Spray drying process
Abstract
Abstract POLY (AROMATIC KETONES) AND POLY (AROMATIC SULFONES) PREPARED BY BORON TRIFLUORIDE-CATALYZED FRIEDEL-CRAFTS CONDENSATION IN HYDROGEN FLUORIDE ARE RECOVERED FROM POLYMERIZATION MEDIA BY SPRAY DRYING HYDROGEN FLUORIDE SOLUTIONS OF THE SAME WHICH CONTAIN SUBSTANTIAL PROPORTIONS OF LIQUID SULFUR DIOXIDE, PREFERABLY FROM ABOUT 90 TO 99% VOLUME. AT LEAST A PORTION OF THE SO2 MAY BE PRESENT DURING POLYMERIZATION, E.G., 50% BY VOLUME. PRODUCT SPRAY DRIED WITH SO2 IS LIGHTER IN COLOR AND CONTAINS LESS FLUORINE THAN THAT ARISING FROM SPRAY DRYING WITH HF ALONE, AND ENJOYS SUPERIOR HEAT STABILITY IN THE MELT AS COMPARED TO PRODUCT RECOVERED BY PRECIPITATION IN A NON-SOLVENT. THE POLYMER MAY BE EMPLOYED, E.G., IN ELECTRICAL INSULATION.
Inventors
- 👤 K Dahl
Bibliographic Details
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