Abstract: The present invention provides a method for preparing a high-performance graphite sheet by imidizing a polyamic acid resulting from a reaction of dianhydride monomer(s) and diamine monomer(s) to obtain a polyimide film; and carbonizing and/or graphitizing the polyimide film to obtain a high-performance graphite sheet, where the polyimide film contains 2 or more fillers having different average particle diameters, and the thermal conductivity of the graphite sheet is at least 1,400 W/m·K. Further, the present invention provides a graphite sheet obtained by the above method.

Abstract: The present invention relates to a polyimide film and a preparation method thereof. According to the present invention, a polyamic acid solution having a high weight-average molecular weight may be obtained by adjusting viscosity and solid content of the polyamic acid solution, and thus, a desired polyimide film may be prepared therefrom. Furthermore, since a length of carbon chains rearranged during graphitization is increased, a graphite sheet having excellent thermal conductivity can be prepared from the polyimide film of the present invention. Also, since the polyimide film has improved windability by further including inorganic particles as a filler, it may facilitate the wind operation.

Abstract: The present invention provides a polyimide film for a roll type graphite sheet prepared by imidizing a polyamic acid formed by a reaction of a dianhydride monomer and a diamine monomer, where the polyimide film has a modulus of 2.7 GPa or more.

Abstract: The present invention provides a method for preparing a high-performance graphite sheet by imidizing a polyamic acid resulting from a reaction of dianhydride monomer(s) and diamine monomer(s) to obtain a polyimide film; and carbonizing and/or graphitizing the polyimide film to obtain a high-performance graphite sheet, where the polyimide film contains 2 or more fillers having different average particle diameters, and the thermal conductivity of the graphite sheet is at least 1,400 W/m·K. Further, the present invention provides a graphite sheet obtained by the above method.

Abstract: The present disclosure provides a polyimide film prepared from a precursor composition containing a polyamic acid and an organic solvent and having a value of (first FWHM?second FWHM)/(first FWHM+second FWHM) which is less than 0.4, a graphite sheet prepared from the polyimide film, and a method for preparing a graphite sheet.

Abstract: The present disclosure provides a polyimide film prepared from a precursor composition containing a polyamic acid and an organic solvent and having a value of (first FWHM?second FWHM)/(first FWHM+second FWHM) which is less than 0.4, a graphite sheet prepared from the polyimide film, and a method for preparing a graphite sheet.

Abstract: The present disclosure provides a polyimide film prepared from a precursor composition containing a polyamic acid and an organic solvent and having a value of (first FWHM?second FWHM)/(first FWHM+second FWHM) which is less than 0.4, a graphite sheet prepared from the polyimide film, and a method for preparing a graphite sheet.

Abstract: The present invention provides a method for preparing a high-performance graphite sheet by imidizing a polyamic acid resulting from a reaction of dianhydride monomer(s) and diamine monomer(s) to obtain a polyimide film; and carbonizing and/or graphitizing the polyimide film to obtain a high-performance graphite sheet, where the polyimide film contains 2 or more fillers having different average particle diameters, and the thermal conductivity of the graphite sheet is at least 1,400 W/m·K. Further, the present invention provides a graphite sheet obtained by the above method.

Abstract: The present invention relates to a polyimide film and a preparation method thereof. According to the present invention, a polyamic acid solution having a high weight-average molecular weight may be obtained by adjusting viscosity and solid content of the polyamic acid solution, and thus, a desired polyimide film may be prepared therefrom. Furthermore, since a length of carbon chains rearranged during graphitization is increased, a graphite sheet having excellent thermal conductivity can be prepared from the polyimide film of the present invention. Also, since the polyimide film has improved windability by further including inorganic particles as a filler, it may facilitate the wind operation.