Abstract: A multilayer product characterized by its improved weatherability and mechanical properties is disclosed. The product contains a layer A containing a member selected from the group consisting of transparent thermoplastic material and a lacquer, the member containing at least one UV absorber, a layer B containing a transparent thermoplastic material and containing at least one colorant, and a layer C containing a transparent thermoplastic material. Also disclosed is a process for the preparation of the inventive multilayer product.

Abstract: An optical data storage comprising a thermoplastic copolycarbonate is disclosed. The copolycarbonate contains at least one unit derived from dihydroxydiphenyl ether and at least one unit derived from at least one member selected from the group consisting of 4,4?dihydroxybiphenyl and 1,1-bis-(4-hydroxyphenyl)-3,3,5-trimethylcyclohexane.

Abstract: A multi stage process for the production of polycarbonates having low monomer content is disclosed. The process entails, in sequence, (i) transesterifying in the melt at least one dihydroxyaryl compound with at least one diaryl carbonate in the presence of at least one onium catalyst to produce a polycondensate that contains monomers, (ii) introducing into the polycondensate an inhibitor in an hypostoichiometric amount in relation to the catalyst and (iii) reducing in a finishing reactor the content of monomers in said polycondensate. The polycarbonate thus produced is characterized in that it contains less than 350 ppm of diphenyl carbonate, less than 40 ppm of 2,2-bis-(4-hydroxyphenyl)propane and less than 150 ppm of phenol.

Abstract: An improvement to the melt transesterification process for the preparation of polycarbonate is disclosed. The improvement entails adding to the process between its medium viscosity reactor and a high viscosity reactor at least one bridged ester of organic sulphur-containing acid.

Abstract: The invention describes a process for the preparation of polycarbonate. The process includes (a) transesterifying at least one aromatic dihydroxyaryl compound and a diaryl carbonate in the melt in the presence of a catalyst, (b) mixing the melt obtained in step (a) with a foaming agent (c) passing the mixture at 250 to 340° C. through inlet openings of a separating vessel at a rate of 0.1 to 20 kg/hour, to obtain a plurality of streams of foamed polycarbonate and degassing the streams of foamed polycarbonate in the separating vessel wherein the pressure is 0.1 to 20 mbar.

Abstract: A process for stripping volatile constituents from polymer melts is disclosed. The process entails introducing the polymer melt into a horizontally oriented cylindrical device that contains a plurality of perforated disks rotating about a common horizontally oriented, externally driven shaft bringing the melt and disks into contact in a manner calculated to constantly renew the surface of the melt to be stripped. Also disclosed is an apparatus suitable for the process.

Abstract: A thermoplastic molding composition comprising polycarbonate and 50 ppm to 300 ppm, in relation to the weight of the composition, of diphenyl carbonate is disclosed. The composition is especially suitable for the preparation of extruded sheets, in particular coextruded.

Abstract: A phenolic compound having a branched structure is disclosed. The compound conforms to HO—Ar1—X—Ar2—[Y—W]n  (1) wherein Ar1 and Ar2 independently denote an optionally substituted mononuclear or polynuclear aromatic moiety, X and Y independently denote a single bond or a divalent radical, W denotes an optionally substituted mononuclear or polynuclear aromatic moiety or an aliphatic or cycloaliphatic radical, and n is 1 to 5, is useful as a terminal group in polycarbonates, polyester carbonates and polyesters. Also disclosed is a process for producing such resins where the disclosed compound is a chain terminator.

Abstract: A thermoplastic molding composition comprising (A) 89 to 99 wt. % of a copolycarbonate and (B) 11 to 1 wt. % of a modifier is disclosed. The structure of the copolycarbonate contains 0.

Abstract: A process for the production of high molecular weight aliphatic polycarbonates is disclosed. The process entails a first stage wherein a low molecular weight aliphatic polycarbonate is prepared and a second stage where the low molecular weight aliphatic polycarbonate is condensed with diaryl carbonate in a melt transesterification process to form a high molecular weight aliphatic polycarbonate. The resulting high molecular weight aliphatic polycarbonate is suitable for the production of extrudates, films and molded articles.

Abstract: A process for preparing a melt transesterification catalyst is disclosed. The process entails (i) obtaining a phenol adduct of phosphonium phenolatein the form of crystalline solid and (ii) storing the solid phenol adductin a closed container at relative humidity of 30 to 70 % and at temperature of −30 to 50° C. The thus prepared catalyst is suitable in the production of polycarbonate in the melt transesterification process.

Abstract: A thermoplastic molding composition that features improved low-temperature properties and is thus suitable for application in exterior automotive parts is disclosed. The composition contains (A) 80 to 60 percent of a copolycarbonate wherein 65 to 75 mole percent of its structural units are derived from compounds of formula (I) wherein R1, R2, R3 and R4 independently of one another represents H, C1-C4-alkyl, phenyl, substituted phenyl or halogen, and wherein 25 to 35 mole percent of its structural units are derived from compounds of formula (II) where R5, R6, R7 and R8 independently one of the others denote H, CH3, Cl or Br and X is C1-C5-alkylene, C2-C5-alkylidene, C5-C6-cycloalkylene, C5-C10-cycloalkylidene and (B) 20 to 40 percent of a homopolycarbonate of bisphenol A having a melt flow rate, determined in accordance with ASTM D-1238 under 1.2 kg loading at 300° C. of 3 to 12 gm/10 minutes.

Abstract: A phenolic compound having a branched structure is disclosed.

Abstract: A thermoplastic molding composition that features improved low-temperature properties and is thus suitable for application in exterior automotive parts is disclosed.

Abstract: A process for the production of high molecular weight aliphatic polycarbonates is disclosed. The process entails a first stage wherein a low molecular weight aliphatic polycarbonate is prepared and a second stage where the low molecular weight aliphatic polycarbonate is condensed with diaryl carbonate in a melt transesterification process to form a high molecular weight aliphatic polycarbonate. The resulting high molecular weight aliphatic polycarbonate is suitable for the production of extrudates, films and molded articles.

Abstract: A process for preparing a melt transesterification catalyst is disclosed. The process entails (i) obtaining a phenol adduct of phosphonium phenolatein the form of crystalline solid and (ii) storing the solid phenol adductin a closed container at relative humidity of 30 to 70% and at temperature of −30 to 50° C. The thus prepared catalyst is suitable in the production of polycarbonate in the melt transesterification process.