Method for preparing pure chitosan fiber

A method for preparing a pure chitosan fiber, comprising the following steps:

• S1, preparing an acetic acid solution, wherein the acetic acid solution is prepared from water and acetic acid, with an acetic acid mass ratio of 1 w %-5 w %;
• S2, preparing a chitosan stock solution:
• adding a chitosan raw material into the acetic acid solution obtained in step S1 for preliminary dissolution, and then placing a chitosan spinning solution after preliminary dissolution in a pretreatment machine;
• S3, treating the chitosan spinning solution:
• starting the pretreatment machine, mixing the chitosan raw material with the acetic acid solution to form a mixture, and then separating, debubbling, and filtering the mixture to obtain the chitosan spinning solution;
• and
• S4, preparing a chitosan fiber:
• transporting the chitosan spinning solution obtained in step S3 to a spinning nozzle using a metering pump, immersing the chitosan spinning solution sprayed from the spinning nozzle in a coagulation bath for double diffusion, and solidifying the spinning solution to form a nascent fiber;
• removing a residual solution by stretching the nascent fiber;
• removing chemical reagents with deionized water from the stretched nascent fiber, and performing shearing and drying to obtain the chitosan fiber;
• wherein the pretreatment machine in step S3 comprises a body (1);
• a driving mechanism (2) is arranged in the body (1);
• a stirring mechanism (5) is arranged in the driving mechanism (2);
• a scraping mechanism (4) is arranged below the stirring mechanism (5);
• a preliminary treatment mechanism (3) is arranged at an inner upper side of the body (1);
• the driving mechanism (2) penetrates through the preliminary treatment mechanism (3) and is arranged in the body (1);
• a separation mechanism (6) is arranged on a bottom of the body (1);
• the body (1) comprises an outer drum (11);
• an inner drum (12) is arranged in the outer drum (11);
• separation holes (14) are symmetrically arranged in the inner drum (12);
• a guide slot (15) is formed in the inner drum (12);
• a baffle plate (13) is arranged outside the separation holes (14);
• a gap is arranged between the inner drum (12) and the outer drum (11);
• the baffle plate (13) is located between the inner drum (12) and the outer drum (11);
• the inner drum (12) is movably connected to the baffle plate (13);
• a base plate is arranged on a bottom of the inner drum (12) and a bottom of the outer drum (11);
• the baffle plate (13) is fixedly connected to the base plate;
• the inner drum (12) and the outer drum (11) are coaxially arranged;
• the driving mechanism (2) comprises a driving motor (22);
• the driving motor (22) is located on a top of the outer drum (11);
• an output end of the driving motor (22) is provided with a threaded rod (21);
• the threaded rod (21) and the inner drum (12) are coaxially arranged;
• the preliminary treatment mechanism (3) comprises an extrusion block (31);
• the extrusion block (31) is arranged in the inner drum (12), and the extrusion block (31) is movably connected to the inner drum (12);
• a first electric telescopic rod (37) is arranged on an inner side of the extrusion block (31);
• a matching block (32) is arranged at an end portion of the first electric telescopic rod (37);
• a second guide plate (36) is arranged below the matching block (32);
• a first guide plate (34) is arranged below the second guide plate (36);
• at least two layers of filter plates (33) are arranged between the first guide plate (34) and the second guide plate (36);
• each layer of filter plate (33) is spliced into a ring by several filter plates (33);
• a supporting block (35) is arranged on an inner side of each filter plate (33);
• the supporting block (35) is rotatably connected to the first guide plate (34);
• the filter plates (33) are rotatably connected to the first guide plate (34);
• the filter plates (33) are in contact with the second guide plate (36);
• the stirring mechanism (5) comprises a stirring rod (52);
• at least one filter hole (51) is formed in the stirring rod (52);
• the stirring rod (52) is designed in an arc shape, and an end portion of the stirring rod (52) abuts against an inner wall of the inner drum (12);
• a connecting sleeve (53) is arranged in the stirring rod (52);
• the connecting sleeve (53) is in threaded connection with a threaded rod (21);
• a second telescopic rod is arranged at an end portion of the stirring rod (52);
• a guide ball (55) is arranged at an end portion of the second telescopic rod;
• and a connecting rod (56) is arranged outside the second telescopic rod.