the initially charged monomer reaches 30%, and is terminated by the time the polymerization conversion of the initially charged monomer reaches 95%. The process has an improved productivity since the heat removing area of a jacket of a reactor is prevented from lowering during the polymerization to increase the amount of heat removed and since the polymer yield per unit volume of the reactor is increased.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.