Disclosed is a method for precipitating a polymer by adding a precipitation agent into a first suspension to form a second suspension; wherein the first suspension comprises a polymer and an aqueous solvent; and wherein the polymer comprises a copolymer comprising a structural unit derived from an acid group-containing monomer and a structural unit derived from a hydrophobic group-containing monomer. The method for precipitation of a polymer disclosed herein is developed to initiate the bond disruption and/or breakage between the polymer and the aqueous solvent within the second suspension. This is accompanied with the structural transformation of the polymer driven by the intermolecular and intramolecular interactions of the polymer chains which brings about the precipitation of the polymer. The method circumvents both complex separation process and contamination of the polymer, enables excellent materials recovery and allows the precipitation of the polymer to be achieved within a short time frame. An application of the method for precipitating a polymeric binder in a battery electrode is disclosed herein.

Provided is a method for delaminating a composite by immersing the composite into a delamination solution; wherein the composite comprises a substrate and a coating applied on one side or both sides of the substrate comprising a polymeric binder; and wherein the polymeric binder comprises a copolymer comprising a structural unit derived from an acid group-containing monomer. The use of weak acid-containing delamination solution allows for complete delamination of the composite in a highly efficient manner. Furthermore, the delamination method disclosed herein circumvents complex separation process, contamination and corrosion of substrate and enables an excellent materials recovery. An application of the method for delaminating an electrode for a battery is also disclosed.

Provided is a method for delaminating a composite by immersing the composite into a delamination solution; wherein the composite comprises a substrate and a coating applied on one side or both sides of the substrate comprising a polymeric binder; and wherein the polymeric binder comprises a copolymer comprising a structural unit derived from an acid group-containing monomer. The use of weak acid-containing delamination solution allows for complete delamination of the composite in a highly efficient manner. Furthermore, the delamination method disclosed herein circumvents complex separation process, contamination and corrosion of substrate and enables an excellent materials recovery. An application of the method for delaminating an electrode for a battery is also disclosed.

A method of separating a polyisoolefin elastomer from non-polymeric components in an organic solvent involves ultrafiltration of a solution of the polyisoolefin elastomer and non-polymeric components in an organic solvent through a semipermeable membrane to substantially retain the polyisoolefin elastomer in a retentate and provide the non-polymeric components in a permeate. Advantageously, stabilizers for the polyisoolefin elastomer are retained in the retentate along with the polyisoolefin elastomer, permeate flux through the membrane is higher as concentration of the polyisoolefin elastomer in the solution increases up to a concentration limit, the separated polyisoolefin elastomer in the retentate has a molecular weight that can be substantially unchanged even when ultrafiltration is conducted at elevated temperature and the amount of polyisoolefin elastomer in the permeate is unmeasurable providing an oligomer-rich permeate uncontaminated by polyisoolefin elastomer. A process for curing a polyisoolefin copolymer involves reducing content of an oligomer to 900 ppm or less in a mixture of the oligomer and the polyisoolefin copolymer to produce an oligomer-depleted mixture, and adding a resin cure system to the oligomer-depleted mixture to cure the polyisoolefin copolymer.

A method of separating a polyisoolefin elastomer from non-polymeric components in an organic solvent involves ultrafiltration of a solution of the polyisoolefin elastomer and non-polymeric components in an organic solvent through a semipermeable membrane to substantially retain the polyisoolefin elastomer in a retentate and provide the non-polymeric components in a permeate. Advantageously, stabilizers for the polyisoolefin elastomer are retained in the retentate along with the polyisoolefin elastomer, permeate flux through the membrane is higher as concentration of the polyisoolefin elastomer in the solution increases up to a concentration limit, the separated polyisoolefin elastomer in the retentate has a molecular weight that can be substantially unchanged even when ultrafiltration is conducted at elevated temperature and the amount of polyisoolefin elastomer in the permeate is unmeasurable providing an oligomer-rich permeate uncontaminated by polyisoolefin elastomer. A process for curing a polyisoolefin copolymer involves reducing content of an oligomer to 900 ppm or less in a mixture of the oligomer and the polyisoolefin copolymer to produce an oligomer-depleted mixture, and adding a resin cure system to the oligomer-depleted mixture to cure the polyisoolefin copolymer.

To provide a method capable of producing fluorinated polymer particles in which formation of fine particles or formation of large aggregates is sufficiently suppressed even in the case of a fluorinated polymer having high solubility in a solvent.

The method comprises the following steps (i) and (ii), being a method for producing particles of a fluorinated polymer (A) which has either one or both of structural units (u1) derived from tetrafluoroethylene and structural units (u2) having no sulfonic acid type functional group and having a cyclic structure and fluorine atoms, and which has structural units (u3) having a sulfonic acid type functional group, wherein the proportion of the structural units (u1) is from 0 to 82 mol % in all structural units (100 mol %) in the fluorinated polymer (A): (i) a step of preparing solution or dispersion of the fluorinated polymer (A) having the above fluorinated polymer (A) dissolved or dispersed in a solvent (B), wherein the following conditions (i-1) and (i-2) are satisfied: (i-1) the solvent (B) contains a good solvent (B2) wherein the solubility of the fluorinated polymer (A) is at least 30%, (i-2) even when the above solution or dispersion of the fluorinated polymer (A) is passed through a filter of 200 mesh made of stainless steel, no residue remains on the filter, (ii) a step of mixing the above solution or dispersion of the fluorinated polymer (A) and a solvent (C) to aggregate the fluorinated polymer (A) to form particles of the fluorinated polymer (A), wherein the following conditions (ii-1) to (ii-3) are satisfied: (ii-1) the solvent (C) contains a poor solvent (C1) whereby the degree of swelling of the fluorinated polymer (A) is at most 100%, (ii-2) the degree of swelling of the fluorinated polymer (A) by a mixed solvent (BC) of the solvent (B) and the solvent (C) is from 70 to 250%, (ii-3) the ratio of the mass (W.sub.C) of the solvent (C) to the mass (W.sub.B) of the solvent (B) is from 1 to 5.

To provide a method capable of producing fluorinated polymer particles in which formation of fine particles or formation of large aggregates is sufficiently suppressed even in the case of a fluorinated polymer having high solubility in a solvent.

The method comprises the following steps (i) and (ii), being a method for producing particles of a fluorinated polymer (A) which has either one or both of structural units (u1) derived from tetrafluoroethylene and structural units (u2) having no sulfonic acid type functional group and having a cyclic structure and fluorine atoms, and which has structural units (u3) having a sulfonic acid type functional group, wherein the proportion of the structural units (u1) is from 0 to 82 mol % in all structural units (100 mol %) in the fluorinated polymer (A): (i) a step of preparing solution or dispersion of the fluorinated polymer (A) having the above fluorinated polymer (A) dissolved or dispersed in a solvent (B), wherein the following conditions (i-1) and (i-2) are satisfied: (i-1) the solvent (B) contains a good solvent (B2) wherein the solubility of the fluorinated polymer (A) is at least 30%, (i-2) even when the above solution or dispersion of the fluorinated polymer (A) is passed through a filter of 200 mesh made of stainless steel, no residue remains on the filter, (ii) a step of mixing the above solution or dispersion of the fluorinated polymer (A) and a solvent (C) to aggregate the fluorinated polymer (A) to form particles of the fluorinated polymer (A), wherein the following conditions (ii-1) to (ii-3) are satisfied: (ii-1) the solvent (C) contains a poor solvent (C1) whereby the degree of swelling of the fluorinated polymer (A) is at most 100%, (ii-2) the degree of swelling of the fluorinated polymer (A) by a mixed solvent (BC) of the solvent (B) and the solvent (C) is from 70 to 250%, (ii-3) the ratio of the mass (W.sub.C) of the solvent (C) to the mass (W.sub.B) of the solvent (B) is from 1 to 5.

To provide a method capable of producing fluorinated polymer particles in which formation of fine particles or formation of large aggregates is sufficiently suppressed even in the case of a fluorinated polymer having high solubility in a solvent.

The method comprises the following steps (i) and (ii), being a method for producing particles of a fluorinated polymer (A) which has either one or both of structural units (u1) derived from tetrafluoroethylene and structural units (u2) having no sulfonic acid type functional group and having a cyclic structure and fluorine atoms, and which has structural units (u3) having a sulfonic acid type functional group, wherein the proportion of the structural units (u1) is from 0 to 82 mol % in all structural units (100 mol %) in the fluorinated polymer (A): (i) a step of preparing solution or dispersion of the fluorinated polymer (A) having the above fluorinated polymer (A) dissolved or dispersed in a solvent (B), wherein the following conditions (i-1) and (i-2) are satisfied: (i-1) the solvent (B) contains a good solvent (B2) wherein the solubility of the fluorinated polymer (A) is at least 30%, (i-2) even when the above solution or dispersion of the fluorinated polymer (A) is passed through a filter of 200 mesh made of stainless steel, no residue remains on the filter, (ii) a step of mixing the above solution or dispersion of the fluorinated polymer (A) and a solvent (C) to aggregate the fluorinated polymer (A) to form particles of the fluorinated polymer (A), wherein the following conditions (ii-1) to (ii-3) are satisfied: (ii-1) the solvent (C) contains a poor solvent (C1) whereby the degree of swelling of the fluorinated polymer (A) is at most 100%, (ii-2) the degree of swelling of the fluorinated polymer (A) by a mixed solvent (BC) of the solvent (B) and the solvent (C) is from 70 to 250%, (ii-3) the ratio of the mass (W.sub.C) of the solvent (C) to the mass (W.sub.B) of the solvent (B) is from 1 to 5.

Described herein are methods for continuous solution polymerization. The method may comprise polymerizing one or more monomers and comonomers in the presence of a solvent in a polymerization reactor to produce a polymer solution; determining the composition of the polymer solution exiting the polymerization reactor in an on-line fashion; determining at least one of the critical pressure or critical temperature; comparing the critical pressure and/or critical temperature to the actual temperature of the polymer solution and the actual pressure of the polymer solution; heating or cooling the polymer solution to a temperature within 50° C. of the critical temperature; and passing the polymer solution through a pressure letdown valve into a liquid-liquid separator, where the pressure of the polymer solution is reduced or raised to a pressure within 50 psig of the critical pressure to induce a separation of the polymer solution into two liquid phases.

Described herein are methods for continuous solution polymerization. The method may comprise polymerizing one or more monomers and comonomers in the presence of a solvent in a polymerization reactor to produce a polymer solution; determining the composition of the polymer solution exiting the polymerization reactor in an on-line fashion; determining at least one of the critical pressure or critical temperature; comparing the critical pressure and/or critical temperature to the actual temperature of the polymer solution and the actual pressure of the polymer solution; heating or cooling the polymer solution to a temperature within 50° C. of the critical temperature; and passing the polymer solution through a pressure letdown valve into a liquid-liquid separator, where the pressure of the polymer solution is reduced or raised to a pressure within 50 psig of the critical pressure to induce a separation of the polymer solution into two liquid phases.