Organosilanes, ionic organosilanes, membrane compositions and membranes

Abstract

A dihalogenated organosilane is represented by formula (I): #imgabs0# Each X independently represents Cl, Br or I. Each Ar 1 independently represents a phenylene group optionally substituted by 1 to 4 alkyl groups selected from methyl or ethyl. 1 R independently represents an alkylene group having 2 to 18 carbon atoms. 2 R independently represents a methyl group or an ethyl group. 3 R independently represents an alkylene group having 1 to 18 carbon atoms. 4 independently represents an alkylene group having 2 to 18 carbon atoms, and n is an integer ranging from 0 to 5, inclusive. The ionic organosilane that can be prepared from the dihalogenated organosilane is represented by formula (II): #imgabs1# Also disclosed are membrane compositions and membranes containing the ionic organosilane.

Description

[0001] Government Rights

[0002] This invention was made with Government support under Cooperative Agreement DE-AR0000950 awarded by the U.S. Department of Energy. The U.S. Government may have certain rights in this invention. Background Art

[0003] Anion exchange membrane can be used in various electrochemical cells, such as in fuel cells, electrolyzers, storage batteries and electrodialysis cells.Previous anion exchange membranes have been prepared by various copolymers with cationic nitrogen-containing groups.These copolymers have been prepared by, for example, providing corresponding quaternary ammonium groups by making styrene-to-4-vinylbenzyl chloride copolymers react with various nitrogen-containing bases.The mechanical strength of the typical membrane formed in this way is not enough for purposes such as those mentioned above.For example, film is normally fragile and has low tensile strength. Summary of the invention

[0004] Toughening and improved elongation are desirable in anion exchange membranes used for carbon dioxide or water electrolysis, fuel cells, flow batteries, and similar electrochemical devices. The present disclosure provides ionic organosilanes suitable for inclusion in membrane polymers that can overcome the above-mentioned deficiencies of anion exchange membranes.

[0005] This is usually achieved by adding impact modifiers such as g Silicones as a second phase are used to toughen the polymer. However, in electrochemical membranes, such inert second phases take up volume, do not increase conductivity, and thus reduce the conductivity per unit volume relative to the same polymer without the additive. In addition, silicones can be chemically unstable even under mildly alkaline conditions.

[0006] The ionic organosilanes described in the present disclosure improve film elongation at break and toughness while having the unexpected combination of carrying functional groups that improve electrical conductivity and the beneficial effects of chemical stability under alkaline conditions.

[0007] In one aspect, the present disclosure provides a dihaloorganosilane represented by the formula:

[0008]

[0009] in:

[0010] Each X independently represents Cl, Br or I;

[0011] Each Ar 1 independently represents a benzylidene group optionally substituted by 1 to 4 alkyl groups selected from methyl or ethyl;

[0012] Each R 1independently represents an alkylene group having 2 to 18 carbon atoms;

[0013] Each R 2 independently represents a methyl group or an ethyl group;

[0014] Each R 3 independently represents an alkylene group having 1 to 18 carbon atoms;

[0015] Each R 4 independently represents an alkylene group having 2 to 18 carbon atoms; and

[0016] n is an integer ranging from 0 to 5, inclusive.

[0017] In another aspect, the present disclosure provides an ionic organosilane represented by the formula:

[0018]

[0019] in:

[0020] Each X independently represents Cl, Br or I;

[0021] Each Ar 1 independently represents a benzylidene group optionally substituted by 1 to 4 alkyl groups selected from methyl or ethyl;

[0022] Each R 1 independently represents an alkylene group having 2 to 18 carbon atoms;

[0023] Each R 2 independently represents a methyl group or an ethyl group;

[0024] Each R 3 independently represents an alkylene group having 1 to 18 carbon atoms;

[0025] Each R 4 independently represents an alkylene group having 2 to 18 carbon atoms;

[0026] Each R 5 independently represents H or methyl;

[0027] Each R 6 independently represents an alkyl group having 1 to 4 carbon atoms, or an allyl group; and

[0028] n is an integer ranging from 0 to 5, inclusive.

[0029] In yet another aspect, the present disclosure provides a film composition comprising the following components:

[0030] (a) A copolymer comprising the following divalent monomer units:

[0031] (i) as well as

[0032] (ii)

[0033] in:

[0034] R 5 represents H or methyl;

[0035] R 6 represents an alkyl group having 1 to 4 carbon atoms, or an allyl group; and

[0036] X represents Cl, Br or I, and

[0037] wherein monomer unit (i) and monomer unit (ii) are present in a respective molar ratio of 1.5:1 to 3:1; and

[0038] (b) an ionic organosilane compound represented by the following formula:

[0039]

[0040] in:

[0041] Each Ar 1 independently represents a benzylidene group optionally substituted by 1 to 4 alkyl groups selected from methyl or ethyl;

[0042] Each R 1 independently represents an alkylene group having 2 to 18 carbon atoms;

[0043] Each R 2 independently represents a methyl group or an ethyl group;

[0044] Each R 3 independently represents an alkylene group having 1 to 18 carbon atoms;

[0045] Each R 4 independently represents an alkylene group having 2 to 18 carbon atoms;

[0046] Each R 5 independently represents H or methyl;

[0047] Each R 6 independently represents an alkyl group having 1 to 4 carbon atoms, or an allyl group; and

[0048] n is an integer ranging from 0 to 5, inclusive; and

[0049] Component (a) and component (b) are present in a respective weight ratio of 99.5:0.5 to 98:2.

[0050] In yet another aspect, the present disclosure provides a film comprising the film composition according to the present disclosure.

[0051] As used in this article:

[0052] "Monomer unit" means the largest structural unit contributed by a single monomer molecule to the structure of a polymer;

[0053] "Benzene group" generally refers to a divalent benzene ring;

[0054] The o-phenylene group has the formula:

[0055] The m-phenylene group has the formula: and

[0056] The p-phenylene group has the formula:

[0057]

[0026] A further understanding of the features and advantages of the present disclosure will be achieved upon consideration of the detailed description and the appended claims. DETAILED DESCRIPTION

[0058] Organosilanes

[0059] Ionic organosilanes can be synthesized from precursor organosilanes represented by the following formula:

[0060]

[0061] wherein each of the various groups is independently selected as previously defined.

[0062] Throughout this manual:

[0063] Each X independently represents Cl, Br or I. Cl is generally preferred.

[0064] Each Ar 1 Independently represents a phenylene group optionally substituted by 1 to 4 alkyl groups selected from methyl or ethyl. The phenylene group may include an o-phenylene group, an m-phenylene group or a p-phenylene group. Usually p-phenylene group is preferred.

[0065] Each R 1 Independently represents an alkylene group (i.e., divalent) having 2 to 18 carbon atoms, preferably 2 to 8 carbon atoms, more preferably 2 or 3 carbon atoms, and even more preferably 2 carbon atoms. Exemplary alkylene groups include ethylene, propylene, butylene, isobutylene, pentylene, hexylene, cyclohexylene, octylene, decylene, dodecylene, tetradecylene, hexadecylene, and octadecylene.

[0066] Each R 2 Each independently represents a methyl group or an ethyl group, preferably a methyl group.

[0067] Each R 3 Independently represents an alkylene group (i.e., divalent) having 1 to 18 carbon atoms, preferably 2 to 8 carbon atoms, more preferably 2 to 6 carbon atoms, and even more preferably 2 to 4 carbon atoms. Exemplary alkylene groups include methylene, ethylene, propylene, butylene, isobutylene, pentylene, hexylene, cyclohexylene, octylene, decylene, dodecylene, tetradecylene, hexadecylene, and octadecylene.

[0068] Each R 4 Independently represents an alkylene group (i.e., divalent) having 2 to 18 carbon atoms, preferably 2 to 12 carbon atoms, more preferably 6 to 10 carbon atoms, and even more preferably 8 carbon atoms. Exemplary alkylene groups include ethylene, propylene, butylene, isobutylene, pentylene, hexylene, cyclohexylene, octylene, decylene, dodecylene, tetradecylene, hexadecylene, and octadecylene.

[0069] Each n is independently 0, 1, 2, 3, 4 or 5.

[0070] The precursor organosilane can be prepared, for example, by hydrosilylation coupling of a dihydrocarbosilane with a halomethyl-substituted aryl olefin using a hydrosilylation catalyst (e.g., a Pt catalyst such as H2PtCl6 or Karstedt's catalyst) according to the following reaction scheme:

[0071]

[0072] Among them, Ar 1 , R 1 -R 4 , X and n are as defined previously.

[0073] Exemplary dihydrocarbosilanes include 1,1,4,4-tetramethyl-1,4-disilylbutane, 1,1,4,4-tetraethyl-1,4-disilylbutane, 1,1-dimethyl-4,4-dimethyl-1,4-disilylbutane, 1,1,6,6-tetramethyl-1,6-disilylhexane, 1,1,8,8-tetramethyl-1,4-disilooctane, 1,1,10,10-tetramethyl-1,10-disiladecane, 1,1,12,12-tetramethyl-1,12-disiladodecane, 1,1,16,16-tetramethyl-1,16-disilohexadecane, 1,1,18,18-tetramethyl-1,18-disilooctane, 1,1,12,12,20,20-hexamethyl-1,12,20-trisilicosane. Dihydrocarbosilane can be prepared, for example, by reducing the corresponding chlorocarbosilane using lithium aluminum hydride according to conventional methods.

[0074] Suitable dihydrocarbosilanes and / or their dichlorinated precursor counterparts can be synthesized by known methods and / or obtained from commercial suppliers; for example, Gelest Inc., Morrisville, Pennsylvania; ABCR, Karlsruhe, Germany; Alfa Aesar, Chennai, India; and TCI America, Portland, Oregon.

[0075] Exemplary halomethylphenyl olefins include p-chloromethylstyrene, p-bromomethylstyrene, p-iodomethylstyrene, m-chloromethylstyrene, o-chloromethylstyrene, p-allyl(chloromethyl)benzene, m-allyl(chloromethyl)benzene, o-allyl(chloromethyl)benzene, 4-chloromethyl-2-methylstyrene, 4-chloromethyl-3-methylstyrene, p-chloromethyl-2-propenyl-benzene, and p-(chloromethyl)-1-butene-4-yl-benzene. Halomethylphenyl olefins are available from commercial suppliers such as, for example, Millipore-Sigma, Saint Louis, Missouri or TCI America, Portland, Oregon, and / or synthesized by known methods.

[0076] Ionic organosilanes

[0077] The above dihalogenoorganosilanes can be converted into ionic organosilanes by reaction with appropriate imidazoles. Typically, the reaction is carried out by combining the dihalogenoorganosilanes and imidazoles in a solvent and optionally heating.

[0078] Suitable imidazoles include 1-allylimidazole, 1-allyl-2-methylimidazole, 1-allyl-4-methylimidazole, 1-allyl-5-methylimidazole, 1-allyl-2,4-dimethylimidazole, 1-allyl-2,5-dimethylimidazole, 1-allyl-4,5-dimethylimidazole, 1-allyl-2,4,5-trimethylimidazole, 1-methylimidazole, 1,2-dimethylimidazole, 1,4-dimethylimidazole, 1,5-dimethylimidazole, 1,2,4-trimethylimidazole, 1,2,5-trimethylimidazole, 1,2,4,5-tetramethylimidazole, 1-ethylimidazole, 1-propylimidazole, 1-butylimidazole, 1-isobutylimidazole, 1-ethyl-2-methylimidazole, 1-ethyl-4-methylimidazole, 1-ethyl-5-methylimidazole, 1-ethyl-2,4-dimethylimidazole, 1-ethyl-2,5-dimethylimidazole, 1-ethyl-2,4,5-trimethylimidazole, 1-propyl-2-methylimidazole, 1-propyl-4-methylimidazole, 1-propyl-5-methylimidazole, 1-propyl-2,4-dimethylimidazole, 1-propyl-2,5-dimethylimidazole, 1-propyl-2,4,5-trimethylimidazole, 1-butyl-2-methylimidazole, 1-butyl-4-methylimidazole, 1-butyl-5-methylimidazole, 1-butyl-2,4-dimethylimidazole, 1-butyl-2,5-dimethylimidazole and 1-butyl-2,4,5-trimethylimidazole. Suitable imidazoles are available from commercial chemical suppliers such as, for example, Millipore Sigma and / or synthesized by conventional methods.

[0079] Film composition

[0080] The film composition comprises the following components:

[0081] (a) A copolymer comprising the following divalent monomer units:

[0082] (i) and

[0083] (ii) as well as

[0084] (b) an ionic organosilane according to the present disclosure, wherein R 1 To R 6 , X and n are as defined previously.

[0085] Component (a) can be prepared by reacting a copolymer of styrene and p-chloromethylstyrene (or p-bromomethylstyrene) with a suitable group R 5 and R 6 The chloromethyl groups can be prepared by reaction of functionalized imidazoles, for example in the same manner as in the case of the above-mentioned ionic organosilanes. The conversion of the chloromethyl groups can be partial or substantially complete.

[0086] Parachloromethylstyrene and styrene are commercially available or can be synthesized by conventional methods and can be copolymerized in essentially any ratio using conventional free radical polymerization techniques (e.g., using a thermal free radical initiator such as a peroxide). Alternatively, many copolymers of styrene and parachloromethylstyrene (also known as 4-vinylbenzyl chloride) are available from commercial chemical suppliers. The corresponding molar ratio of monomer unit (i) to monomer unit (ii) is 60:40 (i.e., 1.5 to 1) to 75:25, or 60:40 to 70:30, preferably 65:35 to 70:30.

[0087] membrane

[0088] The membrane composition can be formed into a membrane by any suitable technique (including, for example, solvent casting). For example, any membrane thickness of about one millimeter at most can be made in this way. Other methods and membrane thicknesses can also be used. Membranes according to the present disclosure can be used as anion exchange membranes such as electrolyzers, electrodialysis cells, fuel cells, and flow batteries.

[0089] Selected Embodiments of the Disclosure

[0090] In a first aspect, the present disclosure provides a dihaloorganosilane represented by the formula:

[0091]

[0092] Among them, X, Ar 1 , R 1 , R 2 , R 3 , R 4 and n are as defined previously.

[0093] In a second embodiment, the present disclosure provides a dihalogenated organosilane according to the first embodiment, wherein each R 1 independently represents an alkylene group having 2 or 3 carbon atoms.

[0094] In a third embodiment, the present disclosure provides a dihalogenated organosilane according to the first embodiment or the second embodiment, wherein each R 3 independently represents an alkylene group having 2 to 4 carbon atoms.

[0095] In a fourth embodiment, the present disclosure provides a dihalogenoorganosilane according to any one of the first to third embodiments, each R 4 independently represents an alkylene group having 6 to 10 carbon atoms.

[0096] In a fifth embodiment, the present disclosure provides a dihaloorganosilane according to any one of the first to fourth embodiments, wherein n=0.

[0097] In a sixth embodiment, the present disclosure provides a dihaloorganosilane according to any one of the first to fifth embodiments, wherein n=1.

[0098] In a seventh embodiment, the present disclosure provides an ionic organosilane represented by the formula:

[0099]

[0100] Among them, X, Ar 1 , R 1 , R 2 , R 3 , R 4 , R 5 , R 6 and n are as defined previously.

[0101] In an eighth embodiment, the present disclosure provides an ionic organosilane according to the seventh embodiment, wherein each R 1 independently represents an alkylene group having 2 or 3 carbon atoms.

[0102] In a ninth embodiment, the present disclosure provides an ionic organosilane according to the seventh embodiment or the eighth embodiment, wherein each R 3 independently represents an alkylene group having 2 to 4 carbon atoms.

[0103] In a tenth embodiment, the present disclosure provides an ionic organosilane according to any one of the seventh to ninth embodiments, wherein each R 4 independently represents an alkylene group having 6 to 10 carbon atoms.

[0104] In an eleventh embodiment, the present disclosure provides an ionic organosilane according to any one of the seventh to tenth embodiments, wherein n=0.

[0105] In a twelfth embodiment, the present disclosure provides an ionic organosilane according to any one of the seventh to tenth embodiments, wherein n=1.

[0106] In a thirteenth embodiment, the present disclosure provides a film composition comprising the following components:

[0107] (a) A copolymer comprising the following divalent monomer units:

[0108] (i) and

[0109] (ii)

[0110] in:

[0111] R 5 represents H or methyl;

[0112] R 6 represents an alkyl group having 1 to 4 carbon atoms, or an allyl group; and

[0113] X represents Cl, Br or I, and

[0114] wherein monomer unit (i) and monomer unit (ii) are present in a respective molar ratio of 1.5:1 to 3:1; and

[0115] (b) an ionic organosilane compound represented by the following formula:

[0116]

[0117] in:

[0118] Each Ar 1 independently represents a benzylidene group optionally substituted by 1 to 4 alkyl groups selected from methyl or ethyl;

[0119] Each R 1 independently represents an alkylene group having 2 to 18 carbon atoms;

[0120] Each R 2 independently represents a methyl group or an ethyl group;

[0121] Each R 3 independently represents an alkylene group having 1 to 18 carbon atoms;

[0122] Each R 4 independently represents an alkylene group having 2 to 18 carbon atoms;

[0123] Each R 5 independently represents H or methyl;

[0124] Each R 6 independently represents an alkyl group having 1 to 4 carbon atoms, or an allyl group; and

[0125] n is an integer ranging from 0 to 5, inclusive; and

[0126] Component (a) and component (b) are present in a respective weight ratio of 99.5:0.5 to 98:2.

[0127] In a fourteenth embodiment, the present disclosure provides a film composition according to the thirteenth embodiment, wherein each R 1 independently represents an alkylene group having 2 or 3 carbon atoms.

[0128] In a fifteenth embodiment, the present disclosure provides a film composition according to the thirteenth embodiment or the fourteenth embodiment, wherein each R 3 independently represents an alkylene group having 2 to 4 carbon atoms.

[0129] In a sixteenth embodiment, the present disclosure provides a film composition according to the thirteenth to fifteenth embodiments, wherein each R 4 independently represents an alkylene group having 6 to 10 carbon atoms.

[0130] In a seventeenth embodiment, the present disclosure provides a film composition according to any one of the thirteenth to sixteenth embodiments, wherein n=0.

[0131] In an eighteenth embodiment, the present disclosure provides a film composition according to any one of the thirteenth to sixteenth embodiments, wherein n=1.

[0132] In a nineteenth embodiment, the present disclosure provides a film composition according to any one of the thirteenth to eighteenth embodiments, wherein R 6 represents an alkyl group having 1 to 4 carbon atoms.

[0133] In a twentieth embodiment, the present disclosure provides an ionic organosilane according to any one of the thirteenth to nineteenth embodiments, wherein R 6 It represents allyl.

[0134] In a twenty-first embodiment, the present disclosure provides a film comprising the film composition according to any one of the thirteenth to twentieth embodiments.

[0135] Objects and advantages of this disclosure are further illustrated by the following non-limiting examples, but the particular materials and amounts thereof recited in these examples, as well as other conditions and details, should not be construed to unduly limit this disclosure.

[0136] Example

[0137] Unless otherwise stated, all parts, percentages, ratios, etc. in the examples and the rest of the specification are by weight. Table 1 below reports the materials used in the examples.

[0138] Table 1

[0139]

[0140] Preparation of organosilane OS1 :

[0141]

[0142] Platinum divinyltetramethyldisiloxane complex (1 drop, 2.1 wt%-2.4 wt% Pt in xylene) was added to a solution of 1,1,4,4-tetramethyl-1,4-disilylbutane (4.40 g, 0.030 mol) and vinylbenzyl chloride (9.17 g, 0.060 mol) in toluene (60 mL). After the initial exotherm, the reaction mixture was stirred at room temperature for 3 days, and the toluene was removed in vacuo to give the product shown above as a colorless oil.

[0143] Preparation of organosilane OS2 :

[0144]

[0145] Platinum divinyltetramethyldisiloxane complex (1 drop, 2.1 wt%-2.4 wt% Pt in xylene) was added to a solution of 1,1,4,4-tetramethyl-1,4-disilylbutane (8.80 g, 0.060 mol), 1,7-octadiene (3.30 g, 0.0.03 mol) and vinylbenzyl chloride (9.17 g, 0.060 mol) in toluene (40 mL). After the initial exotherm, the reaction mixture was stirred at room temperature for 3 days, and the toluene was removed in vacuo to give the unpurified product as a viscous liquid.

[0146] Synthesis of membrane composition E1 :

[0147] 10 g of styrene / vinyl benzyl chloride copolymer (S / VBC, composition: 63.1 mol% styrene, 36.9 mol% VBC, M) was added to a 250 mL three-necked round-bottom flask equipped with a magnetic stirrer, a heating mantle, a thermocouple, and a nitrogen blanket inlet. n =55kg / mol-60kg / mol, polydispersity of 1.3), tetramethylimidazole (3.27g, 26.3mmol), organosilane OS1 (0.15g, 0.664mmol benzyl chloride, 1.1% by weight of total solids) (a total of 0.85 equivalents of base to 1 equivalent of benzyl chloride (contributed by copolymer and carbosilane)) and 1-methoxy-2-propanol (26.8g). The mixture was stirred at 70°C for 48 hours to obtain a light yellow solution.

[0148] Synthesis of membrane composition E2 :

[0149] 10 g of styrene / vinyl benzyl chloride copolymer (S / VBC, composition: 63.1 mol% styrene, 36.9 mol% VBC, M) was added to a 250 mL three-necked round-bottom flask equipped with a magnetic stirrer, a heating mantle, a thermocouple, and a nitrogen blanket inlet. n=55kg / mol-60kg / mol, polydispersity of 1.3), tetramethylimidazole (3.33g, 26.8mmol), organosilane OS1 (0.29g, 1.288mmol benzyl chloride, 2.1% by weight of total solids) (a total of 0.85 equivalents of base to 1 equivalent of benzyl chloride (contributed by copolymer and carbosilane)) and 1-methoxy-2-propanol (26.8g). The mixture was stirred at 70°C for 48 hours to obtain a light yellow solution.

[0150] Synthesis of membrane composition E3 :

[0151] 10 g of styrene / vinyl benzyl chloride copolymer (S / VBC, composition: 63.1 mol% styrene, 36.9 mol% VBC, M) was added to a 250 mL three-necked round-bottom flask equipped with a magnetic stirrer, a heating mantle, a thermocouple, and a nitrogen blanket inlet. n =55kg / mol-60kg / mol, polydispersity of 1.3), tetramethylimidazole (3.24g, 26.1mmol), organosilane OS2 (0.15g, 0.424mmol benzyl chloride, 1.1% by weight of total solids) (a total of 0.85 equivalents of base to 1 equivalent of benzyl chloride (contributed by copolymer and carbosilane)) and 1-methoxy-2-propanol (26.8g). The mixture was stirred at 70°C for 48 hours to obtain a light yellow solution.

[0152] Synthesis of membrane composition CE1

[0153] 10 g of styrene / vinyl benzyl chloride copolymer (S / VBC, composition: 63.1 mol% styrene, 36.9 mol% VBC, M) was added to a 250 mL three-necked round-bottom flask equipped with a magnetic stirrer, a heating mantle, a thermocouple, and a nitrogen blanket inlet. n =55kg / mol-60kg / mol, polydispersity of 1.3), tetramethylimidazole (3.19g, 25.7mmol) (a total of 0.85 equivalents of base to 1 equivalent of benzyl chloride (contributed only by the copolymer)) and 1-methoxy-2-propanol (26.8g). The mixture was stirred at 70°C for 48 hours to obtain a light yellow solution.

[0154] Synthesis of membrane composition CE2

[0155] 10 g of styrene / vinyl benzyl chloride copolymer (S / VBC, composition: 63.1 mol% styrene, 36.9 mol% VBC, M) was added to a 250 mL three-necked round-bottom flask equipped with a magnetic stirrer, a heating mantle, a thermocouple, and a nitrogen blanket inlet. n=55kg / mol-60kg / mol, polydispersity of 1.3), tetramethyl imidazole (3.33g, 26.8mmol), control organosilane 1,1,4,4-tetramethyl-1,4-disilylbutane (0.15g, 1.1% by weight of total solids, no benzyl chloride functional group) mixture (total 0.88 equivalents of base to 1 equivalent of benzyl chloride (contributed only by the copolymer)) and 1-methoxy-2-propanol (26.8g). The mixture was stirred at 70°C for 48 hours to obtain a light yellow solution.

[0156] Synthesis of membrane composition CE3

[0157] 10 g of styrene / vinyl benzyl chloride copolymer (S / VBC, composition: 63.1 mol% styrene, 36.9 mol% VBC, M) was added to a 250 mL three-necked round-bottom flask equipped with a magnetic stirrer, a heating mantle, a thermocouple, and a nitrogen blanket inlet. n =55kg / mol-60kg / mol, polydispersity of 1.3), tetramethyl imidazole (3.33g, 26.8mmol), control organosilane 1,4,4-tetramethyl-1,4-disilylbutane (0.29g, 2.1% by weight of total solids, no benzyl chloride functional group) mixture (total 0.88 equivalents of base to 1 equivalent of benzyl chloride (contributed only by the copolymer)) and 1-methoxy-2-propanol (26.8g). The mixture was stirred at 70°C for 48 hours to obtain a light yellow solution.

[0158] Examples E4-E5 and Comparative Examples CE4-CE5

[0159] Membrane polymers composed of dimethylimidazole (E4, CE4) and N-allylimidazole (E5, CE5) were synthesized following corresponding procedures similar to those described for tetramethylimidazole (E1 and CE1).

[0160] Membrane preparation and characterization

[0161] Membrane preparation

[0162] Films were prepared by coating a 30-33 wt% solid ionomer solution on a release liner having a polyethylene terephthalate backing coated with an acrylic release layer as described in U.S. Pat. No. 7,816,477 (Suwa et al.) (as reported in Table 2). The films were coated using a BYK BYKO-driven automatic coater (Gardco) set at a speed of 1 inch / second (2.54 cm / sec) and a notched bar coater with a gap of 10 mils (0.01 inches, 0.254 mm), and then dried in a forced air oven at 80° C. for 30 minutes. The dry coating thickness was measured to be in the range of 45 microns to 52 microns.

[0163] Table 2

[0164]

[0165] Tensile testing of membranes

[0166] The tensile stress-strain properties of the wet films were examined at a constant strain rate of 2 mm / s. The samples were removed from the release liner and soaked in a 1 M aqueous KOH solution for 24 hours at room temperature, washed thoroughly with deionized water, cut into 1.00 cm x 4.00 cm strips, and tested in a fully hydrated state using a TAXTPlus texture analyzer (Texture Technologies, Hamilton, MA). Four strips were cut and tensile tested for each film. The average of four replicates is reported in Table 3. The dimensions (x, y, z) of the films were measured before and after the alkali soak in order to calculate the swelling values.

[0167] The results show that 1 wt% loading of ionomeric organosilane OS1 is optimal for increasing elongation at break and toughness of TMIM, DMIM and allyl IM membrane polymers (E1, E4, E5) relative to membrane polymers with similar ion exchange capacity (IEC) without carrying carbosilane (CE1, CE4, CE5). The results also show that 1 wt% loading of ionomeric organosilane OS2 increases elongation at break and toughness of TMIM membrane polymer (E3) relative to membrane polymers with similar ion exchange capacity (IEC) without carrying carbosilane (CE1). 2 wt% loading of ionomeric organosilane OS1 does not impart the same beneficial effect at comparable IEC (E2) nor does it impart the same beneficial effect to the non-ionomeric control carbosilane at comparable IEC and wt% loading (CE2, CE3).

[0168]

[0169] Conductivity test of membrane

[0170] Ionic conductivity was measured using a 4-probe BekkTech BT-110 conductivity fixture (Scribner Associates, Inc., Southern Pines, NC) and a VMP3 multichannel potentiostat (Bio-Logic Science Instruments, Seyssinet-Pariset, France). Dried membrane samples (1.40 cm x 4.00 cm) in chloride form were assembled under two platinum wires, and the fixture was immersed in 18 megohm deionized water for 2 hours to hydrate and swell the membrane prior to measurement. Current-voltage curves were recorded by applying a linear voltage sweep from open circuit voltage (OCV) first to 0.3 V, then to -0.3 V, and finally back to OCV at a scan rate of 10 mV / sec. The ionic conductivity was calculated from the slope of the resulting current-voltage curve using the measured dry film dimensions and thickness and an ionic conductivity clamping constant of 0.425 cm.

[0171] Table 4

[0172] membrane <![CDATA[CL - Conductivity in form, mS / cm]]> E1 20.6 E2 --- E3 --- CE1 20.3 CE2 --- CE3 --- E4 20.5 CE4 18.5 E5 19.0 CE5 17.1

[0173] The foregoing description, which is given to enable one of ordinary skill in the art to practice the present disclosure protected by the claims, should not be construed as limiting the scope of the present disclosure, which is defined by the claims and all equivalents thereof.

Claims

1. A film composition comprising the following components: (a) A copolymer comprising the following divalent monomer units: (i) and (ii) in: R 5 represents H or methyl; R 6 represents an alkyl group having 1 to 4 carbon atoms, or an allyl group; and X represents Cl, Br or I, and wherein monomer unit (i) and monomer unit (ii) are present in a respective molar ratio of 1.5:1 to 3:1; and (b) an ionic organosilane compound represented by the following formula: in: Each Ar 1 independently represents a benzylidene group optionally substituted by 1 to 4 alkyl groups selected from methyl or ethyl; Each R 1 independently represents an alkylene group having 2 to 18 carbon atoms; Each R 2 independently represents a methyl group or an ethyl group; Each R 3 independently represents an alkylene group having 1 to 18 carbon atoms; Each R 4 independently represents an alkylene group having 2 to 18 carbon atoms; and n is an integer ranging from 0 to 5, inclusive; and Component (a) and component (b) are present in a respective weight ratio of 99.5:0.5 to 98:

2.

2. The film composition according to claim 1, wherein each R 1 independently represents an alkylene group having 2 or 3 carbon atoms.

3. The film composition according to claim 1, wherein each R 3 independently represents an alkylene group having 2 to 4 carbon atoms.

4. The film composition according to claim 1, wherein each R 4 independently represents an alkylene group having 6 to 10 carbon atoms. The film composition according to claim 1 , wherein n=0. The film composition according to claim 1 , wherein n=1.

7. The film composition according to claim 1, wherein R 6 represents an alkyl group having 1 to 4 carbon atoms.

8. The film composition according to claim 1, wherein R 6 It represents allyl.

9. A film comprising the film composition according to claim 1.

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