task-specific ionic liquid via C(sp3)–O and C(sp2)–Obondcleavage of two different types of ethers for the assembly of structurally diverse 4-arylisoxazoles is described. Both the basic ionic liquid [C3NH2mim]Br and NHC–Pd catalyst IPr–Pd–Im–Cl2 played an important role in this transformation. Notably, this new approach provides a practical and straightforward route to access a broad range of privileged 4-arylisoxazole
Process for producing aromatic polyether ketones and polythioether ketones
申请人:MITSUBISHI KASEI CORPORATION
公开号:EP0135938A2
公开(公告)日:1985-04-03
A process for producing aromatic polyether ketones and polythioether ketones, which comprises reacting aromatic ethers or thioethers represented by the general formula:
where each of R1 to R12 is a hydrogen atom, a halogen atom, a hydrocarbon group or an alkoxy group, n is an integer of 0 to 5, and X is an oxygen atom or a sulfur atom, with phosgene in aprotic solvent having a dielectric constant of lower than 20 and a dipole moment of lower than 3.0 in the presence of anhydrous halides of metals of Group III in the periodic table as a catalyst.
Large-diameter optical disk substrate made of polycarbonate, process for its production and mold therefore
申请人:DAICEL CHEMICAL INDUSTRIES, LTD.
公开号:EP0155452A1
公开(公告)日:1985-09-25
The invention concerns a large-diameter optical disk substrate, a process for its production and an injection mold therefore.
本发明涉及一种大直径光盘基板、其生产工艺和注塑模具。
Process for the preparation of polyarylene sulfide and an apparatus for the preparation thereof
申请人:Tonen Chemical Corporation
公开号:EP0547718A2
公开(公告)日:1993-06-23
High molecular weight polyarylene sulfide is prepared by reacting an alkali metal sulfide with a dihaloaromatic compound in an organic amide solvent, wherein a gaseous phase part of a reactor is cooled to thereby condense a part of a gaseous phase in the reactor, and the condensed liquid is refluxed to a liquid phase in the reactor. Higher molecular weight is attained by copolymerization with 0.005 to 1.5 mole percent, based on the alkali metal sulfide, of a polyhaloaromatic compound.
Process for controlling a particle size of polyarylene sulfide and polyarylene sulfide thus produced
申请人:Tonen Chemical Corporation
公开号:EP0598449A2
公开(公告)日:1994-05-25
A particle size of polyarylene sulfide obtained in polymerization is controlled by a process characterized in that a gaseous phase part of a reactor is cooled or heated after starting decreasing a temperature of a reaction system o an end of precipitation of polyarylene sulfide formed In an embodiment, a water content in the reaction system is 0.8 to 1.7 moles per mole of the alkali metal sulfide; the gaseous phase part of the reactor is cooled in a polymerization stage to thereby condense a part of a gaseous phase in the reactor and the condensed liquid is refluxed to a liquid phase in the reactor; and the gaseous phase part is only cooled after starting decreasing the temperature of the reaction system, whereby high molecular weight polyarylene sulfide suitable for powder coating is formed, which has a weight average molecular weight of at least 30,000 and an average particle size of 50 to 80 µm, wherein particles of 40 to 150 µm account for at least 90 % by weight of the whole particles in a particle size distribution, and the amount of particles of 180 µm or more is 0.5 % 1by weight or less.