Abstract: Thermoplastic branched polycarbonate resins are prepared by equilibration of linear aromatic polycarbonate with polyhydric phenol having more than two hydroxy groups in the presence of a catalyst.In another aspect of the invention, thermoplastic branched polycarbonate resins are prepared by equlibration of branched aromatic polycarbonate with polyhydric phenol having more than two hydroxy groups per molecule, preferably 1,1,1-tris-(4-hydroxyphenyl)ethane, in the presence of a carbonate equilibration catalyst, preferably tetrabutylammonium tetraphenylborate.

Abstract: Polycarbonates containing aliphatic dicarboxylic ester groups, and having glass transition temperatures and processing temperatures lower than the corresponding homopolycarbonates are prepared via an intermediate which is in turn prepared from a dihydroxyaromatic compound and a C.sub.4-6 aliphatic dicarboxylic acid anhydride, preferably succinic anhydride. Phosgenation of said intermediate produces the desired soft segment polycarbonate.

Abstract: A process which comprises reacting interfacially a dihydric phenol, a carbonate precursor and a prior prepared salt of an aliphatic alpha omega dicarboxylic acid having from 8 to about 20 carbon atoms thereby producing a copolyestercarbonate.

Abstract: Macrocyclic oligomers, including polycarbonates, polyesters, polyamides, polyimides, polyetherketones and polyethersulfones, are conveniently prepared from various spiro(bis)indane compounds, especially the 6,6'-difunctional 3,3',3'-tetramethylspiro(bis)indanes. The macrocyclic oligomers may be conveniently converted to linear polymers.

Abstract: Thermoplastic branched polycarbonate resins are prepared by equilibration of linear aromatic polycarbonate with polyhydric phenol having more than two hydroxy groups in the presence of a catalyst.

Abstract: Cyclic polycarbonate (or thiol analog) oligomer mixtures are prepared by the reaction of bishaloformates or their thio analogs, or mixtures thereof with dihydroxy or dimercapto compounds, with alkali metal hydroxides and various amines. The oligomer mixtures may be converted to polycarbonates or their thiol analogs by a method which is particularly adaptable to integration with polycarbonate processing operations. Polymerization may be conducted simultaneously with molding, extrusion and the like. The oligomer mixtures are adaptable to the preparation of filled prepregs.

Abstract: A catalyzed interfacial polycondensation aromatic polycarbonate process comprising mixing a water soluble metal salt of a dihydric phenol with an aqueous solution of a strong base and a polymerization catalyst in an inert organic solvent; heating the mixture; concurrently adding a carbonyl halide, additional strong base and additional water soluble metal salt of a dihydric phenol to the heated mixture to form the cyclic oligomeric polycarbonate; and recovering the cyclic oligomeric polycarbonate. The preferred process utilizes the di-sodium salt of bisphenol-A, triethylamine polymerization catalyst and methylene chloride solvent with phosgene to form the cyclic oligomeric polycarbonates. The cyclic oligomeric polycarbonate products are accumulated in the organic phase of the reaction mixture and recovered therefrom by conventional techniques.

Abstract: Cyclic heterocarbonates containing linkages such as ester, urethane, imide, ether sulfone, ether ketone or amide may be prepared from the corresponding bishaloformates. They may be converted to linear copolycarbonates.