Abstract: The present invention relates to a polyamic acid composition and a method for preparing same. A polyimide using the polyamic acid composition according to the present invention has excellent dielectric breakdown voltage performance and corona discharge initiation voltage while maintaining heat resistance or mechanical strength, and a polyimide coating manufactured using the polyamic acid composition according to the present invention has excellent voltage endurance characteristics.

Abstract: Provided is polyimide varnish comprising: polyamic acid containing dianhydride monomer and diamine monomer as polymerized units; and nanosilica, wherein the nanosilica has an absolute value of zeta potential of 10.0 mV to 40.0 mV.

Abstract: Provided is polyimide varnish comprising: a polyamic acid solution containing diamine monomer and dianhydride monomer as polymerized units; a first additive containing boron nitride; a second additive containing nanosilica; and a dispersant.

Abstract: The present invention provides: a polyimide coating material, which has low dielectric properties and improved adhesion between a conductor and the coating material and flexibility of the coating material while simultaneously preventing dielectric breakdown and partial discharge; and a coated electric wire.

Abstract: The present invention relates to a polyimide powder and a preparation method therefor. With respect to the polyimide powder and the preparation method therefor, according to the present invention, a preparation process is simplified such that process efficiency can be improved, a polyimide is prepared in the form of a powder so as to facilitate molding thereof, and the polyimide has a low precipitation temperature and a high intrinsic viscosity so as to facilitate processing thereof, and has a uniform particle size so as to have excellent processability.

Abstract: The present invention relates to a polyamic acid composition for packaging electronic components and a method for packaging electronic components using the same, wherein the polyamic acid composition comprises a dianhydride main component having a benzophenone structure as a dianhydride-based monomer in a high proportion and a diamine component having a benzene ring as a diamine-based monomer, whereby it is possible to improve a coefficient of thermal expansion, a glass transition temperature, an elongation, and the like of a polyimide thin film formed therefrom, and when the polyimide thin film is used as a packaging material for an inorganic material such as a silicon water, it exhibits excellent adhesion to the inorganic material and can be easily removed upon O2 plasma removal, as well as has a remarkably low residual ratio of organic residues on the surface of the inorganic material after the removal, so that it can be easily used as a packaging material for electronic components and the like.

Abstract: The present invention relates to a polyamic acid composition for coating a conductor, and provides a polyamic acid composition for coating a conductor that prevents dielectric breakdown and partial discharge of a cured product while improving adhesion between a conductor and a coating material and flexibility of the coating material.

Abstract: The present application provides; a varnish, which is a polyimide precursor that is imidized by thermal curing, and implements the insulation, adhesion, heat resistance, mechanical strength, and light resistance of polyimide; a film including same; and a vehicle device coated with the film.

Abstract: Provided is a polyimide molded product comprising polyimide powder obtained by imidizing a dianhydride monomer and a diamine monomer, in which a bidirectional coefficient of thermal expansion (CTEBi-direction) according to Equation 1 below in the range of 25° C. to 300° C. is 0.7 to 1.5: Bidirectinal ? coefficient ? of ? thermal ? expansion ? ( CTE Bi - direction ) = Transverse ? coefficient ? of ? thermal ? expansion ? ( CTE x ) / Longitudinal ? coefficient ? of ? thermal ? expansion ? ( CTE y ) = C ? T ? E x / CTE y .

Abstract: The present application relates to a polyamic acid composition, a binder resin composition for an electrode, an electrode active material composition comprising the binder resin composition, and an electrode comprising same, and provides a novel binder material which has excellent mechanical strength and excellent binding force by synthesizing polyamic acid and applying same as a silicone-based negative electrode binder.

Abstract: The present application provides a polyimide powder in which a conductive filler is uniformly dispersed within particles, and a polyamic acid varnish that is prepared from the powder and capable of implementing a polyimide molded article that not only has excellent moldability and processability, but also has excellent conductivity, tensile strength, elongation, and elastic modulus.

Abstract: The present invention relates to a method for producing a polyimide powder, particularly to a method for producing a polyimide powder, which includes a) preparing a dispersion by dispersing a dianhydride and a diamine in distilled water; and b) introducing the dispersion of step a) into a reactor and conducting the reaction at a stirring speed of 300 rpm or more under temperature and pressure conditions. In the present invention, it is possible to improve physical properties and control the particle size and dispersibility without additional processes by using water-based polymerization and controlling the stirring speed in the production process.

Abstract: The present invention is a polyimide varnish for conductor coating, which provides a polyimide varnish comprising: a polyamic acid solution prepared through polymerization of at least one dianhydride monomer and at least one diamine monomer in an organic solvent; an aromatic carboxylic acid having four or more carboxyl groups; an alkoxy silane coupling agent; and an antioxidant, wherein the polyimide varnish has a solid content of 15 to 38 wt % on the basis of the total weight thereof, and a viscosity at 23° C. of 500 to 9,000 cP, and the coated material prepared from the polyimide varnish has a degree of softening resistance of 520° C. or higher, and a breakdown voltage (BDV) of 8 kV/mm or higher.

Abstract: The present application relates to a polyamic acid composition and a polyimide comprising same, and provides a polyamic acid composition which has a high concentration of polyamic acid solids and a low viscosity and, after hardening, has superior electrical properties as well as superior heat resistance, dimensional stability, and mechanical properties, and a polyimide and a polyimide film produced therefrom.

Abstract: A strut provided in an exhaust diffuser and having an airfoil-shaped cross-section is provided. The strut may include a cut portion configured to be formed in a trailing edge in a span direction. The cut portion is configured to provide a stepped portion in at least a portion of the trailing edge.

Abstract: The present application relates to a polyamic acid composition and a polyimide comprising same, and provides a polyamic acid composition which has a high concentration of polyamic acid solids and a low viscosity and, after hardening, has superior heat resistance, dimensional stability, and mechanical properties, and a polyimide and a polyimide film produced therefrom.

Abstract: The present application relates to a polyamic add composition and a polyimide comprising same, and provides a polyamic add composition which has a high concentration of polyamic acid solids and a low viscosity and, after hardening, has superior electrical properties as well as superior heat resistance, dimensional stability, and mechanical properties, and a polyimide and a polyimide film produced therefrom.

Abstract: The present application relates to a polyamic acid composition and a polyimide comprising same, and provides a polyamic acid composition which has a high concentration of polyamic acid solids and a low viscosity and, after hardening, has superior heat resistance, dimensional stability, and mechanical properties, and a polyimide and a polyimide film produced therefrom.

Abstract: The present application relates to a polyamic acid composition and a polyimide comprising same, and provides a polyamic acid composition which has a high concentration of polyamic acid solids and a low viscosity and, after hardening, has superior heat resistance, dimensional stability, and mechanical properties, and a polyimide and a polyimide film produced therefrom.

Abstract: A strut provided in an exhaust diffuser and having an airfoil-shaped cross-section is provided. The strut may include a cut portion configured to be formed in a trailing edge in a span direction. The cut portion is configured to provide a stepped portion in at least a portion of the trailing edge.