Process for continuous recovery of solid polycarbonate from solutions thereof in organic solvents
US4212967A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 22, 1979 |
| Grant date | Jul 15, 1980 |
| Priority date | — |
| Expiry date | Feb 22, 1999 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08J2369/00
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
Solid polycarbonate is recovered continuously from solutions thereof in organic solvents by a process consisting of: PA1 (a) subdividing the polycarbonate solution by steam (water vapor) at either sonic or ultra-sonic speed by means of a De Laval type nozzle; PA1 (b) conveying the dispersion thus obtained into a tubular heat exchanger having an increasing cross-section, preferably spirally-shaped or with elbow stretches having a thermal exchange coefficient of 500-1500 Kcal/h.m.sup.2 .degree.C., in which the heat dispersion is kept at 100.degree.-140.degree. C. for periods of time comprised between 0.05 and 5 seconds; PA1 (c) separating the solid from the vapors in a cyclone; PA1 (d) drying of the solid in a water vapor fluid bed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.