Abstract: A graft copolymer and a preparation method and use thereof. The method for preparing a graft copolymer includes: dissolving an N-ethyl-2-pyrrolidinone-substituted flavan-3-ol (EPSF) and a starch in a polar organic solvent, to obtain a raw material solution; and mixing the raw material solution with ascorbic acid and hydrogen peroxide to obtain a mixture, and subjecting the mixture to a grafting reaction, to obtain the graft copolymer.

Abstract: A frictional false twister is disclosed. The twister has a plurality of rotating friction plates located between the nip of the front rollers and the yarn guide. The friction plates are staggeringly arranged for rubbing a twisted yarn. The spinning direction of the twisted yarn is opposite to the rotating direction of the friction plates. Through the action of the frictional false twister, the twist of the yarn between the false twisting device to the front nip can be increased, shortening the twisting triangle height, and increasing the spinning strength. As the yarn and the outer surface of the friction plate make relative sliding and rubbing, the friction damping force correspondingly reduces the spinning tension in the twisting triangle.

Abstract: A frictional false twister is disclosed. The twister has a plurality of rotating friction plates located between the nip of the front rollers and the yarn guide. The friction plates are staggeringly arranged for rubbing a twisted yarn. The spinning direction of the twisted yarn is opposite to the rotating direction of the friction plates. Through the action of the frictional false twister, the twist of the yarn between the false twisting device to the front nip can be increased, shortening the twisting triangle height, and increasing the spinning strength. As the yarn and the outer surface of the friction plate make relative sliding and rubbing, the friction damping force correspondingly reduces the spinning tension in the twisting triangle.