Sulfonated poly (phenylene ether) and method for making same

Abstract

The sulfonated poly (phenylene ether) comprises phenylene ether repeat units and has a degree of sulfonation of 20% to 50% and a molar ratio of sulfonyl chloride (-SO2Cl): sulfonic acid (-SO3H) of less than or equal to 0.06. The sulfonated poly (phenylene ether) may be used in membranes, such as for gas and ion exchange based separations. A process for producing sulfonated poly (phenylene ether) is also described.

Description

[0001] Related Applications

[0002] This application claims priority to and the benefit of European Patent Application No. 22178729.4 filed on June 13, 2022, the contents of which are incorporated herein by reference in their entirety. Background Art

[0003] Disclosed herein are sulfonated poly(phenylene ether)s and methods of making the same.

[0004] Poly(phenylene ether)s are commercially attractive materials due to their unique combination of physical, chemical, and electrical properties. In addition, combinations of poly(phenylene ether)s with other polymers or additives provide blends that result in improved overall properties, including chemical resistance, high strength, and high flow. Various sulfonated grades of poly(phenylene ether) materials are desired as new commercial applications are explored.

[0005] Conventional processes for sulfonating poly(phenylene ether)s develop heterogeneity with progressive levels of sulfonation, affecting the reaction system and making further sulfonation difficult.Sulfonation of poly(phenylene ether)s can also result in molecular weight degradation and in the presence of residual reaction byproducts.

[0006] It would be desirable to provide an improved process for sulfonating poly(phenylene ether) that can provide high sulfonation levels (e.g., up to 50%) and reduced sulfonyl chloride content. Retaining a high molecular weight polymer with a low oligomer content after sulfonation would be another advantage. Summary of the invention

[0007] Sulfonated poly(phenylene ether)s represent an aspect of the present disclosure. The sulfonated poly(phenylene ether)s comprise repeating units of the formula:

[0008]

[0009] A degree of sulfonation of 20% to 50% as determined by nuclear magnetic resonance spectroscopy; and a molar ratio of sulfonyl chloride (-SO2Cl):sulfonic acid (-SO3H) of less than or equal to 0.06; wherein, in the above formula, Z 1 is independently at each occurrence sulfonic acid, sulfonyl chloride, halogen, unsubstituted or substituted C 1-12 Hydrocarbyl (provided that the hydrocarbyl group is not a tertiary hydrocarbyl), C 1-12 Hydrocarbon thio group, C 1-12 Hydroxyl, or C 2-12 A haloalkyloxy group (wherein at least two carbon atoms separate the halogen and oxygen atoms); Z 2 is independently at each occurrence sulfonic acid, sulfonyl chloride, hydrogen, halogen, unsubstituted or substituted C 1-12 Hydrocarbyl (provided that the hydrocarbyl group is not a tertiary hydrocarbyl), C1-12 Hydrocarbon thio group, C 1-12 Hydroxyl, or C 2-12 halohydrocarbyloxy (wherein at least two carbon atoms separate the halogen and oxygen atoms); and x is 1 or 2.

[0010] Another aspect is a method of preparing a sulfonated poly(phenylene ether), the method comprising dissolving the poly(phenylene ether) in 1,2-dichloroethane to form a mixture; combining a sulfonating agent and a cosolvent, preferably ethyl acetate, with the mixture to form a sulfonated poly(phenylene ether), wherein nitrogen is passed through the mixture at a flow rate greater than or equal to 30 ml / min / mole of sulfonating agent; precipitating the sulfonated poly(phenylene ether); and isolating the precipitated sulfonated poly(phenylene ether).

[0011] Another aspect is a membrane comprising a sulfonated poly(phenylene ether).

[0012] Another aspect is a porous carbon precursor comprising a sulfonated poly(phenylene ether).

[0013] The above described and other features are exemplified by the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Reference is now made to the accompanying drawings, which are by way of illustration and not limitation.

[0015] Figure 1 is a schematic diagram of an embodiment of a process for sulfonating poly(phenylene ether). DETAILED DESCRIPTION

[0016] Methods have been developed to reliably sulfonate poly(phenylene ether)s to a degree of sulfonation in the range of 20% to 50%. Advantageously, the sulfonated poly(phenylene ether)s include low levels of sulfonyl chloride, and reduced amounts of oligomeric impurities. The sulfonated poly(phenylene ether)s can maintain a high molecular weight (e.g., a number average molecular weight greater than 60,000 g / mol), and a low (e.g., less than 1 weight percent) oligomer content. Sulfonated poly(phenylene ether)s with low sulfonyl chloride content can provide improved ion exchange capacity (IEC). The method is also scalable and allows the production of poly(phenylene ether)s with different levels of sulfonation. Homogeneous sulfonation is also possible.

[0017] Thus, one aspect of the present disclosure is a sulfonated poly(phenylene ether). The sulfonated poly(phenylene ether) comprises repeating units of the formula:

[0018]

[0019] Among them, in the above formula, Z 1 is independently at each occurrence sulfonic acid, sulfonyl chloride, halogen, unsubstituted or substituted C 1-12Hydrocarbyl (provided that the hydrocarbyl group is not a tertiary hydrocarbyl), C 1-12 Hydrocarbon thio group, C 1-12 Hydroxyl, or C 2-12 A haloalkyloxy group (wherein at least two carbon atoms separate the halogen and oxygen atoms); Z 2 is independently at each occurrence sulfonic acid, sulfonyl chloride, hydrogen, halogen, unsubstituted or substituted C 1-12 Hydrocarbyl (provided that the hydrocarbyl group is not a tertiary hydrocarbyl), C 1-12 Hydrocarbon thio group, C 1-12 Hydroxyl, or C 2-12 halohydrocarbyl (wherein at least two carbon atoms separate the halogen and oxygen atoms); and x is 1 or 2. As used herein, the term "hydrocarbyl", whether used alone or as a prefix, suffix or fragment of another term, refers to a residue containing only carbon and hydrogen. The residue can be aliphatic or aromatic, straight chain, cyclic, bicyclic, branched, saturated, or unsaturated. It can also contain a combination of aliphatic, aromatic, straight chain, cyclic, bicyclic, branched, saturated and unsaturated hydrocarbon parts. However, when the hydrocarbyl residue is described as substituted, it can optionally contain heteroatoms on the carbon and hydrogen components of the substituted residue. Therefore, when specifically described as substituted, the hydrocarbyl residue can also contain one or more carbonyl groups, amino groups, hydroxyl groups, etc., or it can contain heteroatoms within the main chain of the hydrocarbyl residue. As an example, Z 1 It may be a dibutylaminomethyl group formed by the reaction of a terminal 3,5-dimethyl-1,4-phenyl group with the dibutylamine component of an oxidative polymerization catalyst.

[0020] In one aspect, x in the above formula can be 1, and the sulfonated poly(phenylene ether) comprises repeating units of the formula:

[0021]

[0022] Among them, Z 1 and Z 2 As defined above.

[0023] In one aspect, x in the above formula can be 2, and the sulfonated poly(phenylene ether) can comprise repeating units of the formula:

[0024]

[0025] Among them, Z 1 and Z 2 As defined above.

[0026] The sulfonated poly(phenylene ether) of the present disclosure is sulfonated, and therefore, it will be understood that Z 1 or Z 2At least a portion of is substituted with a sulfo group (eg, a sulfonic acid group or a sulfonyl chloride group).

[0027] In one aspect, the poly(phenylene ether) may include 2,6-dimethyl-1,4-phenylene ether repeating units, 2,3,6-trimethyl-1,4-phenylene ether repeating units, 2,5-dimethyl-1,4-phenylene ether repeating units, 2,2',5,5'-tetramethyl-4,4'-dihydroxydiphenyl ether repeating units, 2-methyl-6-phenyl-1,4-phenylene ether repeating units, 2,2'-dimethyl-6,6'-diphenyl-4,4'-dihydroxy Diphenyl ether repeating unit, 2,6-diphenyl-1,4-phenylene ether repeating unit, 2,2',6,6'-tetraphenyl-4,4'-dihydroxydiphenyl ether repeating unit, 2,6-dimethoxy-1,4-phenylene ether repeating unit, 2,2'-6,6'-tetramethoxy-4,4'-dihydroxydiphenyl ether, 3,3',5,5'-tetramethyl-4,4'-dihydroxydiphenyl ether unit, their sulfonated derivatives or their combinations. As used herein, the term "their sulfonated derivatives" refers to the above-mentioned repeating units having at least one substituent substituted by a sulfonic group. For example, the sulfonated poly(phenylene ether) may include 2,6-dimethyl-3-sulfo-1,4-phenylene ether repeating units, 2,5-dimethyl-3-sulfo-1,4-phenylene ether repeating units, 2,2',5,5'-tetramethyl-3-sulfo-4,4'-dihydroxydiphenyl ether repeating units, 2-methyl-6-phenyl-3-sulfo-1,4-phenylene ether repeating units, 2,2'-dimethyl-6,6'-3-sulfo 2,6-diphenyl-4,4'-dihydroxydiphenyl ether repeating units, 2,6-diphenyl-3-sulfo-1,4-phenylene ether repeating units, 2,2',6,6'-tetraphenyl-3-sulfo-4,4'-dihydroxydiphenyl ether repeating units, 2,6-dimethoxy-3-sulfo-1,4-phenylene ether repeating units, 2,2'-6,6'-tetramethoxy-3-sulfo-4,4'-dihydroxydiphenyl ether, or a combination thereof.

[0028] In one aspect, the sulfonated poly(phenylene ether) can include 2,6-dimethyl-1,4-phenylene ether units and 2,6-dimethyl-3-sulfo-1,4-phenylene ether repeating units. In other words, the sulfonated poly(phenylene ether) can be a sulfonated poly(2,6-dimethyl-1,4-phenylene ether).

[0029] The sulfonated poly(phenylene ether) has a degree of sulfonation of 20% to 50%. As described in further detail below, the degree of sulfonation can be determined, for example, using proton nuclear magnetic resonance ( 1 H NMR) spectroscopy. Therefore, at least one occurrence of Z in the above formula is 1 or Z 2is a sulfonic group in at least 20% of the repeating units of the sulfonated poly(phenylene ether).Within this range, the sulfonated poly(phenylene ether) may have a degree of sulfonation of 20 to 50%, or 20 to 45%, or 20 to 40%, or 20 to 35%.

[0030] The sulfonated poly(phenylene ether) may optionally contain molecules having aminoalkyl-containing end groups, typically located in an ortho position to the hydroxy group.Also frequently present are tetramethyldiphenoquinone (TMDQ) end groups, typically obtained from a 2,6-dimethylphenol-containing reaction mixture in which tetramethyldiphenoquinone byproduct is present.

[0031] The poly(phenylene ether) from which the sulfonated poly(phenylene ether) can be prepared can be in the form of a homopolymer, a copolymer, a graft copolymer, an ionomer, a block copolymer, or an oligomer, and combinations thereof. In one aspect, the poly(phenylene ether) from which the sulfonated poly(phenylene ether) is prepared can be a poly(2,6-dimethyl-1,4-phenylene ether) having an intrinsic viscosity of 0.03 to 2 deciliters per gram (dl / g). For example, the poly(phenylene ether) can have an intrinsic viscosity of 0.25 to 1.7 dl / g, specifically 0.25 to 0.7 dl / g, more specifically 0.35 to 0.55 dl / g, and even more specifically 0.35 to 0.50 dl / g, measured using an Ubbelohde viscometer in chloroform at 25°C.

[0032] The sulfonated poly(phenylene ether) advantageously has a low sulfonyl chloride content. Specifically, the sulfonated poly(phenylene ether) has a sulfonyl chloride (—SO2Cl):sulfonic acid (—SO3H) molar ratio of less than or equal to 0.06. For example, the sulfonyl chloride (—SO2Cl):sulfonic acid (—SO3H) molar ratio can be less than or equal to 0.05, or less than 0.05, or less than or equal to 0.04, or greater than 0 to 0.04, or 0.001 to 0.04, or 0.01 to 0.04, or 0.02 to 0.04, or 0.03 to 0.04.

[0033] In one aspect, the sulfonated poly(phenylene ether) can have a degree of sulfonation relative to the sulfonyl chloride groups of less than 1.25%. In other words, the sulfonated poly(phenylene ether) contains less than 1.25 sulfonyl chloride groups per 100 repeating units. Within this range, the sulfonated poly(phenylene ether) can have a degree of sulfonation relative to the sulfonyl chloride groups of less than or equal to 1.2%, e.g., 0.1 to 1.2%.

[0034] The sulfonated poly(phenylene ether) can have a number average molecular weight of 60,000 to 100,000 g / mole, a weight average molecular weight of 130,000 to 200,000 g / mole, and a dispersity of 1.8 to 2.5. The number average molecular weight, weight average molecular weight, and dispersity are determined using gel permeation chromatography in dimethylformamide relative to polystyrene standards, as further described in the working examples below.

[0035] The sulfonated poly(phenylene ether) may contain reduced levels of oligomers. As used herein, the term "oligomer" refers to oligomers having less than 1000 atomic mass units (amu; used interchangeably with Daltons (Da) or grams per mole (g / mol). For example, the sulfonated poly(phenylene ether) may contain less than 1 weight percent, or less than 0.75 weight percent, or less than 0.5 weight percent of oligomers having a molecular weight of less than 1,000 grams per mole, wherein the weight percent is based on the total weight of the sulfonated poly(phenylene ether). In one aspect, the sulfonated poly(phenylene ether) may contain less than 0.7 weight percent, or less than 0.5 weight percent, or less than 0.4 weight percent of oligomers having a molecular weight of less than 500 grams per mole, wherein the weight percent is based on the total weight of the sulfonated poly(phenylene ether).

[0036] The sulfonated poly(phenylene ether) can advantageously exhibit an ion exchange capacity (IEC) of 1.2 to 2.5, or 1.5 to 2.5 milliequivalents per gram of sulfonated poly(phenylene ether). Unexpectedly, the inventors have discovered that lower levels of sulfonyl chloride in the sulfonated poly(phenylene ether) can provide improved IEC. It has been advantageously discovered that reduced sulfonyl chloride content correlates with the flow rate of the overhead nitrogen purge, as further described below.

[0037] In a specific aspect, the sulfonated poly(phenylene ether) may include sulfonated 2,6-dimethyl-1,4-phenylene ether units. The sulfonated poly(phenylene ether) may have a degree of sulfonation of 20 to 35%. The sulfonated poly(phenylene ether) may have a sulfonyl chloride (-SO2Cl): sulfonic acid (-SO3H) molar ratio of 0.01 to 0.04. In one aspect, the sulfonated poly(phenylene ether) may have a sulfonyl chloride (-SO2Cl) content of less than 1.2%, preferably 0.1 to less than 1.2%. The sulfonated poly(phenylene ether) may contain less than 0.5 weight percent of oligomers having a molecular weight of less than 1,000 grams per mole, wherein the weight percent is based on the total weight of the sulfonated poly(phenylene ether). The sulfonated poly(phenylene ether) may have a number average molecular weight of 60,000 to 100,000 g / mole, a weight average molecular weight of 130,000 to 200,000 g / mole, a dispersibility of 1.8 to 2.5, and an ion exchange capacity of 1.2 to 2.5 milliequivalents / gram of the sulfonated poly(phenylene ether), preferably 1.5 to 2.5 milliequivalents / gram of the sulfonated poly(phenylene ether).

[0038] The sulfonated poly(phenylene ether) can be prepared by a method comprising dissolving the poly(phenylene ether) in 1,2-dichloroethane to form a mixture. The poly(phenylene ether) starting material can include a poly(phenylene ether) comprising repeating structural units having the formula:

[0039]

[0040] Among them, each occurrence of Z 1 independently include halogen, unsubstituted or substituted C 1-12 Hydrocarbyl (provided that the hydrocarbyl group is not a tertiary hydrocarbyl), C 1-12 Hydrocarbon thio group, C 1-12 Hydroxyl, or C 2-12 haloalkyloxy (wherein at least two carbon atoms separate the halogen and oxygen atoms); each occurrence of Z 2 independently include hydrogen, halogen, unsubstituted or substituted C 1-12 Hydrocarbyl, provided that the hydrocarbyl group is not a tertiary hydrocarbyl, C 1-12 Hydrocarbon thio group, C 1-12 Hydroxyl, or C 2-12 haloalkyloxy (wherein at least two carbon atoms separate the halogen and oxygen atoms); and x is 1 or 2. In one aspect, Z 1 It may be a dibutylaminomethyl group formed by the reaction of a terminal 3,5-dimethyl-1,4-phenyl group with the dibutylamine component of an oxidative polymerization catalyst.

[0041] In one aspect, the poly(phenylene ether) may include 2,6-dimethyl-1,4-phenylene ether repeating units, 2,3,6-trimethyl-1,4-phenylene ether repeating units, 2,5-dimethyl-1,4-phenylene ether repeating units, 2,2',5,5'-tetramethyl-4,4'-dihydroxydiphenyl ether repeating units, 2-methyl-6-phenyl-1,4-phenylene ether repeating units, 2,2'-dimethyl-6,6'-diphenyl-4,4'-dihydroxydiphenyl ether repeating units, 2,6-diphenyl-1,4-phenylene ether repeating units. The poly(phenylene ether) may be a poly(2,6-dimethyl-1,4-phenylene ether) having an intrinsic viscosity of 0.03 to 2 deciliters per gram (dl / g). Within this range, the poly(phenylene ether) can have an intrinsic viscosity of 0.25 to 1.7 dl / g, specifically 0.25 to 0.7 dl / g, more specifically 0.35 to 0.55 dl / g, even more specifically 0.35 to 0.50 dl / g as measured using an Ubbelohde viscometer in chloroform at 25°C.

[0042] In one aspect, the poly(phenylene ether) can comprise molecules having aminoalkyl-containing end groups, typically located in an ortho position to the hydroxyl group. Also often present are tetramethyldiphenoquinone (TMDQ) end groups, typically obtained from a reaction mixture containing 2,6-dimethylphenol in which tetramethyldiphenoquinone byproduct is present. The poly(phenylene ether) can be in the form of a homopolymer, copolymer, graft copolymer, ionomer, block copolymer, or oligomer, and combinations thereof.

[0043] A mixture of poly(phenylene ether) and solvent can be provided at a temperature of 10° C. to 85° C., e.g., 10° C. to 60° C., or 25° C. to 40° C. A sufficient amount of 1,2-dichloroethane can be present to dissolve the poly(phenylene ether). In one aspect, the mixture can include 1 to 20 wt % poly(phenylene ether); and 80 to 99 wt % 1,2-dichloroethane.

[0044] The solvent mixture can then be combined with a sulfonating agent to sulfonate the poly(phenylene ether). The combination of the solvent mixture and the sulfonating agent is further carried out in the presence of a co-solvent, preferably ethyl acetate. Alternative exemplary co-solvents can be, for example, those described in International Publication No. 2020 / 254885, the contents of which are incorporated herein in their entirety.

[0045] The sulfonation reaction can be carried out at a temperature of up to 85°C, such as 10°C to 85°C, or 10°C to 60°C, or 25°C to 40°C. The amount of the sulfonating agent added to the solvent mixture can be 0.5 to 1 mole, preferably 0.25 to 0.9 mole, per mole of poly(phenylene ether) dissolved in the solvent mixture. The specific amount of the sulfonating agent added depends on the desired sulfonation level in the sulfonation reaction product. The sulfonating agent can be added slowly to the solvent mixture, for example, over a period of 15 to 60 minutes (min) (e.g., over a period of 30 min). Once the sulfonating agent and co-solvent are combined with the solvent mixture, the resulting reaction mixture can be stirred before precipitation, for example, for a period of 60 to 210 minutes. The stirring can be at a stirring rate that effectively maintains the reaction mixture as uniform, for example, at a stirring rate of 50 to 1,000 revolutions per minute (RPM). In one aspect, the agitation rate can be selected to provide an impeller tip speed of 1 to 8 meters per second (m / s), or 1 to 5 m / s, or 2 to 4 m / s.

[0046] The sulfonating agent is preferably added with a cosolvent, which may desirably prevent precipitation of the sulfonated poly(phenylene ether) before the desired degree of sulfonation has been achieved. The sulfonating agent and the cosolvent may preferably be present in a weight ratio of 1:1.5 to 1.5:1, preferably 1:1.1 to 1.1:1.

[0047] In the sulfonation reaction process, nitrogen can flow through the reaction mixture. Do not wish to be bound by theory, it is believed that making nitrogen flow through the reaction mixture at a specific rate can help reduce the amount of sulfonyl chloride groups in the sulfonated product, for example, by removing HCl by-products. In aspect, nitrogen can be made to pass through the mixture at a flow rate greater than or equal to 20 ml / min / mole of sulfonating agent. Within this range, nitrogen can be made to pass through the reaction mixture at a flow rate of 20 to 1500 ml / min / mole of sulfonating agent, or 25 to 1500 ml / min / mole of sulfonating agent, or 25 to 1300 ml / min / mole of sulfonating agent, or 25 to 1050 ml / min / mole of sulfonating agent, or 25 to 250 ml / min / mole of sulfonating agent. Aforesaid nitrogen flow rate can be used for a reactor occupancy greater than or equal to 30%.

[0048] The sulfonated poly(phenylene ether) can be precipitated from the solvent mixture using an anti-solvent mixture, e.g., comprising deionized (DI) water. In one aspect, at least one of hexane, heptane, e.g., together with deionized water, can be used to precipitate the sulfonated poly(phenylene ether) from the reaction mixture. The reaction mixture can be added (e.g., slowly) to the anti-solvent mixture, wherein the anti-solvent mixture can be used in an amount sufficient to cause precipitation. For example, 100 grams (g) of the reaction mixture can be added to 300 g to 700 g, preferably 390 g to 595 g of the anti-solvent mixture, wherein the weight ratio of hexane to water ranges from 0 to 1.15.

[0049] The precipitated sulfonated poly(phenylene ether) can be filtered, and optionally washed and dried. The filtrate can be biphasic, wherein 1,2-dichloroethane, co-solvent, and optionally one or more organics (e.g., hexane) are part of the anti-solvent mixture as the organic phase and water as the aqueous phase. Therefore, the filtrate can be further processed to recover at least one of 1,2-dichloroethane, co-solvent, or water; preferably 1,2-dichloroethane and co-solvent are recovered, more preferably 1,2-dichloroethane, co-solvent, and water are recovered. Recovering the material can include decanting the biphasic filtrate to form an aqueous stream and an organic stream. The organic stream can be further processed (e.g., distilled) to recover 1,2-dichloroethane and / or co-solvent. The recovered material can be recycled.

[0050] exist Figure 1An exemplary method for making a sulfonated poly(phenylene ether) according to the present disclosure is schematically shown in . As shown, the method requires introducing the poly(phenylene ether) and 1,2-dichloroethane into a mixing vessel 10. The mixing vessel 10 can be maintained at room temperature up to 85°C, for example, 30°C to 85°C, or 30 to 60°C, preferably 30°C to 45°C. Within the mixing vessel 10, the poly(phenylene ether) and 1,2-dichloroethane can be mixed, for example, until uniform, to form a solvent mixture. Optionally, mixing can be continued until a uniform clear solution is obtained. From the mixing vessel 10, the solvent mixture can be treated in a reaction vessel 20 with a sulfonating agent and a co-solvent (e.g., ethyl acetate). Nitrogen can be passed through the reaction mixture in the reaction vessel 20 to promote a low degree of sulfonyl chloride. Then, for example, once the desired degree of sulfonation has been obtained, the sulfonated poly(phenylene ether) can be precipitated from the mixture in a precipitation unit 30. For example, the reaction solvent mixture can be slowly added to the anti-solvent mixture (e.g., of hexane and DI water) to induce precipitation of the sulfonated poly(phenylene ether). For example, the precipitated sulfonated poly(phenylene ether) can be separated from the liquid phase, for example, in the filtration unit 40, before optionally washing (e.g., with DI water) the sulfonated poly(phenylene ether) (e.g., in the washing units 50, 52), and drying (e.g., in the dryer 54) the sulfonated poly(phenylene ether). The wash from the washing units 50, 52 can optionally be separated into an aqueous stream and a hexane stream in the decantation unit 56. The hexane stream can optionally be recycled to the reslurry unit 50. At the same time, the liquid phase from the filtration unit 40 can be treated to remove water, for example, using liquid-liquid separation in the decantation unit 60. The aqueous recovery phases from the decantation unit 60 and from the decantation unit 56 can be treated in a multiple effect evaporator (MEE) 70 to recover water. The generated water may optionally be recycled, for example, to the reslurry unit 50, the washing unit 52, or the precipitation unit 30; and preferably to the reslurry unit 50. The 1,2-dichloroethane (EDC) stream from the decanting unit 60 may be further processed by distillation in unit 80 to separate the EDC. The separated EDC may optionally be recycled, for example, to the mixing vessel 10.

[0051] Sulfonated poly (phenylene ether) can be used for a variety of products. For example, sulfonated poly (phenylene ether) can be used for ion exchange membranes (e.g., for dialysis), proton conducting membranes (e.g., for polymer electrolyte membrane fuel cells), ion exchange membranes for flow batteries, hollow fiber membranes, precursors for molecular sieve carbon membranes for gas separation, precursors for carbon electrodes for fuel cells, carbon membrane reactors, etc. Therefore, a membrane comprising sulfonated poly (phenylene ether) represents another aspect of the present disclosure. For example, a membrane comprising sulfonated poly (phenylene ether) can be prepared optionally on a substrate by casting a membrane comprising sulfonated poly (phenylene ether). Exemplary substrates can include, for example, woven synthetic fabrics (e.g., polypropylene cloth, polyacrylonitrile cloth, polyacrylonitrile-co-vinyl chloride cloth, polyvinyl chloride cloth, polyester cloth, etc.), glass filter cloth, polyvinylidene chloride screen, glass paper, treated cellulose battery paper, polystyrene coated glass fiber mat, polyvinyl chloride battery paper, etc. Any suitable casting method can be used, such as solution casting, drop casting, spin coating, scraper coating, roller coating, etc. or a combination thereof. The membrane preferably comprises at least one layer comprising a sulfonated poly(phenylene ether). Precursors of porous carbon represent another aspect of the present disclosure. Porous carbon can be used, for example, as a molecular sieve carbon membrane for gas separation. Porous carbon molecular sieve membranes can be made, for example, by pyrolysis of a precursor polymer comprising a sulfonated poly(phenylene ether) of the present disclosure. The porous carbon can have micropores (e.g., having a diameter of 0.01 microns or less), macropores (e.g., having a diameter of 0.01 to 100 microns), or a combination thereof.

[0052] The present disclosure is further illustrated by the following examples, which are non-limiting.

[0053] Example

[0054] The following exemplary procedure was used to prepare the sulfonated poly(phenylene ether).

[0055] A reactor equipped with an agitator is maintained at 40°C. Poly(phenylene ether) (PPE) resin (10 parts by weight) is dissolved in 1,2-dichloroethane (93.9 parts by weight) until a uniform clear solution is obtained (e.g., 60 minutes). As further described below, the relative proportions of poly(phenylene ether) and 1,2-dichloroethane can be varied. The temperature is maintained at 40°C. Chlorosulfonic acid (5.7 parts by weight) and ethyl acetate (6.1 parts by weight) are transferred to the reactor under vigorous stirring and over a period of 40 minutes. The relative proportions of chlorosulfonic acid and ethyl acetate may also vary depending on the desired degree of sulfonation, as further described below. A nitrogen purge is maintained through the headspace of the reaction mixture, and rapid stirring is maintained. The rate at which nitrogen gas flows through the headspace of the reaction mixture is varied, as further described below. Once the desired degree of sulfonation is obtained, as measured by proton nuclear magnetic resonance ( 1H NMR) spectroscopy, the reaction mixture is then slowly transferred to a wash vessel comprising DI water (500 ml) at a temperature of 10°C and equipped with a 4-blade stirrer of approximately 60 mm in diameter, which is operated at 1,000 rpm, giving a tip speed of 3.14 m / s. After 1 hour, the temperature is then raised to 25°C. Stirring is continued for a total of 30 minutes. It is then filtered. It is then washed in a DI water / hexane mixture (200 ml DI water; 19.7 ml hexane) and filtered again. The residue is washed thoroughly with DI water (200 ml per wash) until a neutral pH is obtained, as determined by potentiometric titration. The sulfonated material is then dried under vacuum at room temperature (e.g., 25°C) for up to 72 hours.

[0056] The degree of substitution (also called the degree of sulfonation or the level of sulfonation) indicates the percentage of repeating units along the sulfonated polymer molecular chain that bear sulfonic acid groups. The degree of substitution (DS) is determined by nuclear magnetic resonance (NMR) spectroscopy. The sample is dissolved in dimethyl sulfoxide-d6 (DMSO-d6, also called deuterated DMSO) (with the help of overnight shaking in a horizontal shaker) and 32 scans are averaged with a 5 second delay. In the case of undissolved parts, the solvent vial is sonicated in a 45°C water bath for 15-30 minutes.

[0057] The degree of sulfonation can be calculated from aliphatic or aromatic protons:

[0058] Consider the aromatic protons:

[0059]

[0060] Consider aliphatic protons:

[0061]

[0062] where I is the integrated value of the NMR chemical shift at a given ppm.

[0063] The molecular weight of sulfonated poly(phenylene ether) was determined by gel permeation chromatography (GPC) using dimethylformamide as the mobile phase with 0.1 wt% lithium bromide as an additive based on the weight of the mobile phase. Agilent 2x (e.g., 2 columns) PLgel 5 microns (μm) MIXED-B, 300x 7.5 mm, with a guard column, was used to elute the sPPE at a flow rate of 1 ml / min and a column temperature of 50°C. The GPC chromatogram of the sPPE was recorded using an ultraviolet (UV) detector (at 275 nanometers (nm)) with an elution time of 30 minutes. The sample was slowly dissolved in dimethylformamide solvent at a concentration of 3 milligrams per milliliter (mg / ml) in a horizontal oscillator for about 4 to 6 hours. The solution was filtered through a 0.45 μm PTFE filter into a GPC autosampler vial for analysis. The GPC system was calibrated using polystyrene standards ranging from 580 Daltons (Da) to 6570 kDa. Baseline points were set using Shimadzu Labsolution software. Dispersion Index According to the following determination:

[0064]

[0065] Oligomer content is to use the slice data produced by GPC software and the GPC chromatogram obtained for each sample using the above method to determine. Use this software to "slice" chromatogram and calculate the molecular weight and content of each slice. For each sample, determine the oligomer content of the oligomer with a molecular weight of <1000amu and <500amu.

[0066] As shown in Table 2 below, the processes described herein provide sulfonated poly(phenylene ether) having a high degree of sulfonation (e.g., greater than 15%), retaining a high molecular weight (e.g., Mn greater than 60,000 g / mole), and having low levels of residual oligomers.

[0067] Table 2

[0068]

[0069] Table 2 (continued)

[0070]

[0071] Without wishing to be bound by theory, it is believed that the presence of sulfonyl chloride groups in the sulfonated poly(phenylene ether) does not contribute to the ion exchange capacity of the material. Therefore, in order to provide a material with improved ion exchange capacity, it would be advantageous to provide a sulfonated poly(phenylene ether) with reduced sulfonyl chloride content.

[0072] To this end, the inventors attempted to reduce the sulfonyl chloride content using an overhead nitrogen purge to minimize or eliminate the formation of sulfonyl chloride in the sulfonated poly(phenylene ether) product. As shown in Table 3, the inventors unexpectedly discovered that the rate at which nitrogen is passed through the reaction mixture can affect the sulfonyl chloride content in the sulfonated poly(phenylene ether) produced. Advantageously, it was discovered that the sulfonated poly(phenylene ether) with reduced sulfonyl chloride content provides improved IEC.

[0073] IEC represents the number of milliequivalents of ions in 1 g of dry polymer. IEC is determined by dissolving sPPE in a dimethylacetamide / isopropanol mixture and titrating with potassium hydroxide alcohol by potentiometric method. This non-aqueous titration is performed with a Solvatrode (commercially available from Metrohm USA) as an electrode. The method uses a two-solvent system. Therefore, a sharp and reproducible endpoint is obtained.

[0074] The samples were dissolved in dimethylacetamide and diluted with isopropanol to obtain reproducible ion exchange capacity. Using dimethylacetamide alone, no sharp endpoints with significant variability were obtained in replicate analyses. Without being limited by theory, it is believed that this dual solvent system helps control polarity and enables reproducible, sharp endpoints to be obtained.

[0075]

[0076] Where: A = volume of 0.1N potassium hydroxide (KOH) solution in ml required for titration;

[0077] B = volume of 0.1N KOH solution required for blank in ml;

[0078] F = normality of 0.1N KOH solution; and

[0079] S = sample weight (grams).

[0080] The concentrations of sulfonic acid (SO3H) and sulfonyl chloride (SO2Cl) groups were determined by measuring the total concentrations of elemental sulfur (S) and chlorine (Cl) using elemental analysis using CHNS and combustion ion chromatography, respectively. The free amounts of elemental S (measured as sulfate) and Cl (measured as chloride) were determined using extractable ion chromatography.

[0081] Table 3 below provides the amounts or ratios of various reaction components for Examples 2-12 and further examines the effect of nitrogen purge rate on sulfonyl chloride content. The amounts of various residual components, degree of sulfonation, and ion exchange capacity (IEC) of each example are provided.

[0082] Table 3

[0083]

[0084]

[0085] Table 3 (continued)

[0086]

[0087] As shown in Tables 2 and 3, the processes described herein provide sulfonated poly(phenylene ether) products having a degree of sulfonation (DS) ranging from 16.8% to 31.8%. This total degree of sulfonation includes both -S03H and -S02Cl groups. As described above, the degree of sulfonation can be further decomposed into the percentage of -S03H and the percentage of -S02Cl, which make up the total DS, by analyzing the total and free amounts of elemental S and Cl using CHNS, combustion ion chromatography, and extractable ion chromatography.

[0088] Table 3 further shows the relationship between the nitrogen purge rate in the headspace during the sulfonation reaction and the resulting -SO2Cl content. Examples 2-8 exhibited -SO2Cl content of less than 1.2% (e.g., 0.77%-1.17%) using N2 scans at a rate of 50-100 ml / min (corresponding to normalized N2 scan rates of 81.8 to 204.4 ml / min per mole CSA). Examples 2-8 each exhibited a molar ratio of -SO2Cl:-SO3H of 0.04 or less (e.g., 0.03 to 0.04).

[0089] Each of these embodiments further retains a high molecular weight, as shown in Table 2, with an Mn of 77,000 to 97,000 g / mol, an Mw of 158,000 to 190,000, and a dispersity of 2.0 to 2.1. The oligomer content is also advantageously minimized, with each embodiment having 0.5 wt % or less of oligomers with a molecular weight of 1000 amu or less. Oligomers with a molecular weight of 500 amu or less are limited to less than 0.4 wt %.

[0090] Examples 1 and 9-12 each exhibited a -SO2Cl content of 0.92-1.86, and a molar ratio of -SO2Cl:-SO3H of 0.05 to 0.06. It should be noted that, with equivalent reactants, the N2 purge rates of Examples 1 and 9-12 were less than the N2 purge rates of Examples 2-8 (see, e.g., "Normalized N2 Purge" in Table 3, where the N2 purge rates have been normalized based on the amount (e.g., moles) of CSA used).

[0091] Table 3 also shows that, in general, having a reduced -SO2Cl content (e.g., DS SO2Cland a molar ratio of -SO2Cl:-SO3H below 0.04) showed increased IEC (e.g., IEC above 1.87 meq / g). SO2Cl ) generally exhibit reduced IEC (e.g., 1.17-1.77 meq / gram or less).

[0092] Thus, sulfonated poly(phenylene ether) having a combination of a degree of sulfonation of 20%-50%, a number average molecular weight of 60,000 to 100,000 g / mole, a dispersity of 2.0 to 2.1, and reduced amounts of -SO2Cl are advantageously provided by the present disclosure.

[0093] The present invention further encompasses the following aspects.

[0094] Aspect 1: Sulfonated poly(phenylene ether) comprising: repeating units of the formula

[0095]

[0096] 20% to 50% degree of sulfonation, as determined by nuclear magnetic resonance spectroscopy; and a sulfonyl chloride (-SO2Cl):sulfonic acid (-SO3H) molar ratio of less than or equal to 0.06; wherein, in the above formula, Z 1 is independently at each occurrence sulfonic acid, sulfonyl chloride, halogen, unsubstituted or substituted C 1-12 Hydrocarbyl (provided that the hydrocarbyl group is not a tertiary hydrocarbyl), C 1-12 Hydrocarbon thio group, C 1-12 Hydroxyl, or C 2-12 A haloalkyloxy group (wherein at least two carbon atoms separate the halogen and oxygen atoms); Z 2 is independently at each occurrence sulfonic acid, sulfonyl chloride, hydrogen, halogen, unsubstituted or substituted C 1-12 Hydrocarbyl (provided that the hydrocarbyl group is not a tertiary hydrocarbyl), C 1-12 Hydrocarbon thio group, C 1-12 Hydroxyl, or C 2-12 halohydrocarbyloxy (wherein at least two carbon atoms separate the halogen and oxygen atoms); and x is 1 or 2.

[0097] Aspect 2: A sulfonated poly(phenylene ether) according to Aspect 1, wherein the sulfonyl chloride (-SO2Cl):sulfonic acid (-SO3H) molar ratio is less than or equal to 0.05, or less than 0.05, or less than or equal to 0.04, or greater than 0 to 0.04, or 0.001 to 0.04, or 0.01 to 0.04, or 0.02 to 0.04, or 0.03 to 0.04.

[0098] Aspect 3: The sulfonated poly(phenylene ether) according to aspect 1 or 2, wherein the sulfonated poly(phenylene ether) comprises 2,6-dimethyl-1,4-phenylene ether repeating units, 2,3,6-trimethyl-1,4-phenylene ether units, 2,5-dimethyl-1,4-phenylene ether repeating units, 2,2',5,5'-tetramethyl-4,4'-dihydroxydiphenyl ether repeating units, 2-methyl-6-phenyl-1,4-phenylene ether repeating units, 2,2'-dimethyl-6,6'- -diphenyl-4,4'-dihydroxydiphenyl ether repeating units, 2,6-diphenyl-1,4-phenylene ether repeating units, 2,2',6,6'-tetraphenyl-4,4'-dihydroxydiphenyl ether repeating units, 2,6-dimethoxy-1,4-phenylene ether repeating units, 2,2'-6,6'-tetramethoxy-4,4'-dihydroxydiphenyl ether, 3,3',5,5'-tetramethyl-4,4'-dihydroxydiphenyl ether units, sulfonated derivatives thereof or combinations thereof.

[0099] Aspect 4: The sulfonated poly(phenylene ether) according to any one of aspects 1 to 3, wherein the sulfonated poly(phenylene ether) has a number average molecular weight of 60,000 to 100,000 g / mole, a weight average molecular weight of 130,000 to 200,000 g / mole, and a dispersity of 1.8 to 2.5, wherein the number average molecular weight, weight average molecular weight, and dispersity are determined using gel permeation chromatography in dimethylformamide relative to polystyrene standards.

[0100] Aspect 5: A sulfonated poly(phenylene ether) according to any of Aspects 1 to 4, wherein the sulfonated poly(phenylene ether) comprises less than 1 weight percent, or less than 0.75 weight percent, or less than 0.5 weight percent of oligomers having a molecular weight less than 1,000 grams per mole, wherein the weight percent is based on the total weight of the sulfonated poly(phenylene ether).

[0101] Aspect 6: A sulfonated poly(phenylene ether) according to any of Aspects 1 to 5, wherein the sulfonated poly(phenylene ether) contains less than 0.7 weight percent, or less than 0.5 weight percent, or less than 0.4 weight percent of oligomers having a molecular weight less than 500 g / mole, wherein the weight percent is based on the total weight of the sulfonated poly(phenylene ether).

[0102] Aspect 7: The sulfonated poly(phenylene ether) according to any one of aspects 1 to 6, wherein the sulfonated poly(phenylene ether) exhibits an ion exchange capacity of 1.5 to 2.5 milliequivalents per gram of the sulfonated poly(phenylene ether).

[0103] Aspect 8: A sulfonated poly(phenylene ether) according to Aspect 1, comprising sulfonated 2,6-dimethyl-1,4-phenylene ether units; a degree of sulfonation of 20 to 35%; a sulfonyl chloride (-SO2Cl):sulfonic acid (-SO3H) molar ratio of 0.01 to 0.04; and less than 0.5 wt% of an oligomer having a molecular weight of less than 1,000 g / mole, wherein the weight percentages are based on the total weight of the sulfonated poly(phenylene ether); wherein the sulfonated poly(phenylene ether) has a number average molecular weight of 60,000 to 100,000 g / mole, a weight average molecular weight of 130,000 to 200,000 g / mole, a dispersibility of 1.8 to 2.5, and an ion exchange capacity of 1.2 to 2.5 milliequivalents / gram of sulfonated poly(phenylene ether).

[0104] Aspect 9: A sulfonated poly(phenylene ether) according to any one of Aspects 1 to 8, wherein the sulfonated poly(phenylene ether) is prepared by a method comprising dissolving the poly(phenylene ether) in 1,2-dichloroethane to form a mixture; combining a sulfonating agent and a co-solvent, preferably ethyl acetate, with the mixture to form the sulfonated poly(phenylene ether), wherein nitrogen is passed through the mixture at a flow rate greater than or equal to 25 ml / min / mole of sulfonating agent; precipitating the sulfonated poly(phenylene ether); and isolating the precipitated sulfonated poly(phenylene ether).

[0105] Aspect 10: A method for preparing a sulfonated poly(phenylene ether) according to any one of Aspects 1 to 9, the method comprising: dissolving the poly(phenylene ether) in 1,2-dichloroethane to form a mixture; combining a sulfonating agent and a co-solvent, preferably ethyl acetate, with the mixture to form a sulfonated poly(phenylene ether), wherein nitrogen is passed through the mixture at a flow rate greater than or equal to 30 ml / min / mole of sulfonating agent; precipitating the sulfonated poly(phenylene ether); and isolating the precipitated sulfonated poly(phenylene ether).

[0106] Aspect 11: The method according to aspect 10, wherein the dissolving is at a temperature of 30°C to 85°C.

[0107] Aspect 12: The method according to aspect 10 or 11, wherein the mixture comprises 1 to 20 wt% poly(phenylene ether); and 80 to 99 wt% 1,2-dichloroethane.

[0108] Aspect 13: The method according to any one of aspects 10 to 12, wherein the sulfonating agent and the co-solvent are present in a weight ratio of 1:1.5 to 1.5:1, preferably 1:1.1 to 1.1:1.

[0109] Aspect 14: A membrane comprising the sulfonated poly(phenylene ether) according to any of aspects 1 to 9.

[0110] Aspect 15: The membrane according to aspect 14, wherein the membrane is an ion exchange membrane.

[0111] Aspect 16: A precursor of porous carbon, the precursor comprising the sulfonated poly(phenylene ether) according to any one of aspects 1 to 9.

[0112] Aspect 17: The precursor according to aspect 17, wherein the porous carbon comprises micropores having a diameter less than 0.01 micrometers, macropores having a diameter of 0.01 to 100 micrometers, or a combination thereof.

[0113] Alternatively, the compositions, methods and articles may comprise, consist of or consist essentially of any suitable material, step or component disclosed herein. The compositions, methods and articles may additionally or alternatively be formulated so as to be free of or essentially free of any material (or species), step, or component that is otherwise not necessary for achieving the function or purpose of the compositions, methods and articles.

[0114] All ranges disclosed herein include endpoints, and endpoints can be combined independently of each other. "Combination" includes blends, mixtures, alloys, reaction products, etc. The terms "first", "second", etc. do not represent any order, quantity, or importance, but are used to distinguish one element from another. Unless otherwise specified herein or clearly contradictory to the context, the terms "one" and "one" and "the" do not represent the limitation of quantity, but are interpreted as covering the singular and plural. Unless otherwise clearly stated, "or" means "and / or". Throughout the specification, mentioning "an aspect" means that the specific elements described in conjunction with the aspect are included in at least one aspect described herein, and may or may not be present in other aspects. The term "their combination" as used in this article includes one or more listed elements, and is open, allowing one or more unnamed similar elements to exist. In addition, it should be understood that the described elements can be combined in any suitable manner in various aspects.

[0115] Unless specified to the contrary herein, all test standards are the most current standards in effect as of the filing date of this application, or, if priority is claimed, the filing date of the earliest priority application in which the test standards appear.

[0116] Unless otherwise defined, technical and scientific terms used herein have the same meanings as those generally understood by those of ordinary skill in the art to which this application belongs. All cited patents, patent applications, and other references are incorporated herein by reference in their entirety. However, if a term in this application contradicts or conflicts with a term in a combined reference, the term from this application takes precedence over the conflicting term from the combined reference.

[0117] Compounds are described using standard nomenclature. For example, any position not substituted by any indicator group is understood to have its valency filled by a bond or hydrogen atom as indicated. A dash ("-") not between two letters or symbols is used to indicate the point of attachment of a substituent. For example, -CHO is connected through the carbon of a carbonyl group.

[0118] As used in this article, the term "alkyl", whether used alone or as a prefix, suffix or fragment of another term, refers to a residue containing only carbon and hydrogen. The residue can be aliphatic or aromatic, straight chain, cyclic, bicyclic, branched, saturated or unsaturated. It can also include a combination of aliphatic, aromatic, straight chain, cyclic, bicyclic, branched, saturated and unsaturated hydrocarbon parts. However, when the alkyl residue is described as substituted, it can optionally include heteroatoms on and above the carbon and hydrogen members of the substituent residue. Therefore, when specifically described as substituted, the alkyl residue can also include one or more carbonyls, amino, hydroxyl, etc., or it can include heteroatoms in the main chain of the alkyl residue. The term "alkyl" refers to a branched or straight chain, saturated aliphatic hydrocarbon group, for example, methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, tert-butyl, n-pentyl, sec-pentyl and n-hexyl and sec-hexyl. "Alkenyl" refers to a straight or branched monovalent hydrocarbon radical having at least one carbon-carbon double bond (e.g., vinyl (-HC=CH2)). "Alkoxy" refers to an alkyl radical attached via an oxygen (i.e., alkyl-O-), such as methoxy, ethoxy, and sec-butoxy. "Alkylene" refers to a straight or branched, saturated divalent aliphatic hydrocarbon radical (e.g., methylene (-CH2-) or propylene (-(CH2)3-)). "Cycloalkylene" refers to a divalent cyclic alkylene radical, -C n H 2n-x , wherein x is the number of hydrogens replaced by cyclization. "Cycloalkenyl" refers to a monovalent group having one or more rings and one or more carbon-carbon double bonds in the ring, wherein all ring members are carbon (e.g., cyclopentyl and cyclohexyl). "Aryl" refers to an aromatic hydrocarbon group containing a specified number of carbon atoms, such as phenyl, cycloheptatrienone, indanyl, or naphthyl. "Arylene" refers to a divalent aryl group. "Alkylidenearylene" refers to an arylidene group substituted by an alkyl group. "Arylalkylene" refers to an alkylene group substituted by an aryl group (e.g., benzyl). The prefix "halo" refers to a group or compound comprising one or more of fluorine, chlorine, bromine, or iodine substituents. There may be a combination of different halogen atoms (e.g., bromine and fluorine) or only chlorine atoms. The prefix "hetero" refers to a compound or group comprising at least one ring member of a heteroatom (e.g., 1, 2, or 3 heteroatoms), wherein the heteroatoms are each independently N, O, S, Si, or P. "Substituted" means that the compound or group is substituted with at least one (e.g., 1, 2, 3, or 4) substituents, each of which may be independently C 1-9Alkoxy, C 1-9 Haloalkoxy, nitro (-NO2), cyano (-CN), C 1-6 Alkylsulfonyl (-S(=O)2-alkyl), C 6-12 Arylsulfonyl (-S(=O)2-aryl), thiol (-SH), thiocyanate (-SCN), tosyl (CH3C6H4SO2-), C 3-12 Cycloalkyl, C 2-12 Alkenyl, C 5-12 Cycloalkenyl, C 6-12 Aryl, C 7-13 Arylalkylene, C 4-12 Heterocycloalkyl, and C 3-12 A heteroaryl group replaces a hydrogen provided that the normal valence of the substituted atom is not exceeded. The number of carbon atoms indicated in the group does not include any substituents. For example, -CH2CH2CN is a C2 alkyl group substituted with a nitrile.

[0119] While certain aspects have been described, alternatives, modifications, variations, improvements, and substantial equivalents that are not presently foreseeable or may not be foreseeable may occur to the applicant or others skilled in the art. Accordingly, the appended claims as filed and as they may be amended are intended to cover all such alternatives, modifications, variations, improvements, and substantial equivalents.

Claims

1. A sulfonated poly(phenylene ether) comprising: The repeating unit of the formula: A degree of sulfonation of 20% to 50% as determined by nuclear magnetic resonance spectroscopy; and A molar ratio of sulfonyl chloride (-SO2Cl):sulfonic acid (-SO3H) of less than or equal to 0.06; wherein, In the above formula, Z 1 is independently at each occurrence sulfonic acid, sulfonyl chloride, halogen, unsubstituted or substituted C 1-12 The hydrocarbon group condition is that the hydrocarbon group is not a tertiary hydrocarbon group, C 1-12 Hydrocarbon thio group, C 1-12 Hydroxyl, or C 2-12 A haloalkyloxy group in which at least two carbon atoms separate the halogen and oxygen atoms; Z 2 is independently at each occurrence sulfonic acid, sulfonyl chloride, hydrogen, halogen, unsubstituted or substituted C 1-12 The hydrocarbon group condition is that the hydrocarbon group is not a tertiary hydrocarbon group, C 1-12 Hydrocarbon thio group, C 1-12 Hydroxyl, or C 2-12 A haloalkyloxy group wherein at least two carbon atoms separate the halogen and oxygen atoms; and x is 1 or 2.

2. The sulfonated poly(phenylene ether) of claim 1, wherein the sulfonyl chloride (—SO2Cl):sulfonic acid (—SO3H) molar ratio is less than or equal to 0.05, or less than 0.05, or less than or equal to 0.04, or greater than 0 to 0.04, or 0.001 to 0.04, or 0.01 to 0.04, or 0.02 to 0.04, or 0.03 to 0.

04.

3. The sulfonated poly(phenylene ether) of claim 1 or 2, wherein the sulfonated poly(phenylene ether) comprises 2,6-dimethyl-1,4-phenylene ether repeating units, 2,3,6-trimethyl-1,4-phenylene ether units, 2,5-dimethyl-1,4-phenylene ether repeating units, 2,2',5,5'-tetramethyl-4,4'-dihydroxydiphenyl ether repeating units, 2-methyl-6-phenyl-1,4-phenylene ether repeating units, 2,2',6,5'-tetramethyl-4,4'-dihydroxydiphenyl ether repeating units, 6'-diphenyl-4,4'-dihydroxydiphenyl ether repeating units, 2,6-diphenyl-1,4-phenylene ether repeating units, 2,2',6,6'-tetraphenyl-4,4'-dihydroxydiphenyl ether repeating units, 2,6-dimethoxy-1,4-phenylene ether repeating units, 2,2'-6,6'-tetramethoxy-4,4'-dihydroxydiphenyl ether, 3,3',5,5'-tetramethyl-4,4'-dihydroxydiphenyl ether units, sulfonated derivatives thereof or combinations thereof.

4. The sulfonated poly(phenylene ether) according to any one of claims 1 to 3, wherein The sulfonated poly(phenylene ether) has 60,000 to 100,000 g / mol number average molecular weight, a weight average molecular weight of 130,000 to 200,000 g / mole, and Dispersity of 1.8 to 2.5, The number average molecular weight, weight average molecular weight and dispersity are determined using gel permeation chromatography in dimethylformamide relative to polystyrene standards.

5. The sulfonated poly(phenylene ether) of any one of claims 1 to 4, wherein the sulfonated poly(phenylene ether) comprises less than 1 weight percent, or less than 0.75 weight percent, or less than 0.5 weight percent of oligomers having a molecular weight less than 1,000 g / mole, wherein the weight percents are based on the total weight of the sulfonated poly(phenylene ether).

6. The sulfonated poly(phenylene ether) of any one of claims 1 to 5, wherein the sulfonated poly(phenylene ether) comprises less than 0.7 weight percent, or less than 0.5 weight percent, or less than 0.4 weight percent of oligomers having a molecular weight less than 500 g / mole, wherein the weight percents are based on the total weight of the sulfonated poly(phenylene ether).

7. The sulfonated poly(phenylene ether) of any one of claims 1 to 6, wherein the sulfonated poly(phenylene ether) exhibits an ion exchange capacity of 1.5 to 2.5 milliequivalents per gram of the sulfonated poly(phenylene ether).

8. The sulfonated poly(phenylene ether) of claim 1, comprising: Sulfonated 2,6-dimethyl-1,4-phenylene ether units; 20% to 35% sulfonation degree; 0.01 to 0.04 molar ratio of sulfonyl chloride (-SO2Cl):sulfonic acid (-SO3H); as well as less than 0.5 weight percent of oligomers having a molecular weight less than 1,000 g / mole, wherein the weight percent is based on the total weight of the sulfonated poly(phenylene ether); in, The sulfonated poly(phenylene ether) has 60,000 to 100,000 g / mol number average molecular weight, 130,000 to 200,000 g / mol weight average molecular weight, A dispersity of 1.8 to 2.5, and 1.2 to 2.5 milliequivalents per gram of sulfonated poly(phenylene ether) ion exchange capacity.

9. The sulfonated poly(phenylene ether) according to any one of claims 1 to 8, wherein the sulfonated poly(phenylene ether) is prepared by a process comprising: dissolving poly(phenylene ether) in 1,2-dichloroethane to form a mixture; combining a sulfonating agent and a cosolvent, preferably ethyl acetate, with the mixture to form a sulfonated poly(phenylene ether), wherein nitrogen is passed through the mixture at a flow rate greater than or equal to 25 ml / min / mole of sulfonating agent; precipitating the sulfonated poly(phenylene ether); and The precipitated sulfonated poly(phenylene ether) is isolated.

10. A method for preparing the sulfonated poly(phenylene ether) of any one of claims 1 to 9, the method comprising: dissolving poly(phenylene ether) in 1,2-dichloroethane to form a mixture; combining a sulfonating agent and a cosolvent, preferably ethyl acetate, with the mixture to form a sulfonated poly(phenylene ether), wherein nitrogen is passed through the mixture at a flow rate greater than or equal to 30 ml / min / mole of sulfonating agent; precipitating the sulfonated poly(phenylene ether); and The precipitated sulfonated poly(phenylene ether) is isolated.

11. The method according to claim 10, wherein: The dissolution is at a temperature of 30°C to 85°C.

12. The method according to claim 10 or 11, wherein the mixture comprises 1 wt % to 20 wt % of the poly(phenylene ether); and 80 wt% to 99 wt% 1,2-dichloroethane.

13. The process according to any one of claims 10 to 12, wherein the sulfonating agent and the co-solvent are present in a weight ratio of 1:1.5 to 1.5:1, preferably 1:1.1 to 1.1:

1.

14. A membrane comprising the sulfonated poly(phenylene ether) of any one of claims 1 to 9.

15. The membrane of claim 14, wherein the membrane is an ion exchange membrane or a gas separation membrane.

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