Abstract: Polycarbonate compositions incorporating long chain alkylphenol endgroups, for example cardanol, show enhanced pit replication characteristics when molded into optical disks. The enhancement in molding performance is especially pronounced at the shortest mold cycle times tested. Thus, a blend of 75 parts by weight bisphenol A polycarbonate 92 percent encapped with phenol, and 25 parts by weight bisphenol A polycarbonate about 100 percent endcapped with cardanol showed enhanced pit replication performance in optical disk molding trials relative to the same bisphenol A polycarbonate alone and analogous blends utilizing short chain alkylphenols.

Abstract: A method for preparing a polycarbonate comprises preparing a free hydroxyl-containing polycarbonate and reacting the hydroxyl-containing polycarbonate with a mixture of (B) a symmetrical optionally activated aromatic carbonic acid diester and (C) an optionally substituted aromatic hihydroxy compound, diol or diacid. A copolymerization reagent comprises a mixture of (B) a symmetrical optionally activated aromatic carbonic acid diester and (C) an optionally substituted aromatic hihydroxy compound, diol or diacid. A copolymer comprises [polycarbonate]x moieties; (B) [symmetrical optionally activated aromatic carbonic acid diester]y moieties and (C) [optionally substituted aromatic hihydroxy compound, diol or diacid]z moieties, wherein x, y and z are mole percents of the copolymer.

Abstract: A process for preparing an end-capped polycarbonate comprises melt reacting an aromatic dihydroxy compound, a carbonic acid diester, and optionally a catalyst in a prepolymerization vessel to form a polycarbonate product; transferring the polycarbonate product from the prepolymerization vessel; mixing the polycarbonate product with an end-capping agent under hermetic seal at a pressure of at least about 760 mm Hg; and transferring the polycarbonate product and end-capping agent mixture to a postpolymerization vessel to endcap the polycarbonate product.

Abstract: A method for end-capping polycarbonate resins, comprising the step of processing a mixture comprising a polycarbonate having free hydroxyl-end groups and an end-capping reagent in a melt transesterification reaction to produce a polycarbonate resin, wherein the end-capping reagent comprises a mixture of:

Abstract: Polycarbonate resin containing reduced levels of reaction by-products can be prepared by adding to the polycarbonate a scavenging agent having the formula: wherein R1 is alkoxy, phenoxy, benzyloxy or phenyl, and R2 is a substituted or unsubstituted C1-C30 alkyl group, C6-C30 aryl group, C7-C30 aralkyl group or C6-C30 aryloxy group and processing the resulting mixture at an elevated temperature and for a period of time such that the scavenging agent reacts with linear Fries products to produce capped linear Fries products, and with residual phenols (monohydric or dihydric) to produce capped phenols and ortho-substituted phenols.

Abstract: Polycarbonate having increased end-cap levels is made by adding an end-capping agent to the polycarbonate, preferably after the polycarbonate has reached a number-average molecular weight of about 2,000 to 15,000 Dalton.

Abstract: A method for end-capping polycarbonate resins, comprising the step of processing a mixture comprising a polycarbonate having free hydroxyl-end groups and an end-capping reagent in a melt transesterification reaction to produce a polycarbonate resin, wherein the end-capping reagent comprises a mixture of:(a) at least one species of a symmetrical activated aromatic carbonate, and (b) at least one species of an optionally-substituted phenol, whereby said end-capping reagent reacts with at least some of the free hydroxyl end-groups of the polycarbonate to produce an end-capped polycarbonate resin.

Abstract: Polycarbonate resin containing reduced levels of reaction by-products can be prepared by adding to the polycarbonate a scavenging agent having the formula: 1

Abstract: A process for preparing an end-capped polycarbonate comprises melt reacting an aromatic dihydroxy compound, a carbonic acid diester, and optionally a catalyst in a prepolymerization vessel to form a polycarbonate product; transferring the polycarbonate product from the prepolymerization vessel; mixing the polycarbonate product with an end-capping agent under hermetic seal at a pressure of at least about 760 mm Hg; and transferring the polycarbonate product and end-capping agent mixture to a postpolymerization vessel to endcap the polycarbonate product.

Abstract: In various embodiments the present invention comprises 2,4,6-trisubstituted-1,3,5-triazine capping agents comprising one, two, or three leaving groups as substituents with any remaining substituents being essentially inert to reaction with a nucleophilic group on a polymer or monomer, or reactive with a nucleophilic group on a polymer or monomer at a slower rate than any leaving group. The invention also comprises polymers or monomers with nucleophilic groups capped with a triazine moiety. Still other embodiments of the invention comprise processes for capping nucleophilic groups in a polymer or monomer which comprises combining and reacting the polymer or monomer with a triazine-comprising capping agent.

Abstract: This invention provides certain polycarbonates and polycarbonate blends useful in optical article applications. In a preferred embodiment, copolymers of, for example, certain ortho substituted bisphenol A-based polycarbonates and bisphenol A, optionally further comprising polycarbonate residues derived from ortho subsitituted spirobiindane compounds and alkylene or cycloalkylene diacid moieties. In a further embodiment, the invention provides copolymers of certain ortho-substituted bisphenol A moieties and ortho-substituted spirobiindane moieties. Also provided are optical articles comprised of the copolymers and blends of the invention. We have found that such copolymers and blends exhibit superior dimensional stability when exposed to water or moisture.

Abstract: Polycarbonate having increased end-cap levels is made by adding an end-capping agent to the polycarbonate, preferably after the polycarbonate has reached a number-average molecular weight of about 2,000 to 15,000 Dalton. The end-capping agent has the formula: wherein R1 is a phenyl, phenoxy, benzyl, or benzyloxy and R2 is selected from the group consisting of C1-C30 alkyl, C1-C30 alkoxy, C6-C30 aryl, C6-C30 aryloxy, C7-C30 aralkyl, and C7-C30 aralkyloxy.

Abstract: The invention relates to a method for the production of a branched polycarbonate composition, having increased melt strength, by late addition of branch-inducing catalysts to the polycarbonate oligomer in a melt polycondensation process. Surprisingly, it has been found that by adding branch-inducing catalysts, such as alkali metal compounds and/ or alkaline earth metal compounds, to the melt polycarbonate oligomer at a later stage of the melt polycondensation process, preferably after the oligomer has reached an average molecular weight of between about 3,000 and 30,000 g/mole, a unique branched polycarbonate composition is formed that has improved properties. It is believed that the addition of the branch-inducing catalysts at the later stages of the process produces a branched polycarbonate composition having longer chains between the branching points, and thus a new composition is produced. The invention also relates to various applications of the branched polycarbonate composition.

Abstract: A method for end-capping polycarbonate resins, comprising the step of processing a mixture comprising a polycarbonate having free hydroxyl-end groups and an end-capping reagent in a melt transesterification reaction to produce a polycarbonate resin, wherein the end-capping reagent comprises a mixture of:(a) at least one species of a symmetrical activated aromatic carbonate, and (b) at least one species of a symmetrical non-activated aromatic carbonate, whereby said end-capping reagent reacts with at least some of the free hydroxyl end-groups of the polycarbonate to produce an end-capped polycarbonate resin.

Abstract: A poly(carbonate-co-ester) block copolymer is synthesized using synthetic strategies that can be incorporated into conventional melt facilities that are commonly used in the production of polycarbonate polymers. The polycarbonate block of the poly(carbonate-co-ester) copolymer is derived from a polycarbonate reaction mixture comprising an aromatic dihydroxy compound and a carbonic acid diester, such as bisphenol A and diphenyl carbonate, respectively. The second block of the copolymer is derived from a polyester prepolymer, the polyester prepolymer comprising a diol, diacid or diester, and at least one monomer that is selected to advantageously incorporate desired properties into the poly(carbonate-co-ester) copolymer. The polyester prepolymer is introduced to the polycarbonate reaction mixture to form the poly(carbonate-co-ester) copolymer. Properties of the copolymer can be altered by varying numerous conditions of the reaction.

Abstract: A process for the production of polycarbonate having increased end-cap levels, the process comprising adding a terminal blocking agent of the formula: 1

Abstract: A process for the production of polycarbonate having increased end-cap levels and controlled molecular weight build-up, the process comprising adding a terminal blocking agent of the formula: 1

Abstract: A process for the production of polycarbonate by melt-polycondensing an aromatic dihydroxy compound and diphenylcarbonate, the process comprising adding the to polycarbonate under melt conditions a compound of the formula (1): 1

Abstract: A process for the production of a branched aromatic polycarbonate that includes adding a branching agent to a polycarbonate oligomer, and producing a branched aromatic polycarbonate having a melt index ratio greater than an aromatic polycarbonate produced from the polycarbonate oligomer without the addition of the branching agent. The branching agent has the formula (I): AGy  (I) wherein A is a C1-20 polymethylene, C2-20 alkylene or alkylidene, C5-36 cycloalkylene or cycloalkylidene, C6-36 arylene or alkylarylene, or C3-36 arylalkylene, wherein G is a monovalent C6-C30 hydrocarbon having at least one hydroxyl group bonded directly to an aromatic or cycloaliphatic ring and y is an integer greater than 2, and wherein each G may be the same or different.