Embodiments in accordance with the present invention encompass polyamic acid or polyimide polymers containing a reactive maleimide end group as well as photosensitive compositions made therefrom which are useful for forming films that can be patterned to create structures for microelectronic devices, microelectronic packaging, microelectromechanical systems, optoelectronic devices and displays. In some embodiments the compositions of this invention are shown to feature excellent hitherto unachievable mechanical properties. The negative images formed therefrom exhibit improved thermo-mechanical properties, among other property enhancements.

The invention relates to new polyimide solutions having ecological and toxicological benefits compared to existing polyimide solutions as well as well as b their use, in particular for coating applications.

A transparent polyimide film, prepared from a copolymerized polyamide acid according to a chemical cyclization method, is provided. The copolymerized polyamide acid requires at least a semi-aromatic polyamide acid, and the semi-aromatic polyamide acid is formed by reacting cyclobutane-1,2,3,4-tetracarboxylic dianhydride (CBDA) and 2,2′-bis(trifluoromethyl)diaminodiphenyl (TFMB). The molar number of dianhydrides of the semi-aromatic polyamide acid is more than 20% of the total molar number of anhydrides of the copolymerized polyamide acid, so that the transparent polyimide film has a light transmittance greater than 80%, a chroma b* less than 5, and a CTE less than 35 ppm/° C.

Disclosed herein are a polyimide film for graphite sheets, a method of fabricating the same, and a graphite sheet fabricated using the same. The polyimide film is fabricated by imidizing a polyamic acid formed by reaction between a dianhydride monomer and a diamine monomer, wherein the reaction is carried out in the presence of a metal compound and the polyamic acid forms a chelate with metal ions.

Disclosed herein is a polyimide film that is obtained by imidizing a polyamic acid solution containing two or more dianhydride components selected from the group consisting of 3,3′,4,4′-benzophenonetetracarboxylic dianhydride (BTDA), 3,3′,4,4′-biphenyltetracarboxylic dianhydride (BPDA), and pyromellitic dianhydride (PMDA), and a diamine component including m-tolidine and p-phenylenediamine (PPD) and has a glass transition temperature (Tg) of 320° C. or higher, a moisture absorption rate of 0.4% or less, and a dielectric dissipation factor (Df) of 0.004 or less.

Disclosed herein are a polyimide film for graphite sheets, a method of fabricating the same, and a graphite sheet fabricated using the same. The polyimide film is fabricated by imidizing a polyamic acid formed by reaction between a dianhydride monomer and a diamine monomer, wherein the reaction is carried out in the presence of particles of a metal compound having an average particle diameter (D.sub.50) of about 1 μm to about 6 μm.

A polymer-dispersed liquid crystal composition, a preparation method of a polymer-dispersed liquid crystal film, and a display panel are provided. The polymer-dispersed liquid crystal composition includes a prepolymer and a liquid crystal molecule, wherein the prepolymer is a fluorine-containing polyimide precursor chemically bonded to a polyaniline, including a polycondensation unit formed from a fluorine-containing dianhydride monomer and a fluorine-containing diamine monomer. In the present application, the conductive polyaniline is chemically bonded to the fluorine-containing polyimide precursor to increase the conductivity of the polyimide precursor. Further, a polymer-dispersed liquid crystal film having a driving voltage lower than 30 V and excellent insulating property and radiation resistance is obtained.

One embodiment relates to a composition for forming a polyimide film for a cover window, a method for preparing the same, and uses thereof. According to one embodiment, it is possible to provide a polyimide film for a cover window that has excellent isotropy and scattering resistance, and at the same time is flexible and has excellent bending physical properties, without lowering colorless and transparent optical physical properties. In addition, the polyimide film for a cover window according to an embodiment may be usefully used in various flexible display devices.

A hybrid crosslinked polymeric membrane and a process for fabricating the same are provided. Specifically, the hybrid crosslinked polymer membrane comprises a glassy polymer and a ladder-structured polysilsesquioxane and has a crosslinked structure. The hybrid crosslinked polymer membrane can have an excellent permeability of carbon dioxide by virtue of an increase in the free volume and enhanced plasticization resistance, chemical resistance, and durability.

A method for producing polyimide microparticles may comprise: combining a diamine and a dianhydride in a first dry, high boiling point solvent; reacting the diamine and the dianhydride to produce a mixture comprising poly(amic acid) (PAA) and the first dry, high boiling point solvent; emulsifying the mixture in a matrix fluid that is immiscible with the first dry, high boiling point solvent using an emulsion stabilizer to form a precursor emulsion that is an oil-in-oil emulsion; and heating the precursor emulsion during and/or after formation to a temperature sufficient to polymerize the PAA to form the polyimide microparticles.