US 12,438,231 B2
Meta-aramid polymer with grid structure, and preparation method therefor and use thereof
Zhenhong Guan, Yantai (CN); Ming Jiang, Yantai (CN); Dan Li, Yantai (CN); and Xiquan Song, Yantai (CN)
Assigned to YANTAI TAYHO ADVANCED MATERIALS RESEARCH INSTITUTE CO., LTD, Yantai (CN); and TAYHO BATTERY MATERIALS TECHNOLOGY CO., LTD, Yantai (CN)
Filed by YANTAI TAYHO ADVANCED MATERIALS RESEARCH INSTITUTE CO., LTD, Yantai (CN); and TAYHO BATTERY MATERIALS TECHNOLOGY CO., LTD, Yantai (CN)
Filed on Dec. 26, 2024, as Appl. No. 19/002,082.
Application 19/002,082 is a continuation of application No. PCT/CN2023/096447, filed on May 26, 2023.
Claims priority of application No. 202310152199.9 (CN), filed on Feb. 23, 2023.
Prior Publication US 2025/0158225 A1, May 15, 2025
Int. Cl. C09D 7/65 (2018.01); C08G 69/28 (2006.01); C08G 69/32 (2006.01); C09D 7/20 (2018.01); C09D 7/61 (2018.01); C09D 177/06 (2006.01); H01M 50/406 (2021.01); H01M 50/423 (2021.01)
CPC H01M 50/423 (2021.01) [C08G 69/28 (2013.01); C08G 69/32 (2013.01); C09D 7/20 (2018.01); C09D 7/61 (2018.01); C09D 7/65 (2018.01); C09D 177/06 (2013.01); H01M 50/406 (2021.01)] 3 Claims
 
1. A meta-aramid polymer with a grid structure whose structural formula is as follows:

OG Complex Work Unit Chemistry
wherein m, n, x and y represent polymerization degrees; each of R1 and R2 is alkyl groups with 3-5 carbon atoms; and
wherein the meta-aramid polymer is prepared from a method comprising the following steps:
(1) polycondensation: preparing a meta-aramid polymer by using solution polymerization including dissolving m-phenylenediamine (MPD) in an organic solvent, then adding isophthaloyl chloride (IPC) into a solution in 4 stages for polycondensation, independently 1st polycondensation stage, 2nd polycondensation stage, 3rd polycondensation stage and 4th polycondensation stage, adding an alkylating agent and a metal halide in the 1st and 2nd polycondensation stages, and controlling a reaction temperature, a stirring speed, reaction time and a system viscosity of each stage so as to obtain a prepared polymer solution comprising a polymer molecular structure with a grid structure; and
(2) washing: washing the prepared polymer solution in an aqueous solvent, and removing an oligomer and a metal salt in the polymer by water washing for 3 times so as to obtain the meta-aramid polymer with the grid structure; when the m-phenylenediamine (MPD) is dissolved in the organic solvent, the solution is kept at 0-10° C., the isophthaloyl chloride (IPC) is divided into 4 equal parts by weight and added into a system in the 4 stages for the polycondensation, the polycondensation in the 4 stages is defined as polycondensation 1, polycondensation 2, polycondensation 3 and polycondensation 4 respectively; the reaction temperature of the polycondensation 1 is 5-10° C., the stirring speed is 500-1,000 r/min, the alkylating agent and the metal halide are added, the reaction time is 30-60 min, a neutralizing agent is added, a reaction byproduct is removed, and the system viscosity is 100-300 mPa·s after the polycondensation 1 is completed; the reaction temperature of the polycondensation 2 is 10-30° C., the stirring speed is 500-700 r/min, the alkylating agent is added again, the reaction time is 30-45 min, the neutralizing agent is added, a reaction byproduct of this stage is removed, and the system viscosity is 500-1,000 mPa·s after the polycondensation 2 is completed; the reaction temperature of the polycondensation 3 is 25-45° C., the stirring speed is 200-350 r/min, the reaction time is 15-20 min, and the system viscosity is 2,000-3,000 mPa·s after the polycondensation 3 is completed; and the reaction temperature of the polycondensation 4 is 40-55° C., the stirring speed is 80-200 r/min, the reaction time is 10-30 min, and the system viscosity is 100,000-150,000 mPa·s after the polycondensation 4 is completed; the alkylating agent is chloro or bromo alkylolefin; and the metal halide is one of AlCl3, FeCl3, SbCl5 and SnCl4.