Abstract: The present invention provides polyester and a method for preparing same, the polyester including a repeating unit derived from dihydroxyalkyl tetrahydrofuran obtained from biomass; and a repeating unit derived from short-branched aliphatic dicarboxylic acid. Thus, the polyester has a carbon reduction effect and may be utilized as a novel biomass polyethylene terephthalate (PET) for packaging, by having excellent transparency, impact resistance, flexibility and elastic modulus compared to conventional PET.

Abstract: Provided is a heterogeneous catalyst for preparing a dicarboxylic acid aromatic heterocyclic compound, the heterogeneous catalyst including an active metal; and a basic metal oxide carrier capable of carrying the active metal and forming a complex by coordinate bonding with the dicarboxylic acid aromatic heterocyclic compound.

Abstract: The present invention relates to a method for preparing 1,3-cyclopentanediol by adding a ruthenium catalyst, from which the surface oxide layer is removed, to 4-hydroxy-2-cyclopentenone. The method is simple since 1,3-cyclopentanediol can be prepared in a single step through the use of the catalyst, without forming 3-hydroxycyclopentanone, which is a reaction intermediate, and moreover, the method can not only shorten a reaction time, but can also improve a yield of 1,3-cyclopentanediol.

Abstract: The present invention relates to a polyester or polyurethane polymer comprising a biomass-derived 1,3-cyclopentanediol monomer, and a method for preparing same.

Abstract: In the present invention, a water-based wetting dispersant having an acid value of 5 mg KOH/g or more and an amine value of 10 mg KOH/g or less is used to dilute and disperse black carbon and a hydrophobic fluorine resin in an organic solvent to manufacture a slurry for microporous layer formation. In this regard, the added amount of the water-based wetting dispersant is adjusted to 5 to 30 parts by weight on the basis of 100 parts by weight of black carbon. In the present invention, the slurry is applied to at least one surface of carbon fiber paper and dried to form a microporous layer in which two independent peaks appear as analyzed on a particle size graph, followed by compression and deposition thereof to fabricate a gas diffusion layer including the microporous layer in which two independent peaks appear as analyzed on a particle size graph.

Abstract: A method for producing a roll-type gas diffusion layer is disclosed. The method includes preparing a carbon paper from carbon fiber chops having a low modulus of 10 to 100 Gpa; impregnating the prepared carbon paper with a phenol resin, and then carbonizing the resin-impregnated carbon paper at 1,800 to 2,400° C.; forming a microporous polytetrafluoroethylene resin layer on one side of the carbonized carbon paper, to prepare a gas diffusion layer sheet; and winding the prepared gas diffusion layer sheet on a roll. Since the roll of gas diffusion layer is formed using the carbon fiber chops having a low modulus, the gas diffusion layer exhibits excellent and uniform spreading properties. Therefore, sealing between the gas diffusion layer and the fuel cell separation plate is reliably secured without using a separate binder.

Abstract: Disclosed is a method for producing roll-type gas diffusion layer. The method includes steps of preparing a carbon paper by using carbon fiber chops having a low modulus of 10 to 100 Gpa; impregnating the prepared carbon paper with a phenol resin or the like, and then carbonizing the same at 1,800 to 2,400° C.; forming a microporous polytetrafluoroethylene resin layer on one of both sides of the carbonized carbon paper, thus to prepare a sheet-like gas diffusion layer; and then, winding the prepared sheet-like gas diffusion layer on a roll.