Highly alkali-stable poly(arylene alkylene piperidinium) cationic polymer having branched structure, and preparation method and use thereof

Alkali-stable poly(arylene alkylene piperidinium) cationic polymers having branched structures, comprising:

• one or more of a central unit, a linear unit L1, and a linear unit L2;
• wherein the central unit comprises one or more of an MA unit, a piperidinium group (m-DMP), or and CA unit;
• wherein the linear unit L1 comprises a piperidinium group (m-DMP) and a BA unit;
• and
• wherein the linear unit L2 comprises a BA unit and a CA unit;
• wherein the piperidinium group (m-DMP) has a structural formula of
• wherein R1 and R2 are independently selected from hydrocarbyl groups having 1-20 carbon atoms, or wherein R1 and R2 are connected to each other to form a cycloalkyl group consisting of 4 to 7 carbon atoms, and wherein the counter ion A′ is selected from one or more of halide ions, a methyl sulfate ion, a hydroxide ion, or a bicarbonate ion;
• wherein the MA unit comprises 2 to 6 aromatic rings, and is independently selected from one or more of the following structures:
• wherein the BA unit is independently selected from one or more of the following structures:
• and wherein the CA unit comprises one or more of
• wherein R3 and R4 are independently selected from hydrocarbyl groups having 1-20 carbon atoms, or wherein R3 and R4 are connected to each other to form a cycloalkyl group consisting of 4 to 7 carbon atoms;
• wherein each R5 is independently selected from a hydrogen atom, a hydrocarbyl group having 1-20 carbon atoms, or a fully or partially fluorinated alkyl group having 1-6 carbon atoms;
• wherein k=0 or 1;
• x=0 to 12;
• wherein Q is selected from one or more of a hydrogen atom, —N+(R6)3, or nitrogen-containing heterocyclic cations;
• wherein each R6 is independently selected from a hydrocarbyl group having 1-20 carbon atoms in —N+(R6)3;
• and
• wherein the nitrogen-containing heterocyclic cation comprises one or more of partially or fully substituted pyrazolium, pyrrolidinium, piperidinium, imidazolium, or quinuclidinium groups with the following structures:
• wherein R61 to R610 are independently selected from hydrocarbyl groups having 1-20 carbon atoms, and the counter ion A is selected from one or more of halide ions, a methyl sulfate ion, a hydroxide ion, or a bicarbonate ion;
• wherein the central unit of the alkali-stable poly(arylene alkylene piperidinium) cationic polymers having branched structures is connected to the linear unit L1 of the alkali-stable poly(arylene alkylene piperidinium) cationic polymers having branched structures, and the central unit comprising the MA unit and the piperidinium group (m-DMP) has a structural formula shown as follows:
• or,
• wherein the linear unit L1 of the highly alkali-stable poly(arylene alkylene piperidinium) cationic polymers having branched structures is connected to the central unit and the linear unit L2 of the highly alkali-stable poly(arylene alkylene piperidinium) cationic polymers having branched structures, and wherein the central unit comprising the MA unit, the piperidinium group (m-DMP) and the CA unit has a structural formula shown as follows: