Abstract: A catalyst system capable of producing a cyclic olefin polymer having a polar functional group and a high molecular weight with a high yield in which a catalyst is not deactivated due to polar functional groups of monomers, and a method of producing polymers using the same are provided. The catalyst system for polymerization of olefin according to the present invention has good thermal and chemical stability, and thus, in the method of preparing polyolefin using the catalyst system, the deactivation of a catalyst due to a polar functional group of the monomer can be prevented, and thus a high yield of the cyclic olefin polymer with a high molecular weight can be obtained when a ratio of the catalyst to the monomer is 1:5000, and the removal of a catalyst residue is not required.

Abstract: Provided is a method of preparing a phosphonium compound by reacting a protic phosphonium compound represented by [(R1)—P(R2)a(R2?)b]HX and a salt compound represented by [C][Ani]. Therefore, a phosphonium compound used as a cocatalyst for the preparation of a polar cyclic olefin polymer can be produced at high yield.

Abstract: Provided are a bridged metallocene compound particularly suitable for copolymerization of ethylene and alpha-olefin or cyclic olefin, a process of preparing the metallocene compound, and a process of preparing polyolefin using the metallocene compound. The bridged metallocene compound has low steric hindrance and good (co)polymerization activity, and thus, exhibits good activity in copolymerization of ethylene and alpha-olefin such as 1-hexene or 1-octene. Furthermore, the process of preparing the bridged metallocene compound is simplified, and thus, suitable for mass production.

Abstract: A method of producing a cyclic olefin polymer having a polar functional group and a high molecular weight with a high yield in which a catalyst is not deactivated due to polar functional groups, moisture and oxygen is provided. According to the olefin polymerization method, deactivation of a catalyst due to polar functional groups of monomers can be prevented, and thus a polyolefin having a high molecular weight can be prepared with a high yield, and the ratio of catalyst to monomer can be less than 1/5000 due to good activity of the catalyst, and thus removal of catalyst residues is not required.

Abstract: The present invention relates to a composition for forming a gate insulating layer of an organic thin film transistor comprising polyarylate, and an organic thin film transistor comprising a gate insulating layer, which is formed using the composition, in contact with an organic semiconductor channel.

Abstract: The present invention relates to a novel fulvene compound and a preparation method thereof, and more particularly to a fulvene compound having substituted groups in the 2- and 5-positions, prepared from an unsaturated ketone having a substituted group in the ?-position and a halogen atom in the ?-position, and a preparation method thereof. The present invention also relates to a metallocene catalyst having a substituted group in the ?-position carbon of the bridge of the cyclopentadienyl group only by reaction of a fulvene compound and an anion group including the cyclopentadienyl group, and a preparation method of a polyolefin copolymer using the same.

Abstract: The present invention relates to a novel fulvene compound and a preparation method thereof, and more particularly to a fulvene compound having substituted groups in the 2- and 5-positions, prepared from an unsaturated ketone having a substituted group in the ?-position and a halogen atom in the ?-position, and a preparation method thereof. The present invention also relates to a metallocene catalyst having a substituted group in the ?-position carbon of the bridge of the cyclopentadienyl group only by reaction of a fulvene compound and an anion group including the cyclopentadienyl group, and a preparation method of a polyolefin copolymer using the same.

Abstract: The present invention relates to a novel fulvene compound and a preparation method thereof, and more particularly to a fulvene compound having substituted groups in the 2- and 5-positions, prepared from an unsaturated ketone having a substituted group in the ?-position and a halogen atom in the ?-position, and a preparation method thereof. The present invention also relates to a metallocene catalyst having a substituted group in the ?-position carbon of the bridge of the cyclopentadienyl group only by reaction of a fulvene compound and an anion group including the cyclopentadienyl group, and a preparation method of a polyolefin copolymer using the same.

Abstract: Provided are a bimetallic zinc complex and a method of producing polycarbonate, including polymerizing an epoxy compound and carbon dioxide using the bimetallic zinc complex. The bimetallic zinc complex according to the present invention has a distance between zinc-zinc atoms, which is maintained in a limited range regardless of its concentration in a reaction medium for the polymerization. Thus, the bimetallic zinc complex can have a polymerization activity even at a high ratio of monomer/catalyst, thereby reducing a catalyst amount to be used, which is economically advantageous. Further, the bimetallic zinc complex can produce a high molecular weight polycarbonate.

Abstract: There are provided a method of simply preparing a 1,4,6-substituted, 1,4-substituted, 1,6-substituted, or 1-substituted fulvene compound, the intermediates of the fulvene compound, and a method of preparing an ansa-metallocene compound in which two cyclopentadienyl ligands are bridged by one carbon and there are substituents only at positions adjacent to the bridging point of a cyclopentadienyl ligand, using the fulvene compound.

Abstract: The present invention relates to a novel fulvene compound and a preparation method thereof, and more particularly to a fulvene compound having substituted groups in the 2- and 5-positions, prepared from an unsaturated ketone having a substituted group in the ?-position and a halogen atom in the ?-position, and a preparation method thereof. The present invention also relates to a metallocene catalyst having a substituted group in the ?-position carbon of the bridge of the cyclopentadienyl group only by reaction of a fulvene compound and an anion group including the cyclopentadienyl group, and a preparation method of a polyolefin copolymer using the same.