Abstract:
PURPOSE: A water-dispersive emulsion coating agent composition for a disposable food container is provided, to improve water/oil fastness, gloss and storage stability and to obtain no toxicity, no taste and no smell. CONSTITUTION: The composition comprises 100 parts by weight of a monomer comprising 60-80 wt% of a hydrophobic acryl-based monomer having a glass transition temperature higher than a room temperature and 20-40 wt% of a hydrophobic acryl-based monomer having a glass transition temperature lower than a room temperature; 0.1-5 parts by weight of an ionic monomer selected from carboxylic acid derivatives and sulfonic acid derivatives; and 0.2-5 parts by weight of a sugar-based surfactant. Preferably the composition is an emulsion containing a copolymer having a glass transition temperature of 20-60 deg.C and a number average molecular weight of 30,000-70,000, and the particle of the emulsion has a size of 50-400 nm.
Abstract:
PURPOSE: Provided is a method for recovering iodine from nitrogen compound solution using ion exchange resin. CONSTITUTION: The method comprises the steps of (a) passing nitrogen compound solution through a column filled with weak basic anion exchange resin, (b) recovering the anion exchange resin by passing 0.1-2N basic aqueous solution through the column at a temperature of 40-90°C, and (c) oxidizing the solution passing out the column at the step (b) by feeding persulfate-based oxidizing agent, wherein the nitrogen compound is selected from a group consisted of N-methyl-2-pyrrolidinone, N,N-dimethylformamide, pyridine, pyrrolidine and pyrrolidinone.
Abstract:
PURPOSE: A continuous polytetrafluoroethylene(PTFE) pyrolysis apparatus and a method for preparing PTFE using the apparatus are provided, to obtain tetrafluoroethylene of high purity massively with low cost. CONSTITUTION: The apparatus comprises at least two PTFE main tanks(10) which stores PTFE powder or particle and can be operated alternatively; a PTFE auxiliary tank(11) which is connected with the main PTFE main tanks(10) through a ball valve(24) and a transparent hose(12) for vacuum and stores PTFE supplied from the main tanks(10) temporarily before PTFE is applied to the process; a vertical-type screw feeder(13) which is operated by a motor and a magnetic driver, whose rotation number can be controlled, and which injects the PTFE supplied from the auxiliary tank(11) into a pyrolysis reactor through a cooler(15); and a vertical-type pyrolysis reactor(14) which pyrolyzes the PTFE supplied from the screw feeder(13) to generate tetrafluoroethylene gas and delivers the generated tetrafluoroethylene gas to a tetrafluoroethylene condensation tank.
Abstract:
PURPOSE: Provided is a production method of hydrophobic glass having improved transparency, durability and weather resistance compared with conventional glass by coating surface modifier on glass through sol-gel process. CONSTITUTION: The hydrophobic glass is produced by coating glass with surface modifier through sol-gel process. The surface modifier is prepared by mixing a reactive copolymer containing perfluoro group and hydrolyzed metal alkoxide in a weight ratio of 0.01-100 : 1. The hydrolyzed metal alkoxide is obtained by hydrolyzing metal alkoxide and alcohol in a weight ratio of 0.01-100 : 1 in the presence of an acid catalyst, wherein the metal alkoxide is at least one compound selected from tetramethoxy silane, tetraethoxy silane, (2-perfluoro octyl)ethyl trimethoxy silane, etc. The reactive copolymer is obtained by polymerizing main monomer, C2-C20 acrylate or methacrylate containing perfluoro group, and a comonomer containing at least one of poly-unsaturated double bond in a weight ratio of 0.01-100 : 1, wherein the comonomer is selected from vinyl chloride, benzyl (meth) acrylate, vinyl acetate, styrene, N-methylol acrylamide, acrylate, etc.
Abstract:
PURPOSE: Provided is a water repellent glass coating which has excellent water repellency and durability, and is easily dissolved in solvent, and which can retain its transparency when coated on glass surface. CONSTITUTION: The coating further comprises 0.01-10.0 wt% of oligomeric copolymer containing perfluoro radical and silicon radical, which is obtained by copolymerizing an acrylate or methacrylate containing C4-C12 perfluoroalkyl radical as a main monomer, with an acrylate or methacrylate compound containing silicon radical as a comonomer, with respect to the coating. The reaction ratio of main monomer: comonomer is 5-95:95-5(by weight). The acrylate or methacrylate containing C4-C12 perfluoroalkyl radical is selected from perfluoroalkylethyl acrylate or perfluoroalkylmethyl methacrylate.
Abstract:
PURPOSE: A method for preparing a polymer microemulsion containing a perfluoroalkyl group is provided, to reduce the particle size of the microemulsion by employing a surfactant together with perfluoroalkyl alcohol for improving the permeating power into a substrate, thereby enhancing the water repelling property, the oil repelling property and the pollution resistance. CONSTITUTION: The method comprises the step of emulsion polymerizing a compound containing a perfluoroalkyl group, a monomer containing an unsaturated double bond and a surfactant, wherein the surfactant is a mixture of a surfactant selected from the group consisting of nonionic. anionic and cationic surfactants and a perfluoroalkyl alcohol. Preferably the perfluoroalkyl alcohol is represented by the formula 1 or 2(formula 1: CnF2n+1SO2N(R1)CH2CH2OH, formula 2: CnF2n+1CH2CH2OH), wherein R1 is methyl group or ethyl group; and n is an integer of 3-21. The content of the surfactant is 5-15 wt% based on the weight of the monomer, and the content of the perfluoroalkyl alcohol is 2-30 wt% of based on the weight of the surfactant.
Abstract:
PURPOSE: A continuous polytetrafluoroethylene(PTFE) pyrolysis apparatus and a method for preparing PTFE using the apparatus are provided, to obtain tetrafluoroethylene of high purity massively with low cost. CONSTITUTION: The apparatus comprises at least two PTFE main tanks(10) which stores PTFE powder or particle and can be operated alternatively; a PTFE auxiliary tank(11) which is connected with the main PTFE main tanks(10) through a ball valve(24) and a transparent hose(12) for vacuum and stores PTFE supplied from the main tanks(10) temporarily before PTFE is applied to the process; a vertical-type screw feeder(13) which is operated by a motor and a magnetic driver, whose rotation number can be controlled, and which injects the PTFE supplied from the auxiliary tank(11) into a pyrolysis reactor through a cooler(15); and a vertical-type pyrolysis reactor(14) which pyrolyzes the PTFE supplied from the screw feeder(13) to generate tetrafluoroethylene gas and delivers the generated tetrafluoroethylene gas to a tetrafluoroethylene condensation tank.
Abstract:
PURPOSE: A continuous preparation of perfluoroethyliodide denoted by C2F5I is accomplished under activate liquid catalyst. The compound is used in a variety of water/oil repellent process or contaminant-resistant agents and high performance surfactant. CONSTITUTION: A continuous preparation of perfluoroethyliodide is performed by using iodide, pentafluoroiodide, tetrafluoroethylene(TFE) and reaction catalyst. The preparation comprises further continuously introducing TFE under room pressure and in the presence of antimony pentafluoride (SbF5) reaction catalyst in liquid state to produce perfluoroethyliodide product. The iodide and iodide pentafluoride is admixed together in a reaction molar ratio (I2/IF5) of 0.02-5 and the reaction catalyst SbF5 is dissolved under stirring at room temperature to 50 deg.C.