Abstract:
Example embodiments relate to a method of manufacturing a polymer dispersed liquid crystal (PDLC) display device including dichroic dye. The method may include filling a mixture solution including liquid crystals, a photopolymerizable material, dichroic dyes, and liquid crystalline polymers in a space between a first electrode and a second electrode that face each other; applying an electric field between the first electrode and the second electrode; and arranging the dichroic dyes in the mixture solution.
Abstract:
A method for preparing polyolefin from alpha-olefin with high productivity using an internal circulating fluidized bed polymerization reactor is disclosed. The method for gas-phase polymerization of alpha-olefin comprising the steps of: supplying circulation gas including one or more alpha-olefins and inert gas into a polymerization reactor; polymerizing the alpha-olefin to polyolefin in two separated polymerization areas in the polymerization reactor; and discharging produced polyolefin from the polymerization reactor. The polymerization reactor is divided into the two polymerization areas by a draft tube, and an inside of the draft tube forms a riser where growing polyolefin polymers move up in fast fluidization, and an outside of the draft tube forms an annulus where the polyolefin polymers passing the riser move down by gravity, and the polyolefin polymers passing the annulus are introduced to a lower part of the riser again, so that the polyolefin polymers are polymerized during circulating between the riser and the annulus.
Abstract:
A multinuclear transition metal compound which has two or more catalytic active sites, and is useful in preparing the olefin polymer and copolymer, is disclosed. The multinuclear transition metal compound for olefin polymerization includes two or more metals, and at least one ligand having a cyclopentadienyl moiety, which connects the two or more metals. The preferable multinuclear transition metal catalyst for olefin polymerization includes the first transition metal, the first η ligand having a cyclopentadienyl moiety, which is coordinated to the first transition metal, and the second transition metal to which the second η ligand having a cyclopentadienyl moiety is coordinated, wherein the second transition metal is bonded to the first η-ligand via a sigma (σ) bond.
Abstract:
The present invention relates to supported metallocene catalysts and to new processes for preparing them and olefin polymerization therewith. Specifically, this invention relates to supported catalyst benefiting from the penetration and homogeneous distribution of catalyst components containing one or more metallocenes and activators within porous support particles. A new process for preparing the catalyst of the invention provides for a supported metallocene catalyst, wherein one or more metallocenes and activator, a solvent capable of dissolving them and a porous support are mutually contacted to form a slurry and a sonic wave or vibrating wave in the frequency range of 1-10,000 kHz is applied to the slurry and the solvent is removed and the resultants are dried. The catalyst are useful for olefin polymerization in a slurry and gas phase polymerization process.
Abstract:
There are disclosed new metallocene compounds and catalysts for olefin polymerization. The metallocene compound is a complex of transition metal and cyclopentadienyl-type ligands substituted with silacycloalkyl group. The metallocene catalyst comprises the above metallocene compound and at least one activator such as aluminoxanes, aromatic boron compounds substituted with fluoride, and modified clays. The metallocene catalyst can be used for polymerization of olefin in liquid phase, slurry phase or gas phase process.
Abstract:
A method for preparing polyolefin from alpha-olefin with high productivity using an internal circulating fluidized bed polymerization reactor is disclosed. The method for gas-phase polymerization of alpha-olefin comprising the steps of: supplying circulation gas including one or more alpha-olefins and inert gas into a polymerization reactor; polymerizing the alpha-olefin to polyolefin in two separated polymerization areas in the polymerization reactor; and discharging produced polyolefin from the polymerization reactor. The polymerization reactor is divided into the two polymerization areas by a draft tube, and an inside of the draft tube forms a riser where growing polyolefin polymers move up in fast fluidization, and an outside of the draft tube forms an annulus where the polyolefin polymers passing the riser move down by gravity, and the polyolefin polymers passing the annulus are introduced to a lower part of the riser again, so that the polyolefin polymers are polymerized during circulating between the riser and the annulus.
Abstract:
Example embodiments relate to a method of manufacturing a polymer dispersed liquid crystal (PDLC) display device including dichroic dye. The method may include filling a mixture solution including liquid crystals, a photopolymerizable material, dichroic dyes, and liquid crystalline polymers in a space between a first electrode and a second electrode that face each other; applying an electric field between the first electrode and the second electrode; and arranging the dichroic dyes in the mixture solution.
Abstract:
A method for preparing polyolefin from alpha-olefin with high productivity using an internal circulating fluidized bed polymerization reactor is disclosed. The method for gas-phase polymerization of alpha-olefin comprising the steps of: supplying circulation gas including one or more alpha-olefins and inert gas into a polymerization reactor; polymerizing the alpha-olefin to polyolefin in two separated polymerization areas in the polymerization reactor; and discharging produced polyolefin from the polymerization reactor. The polymerization reactor is divided into the two polymerization areas by a draft tube, and an inside of the draft tube forms a riser where growing polyolefin polymers move up in fast fluidization, and an outside of the draft tube forms an annulus where the polyolefin polymers passing the riser move down by gravity, and the polyolefin polymers passing the annulus are introduced to a lower part of the riser again, so that the polyolefin polymers are polymerized during circulating between the riser and the annulus.
Abstract:
Olefin polymerization catalysts which are obtained by a simple method and exhibits mild onset of polymerization, improved reaction kinetic profile, and high productivity over an increased catalyst lifetime while a polymer product characterized by good morphology and high bulk density and olefin polymerization processes using the same are disclosed. The olefin polymerization catalyst according to the present invention comprises an organometallic compound of the following Formula 1; aluminoxane; and an organic transition metal compound of the following Formula 2: M1R1lR2mR3n or R2mR3nM1R1l-Q-R1lM1R2mR3n [Formula 1] in Formula 1, M1 is selected from the group consisting of Group 2A, 2B and 3B of the Periodic Table, R1 is cyclic hydrocarbyl group of 5 to 30 carbon atoms, R2 and R3 are independently hydrocarbyl group of 1 to 24 carbon atoms, l is an integer of more than 1, m and n are independently an integer of 0 to 2, l+m+n is equal to the valence of M1, Q is a divalent group; M2R4pXq [Formula 2] in Formula 2, M2 is Ti, Zr or Hf, R4 is cyclic hydrocarbyl group of 5 to 30 carbon atoms, X is halogen atom, p is an integer of 0 or 1, q is an integer of 3 or 4, p+q is equal to the valence of metal M2.
Abstract:
An olefin polymerization catalyst which includes an organometallic compound of the following Formula 1; aluminoxane; and an organic transition metal compound of the following Formula 2: M1R11R2mR3n or R2mR3nM1R11M1R2mR3n [Formula 1 ] in Formula 1, M1 is selected from the group consisting of Group 2A, 2B and 3A of the Periodic Table, R1 is cyclic hydrocarbyl group of 5 to 30 carbon atoms, R2 and R3 are independently hydrocarbyl group of 1 to 24 carbon atoms, l is an integer of more than 1, m and n are independently an integer of 0 to 2, l+m+n is equal to the valence of M1, Q is a divalent group; M2R4pXq [Formula 2 ] in Formula 2, M2 is Ti, Zr or Hf; R4 is cyclic hydrocarbyl group of 5 to 30 carbon atoms, X is halogen atom, p is an integer of 0 or 1, q is an integer of 3 or 4, p+q is equal to the valence of metal M2.