Free radical initiator delivery system
US5362698A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 8, 1993 |
| Grant date | Nov 8, 1994 |
| Priority date | — |
| Expiry date | Apr 8, 2013 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08F4/28
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
This invention relates to a process for preparing an improved polymerization free radical initiator delivery system for the polymerization of a monomer containing olefinic unsaturation which comprises uniformly dispersing a water insoluble free radical initiator, an excess amount of the polymeric product of the reaction and between about 1.0 and about 100 wt. % of a surfactant based on initiator in water to form an aqueous mixture containing between about 5 and about 40 wt. % solids; subjecting the dispersion to treatment at a temperature of between about -25.degree. C. and about 0.degree. C. under from about 50 to about 400 milli Tort vacuum for a period of from about 5 to about 24 hours to remove water and to form uniform coprecipitated initiator/polymer microparticles having an average particle diameter of between about 0.001 and about 100 microns and then diluting the coprecipitated microparticles with water under vigorous agitation to form a microparticulate dispersion of low viscosity containing from about 5 to about 40 wt. % solids which is suitable as the initiator feed for contacting said monomer in a polymerization reaction.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.