This application provides a benzoxazine resin and a preparation method thereof, and an adhesive. The benzoxazine resin is represented by the following formula:

##STR00001##

where R.sub.1, R.sub.2, R.sub.3 and R.sub.4 are each independently selected from the group consisting of H, alkyl, alkoxy, cycloalkyl, and aryl, and at least one of R.sub.1, R.sub.2, R.sub.3 and R.sub.4 is H; X.sub.1 is an alkyl or/and alkoxy containing a long chain structure in main chain or side chain; X.sub.2 is one or more selected from alkyl, ether group, alkoxy, alkyl ester group, carbonyl, sulfone group, and thioether group; and n is 1-150.

A preparation method of a zeolite/polyimide composite membrane includes: synthesizing a zeolite-doped polyamic acid precursor casting solution by condensation polymerization synthesis; coating a substrate with the obtained casting solution, and obtaining a zeolite/polyamic acid composite porous membrane by non-solvent induced phase separation; and obtaining the zeolite/polyimide composite membrane by performing thermal imidization on the zeolite/polyamic acid composite porous membrane through gradient heating.

A polyimide composition includes a polyimide precursor or a polyimide that includes structural units derived from a first monomer including a diamine-based compound and structural units derived from a second monomer including a cardo group-containing dianhydride-based compound. The cardo group-containing dianhydride-based compound is included in a range from 12 mol % to 20 mol % based on a total number of moles of the second monomer.

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.

The disclosure provides a thermosetting polyimide resin and a manufacturing method thereof, a composition, a prepolymer, a film, an adhesive, and a use thereof. The composition includes at least: (a) a maleimide compound and (b) the thermosetting polyimide resin. The disclosure provides the thermosetting polyimide resin and the prepolymer, for manufacturing a film, an adhesive sheet, a cover film, a redistribution layer, a build-up board, a prepreg sheet, a high-frequency substrate, an integrated circuits carrier board, an adhesive for copper foil, a semiconductor packaging material, a radome, a substrate for server, a substrate for base station, a substrate for vehicle, etc.

The purpose of the present invention is to provide: a film having high thermal stability, high bending strength (tensile elongation), small retardation in the thickness direction, a low coefficient of thermal expansion, and high transparency; and a polyamic acid or varnish for obtaining the film. The film satisfies all of requirements (i)-(vi) below. (i) The average value of the coefficient of thermal expansion in the range of 100-200? C. is 35 ppm/K or less. (ii) The absolute value of the retardation in the thickness direction is 200 nm or less per 10 ?m of thickness. (iii) The glass transition temperature is 340? C. or higher. (iv) The total light transmittance is at least 85%. (v) The b* value in the L*a*b* color system is 5 or less. (vi) The tensile elongation is at least 10%.

Problem: The invention provides a polyimide precursor as well as a resin composition thereof that is excellent in coating properties of slit coating as well as productivity and also excellent in optical properties that are required for applications of flexible substrates.

Solution: The polyimide precursor comprises a structure unit derived from a fluorene backbone and a silicon-containing structure unit, and a weight-average molecular weight of the polyimide precursor is 90,000 to 250,000.

An object of the present invention is to provide a curable composition which has excellent patterning properties and makes it possible to obtain a cured film having excellent light blocking properties. Another object of the present invention is to provide a cured film, a light blocking film, a solid-state imaging element, and a solid-state imaging device. The curable composition contains inorganic particles, a polymerizable compound, and a polymerization initiator, in which the inorganic particles contain metal carbide-containing particles containing a carbide of an element in group 5 of the periodic table, and a content of the metal carbide-containing particles in a total mass of the inorganic particles is equal to or greater than 55% by mass.

A poly(siloxane-etherimide) composition comprising, based on the total weight of the composition, 70 to 90 wt % of a poly(siloxane-etherimide); and an additive comprising a polyester, a filler, or a combination thereof; wherein the filler comprises talc, calcium carbonate, or a combination comprising at least one of the foregoing; and wherein the composition has a number of drops to tracking at 250 volts of greater than or equal to 50 drops determined according to ASTM D-3638-85.

The present disclosure relates to a polyimide-based copolymer and a polyimide-based film including the same. The polyimide-based copolymer according to the present disclosure can provide a polyimide-based film exhibiting low absorbency while having excellent heat resistance and mechanical properties.