Abstract: The present invention relates to a method for preparing polyarylene sulfide, in which the polyarylene sulfide is prepared by a polymerization reaction of reactants including a diiodo aromatic compound and a sulfur compound, the method including: further adding 0.01 to 10.0 wt. % of diphenyl disulfide with respect to the weight of the polyarylene sulfide to the reactants to form the polyarylene sulfide having a melting point of 265 to 320° C. The diphenyl disulfide included in the reactants according to the present invention costs far less than other conventional polymerization inhibitors to dramatically lower the production cost, and the polyarylene sulfide prepared using the diphenyl disulfide exhibits low iodine content and very excellence in thermal stability.

Abstract: The present invention relates to a method of prepairing a heat-resistant polyamide by carrying out condensation polymerization with a monomer mixture including a diester compound and a diamine compound. The present invention provides an economical method of prepairing a heat-resistant polyamide in that a monomer, a raw material, is simply and chiefly prepared, and the polymerizing reaction time is short because it does not need solvent separately.

Abstract: A method for preparing polyarylene sulfide having reduced iodine content and excellent thermal stability is described. The method includes reacting a composition comprising diiodide aromatic compounds, sulfur compounds, and a polymerization terminator. The preparation method may effectively reduce iodine content of polyarylene sulfide to prevent corrosion of post processing equipment, improve properties of polyarylene sulfide such as thermal stability, and the like, and thus, it may be usefully applied in the industrial field relating to preparation of polyarylene sulfide.

Abstract: The present invention relates to a process for preparing iodinated aromatic compounds. Particularly, the present invention comprises the step of performing the iodination of a non-halogenated aromatic compound, a monoiodo aromatic compound, a diiodo aromatic compound, and iodine in the presence of a zeolite catalyst under oxygen atmosphere. In the process for preparing iodinated aromatic compounds according to the present invention, an iodination and an iodine conversion simultaneously occur, and then prevent side-reactions. Also, the lifetime of an iodination catalyst used therein can be extended by controlling the reaction temperature stably. Therefore, the process can be used for mass production of diiodo compound.

Abstract: A polyester/polycarbonate blend having superior thermal stability and superior color stability is disclosed. The polyester/polycarbonate blend comprises: (a) P(ET-CT) (poly(ethylene terephthalate-co-1,4-cyclohexylene dimethylene terephthalate) which is copolymerized with 1,4-cyclohexanedimethanol (CHDM) of 40 to 90 mol % with respect to total diol components; (b) polyethylene terephthalate (PET); (c) polycarbonate (PC); and (d) germanium of 1 to 100 ppm (weight ratio) with respect to total polyester/polycarbonate blend, wherein with respect to total polyester/polycarbonate blend, the amount of the P(ET-CT) and PET is 50 to 90 weight %, the amount of the PET is 1 to 6 times in weight ratio with respect to the P(ET-CT), and the amount of the PC is 10 to 50 weight %.

Abstract: The present invention relates to polyarylene sulfide, in which a ratio of a peak area of a polymer chain of a second polyarylene sulfide having a lower molecular weight than the maximum peak molecular weight to a peak area of a polymer chain of a first polyarylene sulfide having a higher molecular weight than the maximum peak molecular weight is 1.3 or less in the molecular weight distribution of the polyarylene sulfide, as measured by gel permeation chromatography using polystyrene as a standard, and a preparation method thereof. This polyarylene sulfide exhibits excellent processability and generates no burrs (flashes) or the like, and can satisfactorily mold a product requiring high molding precision.

Abstract: This disclosure relates to polyarylene sulfide that may exhibit and maintain excellent properties and a method for preparing the same, wherein the polyarylene sulfide is in the form of pellet of 2 to 10 mm size immediately after melt polymerization, and has residual solvent content of 300 ppm or less, based on the total weight of resin. The polyarylene sulfide may exhibit and maintain excellent properties, particularly it does not generate foam in the product or stain on the surface, has excellent mechanical properties such as tensile strength, and the like, and thus, it may be usefully applied in the industrial field of preparing polyarylene sulfide and manufacturing a molded product using the same.

Abstract: This disclosure relates to polyarylene sulfide that may exhibit excellent processability at low temperature, decrease outgassing and flash or burr generation, and thus may satisfactorily mold a product requiring high molding accuracy, and a method for preparing the same. Specifically, the polyarylene sulfide includes an arylene sulfide repeat unit and an arylene disulfide repeat unit, wherein the weight ratio of the arylene sulfide repeat unit:arylene disulfide repeat unit is 1:0.0001 to 1:0.05.

Abstract: This disclosure relates to a method for preparing polyarylene sulfide having reduced iodine content while having excellent thermal stability, specifically to a method comprising polymerization reacting a composition comprising diiodide aromatic compounds, sulfur compounds, and a polymerization terminator. The preparation method may effectively reduce iodine content of polyarylene sulfide to prevent corrosion of post processing equipment, improve properties of polyarylene sulfide such as thermal stability, and the like, and thus, it may be usefully applied in the industrial field relating to preparation of polyarylene sulfide.

Abstract: The present invention relates to a method of preparing iodinated aromatic compounds, and more preferably a method of preparing iodinated aromatic compounds comprising a step of iodinating a react ant including an aromatic compound, a di-iodo aromatic compound or water, and iodine (I2) in the presence of a zeolite catalyst and oxygen. The method of the present invention has an advantage that by iodination of a reactant including the aromatic compound, and the di˜ iodo aromatic compound or water in the presence of the zeolite catalyst and oxygen, the temperature of the iodinating reactor can be controlled reliably and constantly, thereby resulting in improved productivity per unit weight of catalyst and inhibition of a side reaction in accordance with suppression of producing impurities.

Abstract: A polyester resin copolymerized with isosorbide and 1,4-cyclohexane dimethanol and having an improved impact strength, and a method for preparing the same are disclosed. The copolymerized polyester resin has an alternating structure of acid moieties which are derived from acid components and diol moieties which are derived from diol components, wherein the acid components comprise terephthalic acid, and the diol components comprise (i) 5˜99 mol % of 1,4-cyclohexanedimethanol and (ii) 1˜60 mol % of isosorbide with respect to the total diol components.

Abstract: The present invention relates to a cation-exchanged zeolite catalyst for an transiodination and a process for producing mono-iodo benzene by using it. Particularly, the cation-exchanged zeolite catalyst has a molar ratio of Si/Al from 5 to 100 and is ion-exchanged with an alkali metal or an alkaline earth metal in range of 2% to 50% of ion exchange capacity. Further, the process for producing mono-iodo benzene of the present invention comprises the step of performing a transiodination by using the cation-exchanged zeolite catalyst to produce mono-iodo benzene from reactants including benzene and one or more multi-iodo benzenes selected from the group consisting of di-iodo benzene and tri-iodo benzene.

Abstract: The present invention relates to a method of prepairing a heat-resistant polyamide by carrying out condensation polymerisation with a monomer mixture including a diester compound and a diamine compound. The present invention provides an economical method of prepairing a heat-resistant polyamide in that a monomer, a raw material, is simply and chiefly prepared, and the polymerizing reaction time is short because it does not need solvent separately.

Abstract: The present invention relates to a high-strength inflammable blend resin composition including a polyphenylene sulfide resin and a polyethylene terephthalate resin. More specifically, the resin composition of the present invention includes: a basic blend resin containing 10 to 80 wt. % of a polyphenylene sulfide resin, and 20 to 90 wt. % of a polyethylene terephthalate resin; and 0.1 to 20 parts by weight of a modified polystyrene or a styrene-based elastomer with respect to 100 parts by weight of the basic blend resin.

Abstract: The present invention relates to a method for preparing polyarylene sulfide with a reduced free iodine content. More specifically, the method for preparing polyarylene sulfide includes: (a) polymerizing reactants including a diiodo aromatic compound and a sulfur compound to form a polyarylene sulfide; and (b) maintaining the polyarylene sulfide product at 100 to 260° C. for heat-setting. The preparation method of the present invention effectively reduces the free iodine content of the polyarylene sulfide to prevent potential corrosion of facilities for the subsequent process and improves the properties of the polyarylene sulfide product such as thermal stability, so the method can be usefully applied to industrial fields in regard to the preparation of polyarylene sulfide.

Abstract: The present invention relates to a method for preparing polyarylene sulfide, in which the polyarylene sulfide is prepared by a polymerization reaction of reactants including a diiodo aromatic compound and a sulfur compound, the method including: further adding 0.01 to 10.0 wt. % of diphenyl disulfide with respect to the weight of the polyarylene sulfide to the reactants to form the polyarylene sulfide having a melting point of 265 to 320° C. The diphenyl disulfide included in the reactants according to the present invention costs far less than other conventional polymerization inhibitors to dramatically lower the production cost, and the polyarylene sulfide prepared using the diphenyl disulfide exhibits low iodine content and very excellence in thermal stability.

Abstract: The present invention relates to a process for preparing iodinated aromatic compounds. Particularly, the present invention comprises the step of performing the iodination of a non-halogenated aromatic compound, a monoiodo aromatic compound, a diiodo aromatic compound, and iodine in the presence of a zeolite catalyst under oxygen atmosphere. In the process for preparing iodinated aromatic compounds according to the present invention, an iodination and an iodine conversion simultaneously occur, and then prevent side-reactions. Also, the lifetime of an iodination catalyst used therein can be extended by controlling the reaction temperature stably. Therefore, the process can be used for mass production of diiodo compound.

Abstract: A method for preparing fatty acid alkyl ester for bio-diesel fuel is disclosed, wherein fatty acid, specifically fatty acid distillate reacts with alcohol. The method does not require the glycerin purification process, and has the superior conversion ratio of fatty acid. The method for preparing fatty acid alkyl ester for bio-diesel fuel comprises the step of carrying out a counter current type esterification reaction of fatty acid and alcohol in each tray of a counter current column reactor at a temperature of 200 to 350 and a pressure of 1 to 35 bar. Here the raw material of the fatty acid is fed to an upper part of the counter current column reactor and the alcohol is fed to a lower part of the counter current column reactor. The counter current column reactor has a number of trays which are installed horizontally to have a number of vertical compartments. Each of the number of trays has an opening part at one end thereof to communicate one compartment with an adjoining compartment.

Abstract: A method and an apparatus for preparing fatty acid alkyl ester for bio-diesels are disclosed, wherein fatty acid, specifically fatty acid distillate reacts with alcohol, without a catalyst. The method does not require the purification process of the catalyst and glycerin, and has the superior conversion ratio of fatty acid. The method for preparing fatty acid alkyl ester for bio-diesel fuels comprises the step of esterifying fatty acid raw material with alcohol, under a temperature of 200 to 350° C. and a pressure of atmospheric pressure to 10 bar. The apparatus for preparing fatty acid alkyl ester for bio-diesel fuels, comprises: the first reactor for esterifying fatty acid raw material with alcohol under a temperature of 200° C. to 350° C. and a pressure of atmospheric pressure to 10 bar and for converting 80 to 90% of total fatty acid into fatty acid alkyl ester; and the second reactor for converting remaining fatty acid unconverted at the first reactor into fatty acid alkyl ester.

Abstract: A polyester/polycarbonate blend having superior transparency and heat resistance which is useful for producing transparent polyester articles is disclosed. The blend of polyester and polycarbonate includes (a) polyethyleneterephthalate (PET) prepared with terephthalic acid component and ethylene glycol component, or copolymerized polyethyleneterephthalate prepared with terephthalic acid component and ethylene glycol component, and further copolymerized with 1 to 10 mol % of isophthalic acid, cyclohexane dimethanol (CHDM), di-ethylene glycol and/or alkylene glycol of 3 to 6 carbon atoms component with respect to acid or diol components; (b) polycarbonate (PC); and (c) CHDM modified PET prepared with 20 to 80 mol % CHDM with respect to diol components, wherein the amount of the PC is 10 to 60 wt % with respect to the mixture of (a) PET and (b) PC, and the amount of the (c) CHDM modified PET is 0.2 to 2.5 times by weight with respect to the amount of (b) PC.