摘要:
Aromatic polycarbonate having a reduced discoloration and improved heat stability, hue, etc. is provided by keeping a pressure in a raw material melting vessel and the linear velocity of a gas in a transporting piping in a specific range, keeping the concentration of a nitrogen-containing basic compound in a specific range, recycling a byproduct containing specific amounts of impurities, suppressing the amounts of a nitrogen-containing basic compound, metallic elements and a silicic acid derivative in the carbonic acid diester at specific values or less, prescribing the material quality of the reaction facilities, and/or forming an oxide layer at the inner wall surfaces of the reaction facilities.
摘要:
A polycarbonate resin composition which is excellent in thermal stability such as color retention at the time of melt molding, for example, the prevention of yellowing, and moldability such as releasability and transferability and therefore particularly suitable for the production of precision optical moldings such as optical disk substrates and lenses. The polycarbonate resin composition comprises (A) an aromatic polycarbonate, and (B) a cyclic carbonate compound, a monoester compound of a divalent aliphatic alcohol having 3 to 14 carbon.atoms and an aliphatic monocarboxylic acid having 12 to 24 carbon atoms, or an ether compound obtained by converting at least one hydroxyl group of a polyvalent aliphatic alcohol having 3 to 14 carbon atoms into an aliphatic oxy group having 1 to 18 carbon atoms, or (C) a partial ester compound of an aliphatic alcohol having a valence of 2 to 6 and 2 to 14 carbon atoms and an aliphatic monocarboxylic acid having 12 to 24 carbon atoms, a cyclic phenol compound or a compound selected from hydrochloric acid, phosphoric acid, phosphorous acid, boric acid, and amine salts and ammonium salts thereof.
摘要:
To provide a carbon fiber reinforcement having excellent thermal conductivity and mechanical properties which is manufactured by mixing together two different types of pitch-based carbon short fibers having a ratio of the degree of filament diameter distribution to average fiber diameter of 0.05 to 0.2 and a fiber length of 20 to 6,000 μm which differ from each other in average fiber diameter or by mixing one of them with a pitch-based carbon fiber web to improve dispersibility into a matrix resin or increase the dispersion ratio of the pitch-based carbon short fibers.
摘要:
A carbon fiber composite sheet comprising a pitch-based carbon fiber web and a matrix resin, wherein carbon fibers constituting the pitch-based carbon fiber web have a crystallite size in the hexagonal net plane direction of 5 nm or more and a thermal conductivity in the thickness direction of 1 W/(m·K) or more. This carbon fiber composite sheet is used for radio shielding and heat conduction.
摘要:
To provide a carbon fiber reinforcement having excellent thermal conductivity and mechanical properties which is manufactured by mixing together two different types of pitch-based carbon short fibers having a ratio of the degree of filament diameter distribution to average fiber diameter of 0.05 to 0.2 and a fiber length of 20 to 6,000 μm which differ from each other in average fiber diameter or by mixing one of them with a pitch-based carbon fiber web to improve dispersibility into a matrix resin or increase the dispersion ratio of the pitch-based carbon short fibers.
摘要:
To provide a carbon fiber reinforcement having excellent thermal conductivity and mechanical properties which is manufactured by mixing together two different types of pitch-based carbon short fibers having a ratio of the degree of filament diameter distribution to average fiber diameter of 0.05 to 0.2 and a fiber length of 20 to 6,000 μm which differ from each other in average fiber diameter or by mixing one of them with a pitch-based carbon fiber web to improve dispersibility into a matrix resin or increase the dispersion ratio of the pitch-based carbon short fibers.
摘要:
A carbon fiber composite sheet obtained by combining a carbon fiber aggregate with a thermosetting resin component selected from the group consisting of thermosetting silicone-based gel components, thermosetting epoxy resin components and thermosetting silicone resin components, and then curing the thermosetting resin component, the carbon fiber composite sheet having crystallite sizes of at least 5 nm in the direction of growth of the hexagonal mesh surface of the carbon fibers composing the carbon fiber aggregate, and the carbon fiber composite sheet having a thermal conductivity of at least 2 W/(m·K).
摘要:
A process for the production of an aromatic polycarbonate, which comprises polycondensing an aromatic dihydroxy compound and a diaryl carbonate in the presence, as a polycondensation catalyst, of at least one alkali metal salt selected from the group consisting of alkali metal salts of ate-complexes of a metal element, which is silicon, germanium, stannum or plumbum, and alkali metal salts of oxoacids of said metal elements. The above aromatic polycarbonate is almost free from being colored, is also almost free from a decrease in polymerization degree when molded, and is further almost free from forming branches and insolubles.
摘要:
A process for the production of a stabilized polycarbonate which comprises melt-polycondensing an aromatic dihydroxy compound and a carbonic acid diester in the presence of a polycondensation catalyst and then, after the reaction mixture shows an intrinsic viscosity of at least 0.1, adding at least one stabilizer selected from the group consisting of specific compounds having a sulfanate group and a sulfonic acid anhydride group in an amount of 0.01 to 500 ppm of a polycarbonate to be formed, to form a polycarbonate having a desired intrinsic viscosity.
摘要:
A carbon fiber composite sheet obtained by combining a carbon fiber aggregate with a thermosetting resin component selected from the group consisting of thermosetting silicone-based gel components, thermosetting epoxy resin components and thermosetting silicone resin components, and then curing the thermosetting resin component, the carbon fiber composite sheet having crystallite sizes of at least 5 nm in the direction of growth of the hexagonal mesh surface of the carbon fibers composing the carbon fiber aggregate, and the carbon fiber composite sheet having a thermal conductivity of at least 2 W/(m·K).