Abstract: Disclosed herein are a process for the refinement of nitrogen trifluoride gas and an adsorbent used therein. A nitrogen trifluoride (NF3) gas including carbon tetrafluoride (CF4) as an impurity is permeated into a bed of the zeolite 3 A, 4A or 5 A which is ion exchanged with alkali earth metal and is thermally treated at 150 to 600° C. for 0.5 to 100 hours so as to selectively adsorb nitrogen trifluoride onto the bed, followed by the desorption of the nitrogen trifluoride therefrom.

Abstract: Disclosed herein are a process for the refinement of nitrogen trifluoride gas and an adsorbent therefor. A nitrogen trifluoride (NF3) gas including carbon tetrafluoride (CF4) as an impurity is permeated into a bed of zeolite 3A, 4A or 5A which undergoes ion exchange and impregnation with alkali earth metal and is thermally treated at 150 to 600° C. for 0.5 to 100 hours so as to be able to selectively adsorb nitrogen trifluoride onto the bed, followed by the desorption of the nitrogen trifluoride therefrom.

Abstract: Disclosed is a flame-retardant polyester polymer dyeable with a cationic dye, a method of producing the same, a copolyester fiber using the same, and fiber products using the copolyester fiber. In the method, after a dimethyl isophthalate component containing metal sulfonate of Formula 2 separately reacts with ethylene glycol so that an extent of the ester interchange reaction is 95% or more to synthesize bis(hydroxyethyl terephthalate) containing metal sulfonate of Formula 3, bis(hydroxyethyl terephthalate) is fed so that a content of bis(hydroxyethyl terephthalate) is 0.01-5 mol % based on a diacid component in a polymer in a course of producing polyester, a phosphorus-based flame retardant of Formula 1 is fed so that a content of a phosphorus atom is 500-40000 ppm based on the polymer, and the mixture is copolymerized. The polyester polymer is dyeable with cationic dye while having excellent flame retardancy, and can be melt-spun like other polymers capable of being melt-spun.

Abstract: Disclosed herein are a process for the refinement of nitrogen trifluoride gas and an adsorbent therefor. A nitrogen trifluoride (NF3) gas including carbon tetrafluoride (CF4) as an impurity is permeated into a bed of zeolite 3 A, 4A or 5 A which undergoes ion exchange and impregnation with alkali earth metal and is thermally treated at 150 to 600° C. for 0.5 to 100 hours so as to be able to selectively adsorb nitrogen trifluoride onto the bed, followed by the desorption of the nitrogen trifluoride therefrom.

Abstract: The present invention relates to a process for preparing polyketone with improved catalytic activity and intrinsic viscosity, and specifically a process for preparing polyketone wherein an organometallic complex comprising acetate-palladium and 1,3-bis[bis(2-methoxy-5-methylphenyl)phosphino]propane is used as a catalyst component, and a mixed solvent of 70 to 90 vol % of acetic acid and 10 to 30 vol % of water is used as a liquid medium.

Abstract: The present invention relates to a process for preparing polyketone with improved catalytic activity and intrinsic viscosity, and specifically a process for preparing polyketone, in which as a catalyst component, an organometallic complex comprising palladium acetate, 1,3-bis[bis(2-methoxy-5-methylphenyl)phosphino]propane, and an anion of an acid with pKa of 4 or lower, as a liquid medium, a mixed solvent of methanol and 1000 to 10000 ppm of water, and upon polymerization, benzothiazole or benzophenone is added.

Abstract: The present invention relates to a high strength polyethylene-2,6-naphthalate fiber produced by a method comprising controlling the stress-strain curve and fine structure of an undrawn yarn such that the drawability of the undrawn yarn in a drawing step is improved. The industrial polyethylene-2,6-naphthalate fiber with high strength according to the present invention shows high strength and low shrinkage, and a treated cord formed from this fiber has improved dimensional stability and high strength, such that it can be advantageously employed as a fibrous reinforcement material of rubber products such as tires.

Abstract: This invention relates to a method of preparing cellulose solution which is homogeneous at relatively low temperature, in which a small amount of cellulose powder or polyvinylalcohol is dissolved in the liquid-state, concentrated N-methylmorpholine-N-oxide (hereinafter, referred to as ‘NMMO’) so as to lower the solidifying temperature of NMMO, and then, the resulting solution and cellulose powder are fed into an extruder so as to be mixed, swollen and melted in the extruder.

Abstract: This invention relates to a method of preparing cellulose solution which is homogeneous at relatively low temperature, in which a small amount of cellulose powder or polyvinylalcohol is dissolved in the liquid-state, concentrated N-methylmorpholine-N-oxide (hereinafter, referred to as ‘NMMO’) so as to lower the solidifying temperature of NMMO, and then, the resulting solution and cellulose powder are fed into an extruder so as to be mixed, swollen and melted in the extruder.

Abstract: The present invention relates to a method for making highly homogenized cellulose solution, wherein the cellulose solution is obtained by obtaining a solidified N-methylmorphorine-N-oxide (hereinafter, referred to as ‘NMMO’) hydrates which is solidified a liquid-state NMMO hydrates comprising 10 to 18% by weight water by using a simple screw-type feeder and by controlling the temperature, feeding the solidified NMMO into a twin-screw type extruder continuously, obtaining a cellulose solution which is fully swelled in a few minutes by dispersing and mixing with cellulose powder in the twin-screw type extruder, and extruding a highly homogenized cellulose solution by feeding the obtained cellulose solution into a melting zone of the extruder to melting the cellulose solution in a few minutes by minimum heat and shear force.

Abstract: The present invention relates to a high strength polyethylene-2,6-naphthalate fiber produced by a method comprising controlling the stress-strain curve and fine structure of an undrawn yarn such that the drawability of the undrawn yarn in a drawing step is improved. The industrial polyethylene-2,6-naphthalate fiber with high strength according to the present invention shows high strength and low shrinkage, and a treated cord formed from this fiber has improved dimensional stability and high strength, such that it can be advantageously employed as a fibrous reinforcement material of rubber products such as tires.

Abstract: The present invention relates to a method for making highly homogenized cellulose solution, wherein the cellulose solution is obtained by obtaining a solidified N-methylmorphorine-N-oxide (hereinafter, referred to as ‘NMMO’) hydrates which is solidified a liquid-state NMMO hydrates comprising 10 to 18% by weight water by using a simple screw-type feeder and by controlling the temperature, feeding the solidified NMMO into a twin-screw type extruder continuously, obtaining a cellulose solution which is fully swelled in a few minutes by dispersing and mixing with cellulose powder in the twin-screw type extruder, and extruding a highly homogenized cellulose solution by feeding the obtained cellulose solution into a melting zone of the extruder to melting the cellulose solution in a few minutes by minimum heat and shear force.

Abstract: This invention relates to a method of preparing cellulose solution which is homogeneous at relatively low temperature, in which a small amount of cellulose powder or polyvinylalcohol is dissolved in the liquid-state, concentrated N-methylmorpholine-N-oxide (hereinafter, referred to as ‘NMMO’) so as to lower the solidifying temperature of NMMO, and then, the resulting solution and cellulose powder are fed into an extruder so as to be mixed, swollen and melted in the extruder.

Abstract: Disclosed is a flame-retardant polyester polymer dyeable with a cationic dye, a method of producing the same, a copolyester fiber using the same, and fiber products using the copolyester fiber. In the method, after a dimethyl isophthalate component containing metal sulfonate of Formula 2 separately reacts with ethylene glycol so that an extent of the ester interchange reaction is 95% or more to synthesize bis(hydroxyethyl terephthalate) containing metal sulfonate of Formula 3, bis(hydroxyethyl terephthalate) is fed so that a content of bis(hydroxyethyl terephthalate) is 0.01-5 mol % based on a diacid component in a polymer in a course of producing polyester, a phosphorus-based flame retardant of Formula 1 is fed so that a content of a phosphorus atom is 500-40000 ppm based on the polymer, and the mixture is copolymerized. The polyester polymer is dyeable with cationic dye while having excellent flame retardancy, and can be melt-spun like other polymers capable of being melt-spun.

Abstract: The present invention relates to a high tenacity polyethylene naphthalate fiber containing a silica compound. This fiber is produced by a method comprising the steps of: (A) melt-spinning a solid phase-polymerized polyethylene-2,6-naphthalate chip containing ethylene-2,6-naphthalate units at more than 85 mole % and a silica compound and having an intrinsic viscosity of 0.70-1.20, to produce a melt-spun yarn; (B) passing the melt-spun yarn through a retarded cooling zone and a cooling zone to solidify the yarn; (C) withdrawing the yarn at such a speed that the undrawn yarn has a birefringence of 0.001-0.1; and (D) subjecting the undrawn yarn to multi-stage drawing at a total draw ratio of at least 1.5 and a drawing temperature of 50-250° C.

Abstract: The present invention relates to a method for making highly homogenized cellulose solution, wherein the cellulose solution is obtained by obtaining a solidified N-methylmorphorine-N-oxide (hereinafter, referred to as ‘NMMO’) hydrates which is solidified a liquid-state NMMO hydrates comprising 10 to 18% by weight water by using a simple screw-type feeder and by controlling the temperature, feeding the solidified NMMO into a twin-screw type extruder continuously, obtaining a cellulose solution which is fully swelled in a few minutes by dispersing and mixing with cellulose powder in the twin-screw type extruder, and extruding a highly homogenized cellulose solution by feeding the obtained cellulose solution into a melting zone of the extruder to melting the cellulose solution in a few minutes by minimum heat and shear force.

Abstract: This invention relates to a method of preparing cellulose solution which is homogeneous at relatively low temperature, in which a small amount of cellulose powder or polyvinylalcohol is dissolved in the liquid-state, concentrated N-methylmorpholine-N-oxide (hereinafter, referred to as ‘NMMO’) so as to lower the solidifying temperature of NMMO, and then, the resulting solution and cellulose powder are fed into an extruder so as to be mixed, swollen and melted in the extruder.

Abstract: The present invention relates to a high strength polyethylene-2,6-naphthalate fiber produced by a method comprising controlling the stress-strain curve and fine structure of an undrawn yarn such that the drawability of the undrawn yarn in a drawing step is improved. The industrial polyethylene-2,6-naphthalate fiber with high strength according to the present invention shows high strength and low shrinkage, and a treated cord formed from this fiber has improved dimensional stability and high strength, such that it can be advantageously employed as a fibrous reinforcement material of rubber products such as tires.

Abstract: The present invention relates to a high tenacity, high modulus and low shrinkage lyocell multifilament yarn suitable for use in tire cords and MRG (mechanical rubber goods). The lyocell multifilament yarn is a cellulose-based fiber for industrial applications, which is produced by dissolving pulp having a degree of polymerization (DPW) of 700-2,000 and preferably 800-1,400, and a ?-cellulose content of more than 90% and preferably more than 92%, in N-methylmorpholine N-oxide (NMMO) hydrate, at a pulp concentration of 5-15% by weight and preferably 8-13% by weight. The lyocell monofilament according to the present invention is characterized by the following stress-strain profile: (1) the lyocell monofilament analyzed after drying is elongated by less than 3.0% and has an initial modulus of 150-400 g/d, when it was subjected to an initial stress of 3.0 g/d; (2) it is elongated by 3.0-7.0% when it was subjected to a stress greater than the initial stress but smaller than 6.

Abstract: The present invention relates to crosslinked polyvinyl alcohol raw cord and method for producing the same, and more particularly, to crosslinked polyvinyl alcohol fiber, in which PVA resin having a degree of polymerization of more than 1,000 and a degree of saponification of more than 97.0 mol % is dissolved in dimethyl sulfoxide, the solution is subjected to dry and wet gel spinning using methanol as a coagulation solution, drawn and thermally treated, the resulting polyvinyl alcohol drawn yarn with 500-3,000 deniers is twisted to produce a cabling yarn, the cabling yarn is plied into a 2-ply or 3-ply yarn to produce a raw cord, the raw cord is wound on a bobbin for crosslinking and crosslinked in an aqueous crosslinking solution containing an aromatic aldehyde compound and an acid catalyst. Moreover, the present invention relates to a crosslinker-introducing apparatus, which is used in the above method and can effectively induce the crosslinking reaction of the wound raw cord.