Abstract: An apparatus and a method for effectively recovering acetic acid and catalyst from a mother liquor discharged from a series of processes including an oxidation process, a crystallization process and a solid-liquid separation process, in a continuous process for preparing naphthalenedicarboxylic acid by oxidizing dimethylnaphthalene in the presence of an oxygen-containing gas and an acetic acid solvent, using a catalyst system comprising a transition metal such as cobalt or manganese, and a bromine-based compound, are provided.

Abstract: It is an object of the present invention to provide a hybrid dip cord consisting of rayon yarn and lyocell yarn to apply to the carcass ply or cap ply (belt reinforced layer) of pneumatic radial tire used in a car and a radial tire using the same. And also, according to the present invent the hybrid dip cord and the radial tire for application to the carcass ply or cap ply (belt reinforced layer) of pneumatic radial tire used in cars are produced by means of the following steps; imparting S direction twist of 20 to 200 TPM yarn number to one rayon yarn to produce a pre-yarn, imparting twist to said one rayon pre-yarn and one non-twisted lyocell respectively to produce a ply twist yarn, and imparting cable twist to two ply of ply twist yarn made from combination of said ply twist yarn or impart cable twist to a ply twist yarn to be produced by regulating low the twist number of one lyocell yarn and the rayon yarn to one lyocell as 20 to 200 TPM when the ply twist processes.

Abstract: A method for producing naphthalenedicarboxylic acid comprising the steps of: dissolving 2,6-dimethylnaphthalene in acetic acid solvent; oxidizing the product from the dissolution process using oxygen and a diluent gas; crystallizing naphthalenedicarboxylic acid that has been produced from the oxidation process; and separating the crystallized naphthalenedicarboxylic acid, wherein the amount of the diluent gas being discharged from and recycled to the oxidation process is controlled during the oxidation process, and the amount of mother liquor being recycled to the dissolution process after crystallization is controlled during the separation process, is provided.

Abstract: The present invention provides a lyocell raw cord prepared from at least 2-ply lyocell multifilaments, which gives a stress-strain curve exhibiting that (a) the lyocell raw cord has an elongation of 1.5% or less at an initial stress of 1.0 g/d, and an initial modulus value of 50 to 100 g/d; (b) has an elongation of 7% or less in a stress region of 1.0 g/d to 4.0 g/d; and (c) has an elongation of 1% or more at a tensile strength of 4.0 g/d to the breaking point, as measured in the dried state. The lyocell raw cord prepared according to the present invention can be used as industrial fibers, in particular, fibers for tire cords.

Abstract: A method for separating and purifying 2,6-dimethylnaphthalene, is provided in which 2,6-dimethylnaphthalene of high purity is obtained from a mixture of dimethylnaphthalene isomers with a high yield, by means of a combined process of column melt crystallization and sweating operation.

Abstract: The present invention provides a lyocell dipped cord prepared by dipping a lyocell raw cord comprising at least 2-ply lyocell multifilament in a dipping solution and curing the dipped cord, which gives a stress-strain curve exhibiting that (a) the lyocell dipped cord has an elongation of 1.2% or less at an initial stress of 1.0 g/d, and an initial modulus value of 80 to 200 g/d; (b) has an elongation of 6% or less in a stress region of 1.0 g/d to 4.0 g/d; and (c) has an elongation of 1% or more at a tensile strength of 4.0 g/d to the breaking point, as measured in the dried state. The lyocell dipped cord prepared according to the present invention can be used as industrial fibers, in particular, fibers for tire cords.

Abstract: A polyethylene terephthalate monofilament obtained by spinning a polyethylene terephthalate chip having an intrinsic viscosity of 0.8 to 1.3, which gives a stress-strain curve exhibiting an elongation of less than 2.5% at an initial stress of 2.0 g/d, with an initial modulus value of 80 to 160 g/d, an elongation of 7.5% or less in a stress range of from 2.0 g/d to 9.0 g/d, and an elongation of at least 2.0% or more in a stress range of from 10.0 g/d to the point of break, is provided.

Abstract: Disclosed is a 3-D crimp polyethylene terephthalate multifilament (BCF) having a stress-strain curve that (a) it elongates less than 5.0% when subjected to an initial stress of 1.0 g/d, (b) it has an initial modulus of 20 to 60 g/d, (c) it elongates at least 20% when subjected to a stress region of 1.0 to 2.5 g/d and (d) it elongates from a tensile strength of at least 3.0 g/d to the tensile strength at break. The BCF has improved physical properties such as excellent flame retardancy, high toughness, improved crimp uniformity and improved compressive elasticity modulus.

Abstract: The present invention relates to cellulose fiber containing 500 to 2000 of filaments and having homogeneous physical properties and the multi-filaments according to the present invention is characterized in that the strength and the breaking elongation of the multi-filaments are 4 to 9 g/d and 4 to 15%, respectively. In particular, the present invention is characterized in that each mono-filament selected 100 strands from every three part divided from multi-filaments has properties as following: (a) 3 to 9 g/d in average strength, 7 to 15% in average breaking elongation and 0.035 to 0.055 in by birefringence, (b) the differences of the above three parts are below 1.0 g/d in average strength, 1.5% in breaking elongation and 0.7 denier in denier, (c) the CV (%)(coefficient of variation) of the above three parts are below 10%, and (d) the birefringence differences of the above three parts are below 0.004.

Abstract: The present invention relates to a method for preparing 1,5-dimethyltetralin using a dealuminated zeolite beta catalyst. The preparation method of 1,5-dimethyltetralin according to the present invention has the effects of not only showing high conversion and high selectivity of 1,5-dimethyltetralin but also of suppressing deactivation of a zeolite beta catalyst so as to enhance the catalyst life, by using the dealuminated zeolite beta catalyst.

Abstract: Disclosed is a process for the manufacture of an elastic polyurethane fiber, including mixing one component selected from among polystyrene polymers or polystyrene copolymers having a number average molecular weight of 50,000–500,000 with polyurethane having a number average molecular weight of 15,000–100,000, to prepare a polymer mixture, which is then spun. The polyurethane elastic fiber made by the method is also provided, which is greatly increased in heat set properties, with a very low rate of change of fundamental properties as the results compared with conventional elastic polyurethane fibers. Hence, the elastic polyurethane fiber can be directly applied for preparation of end products requiring superior heat set properties with no change of conventional conditions of the process.

Abstract: There is provided with a cellulose fiber suitable for industrial material which is produced by a process comprising following steps: producing NMMO solution made in a manner to dissolve 0.1 wt % to 10 wt % of salt and polyvinyl alcohol in concentrated N-Methyl Morpholine N-oxide (NMMO) in liquid state; producing cellulose solution in a manner that said NMMO solution is mixed with cellulose powder and then said cellulose powder is swelled to produce cellulose solution; obtaining multifilament by solidifying said cellulose solution reached at a coagulation bath through air layer after extruded-sprayed with spraying nozzle having orifices of 500 to 2000; and winding said multifilament for storing after in turn washing, drying and treating with organic solvent, and the cellulose fiber according to the present invention is suitable for industrial materials due to excellent mechanical strength.

Abstract: The present invention relates to a polyethylene terephthalate nanocomposite fiber with enhanced modulus, and specifically to a technique for preparing a PET nanocomposite fiber with excellent initial and high-temperature modulus, which comprises adding 1 to 4% by weight of a compound selected from the group consisting of C56H122O12Si7, C31H71NO12Si8n, C59H127NO12Si8, and C33H76N2O12Si8, each of which is an organic/inorganic hybrid nanocompound, based on the total weight of the polymers, to prepare a polyethylene terephthalate nanocomposite chip having 85 mol % or more of the ethylene terephthalate units and an intrinsic viscosity in the range of 0.50 to 1.20, and then melt-spinning and stretching the composite chip.

Abstract: The present invention discloses a superconducting wire transposition method and superconducting transformer whose winding is formed of superconducting wire to enable the formation of transpositions. The superconducting wire transposition method characterized of different winding start positions of at least two disks wound with a plurality of parallel superconductive wires, and usage of different superconducting wires for conductors to be connected between the disks, thereby forming transpositions outside of the disks. Preferably, part of the plurality of disks are rotatably assembled in pairs so as to form transpositions while maintaining a total number of windings equally. Therefore, according to the present invention, transpositions can be formed without bending or welding superconducting wires and thus, deteriorations in superconductivity can be prevented.

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: It is an object of the present invention to provide a hybrid dip cord consisting of rayon yarn and lyocell yarn to apply to the carcass ply or cap ply (belt reinforced layer) of pneumatic radial tire used in a car and a radial tire using the same. And also, according to the present invent the hybrid dip cord and the radial tire for application to the carcass ply or cap ply (belt reinforced layer) of pneumatic radial tire used in cars are produced by means of the following steps; imparting S direction twist of 20 to 200 TPM yarn number to one rayon yarn to produce a pre-yarn, imparting twist to said one rayon pre-yarn and one non-twisted lyocell respectively to produce a ply twist yarn, and imparting cable twist to two ply of ply twist yarn made from combination of said ply twist yarn or impart cable twist to a ply twist yarn to be produced by regulating low the twist number of one lyocell yarn and the rayon yarn to one lyocell as 20 to 200 TPM when the ply twist processes.

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.