Abstract: There are provided a photo-cross-linking copolymerized hyaluronic acid sponge and a preparation method therefor, the sponge not being sticky and not dripping, having flexibility to be usable in various parts of the body, having excellent water binding force to help tissue regeneration, having very excellent biocompatibility so as to be absorbable into the skin when attached to the body for a long time, so that the trouble of having to be removed can be decreased, and comprising, through a photo-cross-linking reaction, polymers having various lengths so as to be applicable in various forms of medical antihemorrhagic agents, wound-coating agents, adhesive barriers.

Abstract: A printed circuit board and a method for manufacturing the same are provided. A printed circuit board according to an example includes a core formed by laminating dielectric substance layers; a capacitor including an internal electrode layer formed between the dielectric substance layers which are adjacent with each other and a connection via alternately connecting the internal electrode layers which are adjacent with each other to provide an electric charge having a different polarity to the internal electrode layers which are adjacent with each other and formed on the core; and a through via passing through the core.

Abstract: A multiblock copolymer includes a polysulfone repeating unit, a sulfonated polysulfone repeating unit, a polydialkylsiloxane repeating unit and an ethylenic unsaturated group at a terminal of the multiblock copolymer. Also provided are a method of preparing the multiblock copolymer, a polymer electrolyte membrane prepared from the multiblock copolymer, a method of preparing the polymer electrolyte membrane, and a fuel cell including the polymer electrolyte membrane. The polymer electrolyte membrane that has a high ionic conductivity and good mechanical properties and minimizes crossover of methanol can be manufactured at low cost. In addition, the structure of the multiblock copolymer can be varied to increase selectivity to a solvent used in a polymer electrolyte membrane.

Abstract: A multiblock copolymer includes a polysulfone repeating unit, a sulfonated polysulfone repeating unit and an ethylenic unsaturated group at a terminal of the multiblock copolymer. Also provided are a method of preparing the multiblock copolymer, a polymer electrolyte membrane prepared from the multiblock copolymer, a method of preparing the polymer electrolyte membrane, and a fuel cell including the polymer electrolyte membrane. The polymer electrolyte membrane that has a high ionic conductivity and good mechanical properties and minimizes crossover of methanol can be manufactured at low cost. In addition, the structure of the multiblock copolymer can be varied to increase selectivity to a solvent used in a polymer electrolyte membrane.

Abstract: A multiblock copolymer includes a polysulfone repeating unit of formula (1) below; a sulfonated polysulfone repeating unit of formula (2) below; and a polydialkylsiloxane repeating unit of formula (3) below, a method of preparing the multiblock copolymer, a polymer electrolyte membrane prepared from the multiblock copolymer, a method of preparing the polymer electrolyte membrane, and a fuel cell including the polymer electrolyte membrane: where l, m, and n are integers of 1-200; each of R1 through R8 is independently hydrogen, fluorine, or a C1-C10 alkyl group that can be substituted by at least one fluorine atom; and X represents a tetraalkylamine cation that can be substituted by hydrogen ions or other cations by ion exchange. The multiblock copolymer has a high ionic conductivity, high hydrophobicity, and good mechanical properties, can minimize crossover of methanol, and can be manufactured at a low cost.

Abstract: A multiblock copolymer includes a polysulfone repeating unit of formula (1) below; a sulfonated polysulfone repeating unit of formula (2) below; and an ethylenic unsaturated group at a terminal of the multiblock copolymer: where l and m are integers of 1-200; each of R1 through R4 is independently hydrogen, fluorine, or a C1-C10 alkyl group that is unsubstituted or substituted by at least one fluorine atom; and X represents a tetraalkylamine cation. Provided are a method of preparing the multiblock copolymer, a polymer electrolyte membrane prepared from the multiblock copolymer, a method of preparing the polymer electrolyte membrane, and a fuel cell including the polymer electrolyte membrane. The polymer electrolyte membrane that has a high ionic conductivity and good mechanical properties and minimizes crossover of methanol can be manufactured at a low cost. In addition, the structure of the multiblock copolymer can be varied to increase selectivity to a solvent used in a polymer electrolyte membrane.