▎ 摘　　要

NOVELTY - Polymer binder comprises soft phase region and hard phase region. The hard phase area is obtained by polymerizing rigid monomer A, and soft phase area is obtained by polymerizing flexible monomer B and monomer C containing dynamic interaction groups. USE - Polymer binder is used in electrode sheet for lithium ion battery (claimed). ADVANTAGE - The polymer binder has high mechanical strength, excellent cohesiveness, good flexibility and self-healing ability, repairs the damage of the bonding network caused by the expansion of the silicon anode, improves the cycle performance of the silicon anode, endows the adhesive with good flexibility and self-repairing ability. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for the following: (1) a method for preparing polymer binder, which involves polymerizing rigid monomer A, flexible monomer B, and monomer C containing dynamic interaction groups to form self-healing adhesive that combining soft-hard phase regions, polymerizing rigid monomer A, adding flexible monomer B and monomer C containing dynamic interaction group to continue the polymerization, obtaining binder containing both hard phase region and soft phase region, polymerization method is living radical polymerization, RAFT reagent is selected from dibenzyl trithiocarbonate, 4-cyano-4-(((dodecylthio)thiocarbonyl)thio)pentanoic acid, 2-(dodecane thiocarbonylthio)-2-methylpropionic acid and cyanomethyl methyl(phenyl)aminodithioformate, molar ratio of the amount of the RAFT reagent to the total repeating unit is 0.01-5%; and (2) a electrode sheet for lithium ion batteries, which comprises polymer binder, lithium ion battery electrode sheet is positive electrode sheet and/or negative electrode sheet, lithium ion battery electrode sheet is negative electrode sheet; (3) a method for preparing lithium ion battery electrode sheet, which involves preparing polymer binder, electrode active material and/or conductive agent into slurry, coating and drying, using 0.1-20 wt.% binder; and (4) a lithium ion battery, which comprises lithium ion battery electrode sheet.