MANUFACTURE OF SPIROBIINDANE POLYCARBONATE, PRODUCTS THEREBY AND PRODUCTS THEREFROM

• Main Authors: JIERII CHIYAARUZU RINCHI, GARII REI FUARAA
• Format: Patent
• Language: English
• Published: 22.12.1988
• Subjects: CHEMISTRY; COMPOSITIONS BASED THEREON; INFORMATION STORAGE; INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORDCARRIER AND TRANSDUCER; MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONSONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS; METALLURGY; OPTICAL ELEMENTS, SYSTEMS, OR APPARATUS; OPTICS; ORGANIC MACROMOLECULAR COMPOUNDS; PHYSICS; THEIR PREPARATION OR CHEMICAL WORKING-UP

Homo- and copolycarbonates of spirobiindane bisphenols are prepared by first reacting phosgene with a substantially pure spirobiindane bisphenol in the presence of aqueous base in a heterogeneous medium at a pH in the range of about 9-11, and subsequently adding an interfacial polycarbonate formation catalyst and, optionally, a dihydroxyaromatic compound and a chain termination agent and continuing phosgene passage at a pH of at least about 10. By this method, there may be prepared homo- and copolycarbonates of 6,6'-dihydroxy-3,3,3',3'-tetramethyl-1,1-spiro(bis)indane having high molecular weight. Said homopolycarbonates and copolycarbonates with bisphenol A may be used for manufacture of optical disks having low birefringence.