摘要:
Polyfluorene polymers and copolymers having substantial amounts (10-100%) of fluorenes coupled at the 2 and 5 positions of fluorene are useful as active layers in OLED devices where triplet energies >2.10 eV are required.
摘要:
Energy efficient optoelectronic devices include an electroluminescent layer containing a polymer made up of structural units of formula I and II; wherein R1 and R2 are independently C22-44 hydrocarbyl, C22-44 hydrocarbyl containing one or more S, N, O, P, or Si atoms, oxaalkylaryl, or a combination thereof; R3 and R4 are independently H, C1-44 hydrocarbyl or C1-44 hydrocarbyl containing one or more S, N, O, P, or Si atoms, or R3 and R4, taken together, form a C2-10 monocyclic or bicyclic ring containing up to three S, N, O, P, or Si heteroatoms; and X is S, Se, or a combination thereof.
摘要:
An organic light emitting device comprises an outcoupling layer having relatively high aspect ratio nanowires imbedded within an optically thick transparent high optical index film. The incorporation of nanowires increases the optical index of a light emitting assembly and provides a means for extracting light from a light emitting assembly of the organic light emitting device.
摘要:
Polyfluorene polymers and copolymers having substantial amounts (10-100%) of fluorenes coupled at the 2 and 5 positions of fluorene are useful as active layers in OLED devices where triplet energies >2.10 eV are required.
摘要:
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.
摘要:
The present invention relates to a method for the preparation of polycarbonate comprising preparing a polycarbonate by a melt process by reacting a diphenol and a diaryl carbonate in the presence of a catalytically effective amount of one or more alkali and or alkali earth metal salts of chelating agents. Suitable chelating agents include nitrilotriacetate and EDTA.
摘要:
A melt condensation polymerization process for preparing siloxane copolycarbonates is provided. The process includes reacting an aromatic dihydroxy compound, carbonic acid diester, hydroxyaryl terminated polydiorganosiloxane and catalyst with a salt.
摘要:
Polycarbonates containing low or undetectable levels of Fries rearrangement products and comprising repeat units derived from one or more of resorcinol, hydroquinone, methylhydroquinone, bisphenol A, and 4,4′-biphenol have been prepared by the melt reaction of one or more of the aforementioned dihydroxy aromatic compounds with an ester-substituted diaryl carbonate such as bis-methyl salicyl carbonate. Low, or in many instances undetectable, levels of Fries rearrangement products are found in the product polycarbonates obtained as the combined result of a highly effective catalyst system which suppresses the Fries reaction and the use of lower melt polymerization temperatures relative to temperatures required for the analogous polymerization reactions using diphenyl carbonate.
摘要:
The present invention relates to a method for the preparation of polycarbonate comprising preparing a polycarbonate by a melt process by reacting a diphenol and a diaryl carbonate in the presence of a catalytically effective amount of one or more alkali metal salts of oxoacids of sulfur.
摘要:
Polycarbonates containing low or undetectable levels of Fries rearrangement products and comprising repeat units derived from one or more of resorcinol, hydroquinone, methylhydroquinone, bisphenol A, and 4,4′-biphenol have been prepared by the melt reaction of one or more of the aforementioned dihydroxy aromatic compounds with an ester-substituted diaryl carbonate such as bis-methyl salicyl carbonate. Low, or in many instances undetectable, levels of Fries rearrangement products are found in the product polycarbonates obtained as the combined result of a highly effective catalyst system which suppresses the Fries reaction and the use of lower melt polymerization temperatures relative to temperatures required for the analogous polymerization reactions using diphenyl carbonate.