The present disclosure relates to electromagnetic shielding paper based on modification of a conductive MOF material and a preparation method thereof, and belongs to the technical field of electromagnetic shielding. The method includes the following steps: putting polyimide fibers into a precursor solution of the conductive MOF material, and reacting to obtain MOF material modified PI fibers; mixing the modified fibers with aramid pulp, and carrying out papermaking, squeezing and drying to obtain a paper-based precursor; generating a conductive polymer (polypyrrole) in situ by using a gas-phase polymerization method, and finally obtaining the electromagnetic shielding paper based on the modification of the conductive MOF material. The electromagnetic shielding paper prepared by the present disclosure not only has good conductivity and electromagnetic shielding performance, but also has good mechanical properties and thermal stability.

The present disclosure relates to electromagnetic shielding paper based on modification of a conductive MOF material and a preparation method thereof, and belongs to the technical field of electromagnetic shielding. The method includes the following steps: putting polyimide fibers into a precursor solution of the conductive MOF material, and reacting to obtain MOF material modified PI fibers; mixing the modified fibers with aramid pulp, and carrying out papermaking, squeezing and drying to obtain a paper-based precursor; generating a conductive polymer (polypyrrole) in situ by using a gas-phase polymerization method, and finally obtaining the electromagnetic shielding paper based on the modification of the conductive MOF material. The electromagnetic shielding paper prepared by the present disclosure not only has good conductivity and electromagnetic shielding performance, but also has good mechanical properties and thermal stability.

An aramid paper suitable for use as electrical insulation comprising a first outer layer and a second outer layer, each of which comprising 70 to 30 weight percent aramid floc and 30 to 70 weight percent aramid fibrids, and each of which being free of mica and having a first face and a second face; an inner layer comprising 50 to 70 weight percent aramid material and 30 to 50 weight percent mica and having a first face and a second face; wherein the first face of the first outer layer is a first outer face of the aramid paper, and the second face of the first outer layer is coextensive with and bound face-to-face with the first face of the inner layer solely by fibrids in the first outer layer and the inner layer; and wherein the first face of the second outer layer is coextensive with and bound face-to-face with the second face of the inner layer solely by fibrids in the second outer layer and the inner layer, and the second face of the second outer layer is a second outer face of the aramid paper; the aramid paper having a total of 25 to 40 weight percent mica.

An aramid paper suitable for use as electrical insulation comprising a first outer layer and a second outer layer, each of which comprising 70 to 30 weight percent aramid floc and 30 to 70 weight percent aramid fibrids, and each of which being free of mica and having a first face and a second face; an inner layer comprising 50 to 70 weight percent aramid material and 30 to 50 weight percent mica and having a first face and a second face; wherein the first face of the first outer layer is a first outer face of the aramid paper, and the second face of the first outer layer is coextensive with and bound face-to-face with the first face of the inner layer solely by fibrids in the first outer layer and the inner layer; and wherein the first face of the second outer layer is coextensive with and bound face-to-face with the second face of the inner layer solely by fibrids in the second outer layer and the inner layer, and the second face of the second outer layer is a second outer face of the aramid paper; the aramid paper having a total of 25 to 40 weight percent mica.

Paper with a grammage of 10-100 g/m.sup.2 including at least 20 wt. % of microfilaments and at least 20 wt. % of a non-resinous binder, the microfilaments having an average filament length in the range of 2-25 mm and titer less than 1.3 dtex, the non-resinous binder comprising at least one of fibrid or pulp. The paper shows high strength and other attractive properties.

Paper with a grammage of 10-100 g/m.sup.2 including at least 20 wt. % of microfilaments and at least 20 wt. % of a non-resinous binder, the microfilaments having an average filament length in the range of 2-25 mm and titer less than 1.3 dtex, the non-resinous binder comprising at least one of fibrid or pulp. The paper shows high strength and other attractive properties.

The present invention provides aramid compound paper with a pinning effect and a preparation method for the aramid compound paper. The preparation method for the aramid compound paper includes the following steps: preparing aramid paper from polyphenylene sulfide meltblown superfine fibers and aramid chopped fibers with wet papermaking; then placing polyphenylene sulfide meltblown superfine fiber non-woven fabrics on two sides of aramid base paper as face layers respectively; embedding the polyphenylene sulfide superfine fibers on the face layers into pores of the aramid paper at a middle layer by using a hot-pressing technology to be fusion-joined to the polyphenylene sulfide super-short fibers which are uniformly dispersed in the aramid base paper, so as to form the pinning effect; and meanwhile, melting and then solidifying the polyphenylene sulfide superfine fibers between the aramid chopped fibers to form a continuous network, and firmly bonding the aramid chopped fibers.

The present invention provides aramid compound paper with a pinning effect and a preparation method for the aramid compound paper. The preparation method for the aramid compound paper includes the following steps: preparing aramid paper from polyphenylene sulfide meltblown superfine fibers and aramid chopped fibers with wet papermaking; then placing polyphenylene sulfide meltblown superfine fiber non-woven fabrics on two sides of aramid base paper as face layers respectively; embedding the polyphenylene sulfide superfine fibers on the face layers into pores of the aramid paper at a middle layer by using a hot-pressing technology to be fusion-joined to the polyphenylene sulfide super-short fibers which are uniformly dispersed in the aramid base paper, so as to form the pinning effect; and meanwhile, melting and then solidifying the polyphenylene sulfide superfine fibers between the aramid chopped fibers to form a continuous network, and firmly bonding the aramid chopped fibers.

A nanofiber nonwoven product is disclosed which comprises a polyamide with a relative viscosity from 2 to 330, spun into nanofibers with an average diameter of less than 1000 nanometers (1 micron). In general, the inventive products are prepared by: (a) providing a polyamide composition, wherein the polyamide has a relative viscosity from 2 to 330; (b) melt spinning the polyamide composition into a plurality of nanofibers having an average fiber diameter of less than 1 micron, followed by (c) forming the nanofibers into the product.

A method for producing a wet-running friction paper includes providing a fiber portion with a fiber, providing a filler portion with a filler, providing a binder portion with a phenol-resin-based binder, dissolving the binder portion to form a phenolate, and processing the fiber portion, the filler portion and the phenolate in a paper production process to form the wet-running friction paper.