Methods for making sulfonated poly(phenylene ether) and articles made therefrom

A method for sulfonation of poly(phenylene ether), comprising:

• determining the desired sulfonation level;
• if the desired sulfonation level is greater than 20% then dissolving a poly(phenylene ether) comprising 2,6-dimethyl-1,4-phenylene ether units, 2,3,6-trimethyl-1,4-phenylene ether units, 3,3′,5,5′-tetramethyl-4,4′-dihydroxybiphenyl ether units, or a combination thereof, in 1,2-dichloroethane and a cosolvent to form a solvent mixture in a mixing vessel, wherein the cosolvent comprises methyl ethyl ketone, diethyl ether, methyl ethyl sulfone, ethyl acetate, tetramethylene sulfone, or a combination thereof;
• combining a sulfonating agent with the solvent mixture, wherein the sulfonating agent reacts with the poly(phenylene ether) to form sulfonated poly(phenylene ether);
• precipitating the sulfonated poly(phenylene ether);
• and
• filtering the precipitated sulfonated poly(phenylene ether) to form a sulfonated poly(phenylene ether) precipitate and a filtrate, and
• if the desired sulfonation level is less than or equal to 20% then dissolving poly(phenylene ether) in a solvent mixture comprising 1,2-dichloroethane and greater than 1 to 10 wt % of a cosolvent, wherein the weight percentages are based upon 100 wt % of the solvent mixture, to form a solvent mixture in a mixing vessel;
• then combining a sulfonating agent with the solvent mixture, wherein the sulfonating agent reacts with the poly(phenylene ether) to form sulfonated poly(phenylene ether);
• precipitating the sulfonated poly(phenylene ether);
• and filtering the precipitated sulfonated poly(phenylene ether) to form a sulfonated poly(phenylene ether) precipitate and a filtrate.

A method for sulfonation of poly(phenylene ether), comprising

• dissolving a poly(phenylene ether) comprising 2,6 dimethyl 1,4-phenylene ether units, 2,3,6 trimethyl-1,4-phenylene ether units, 3,3′,5,5′-tetramethyl-4,4′-dihydroxybiphenyl ether units, or a combination thereof, in 1,2-dichloroethane and optionally a cosolvent to form a solvent mixture in a mixing vessel;
• combining a sulfonating agent with the solvent mixture, wherein the sulfonating agent reacts with the poly(phenylene ether) to form sulfonated poly(phenylene ether);
• precipitating the sulfonated poly(phenylene ether);
• and
• filtering the precipitated sulfonated poly(phenylene ether) to form a sulfonated poly(phenylene ether) precipitate and a filtrate;
• wherein the sulfonated poly(phenylene ether) has a uniform sulfonation level of 20 to 50% as determined by NMR.

A method for sulfonation of poly(phenylene ether), comprising:

• determining a desired sulfonation level;
• if the desired sulfonation level is greater than 20% then dissolving a poly(phenylene ether) comprising 2,6 dimethyl 1,4-phenylene ether units, 2,3,6 trimethyl-1,4-phenylene ether units, 3,3′,5,5′-tetramethyl-4,4′-dihydroxybiphenyl ether units, or a combination thereof, in 1,2-dichloroethane and optionally a cosolvent to form a solvent mixture in a mixing vessel;
• combining a sulfonating agent with the solvent mixture, wherein the sulfonating agent reacts with the poly(phenylene ether) to form sulfonated poly(phenylene ether);
• precipitating the sulfonated poly(phenylene ether);
• and
• filtering the precipitated sulfonated poly(phenylene ether) to form a sulfonated poly(phenylene ether) precipitate and a filtrate, and
• if the desired sulfonation level is less than or equal to 20% then dissolving poly(phenylene ether) in 1,2-dichloroethane and optionally a cosolvent to form a solvent mixture in a mixing vessel;
• then combining a sulfonating agent with the solvent mixture, wherein the sulfonating agent reacts with the poly(phenylene ether) to form sulfonated poly(phenylene ether);
• precipitating the sulfonated poly(phenylene ether);
• and filtering the precipitated sulfonated poly(phenylene ether) to form a sulfonated poly(phenylene ether) precipitate and a filtrate;
• wherein the sulfonated poly(phenylene ether) has a uniform sulfonation level as determined by NMR.