A monomer represented by Chemical Formula 1: ##STR00001##
wherein, in Chemical Formula 1, R.sup.1, R.sup.2, A.sup.1, A.sup.2, L.sup.1, L.sup.2, o, p, q, and r are the same as defined in the detailed description.

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.

A power storage device including a negative electrode active material layer which contains carbon particles, silicon-based particles and a polyimide-based binder, in which the negative electrode active material layer has a porosity of more than 40%. The power storage device has a high charge/discharge capacity and excellent cycle characteristics.

Provided are a hydrophilic polyamide and polyimide retaining characteristics particular to polyamides and polyimides, such as heat resistance. A polymeric compound is provided having a repeating unit represented by the following formula (1): ##STR00001##
wherein M.sup.1 and M.sup.2 each independently represent any one selected from the group consisting of a hydrogen atom, a monovalent metal atom, an alkaline earth metal atom and an ammonium ion, provided that M.sup.1 and M.sup.2 are not a hydrogen atom at the same time; X.sup.1 and X.sup.2 represent an organic group; m and n each independently represent the number of substituents; Z.sup.1 represents a hydrogen atom or an optionally substituted carbonyl group; Z.sup.2 represents an optionally substituted hydrocarbon group; Z.sup.3 represents a hydrogen atom or an optionally substituted carbonyl group; and when Z.sup.1 or Z.sup.3 is an optionally substituted carbonyl group, they optionally form a ring structure together with Z.sup.2, each independently.

Provided is a polyimide having a repeating unit represented by the following Formula (1):

##STR00001##

wherein R.sup.1 represents a tetravalent group; R.sup.2 represents a divalent group; provided that at least one of R.sup.1's is represented by the following Formula (2); and among R.sup.2's, at least one group is represented by the following Formula (3), and at least one other group is represented by the following Formula (4):

##STR00002##

Disclosed herein are a polyimide film for graphite sheets and a graphite sheet manufactured using the same. The polyimide film is fabricated by imidizing a precursor composition including: a polyamic acid prepared by reacting a dianhydride monomer with a diamine monomer; and an organic solvent, wherein the diamine monomer includes about 30 mol % to about 70 mol % of 4,4′-methylenedianiline and about 30 mol % to about 70 mol % of 4,4′-oxydianiline based on the total number of moles of the diamine monomer, 4,4′-methylenedianiline and 4,4′-oxydianiline being present in total in an amount of about 85 mol % or more based on the total number of moles of the diamine monomer.

Present invention is related to a polyimide of formula as following:

##STR00001##

and a ketone-containing alicyclic dianhydride of formula as following:

##STR00002##

wherein: R1, R2, R3, R4 denote hydrogen atom or carbon containing functional group with carbon number at a range of 1-4; R5 denotes diamine group; and n equals to any positive integer.

A resin composition includes a first prepolymer and a second prepolymer, the first prepolymer being prepared from a first mixture subjected to a prepolymerization reaction, the second prepolymer being prepared from a second mixture subjected to a prepolymerization reaction, wherein the first mixture includes a maleimide resin and a benzoxazine resin, and the second mixture includes a maleimide resin and a bis(trifluoromethyl)benzidine. The resin composition may be used to make various articles, such as a prepreg, a resin film, a laminate or a printed circuit board, and at least one of the following properties can be improved, including copper foil peeling strength, dissipation factor, ratio of thermal expansion, cure shrinkage and glass transition temperature.

The present invention provides a polyimide composite having a structural formula of PI/Fe.sub.3O.sub.4-(β-CD-Ada)x, wherein x=3-5. One aspect of the invention provides a polyimide composite. By introducing Fe.sub.3O.sub.4 as a host material of an electromagnetic wave absorption material and introducing a guest material, a repairing property of the material itself is imparted by an interaction between the host material and the guest material. Therefore, the polyimide composite has an electromagnetic radiation shielding property and a self-repairing property.

The present invention provides a random or block polyimide-siloxane copolymer, which may be prepared from a hard amine monomer, a dianhydride monomer, and a soft amine monomer, may have mechanical properties, flexibility, and thermal properties adjusted through the control of soft amine content, and may exhibits high thermal stability, corrosion resistance, transparency and flexibility, and a method for preparing the same. The random or block polyimide-siloxane copolymer, which may be flexible and thermally stable and may exhibits adjustable mechanical properties and skin-like sensory functions, may be applied to flexible electronic devices.