Spacer frame for use in an alkaline electrolyzer system

Abstract

An alkaline electrolyzer system is provided that includes an electrochemical cell in proximity to a spacer frame. The spacer frame contains a polymer composition that includes a polymer matrix containing at least one polyarylene sulfide.

Description

Technical Field

[0001] Related Applications

[0001] This application claims priority based on, and hereby claims priority to, U.S. Provisional Patent Application No. 63 / 345,924, filed May 26, 2022, which is incorporated herein by reference.

Background Art

[0002]

[0002] Alkaline electrolyzers utilize electrical energy to facilitate chemical reactions. A fuel, such as alkaline water, is supplied to an electrochemical cell, and products (hydrogen and oxygen) are removed from the electrochemical cell. An alkaline electrolyzer system generally includes a stack of individual cells that are electrically and fluidly connected to each other. Each cell includes several components, electrodes, separators, etc., which are specifically oriented and held relative to each other to enable the required flow rates and electrical connections. To maintain the desired orientation, spacers in the form of spacer plates or frames are utilized around the active components. Conventional spacers are made from metals or certain polymers, mainly polyphenylsulfone materials. The material can be molded into the desired shape for the spacer, but it is relatively difficult and costly to mold into the high-precision shapes required to meet the desired specifications. Other materials have been investigated, but the desired material must also be able to withstand the alkaline environment of the cell. Therefore, there is a current need for spacers that can be more easily introduced into alkaline electrolyzer systems.

Summary of the Invention

Means for Solving the Problems

[0003] According to one embodiment of the present invention, an alkaline electrolyzer system is disclosed that includes an electrochemical cell proximate to a spacer frame. The spacer frame contains a polymer composition including a polymer matrix containing from about 40 wt% to about 95 wt% of at least one polyarylene sulfide and from about 5 wt% to about 60 wt% of at least one filler disposed within the polymer matrix.

[0004] According to another embodiment of the present invention, an alkaline electrolyzer system is disclosed that includes an electrochemical cell proximate to a spacer frame that defines channels with curvilinear walls. The curvilinear walls contain a polymer composition including a polymer matrix containing at least one polyarylene sulfide.

[0005] Other features and aspects of the present invention are described in more detail below.

[0006] The complete and authorized disclosure of the present invention, including the best mode for those skilled in the art, will be described more specifically in the remainder of this specification, including reference to the accompanying drawings.

Brief Description of the Drawings

[0006]

Figure 1

[0007] It is a schematic diagram of one embodiment of an alkaline electrochemical reactor cell.

Figure 2

[0008] It is a schematic diagram of one embodiment of an alkaline electrochemical reactor cell.

Figure 3

[0009] It is a schematic diagram of one embodiment of an alkaline electrochemical reactor cell stack.

Figure 4

[0010] It is a schematic diagram of one embodiment of an alkaline electrochemical reactor cell.

Figure 5

[0011] It is a schematic diagram of one embodiment of an alkaline electrolyzer system.

Mode for Carrying Out the Invention

[0007]

[0012] The repeated use of reference characters in this specification and drawings is intended to represent the same or similar features or elements of the present invention.

[0013] Those skilled in the art will understand that this description is only of exemplary embodiments and does not limit the broader aspects of the present invention.

[0008]

[0014] Generally speaking, the present invention is directed to an alkaline electrolyzer system including at least one spacer frame for an alkaline electrolyzer. The spacer frame may surround any component of the electrochemical cell or stack of the alkaline electrolyzer. For example, without limitation, the spacer frame can hold electrodes, separators, bipolar plates, current collectors, or diffusion layers. The spacer frame can also easily provide a spacing between other components of the electrochemical cell or stack of the alkaline electrolyzer. The spacer frame can be in contact with the fluid being conveyed, such as an alkaline feed material to the alkaline electrolyzer or a product from the alkaline electrolyzer, but in the case of a spacer plate, for example, it is not necessary to be in direct contact with the fluid.

[0009]

[0015] Nevertheless, at least some of the spacer frames (if not the entire frame) contain a polymer composition comprising at least one polyarylene sulfide. In certain embodiments, the polymer composition can include a polymer matrix that, in combination with one or more fillers disposed within the polymer matrix, can include at least one polyarylene sulfide. By way of example, the polymer matrix can include from about 40 wt% to about 95 wt% of at least one polyarylene sulfide and from about 5 wt% to about 60 wt% of at least one filler in the polymer matrix. The spacer frame can define channels (e.g., channels for conveying fluid to or from components held by the spacer frame) in the polymer composition. By selectively controlling the specific properties of the polyarylene sulfide as well as the properties and concentrations of other optional components in the composition, it has been discovered that the resulting composition can exhibit a unique combination of properties suitable for the spacer frame. For example, the polymer composition, when measured by a capillary rheometer according to ISO 11443:2021 at a temperature of about 310 °C and a shear rate of 1200 s -1 −1, can exhibit a relatively low melt viscosity, e.g., about 2,000 Pa·s or less, in some embodiments about 1,000 Pa·s or less, in some embodiments about 800 Pa·s or less, and in some embodiments about 50 to about 600 Pa·s.

[0010]

[0016] Due to the relatively low melt viscosity, relatively high molecular weight polyarylene sulfides can also be used without much difficulty. For example, when such high molecular weight polyarylene sulfides are determined using the following gel permeation chromatography, they have a number average molecular weight of about 14,000 grams / mole ("g / mol") or more, in some embodiments about 15,000 g / mol or more, and in some embodiments about 16,000 g / mol to about 60,000 g / mol, as well as a weight average molecular weight of about 35,000 g / mol or more, in some embodiments about 50,000 g / mol or more, and in some embodiments about 60,000 g / mol to about 90,000 g / mol. One benefit of using such high molecular weight polymers is generally having a low chlorine content. In this regard, the resulting polymer composition can have a low chlorine content of about 1,200 ppm or less, in some embodiments about 900 ppm or less, in some embodiments 0 to about 800 ppm, and in some embodiments about 1 to about 500 ppm, etc.

[0011]

[0017] Despite having a low melt viscosity, the polymer composition can still maintain a high level of impact strength, resulting in enhanced flexibility in the resulting spacer frame. For example, the polymer composition, when measured at a temperature of 23°C in accordance with ISO test number 179-1:2010, has a notched Charpy impact strength of about 20 kJ / m 2 or more, in some embodiments about 40 to about 150 kJ / m 2 and in some embodiments about 55 to about 100 kJ / m 2 . Advantageously, the polymer product has a high heat resistance and can thus exhibit good impact strength at both high and low temperatures. For example, the polymer product, when measured at a temperature of -30°C in accordance with ISO test number 179-1:2010, has a notched Charpy impact strength of about 10 kJ / m 2 or more, in some embodiments about 20 to about 100 kJ / m 2 and in some embodiments about 30 to about 80 kJ / m 2 .

[0012]

[0018] Tensile and flexural mechanical properties can also be good. For example, the composition can have a tensile strength of about 20 MPa or more, in some embodiments about 25 to about 200 MPa, in some embodiments about 30 to about 150 MPa, in some embodiments about 35 to about 100 MPa; a tensile fracture strain of about 20% or more, in some embodiments about 25% or more, in some embodiments about 30% or more, in some embodiments about 35% to about 100%; and / or a tensile modulus of about 10,000 MPa or less, in some embodiments about 500 MPa to about 8,000 MPa, in some embodiments about 1,000 MPa to about 6,000 MPa, in some embodiments about 1,500 MPa to about 5,000 MPa. The tensile properties can be determined at a temperature of 23 °C in accordance with ISO test number 527:2019. The composition can also have a flexural strength of about 20 MPa or more, in some embodiments about 25 to about 200 MPa, in some embodiments about 30 to about 150 MPa, in some embodiments about 35 to about 100 MPa and / or a flexural modulus of about 10,000 MPa or less, in some embodiments about 500 MPa to about 8,000 MPa, in some embodiments about 1,000 MPa to about 6,000 MPa, in some embodiments about 1,500 MPa to about 5,000 MPa. The flexural properties can be determined at a temperature of 23 °C in accordance with ISO test number 178:2019.

[0013]

[0019] The polymer composition can generally also be resistant to the penetration of fluids such as hydrogen, oxygen, water, liquid electrolytes, liquid / gas mixtures, etc., which may potentially come into contact with the spacer frame. For example, the polymer composition can have a hydrogen permeation rate of about 30 ml / m 2 *day or less, in some embodiments about 20 ml / m 2 *day or less, in some embodiments about 10 ml / m 2 *day or less, in some embodiments about 0.1 to about 5 ml / m 2 *day, as measured at a temperature of about 23 °C and a pressure difference of 1 atm in accordance with ASTM D1434-82(2015)(volumetric method). The polymer composition can similarly have a water vapor transmission rate of about 30 ml / m 2 *day or less, in some embodiments about 20 ml / m2 *per day or less, in some embodiments about 10 ml / m 2 *per day or less, in some embodiments about 0.1 to about 5 ml / m 2 *per day. The oxygen transmission rate can be shown. The polymer composition, after contact with n - hexane (7 hours), acetone (7 hours), and / or deionized water (24 hours), has low levels of extractable contaminants, for example about 2 mg / cm 2 or less, in some embodiments about 1.5 mg / cm 2 or less, in some embodiments about 0.5 mg / cm 2 or less of extractable compounds, and can be essentially relatively pure.

[0014]

[0020] Due to the relatively low melt viscosity and mechanical properties of the polymer composition, the composition is particularly well-suited for spacer frames with small dimensional tolerances. The spacer, for example, generally has at least one fine dimension (e.g., thickness, width, height, etc.), such as about 1,000 micrometers or less, in some embodiments about 100 to about 500 micrometers, and in some embodiments about 200 to about 400 micrometers, and contains a shaped member (e.g., a channel wall). One such shaped member is a seal channel that can hold a seal to prevent fluid leakage from an electrolytic cell or cell stack. Another such shaped member can be a fluid channel that can direct fluid, for example, from a component held by the spacer frame to a component across the surface of the spacer frame. For example, the channel can include walls having a height of about 1,000 micrometers or less, in some embodiments about 100 to about 450 micrometers, and in some embodiments about 200 to about 400 micrometers. Conventionally, it has often been difficult to adequately fill the mold of a channel with such small walls with a polymer composition. However, due to its unique properties, the polymer composition of the present invention is particularly well-suited for forming the walls of the channel. In certain embodiments, the channel can have a curved wall that defines a radius of curvature along the length of the wall in a circular or helical pattern. A smooth curved wall can result in an improved seal in the case of a seal channel, and in the case of a fluid channel, a smooth curved wall can result in an improved flow field for the fluid conveyed within the channel.

[0015]

[0021] Various embodiments of the present invention will now be described in more detail hereinafter. I. Polymer Composition A. Polymer Matrix

[0022] The polymer matrix typically occupies from about 40 wt% to 100 wt% of the polymer composition, in some embodiments from about 40 wt% to about 95 wt%, in some embodiments from about 50 wt% to about 95 wt%, and in some embodiments from about 60 wt% to about 90 wt%. In certain embodiments, no filler may be added to the polymer composition, and thus the polymer matrix itself occupies 100 wt% of the composition. In other embodiments, the polymer composition may be filled with at least one filler disposed within the polymer matrix in an amount of from about 5 wt% to about 60 wt% of the polymer composition, in some embodiments from about 10 wt% to about 55 wt%, and in some embodiments from about 15 wt% to about 50 wt%. Whether or not the composition is filled, the polymer matrix contains at least one polyarylene sulfide. In certain embodiments, the polyarylene sulfide may occupy the entire polymer matrix. In other cases, the polyarylene sulfide may occupy only a very small portion of the matrix. However, in such embodiments, the polyarylene sulfide typically occupies at least about 50 wt% of the polymer matrix, in some embodiments at least about 65 wt% of the polymer matrix, and in some embodiments from about 75 wt% to about 99 wt% of the polymer matrix.

[0016]

[0023] The polyarylene sulfide used in the polymer matrix generally has repeating units of the following formula: -[(Ar 1 ) n -X] m -[(Ar 2 ) i -Y] j -[(Ar 3 ) k -Z] l -[(Ar 4 ) o -W] p - (wherein Ar 1 、Ar 2 、Ar 3 、and Ar 4is, independently, an arylene unit having 6 to 18 carbon atoms, W, X, Y, and Z are, independently, -SO 2 -, -S-, -SO-, -CO-, -O-, -C(O)O- or an alkylene or alkylidene group having 1 to 6 carbon atoms, wherein at least one of the linking groups is -S-, n, m, i, j, k, l, o, and p are, independently, 0, 1, 2, 3, or 4, provided that the sum thereof is 2 or more).

[0017]

[0024] The arylene unit Ar 1 , Ar 2 , Ar 3 , and Ar 4 may be optionally substituted or unsubstituted. Advantageous arylene units are phenylene, biphenylene, naphthalene, anthracene and phenanthrene. The polyarylene sulfide typically contains more than about 30 mol%, more than about 50 mol%, or more than about 70 mol% of arylene sulfide (-S-) units. For example, the polyarylene sulfide may contain at least 85 mol% of sulfide bonds directly bonded to two aromatic rings. In a particular embodiment, the polyarylene sulfide is a polyphenylene sulfide as defined herein that contains as a component thereof a phenylene sulfide structure -(C 6 H 4 -S) n -(wherein n is an integer of 1 or more).

[0018]

[0025] Synthesis techniques that can be used in making polyarylene sulfide are generally known in the art. By way of example, the process for generating polyarylene sulfide may include the step of reacting a substance that provides hydrosulfide ions (e.g., an alkali metal sulfide) with a dihaloaromatic compound in an organic amide solvent. The alkali metal sulfide may be, for example, lithium sulfide, sodium sulfide, potassium sulfide, rubidium sulfide, cesium sulfide or a mixture thereof. When the alkali metal sulfide is a hydrate or an aqueous mixture, prior to the polymerization reaction, the alkali metal sulfide may be treated by a dehydration process. The alkali metal sulfide can also be generated in situ. In addition, a small amount of an alkali metal hydroxide can be included in the reaction to remove or react with impurities such as alkali metal polysulfide or alkali metal thiosulfate that may be present in a very small amount together with the alkali metal sulfide (in order to change the impurities into harmless substances).

[0019]

[0026] The dihaloaromatic compound may be, without limitation, o-dichlorobenzene, m-dichlorobenzene, p-dichlorobenzene, dihalotoluene, dihalonaphthalene, methoxy-dichlorobenzene, dihalobiphenyl, dihalobenzoic acid, dihalodiphenyl ether, dihalodiphenyl sulfone, dihalodiphenyl sulfoxide or dihalodiphenyl ketone. The dihaloaromatic compounds may be used singly or in any combination thereof. Specific exemplary dihaloaromatic compounds include, without limitation, p-dichlorobenzene, m-dichlorobenzene, o-dichlorobenzene, 2,5-dichlorotoluene, 1,4-dibromobenzene, 1,4-dichloronaphthalene, 1-methoxy-2,5-dichlorobenzene, 4,4'-dichlorobiphenyl, 3,5-dichlorobenzoic acid, 4,4'-dichlorodiphenyl ether, 4,4'-dichlorodiphenyl sulfone, 4,4'-dichlorodiphenyl sulfoxide, and 4,4'-dichlorodiphenyl ketone. The halogen atom may be fluorine, chlorine, bromine or iodine, and the two halogen atoms in the same dihaloaromatic compound may be identical to or different from each other. In one embodiment, o-dichlorobenzene, m-dichlorobenzene, p-dichlorobenzene, or a mixture of two or more of these compounds is used as the dihaloaromatic compound. As is known in the art, a monohalo compound (which does not necessarily have to be an aromatic compound) can also be used in combination with the dihaloaromatic compound to form the end groups of the polyarylene sulfide or to adjust the polymerization reaction and / or the molecular weight of the polyarylene sulfide.

[0020]

[0027] The polyarylene sulfide may be a homopolymer or a copolymer. For example, a selective combination of dihaloaromatic compounds can produce a polyarylene sulfide copolymer containing two or more different units. For example, when p-dichlorobenzene is used in combination with m-dichlorobenzene or 4,4'-dichlorodiphenyl sulfone, the following formula:

[0021]

Chemical formula

[0022] Segments having the structure of and the following formula:

[0023]

Chem.

[0024] Segments having the structure of or the following formula:

[0025]

Chem.

[0026] A polyarylene sulfide copolymer containing segments having the structure of can be formed.

[0028] The polyarylene sulfide may be linear, semi-linear, branched or cross-linked. Linear polyarylene sulfide typically contains 80 mol% or more of the repeating unit -(Ar-S)-. Such linear polymers may also contain a small amount of branched or cross-linked units, but the amount of branched or cross-linked units is typically less than about 1 mol% of the total monomer units of the polyarylene sulfide. The linear polyarylene sulfide polymer may be a random copolymer or a block copolymer containing the above repeating units. Similarly, semi-linear polyarylene sulfide may also have a cross-linked or branched structure introduced into a small amount of polymer of one or more monomers having three or more reactive functional groups. As an example, the monomer components used in forming semi-linear polyarylene sulfide contain to some extent polyhaloaromatic compounds having two or more halogen substituents per molecule that can be utilized in preparing branched polymers. Such monomers have the formula R’X n(Wherein each X is selected from chlorine, bromine, and iodine, n is an integer from 3 to 6, R' is a polyvalent aromatic group of valence n that may have up to about 4 methyl substituents, and the total number of carbon atoms in R' is in the range of 6 to about 16) can be represented by. Examples of some polyhaloaromatic compounds substituted with more than two halogens per molecule that can be used in forming semi-linear polyarylene sulfide include 1,2,3-trichlorobenzene, 1,2,4-trichlorobenzene, 1,3-dichloro-5-bromobenzene, 1,2,4-triiodobenzene, 1,2,3,5-tetrabromobenzene, hexachlorobenzene, 1,3,5-trichloro-2,4,6-trimethylbenzene, 2,2',4,4'-tetrachlorobiphenyl, 2,2',5,5'-tetra-iodobiphenyl, 2,2',6,6'-tetrabromo-3,3',5,5'-tetramethylbiphenyl, 1,2,3,4-tetrachloronaphthalene, 1,2,4-tribromo-6-methylnaphthalene, etc., and mixtures thereof.

[0027]

[0029] According to requirements, the polyarylene sulfide can be functionalized. As an example, a disulfide compound containing a reactive functional group (such as carboxyl, hydroxyl, amine, etc.) can react with the polyarylene sulfide. Further, the functionalization of the polyarylene sulfide can provide a binding site between any optional impact modifier and the polyarylene sulfide, which can improve the distribution of the impact modifier throughout the polyarylene sulfide and prevent phase separation. The disulfide compound can undergo a chain cleavage reaction with the polyarylene sulfide during melt processing to reduce the melt viscosity. When used, the disulfide compound typically accounts for about 0.01 wt% to about 3 wt% of the polymer composition, in some embodiments about 0.02 wt% to about 1 wt%, and in some embodiments about 0.05 to about 0.5 wt%. The ratio of the amount of the polyarylene sulfide to the amount of the disulfide compound may similarly be about 1000:1 to about 10:1, about 500:1 to about 20:1, or about 400:1 to about 30:1. Suitable disulfide compounds typically have the following formula: R 3 -S-S-R 4

[0030] In the formula, R 3 and R 4 may be the same or different and are independently hydrocarbon groups containing 1 to about 20 carbon atoms. For example, R 3 and R 4 may be alkyl, cycloalkyl, aryl, or heterocyclic groups. In certain embodiments, R 3 and R 4 are generally non-reactive functional groups such as phenyl, naphthyl, ethyl, methyl, propyl, etc. Examples of such compounds include diphenyl disulfide, naphthyl disulfide, dimethyl disulfide, diethyl disulfide, and dipropyl disulfide. R 3 and R 4 may also include reactive functional groups at the end groups of the disulfide compound. For example, R 3 and R 4At least one of them may contain a terminal carboxyl group, a hydroxyl group, a substituted or unsubstituted amino group, or a nitro group, etc. Examples of the compound include, but are not limited to, 2,2'-diaminodiphenyl disulfide, 3,3'-diaminodiphenyl disulfide, 4,4'-diaminodiphenyl disulfide, dibenzyl disulfide, dithiosalicylic acid (or 2,2'-dithiobenzoic acid), dithioglycolic acid, α,α'-dithiodilactic acid, β,β'-dithiodilactic acid, 3,3'-dithiodipyridine, 4,4'-dithiomorpholine, 2,2'-dithiobis(benzothiazole), 2,2'-dithiobis(benzimidazole), 2,2'-dithiobis(benzoxazole), 2-(4'-morpholinodithio)benzothiazole, etc., and mixtures thereof.

[0028] B. Filler

[0031] The properties of the spacer frame can be further adjusted by incorporating any of various fillers into the polymer matrix. In one embodiment, for example, at least one impact modifier may be incorporated into the polymer matrix. When used, the impact modifier typically occupies 5 to about 50 parts by weight, in some embodiments about 10 to about 45 parts by weight, and in some embodiments about 20 to about 40 parts by weight, based on 100 parts by weight of the polyarylene sulfide of the polymer matrix. For example, the impact modifier can occupy about 1 wt% to about 40 wt% of the polymer composition, in some embodiments about 5 wt% to about 35 wt%, and in some embodiments about 15 wt% to about 30 wt%.

[0029]

[0032] Examples of suitable impact modifiers include, for example, polyepoxides, polyurethanes, polybutadienes, acrylonitrile-butadiene-styrene, polyamides, block copolymers (e.g., polyether-polyamide block copolymers), and mixtures thereof. In one embodiment, an “epoxy-functionalized” olefin copolymer containing on average two or more epoxy functional groups per molecule is used. The copolymer generally contains olefinic monomer units derived from one or more α-olefins. Examples of such monomers include, for example, linear and / or branched α-olefins having 2 to 20 carbon atoms, typically 2 to 8 carbon atoms. Specific examples include ethylene, propylene, 1-butene, 3-methyl-1-butene, 3,3-dimethyl-1-butene, 1-pentene, 1-pentene having one or more methyl, ethyl or propyl substituents, 1-heptene having one or more methyl, ethyl or propyl substituents, 1-octene having one or more methyl, ethyl or propyl substituents, 1-nonene having one or more methyl, ethyl or propyl substituents, ethyl, methyl or dimethyl substituted 1-decene, 1-dodecene, and styrene. Particularly desirable α-olefin monomers are ethylene and propylene. The copolymer may also contain epoxy-functional monomer units. An example of such a unit is an epoxy-functional (meth)acrylic monomer component. As used herein, the term “(meth)acrylic” includes acrylic and methacrylic monomers, and salts or esters thereof, such as acrylate and methacrylate monomers. For example, suitable epoxy-functional (meth)acrylic monomers include, but are not limited to, those containing a 1,2-epoxy group such as glycidyl acrylate and glycidyl methacrylate. Other suitable epoxy-functional monomers include allyl glycidyl ether, glycidyl ethacrylate, and glycidyl itaconate. Other suitable monomers can also be used to assist in achieving the desired molecular weight.

[0030]

[0033] Of course, the copolymer may also contain other monomer units known in the art. For example, other suitable monomers may include non-epoxy functional (meth)acrylic monomers. Examples of such (meth)acrylic monomers include methyl acrylate, ethyl acrylate, n-propyl acrylate, i-propyl acrylate, n-butyl acrylate, s-butyl acrylate, i-butyl acrylate, t-butyl acrylate, n-amyl acrylate, i-amyl acrylate, isobornyl acrylate, n-hexyl acrylate, 2-ethylbutyl acrylate, 2-ethylhexyl acrylate, n-octyl acrylate, n-decyl acrylate, methylcyclohexyl acrylate, cyclopentyl acrylate, cyclohexyl acrylate, methyl methacrylate, ethyl methacrylate, 2-hydroxyethyl methacrylate, n-propyl methacrylate, n-butyl methacrylate, i-propyl methacrylate, i-butyl methacrylate, n-amyl methacrylate, n-hexyl methacrylate, i-amyl methacrylate, s-butyl methacrylate, t-butyl methacrylate, 2-ethylbutyl methacrylate, methylcyclohexyl methacrylate, cinnamyl methacrylate, crotyl methacrylate, cyclohexyl methacrylate, cyclopentyl methacrylate, 2-ethoxyethyl methacrylate, isobornyl methacrylate, etc., and combinations thereof. In a particular embodiment, for example, the copolymer may be a terpolymer formed from an epoxy functional (meth)acrylic monomer component, an α-olefin monomer component, and a non-epoxy functional (meth)acrylic monomer component. The copolymer may have, for example, the following structure:

[0031]

Chemical formula

[0032] (wherein x, y, and z are 1 or more) It may be poly(ethylene-co-butyl acrylate-co-glycidyl methacrylate) having the following structure.

[0033]

[0034] The relevant parts of the monomer components can be selected to achieve a balance between epoxy reactivity and melt flow rate. More specifically, a high epoxy monomer content can result in good reactivity with the matrix polymer, but too high a content can reduce the melt flow rate to the extent that the copolymer adversely affects the melt strength of the polymer blend. Thus, in most embodiments, the epoxy-functional (meth)acrylic monomer comprises from about 1 wt% to about 20 wt% of the copolymer, in some embodiments from about 2 wt% to about 15 wt%, and in some embodiments from about 3 wt% to about 10 wt%. Similarly, the α-olefin monomer can comprise from about 55 wt% to about 95 wt% of the copolymer, in some embodiments from about 60 wt% to about 90 wt%, and in some embodiments from about 65 wt% to about 85 wt%. Other monomer components (e.g., non-epoxy-functional (meth)acrylic monomers), when used, can comprise from about 5 wt% to about 35 wt% of the copolymer, in some embodiments from about 8 wt% to about 30 wt%, and in some embodiments from about 10 wt% to about 25 wt%. The resulting melt flow rate, measured according to ASTM D1238-13 at a load of 2.16 kg and a temperature of 190 °C, is typically from about 1 to about 30 grams per 10 minutes ("g / 10 min"), in some embodiments from about 2 to about 20 g / 10 min, and in some embodiments from about 3 to about 15 g / 10 min.

[0034]

[0035] According to requirements, additional impact modifiers may also be used in combination with epoxy-functional impact modifiers. For example, the additional impact modifier may include a block copolymer in which at least one phase is hard at room temperature but becomes fluid when heated, and the other phase is a soft rubber-like material at room temperature. As an example, the block copolymer may have an A-B or A-B-A block copolymer repeating structure, where A represents a hard segment and B is a soft segment. Non-limiting examples of impact modifiers having an A-B repeating structure include polyamide / polyether, polysulfone / polydimethylsiloxane, polyurethane / polyester, polyurethane / polyether, polyester / polyether, polycarbonate / polydimethylsiloxane, and polycarbonate / polyether. Triblock copolymers may likewise contain polystyrene as the hard segment and any of polybutadiene, polyisoprene, or polyethylene-co-butylene as the soft segment. Similarly, styrene-butadiene repeating copolymers and polystyrene / polyisoprene repeating polymers may be used. In a particular embodiment, the block copolymer may have alternating blocks of polyamide and polyether. Such materials are commercially available, for example, under the trade name PEBAX(™) from Atofina. The polyamide blocks may be derived from copolymers of diacid and diamine components or may be prepared by homopolymerization of cyclic lactams. The polyether blocks may be derived from homopolymers or copolymers of cyclic ethers such as ethylene oxide, propylene oxide, and tetrahydrofuran.

[0035]

[0036] Depending on the desire, the crosslinking system can also be used in combination with any optional impact modifier to help further improve the strength and flexibility of the composition under various different conditions. In such a situation, optionally in combination with one or more additional fillers, a crosslinked product can be formed from a crosslinkable polymer matrix containing a polyarylene sulfide, an impact modifier, and a crosslinking system. The crosslinking system, which may contain one or more crosslinking agents, when used, typically ranges from about 0.1 to about 15 parts, in some embodiments from about 0.2 to about 10 parts, in some embodiments from about 0.5 to about 5 parts, per 100 parts of the polyarylene sulfide of the polymer matrix, and from about 0.05 wt% to about 15 wt%, in some embodiments from about 0.1 wt% to about 10 wt%, in some embodiments from about 0.2 wt% to about 5 wt% of the polymer composition. By using such a crosslinking system, the compatibility and distribution of the polyarylene sulfide and the impact modifier can be significantly improved. For example, the impact modifier can be dispersed in the polymer composition in the form of discrete regions of nanoscale size. For example, the regions can have an average cross-sectional dimension of about 1 to about 1000 nanometers, in some embodiments from about 5 to about 800 nanometers, in some embodiments from about 10 to about 500 nanometers. The regions can have various different shapes such as oval, spherical, cylindrical, plate-like, tubular, etc. Such improved dispersion can result in better mechanical properties or enable the achievement of equivalent mechanical properties with a smaller amount of impact modifier.

[0036]

[0037] Any of a variety of different crosslinking agents can generally be used within the crosslinking system. In one embodiment, by way of example, the crosslinking system may include a metal carboxylate. Without intending to be limited by theory, it is believed that the metal atom in the carboxylate can act as a Lewis acid that accepts electrons from an oxygen atom located within a functional group of the impact modifier (e.g., an epoxy functional group). When reacting with the carboxylate, the functional group becomes activated and can be readily attacked at either one of the carbon atoms in the three-membered ring via a nucleophilic substitution reaction, thereby forming crosslinks between the chains of the impact modifier. The metal carboxylate is typically a metal salt of a fatty acid. The metal cation used in the salt can be various, but is typically a divalent metal such as calcium, magnesium, lead, barium, strontium, zinc, iron, cadmium, nickel, copper, tin, etc., and mixtures thereof. Zinc is particularly preferred. The fatty acid can generally be any saturated or unsaturated acid having a carbon chain length of about 8 to 22 carbon atoms, in some embodiments about 10 to about 18 carbon atoms. Optionally, the acid may be substituted. Suitable fatty acids include, for example, lauric acid, myristic acid, behenic acid, oleic acid, palmitic acid, stearic acid, ricinoleic acid, capric acid, neodecanoic acid, hydrogenated tallow fatty acid, hydroxystearic acid, fatty acid of hydrogenated castor oil, erucic acid, coconut oil fatty acid, etc., and mixtures thereof. The metal carboxylate typically accounts for about 0.05 wt% to about 5 wt% of the polymer composition, in some embodiments about 0.1 wt% to about 2 wt%, and in some embodiments about 0.2 wt% to about 1 wt%.

[0037]

[0038] The crosslinking system can also use a crosslinking agent that is "polyfunctional" to the extent of containing at least two reactive functional groups. Such a polyfunctional crosslinking agent can act as a weak nucleophile that can react with the activating functional groups (e.g., epoxy functional groups) of the impact modifier. The polyfunctional nature of such molecules enables crosslinking of two functional groups of the impact modifier and effectively acting as a curing agent. Polyfunctional crosslinking agents generally include two or more reactively functional terminal portions bonded by a bonding or non-polymer (non-repeating) bonding component. By way of example, crosslinking agents include diepoxides, polyfunctional epoxides, diisocyanates, polyisocyanates, polyhydric alcohols, water-soluble carbodiimides, diamines, diols, diaminoalkanes, polyfunctional carboxylic acids, diacid halides, and the like. Polyfunctional carboxylic acids and amines are particularly suitable. Specific examples of polyfunctional carboxylic acid crosslinking agents include, but are not limited to, isophthalic acid, terephthalic acid, phthalic acid, 1,2-di(p-carboxyphenyl)ethane, 4,4'-dicarboxydiphenyl ether, 4,4'-bisbenzoic acid, 1,4- or 1,5-naphthalenedicarboxylic acid, decahydronaphthalenedicarboxylic acid, norbornenedicarboxylic acid, bicyclooctanedicarboxylic acid, 1,4-cyclohexanedicarboxylic acid (both cis and trans), 1,4-hexylenedicarboxylic acid, adipic acid, azelaic acid, dicarboxydodecanoic acid, succinic acid, maleic acid, glutaric acid, suberic acid, azelaic acid, and sebacic acid. Corresponding dicarboxylic acid derivatives, such as carboxylic acid diesters having 1 to 4 carbon atoms in the alcohol group, carboxylic acid anhydrides, or carboxylic acid halides, can also be utilized. In certain embodiments, aromatic dicarboxylic acids, such as isophthalic acid or terephthalic acid, are particularly suitable.

[0038]

[0039] When used, the multifunctional crosslinking agent typically accounts for about 50 wt% to about 95 wt% of the crosslinking system, in some embodiments about 60 wt% to about 90 wt%, and in some embodiments about 70 wt% to about 85 wt%. On the other hand, the metal carboxylate typically accounts for about 5 wt% to about 50 wt% of the crosslinking system, in some embodiments about 10 wt% to about 40 wt%, and in some embodiments about 15 wt% to about 30 wt%. For example, the multifunctional crosslinking agent can account for about 0.1 wt% to about 10 wt% of the polymer composition, in some embodiments about 0.2 wt% to about 5 wt%, and in some embodiments about 0.5 wt% to about 3 wt%. Of course, in certain embodiments, the composition may generally not contain a multifunctional crosslinking agent, or the crosslinking system may generally not contain a metal carboxylate.

[0039]

[0040] Another suitable filler that can be included in the polymer matrix is a heat stabilizer. By way of example, the heat stabilizer may be a phosphite stabilizer such as an organic phosphite. For example, suitable phosphite stabilizers include monophosphites and diphosphites, and the diphosphites have a molecular structure that inhibits moisture absorption and / or has a relatively high spiro isomer content. By way of example, diphosphite stabilizers having a spiro isomer content of more than 90%, such as more than 95%, such as more than 98% can be selected. Specific examples of such diphosphite stabilizers include, for example, bis(2,4-dicumylphenyl)pentaerythritol diphosphite, bis(2,4-di-t-butylphenyl)pentaerythritol diphosphite, distearyl pentaerythritol diphosphite, mixtures thereof, and the like. When used, the heat stabilizer typically accounts for about 0.1 wt% to about 3 wt% of the composition, and in some embodiments about 0.2 wt% to about 2 wt%.

[0040]

[0041] Inorganic fibers can be used, for example, in an amount of about wt% to about 50 wt% of the polymer composition, in some embodiments about 2 wt% to about 40 wt%, and in some embodiments about 5 wt% to about 30 wt%. Various different types of inorganic fibers, such as glass; nesosilicates, sorosilicates, inosilicates (for example, calcium inosilicate such as wollastonite; calcium magnesium inosilicate such as tremolite; calcium magnesium iron inosilicate such as actinolite; magnesium iron inosilicate such as anthophyllite, etc.), phyllosilicates (for example, aluminum phyllosilicate such as palygorskite), tectosilicates, etc.; silicates such as these; calcium sulfate (for example, dehydrated or anhydrous gypsum); and those derived from sulfates such as mineral wool (for example, rock or slag wool), etc., can generally be used. For use in the present invention, glass fibers such as E-glass, A-glass, C-glass, D-glass, AR-glass, R-glass, S1-glass, S2-glass, etc., and those formed from mixtures thereof are particularly suitable. If desired, the glass fibers can be supplied together with a sizing agent or other coating agents known in the art.

[0041]

[0042] The inorganic fibers can have any desired cross-sectional shape, such as circular or flat. In certain embodiments, it may be desirable to use fibers having a relatively flat cross-sectional dimension by having an aspect ratio (i.e., the width of the cross-section divided by the thickness of the cross-section) of about 1.5 to about 10, in some embodiments about 2 to about 8, and in some embodiments about 3 to about 5. When such flat fibers are used at a specific concentration, the mechanical properties of the molded part can be further improved without substantially adversely affecting the melt viscosity of the polymer composition. The inorganic fibers can have a nominal width, for example, of about 1 to about 50 micrometers, in some embodiments about 5 to about 50 micrometers, and in some embodiments about 10 to about 35 micrometers. The fibers can also have a nominal thickness of about 0.5 to about 30 micrometers, in some embodiments about 1 to about 20 micrometers, and in some embodiments about 3 to about 15 micrometers. Further, the inorganic fibers can have a narrow size distribution. That is, at least about 60 volume %, in some embodiments at least about 70 volume %, and in some embodiments at least about 80 volume % of the fibers can have a width and / or thickness within the above ranges. In the molded part, the volume average length of the glass fibers can be about 10 to about 500 micrometers, in some embodiments about 100 to about 400 micrometers, and in some embodiments about 150 to about 350 micrometers.

[0042]

[0043] Organosilane compounds can also be used in certain embodiments. Such organosilane compounds typically account for about 0.01 wt% to about 3 wt% of the polymer composition, in some embodiments about 0.02 wt% to about 1 wt%, and in some embodiments about 0.05 to about 0.5 wt%. The organosilane compounds can be, for example, any alkoxysilane known in the art, such as vinyl alkoxysilane, epoxy alkoxysilane, amino alkoxysilane, mercapto alkoxysilane, and combinations thereof. In one embodiment, for example, the organosilane compound has the following general formula: R 5 -Si-(R 6 ) 3 [wherein, R 5 is a sulfide group (e.g., -SH), an alkyl sulfide containing 1 to 10 carbon atoms (e.g., mercaptopropyl, mercaptoethyl, mercaptobutyl, etc.), an alkenyl sulfide containing 2 to 10 carbon atoms, an alkynyl sulfide containing 2 to 10 carbon atoms, an amino group (e.g., NH 2 ), an aminoalkyl containing 1 to 10 carbon atoms (e.g., aminomethyl, aminoethyl, aminopropyl, aminobutyl, etc.); an aminoalkenyl containing 2 to 10 carbon atoms, and an aminoalkynyl containing 2 to 10 carbon atoms, etc.; R 6 is an alkoxy group having 1 to 10 carbon atoms, such as methoxy, ethoxy, and propoxy) may have.

[0043]

[0044] Some representative examples of organosilane compounds that can be contained in the mixture include mercaptopropyltrimethoxysilane, mercaptopropyltriethoxysilane, aminopropyltriethoxysilane, aminoethyltriethoxysilane, aminopropyltrimethoxysilane, aminoethyltrimethoxysilane, ethylenetrimethoxysilane, ethylenetriethoxysilane, ethynetrimethoxysilane, ethynetriethoxysilane, aminoethylaminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropylmethyldimethoxysilane or 3-aminopropylmethyldiethoxysilane, N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, N-methyl-3-aminopropyltrimethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, bis(3-aminopropyl)tetramethoxysilane, bis(3-aminopropyl)tetraethoxydisiloxane, γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, γ-aminopropylmethyldimethoxysilane, γ-aminopropylmethyldiethoxysilane, N-(β-aminoethyl)-γ-aminopropyltrimethoxysilane, N-phenyl-γ-aminopropyltrimethoxysilane, γ-diallylaminopropyltrimethoxysilane, γ-diallylaminopropyltrimethoxysilane, etc., and combinations thereof. Particularly preferred organosilane compounds are 3-aminopropyltriethoxysilane and 3-mercaptopropyltrimethoxysilane.

[0044]

[0045] If desired, siloxane polymers can also be used in the polymer composition. Without intending to be limited by theory, it is believed that siloxane polymers can improve the processing of the composition, for example, by providing, among other things, better mold filling, internal lubrication, mold release, etc. Further, it is also considered that siloxane polymers are less likely to move or diffuse to the surface of the composition, which further minimizes the possibility of phase separation and further helps to reduce the impact energy. As an example, such siloxane polymers typically have a weight average molecular weight of about 100,000 grams / mole or more, in some embodiments about 200,000 grams / mole or more, and in some embodiments about 500,000 grams / mole to about 2,000,000 grams / mole. Siloxane polymers can also have a relatively high kinematic viscosity, for example, about 10,000 centistokes or more, in some embodiments about 30,000 centistokes or more, and in some embodiments about 50,000 to about 500,000 centistokes.

[0045]

[0046] Any of a variety of high molecular weight siloxane polymers can generally be used in the polymer composition. In certain embodiments, for example, the siloxane polymer is mainly R 3 SiO 1 / 2 and SiO 4 / 2It may be an "MQ" resin which is a polymer formed from units (each an M and Q unit) (wherein R is a functional or non-functional organic group). Suitable organic functional groups ("R") include, for example, alkyl (such as methyl, ethyl, propyl, butyl, etc.), aryl (such as phenyl), cycloalkyl (such as cyclopentyl), arylenyl, alkenyl, cycloalkenyl (such as cyclohexenyl), alkoxy (such as methoxy), etc., and combinations thereof. Such resins are generally prepared by chemically bonding (copolymerizing) MQ resin molecules of low weight average molecular weight (e.g., less than 100,000 grams / mol) with a polysiloxane linker. In a particular embodiment, by way of example, the resin can be formed by copolymerizing a low molecular weight MQ solid resin (A) with a substantially linear polydiorganosiloxane linker (B) as described, for example, in U.S. Patent No. 6,072,012 (by Juen et al.). Resin (A) has, by way of example, the following general formula: R 1 a R 2 b R 3 c SiO (4-a-b-c) / 2 [wherein, R 1 is a hydroxyl group; R 2 is a monovalent hydrocarbon group having at least one unsaturated carbon-carbon bond capable of undergoing an addition reaction with a silicon-bonded hydrogen atom (i.e., vinyl); each R 3 is independently selected from the group consisting of alkyl, aryl and arylalkyl groups; a is a number from 0 to 1, in some embodiments from 0 to 0.2; b is a number from 0 to 3, in some embodiments from 0 to 1.5; c is a number of 0 or more] and may have M and Q siloxy units.

[0046]

[0047] The substantially linear polydiorganosiloxane linker (B) similarly also has the following general formula: (R 4 (3-p) R 5 p SiO 1 / 2 )(R 4 2 SiO 2 / 2 ) x ((R 4 R 5 SiO 2 / 2 )(R 4 2 SiO 2 / 2 ) x ) y (R 4 (3-p) R 5 p SiO 1 / 2 ) [wherein, each R 4 is independently a monovalent group selected from the group consisting of alkyl, aryl, and arylalkyl groups; each R 5 is independently a monovalent group selected from the group consisting of hydrogen, hydroxyl, alkoxy, oximo, alkyloximo, and aryloximo groups, where at least two R 5 groups are typically present in each molecule and are bonded to different silicon atoms; p is 0, 1, 2, or 3; x ranges from 0 to 200, and in some embodiments ranges from 0 to 100; y ranges from 0 to 200, and in some embodiments ranges from 0 to 100] and may have.

[0047]

[0048] The polymeric siloxane polymer typically accounts for about 0.05 wt% to about 5 wt% of the polymer composition, in some embodiments about 0.1 wt% to about 3 wt%, and in some embodiments about 0.5 to about 2 wt%.

[0048]

[0049] In certain embodiments, the siloxane polymer can be provided in the form of a masterbatch containing a carrier resin. The carrier resin can, for example, account for from about 0.05 wt% to about 5 wt% of the polymer composition, in some embodiments from about 0.1 wt% to about 3 wt%, and in some embodiments from about 0.5 to about 2 wt%. Any of a variety of carrier resins can be used, such as polyolefins (e.g., ethylene polymers, propylene polymers, etc.), polyamides, etc. In one embodiment, for example, the carrier resin is an ethylene polymer. The ethylene polymer can be a copolymer with an α-olefin such as ethylene and C 3 ~C 20 α-olefins or C 3 ~C 12 α-olefins. Suitable α-olefins can be linear or branched (e.g., having one or more C 1 ~C 3 alkyl branches, or aryl groups). Specific examples include 1-butene, 3-methyl-1-butene, 3,3-dimethyl-1-butene, 1-pentene, 1-pentene having one or more methyl, ethyl, or propyl substituents, 1-hexene having one or more methyl, ethyl, or propyl substituents, 1-heptene having one or more methyl, ethyl, or propyl substituents, 1-octene having one or more methyl, ethyl, or propyl substituents, 1-nonene having one or more methyl, ethyl, or propyl substituents, ethyl, methyl or dimethyl-substituted 1-decene, 1-dodecene, and styrene. Particularly desirable α-olefin comonomers are 1-butene, 1-hexene, and 1-octene. The ethylene content of such copolymers can be from 60 mol% to about 99 mol%, in some embodiments from about 80 mol% to about 98.5 mol%, and in some embodiments from about 87 mol% to about 97.5 mol%. The α-olefin content can similarly range from about 1 mol% to about 40 mol%, in some embodiments from about 1.5 mol% to about 15 mol%, and in some embodiments from about 2.5 mol% to about 13 mol%. The density of the ethylene polymer can vary depending on the type of polymer used, but is generally from about 0.85 to about 0.96 grams per cubic centimeter (g / cm 3) ranges. Polyethylene "plastomers" can have a density in the range of, for example, about 0.85 to about 0.91 g / cm 3 Similarly, as measured according to ASTM D792, "linear low density polyethylene" (LLDPE) can have a density in the range of about 0.91 to about 0.940 g / cm 3 "Low density polyethylene" (LDPE) can have a density in the range of about 0.910 to about 0.940 g / cm 3 "High density polyethylene" (HDPE) can have a density in the range of about 0.940 to about 0.960 g / cm 3 Some non-limiting examples of high molecular weight siloxane polymer masterbatches that can be used include, for example, those available under the trade names MB50-001, MB50-002, MB50-313, MB50-314, and MB50-321 from Dow Corning.

[0049]

[0050] If desired, a nucleating agent can also be used to further enhance the crystallization properties of the composition. One example of such a nucleating agent is an inorganic crystalline compound such as a boron-containing compound (e.g., boron nitride, sodium tetraborate, potassium tetraborate, calcium tetraborate, etc.), an alkaline earth metal carbonate (e.g., calcium magnesium carbonate), an oxide (e.g., titanium oxide, aluminum oxide, magnesium oxide, zinc oxide, antimony trioxide, etc.), a silicate (e.g., talc, sodium aluminum silicate, calcium silicate, magnesium silicate, etc.), an alkaline earth metal salt (e.g., calcium carbonate, calcium sulfate, etc.). Boron nitride (BN) has been found to be particularly beneficial when used in the polymer compositions of the present invention. Boron nitride exists in a variety of crystalline forms (e.g., h-BN - hexagonal, c-BN - cubic or sphalerite, and w-BN - wurtzite), and generally any of these can be used in the present invention. The hexagonal form is particularly suitable due to its stability and softness.

[0050]

[0051] Other components that may be included in the composition include, for example, particulate fillers (such as talc, mica, etc.), antibacterial agents, pigments (such as black pigments), antioxidants, stabilizers, surfactants, waxes, flow promoters, solid solvents, flame retardants, and other materials added to enhance properties and processability.

[0051] II. Melt Processing

[0052] The method of combining the polyarylene sulfide and any optional filler can be various as is known in the art. For example, the materials may be fed simultaneously or sequentially to a melt processing apparatus that dispersively blends the materials. Batch and / or continuous melt processing techniques can be used. For example, a mixer / kneader, Banbury mixer, Farrell continuous mixer, single-screw extruder, twin-screw extruder, roll mill, etc. can be utilized to blend and melt process the materials. A particularly preferred melt processing apparatus is a co-rotating twin-screw extruder (for example, a co-rotating fully intermeshing twin-screw extruder manufactured by Leistritz). Such an extruder may include a feed section and a discharge section and provides high-intensity distribution and dispersion mixers. For example, the components can be fed to the same or different feed sections of the twin-screw extruder and melt blended to form a substantially uniformly melted mixture. The melt blending can occur under high shear / high pressure and can be heated to ensure sufficient dispersion. For example, the melt processing can occur at a temperature of about 100 °C to about 500 °C, and in some embodiments, about 150 °C to about 300 °C. To react the polyarylene sulfide with the impact modifier in the presence of a crosslinking system, various different techniques can be used in the present invention. Similarly, the apparent shear rate during melt processing is about 100 seconds -1 ~ about 10,000 seconds -1 and in some embodiments, about 500 seconds -1 ~ about 1,500 seconds -1 and may be in the range. Of course, other variables such as the residence time during melt processing, which is inversely proportional to the throughput rate, can also be controlled to achieve the desired degree of uniformity.

[0052]

[0053] One or more dispensing and / or dispersive mixing elements may be used inside the mixing section of the melt processing unit, according to requirements. Suitable dispensing mixers include, for example, Saxon, Dulmage, Cavity Transfer mixers, etc. Similarly, suitable dispersive mixers include Blister rings, Leroy / Maddock, CRD mixers, etc. As is well known in the art, the mixer may be further strengthened by using pins in the barrel that create folding and reorientation of the polymer melt, such as those used in Buss Kneader extruders, Cavity Transfer mixers, and Vortex Intermeshing Pin mixers. Also, the screw speed can be controlled to improve the properties of the composition. For example, the screw speed may be about 400 rpm or less, and in one embodiment, for example, about 200 rpm to about 350 rpm, or about 225 rpm to about 325 rpm. In one embodiment, the balance of compounding conditions can be adjusted to provide a polymer composition with improved properties. For example, the compounding conditions may include a screw design that provides weak, medium, or strong screw conditions. For example, the system may have a weak screw design where the screw has a single melting section in the downstream half of the screw for gentle melting and distributive melt homogenization. A medium-strength screw design can have a more powerful melting section upstream of the filler feed barrel focused by a more powerful dispersive element for uniform melting. Additionally, it may have another gentle mixing section downstream for mixing the filler. This mixing section can be weaker than the weak strength design but, in addition to the shear strength of the screw, can be made more powerful overall. A highly strong screw design can have the strongest shear strength among the three. The main melting section can be composed of a long array of highly dispersive kneading blocks. The downstream mixing section can achieve uniform dispersion of all types of fillers by utilizing a mix of dispensing and intensive dispersive elements. The shear strength of a highly strong screw design may be significantly higher than that of the other two designs.In one embodiment, the system can include a medium to strong screw design with a relatively moderate screw speed (e.g., from about 200 rpm to about 300 rpm).

[0053]

[0054] The crystallization temperature of the resulting polymer composition (before being molded into a molded part) can be about 250 °C or lower, in some embodiments from about 100 °C to about 245 °C, and in some embodiments from about 150 °C to about 240 °C. Also, the melting temperature of the polymer composition can be in the range of about 250 °C to about 320 °C, and in some embodiments from about 260 °C to about 300 °C. The melting temperature and crystallization temperature can be determined as is well known in the art using differential scanning calorimetry in accordance with ISO test number 11357-3:2018.

[0054] III. Spacer Frame

[0055] The polymer composition can be molded into the form of a spacer frame using any of a variety of techniques as are known in the art. In certain embodiments, by way of example, the molded part can be molded by molding techniques such as injection molding, compression molding, nano molding, overmolding, blow molding, thermoforming, etc., melt extrusion techniques such as the tubular trapped bubble film method, flat or tube cast film method, slit die flat cast film method, or otherwise.

[0055]

[0056] Figure 1 illustrates one embodiment of a bipolar electrode alkaline electrolyzer cell 10 that can include spacer frames 2, 12 for an alkaline electrolyzer, one or both of which can be molded from a polymer composition. In the illustrated embodiment, the first spacer frame 2 for an alkaline electrolyzer can hold the bipolar electrode 4. As illustrated, the spacer frame 2 for an alkaline electrolyzer can define a flow channel 6 that extends between an inlet 5 through which fluid can enter the cathode side of the cell 10 and be directed to the cathode side of the bipolar electrode 4 and the flow channel 8, and an outlet 7 through which fluid can exit from the cathode side of the cell 10. Inlets 9 and outlets 11 can be associated with similar channels (not shown in FIG. 1) that can direct fluid toward and away from the anode side of the bipolar electrode 4 (opposite the illustrated cathode side).

[0056]

[0057] The spacer frame 2 (and any other optional spacers described herein) can also define a seal channel 3 in a surface that can hold a seal to prevent leakage of fluid from the assembled cell 10. It should be understood that the spacer frames 2, 12 are illustrated as generally square plates, but can be of any suitable peripheral shape, such as circular, oval, rectangular, etc. Similarly, the components for the electrolyzer cell held by the spacer frame can have any desired peripheral shape, such as circular as illustrated, as well as any other desired shape.

[0057]

[0058] The bipolar electrode alkaline electrolytic cell 10 can create a physical barrier between the anode and the cathode, and yet surround and hold at least one separator 14 that enables the passage of ions (e.g., hydroxide anions) created on one side of the bipolar electrode 4 to the associated side of an adjacent bipolar electrode (not shown in FIG. 1). A second spacer frame 12 can also be included. The separator 14 can have various different forms as is known in the art. In one embodiment, for example, a "macroporous" separator, such as a fibrous mesh or web having a pore size on the order of millimeters or centimeters (e.g., about 0.1 to about 50 millimeters), may be used. The separator 14 can also include a "microporous" separator, also known as a diaphragm. The separator generally has a pore size on the order of micrometers, e.g., about 0.1 micrometer to about 100 micrometers, or in some embodiments about 1 micrometer to about 50 micrometers. Typical microporous separators can include, for example, microporous ceramics, microporous polymer membranes (e.g., porous polyvinyl chloride (PVC), polyolefins, and PTFE). The separator 14 can also include an anion exchange membrane for preventing convection and diffusion while permitting the movement of anions across the membrane. An example of such a membrane is a polyelectrolyte membrane that enables the passage of anions (e.g., hydroxide anions) created on one side of the bipolar electrode 4 to the associated side of an adjacent bipolar electrode (not shown in FIG. 1). The anion exchange membrane can include, for example, a composite of zirconia and polysulfone available under the trade name Zirfon®. Combinations of macroporous separators, microporous separators, and / or anion exchange members can also be used for the separator 14.

[0058]

[0059] The second spacer frame 12 can define an inlet 15 that aligns with the inlet 5 during assembly of the cell 10 to form a cathode supply port 30 for conveying the cathode supply fluid through the assembled cell 10. During assembly of the cell 10, the outlet 17 aligns with the outlet 7, and a cathode outlet 31 for conveying the cathode product fluid through the assembled cell 10 is formed. During assembly of the cell 10, the inlet 19 aligns with the inlet 9, and an anode inlet 32 for conveying the anode supply fluid through the cell 10 is formed. During assembly of the cell 10, the outlet 21 aligns with the outlet 11, and an anode outlet 33 for conveying the anode product fluid through the cell 10 is formed.

[0059]

[0060] Not all of the spacer frames of the cell need to define flow channels therein. As an example, the alkaline electrolytic cell 10 of FIG. 1 includes a spacer frame 12 for the separator 14 that does not define flow channels therein. However, in other embodiments, adjacent spacer frames can define flow channels therein that can align with each other during assembly. FIG. 2 illustrates a bipolar electrode alkaline electrolytic cell 20 that includes a spacer frame 2 for the bipolar electrode 4 as in the cell 10 of FIG. 1. The spacer frame 22 of the electrolytic cell 20 holds the separator 14 and the inlets and outlets 15, 17, 19, 21. The spacer frame 22 also defines flow channels 16, 18 within the surface of the spacer frame 22. During assembly of the cell 20, the flow channels 16, 18 align with the anode fluid inlet and outlet channels of adjacent spacer frames (not shown in FIG. 2) that hold the bipolar electrodes. The spacer frame 22 can also include lower flow channels (not visible in FIG. 2) of the spacer frame 22 that can align with the cathode inlet and outlet channels 6, 8.

[0060]

[0061] Generally, an alkaline electrolyzer system includes one or more stacks, each stack including a plurality of alkaline electrolyzer cells that are in fluid and electrical communication with each other. FIG. 3 illustrates a representative one stack 35 including five alkaline electrolyzer cells 10 that match with each other. The individual alkaline electrolyzer cells 10 can be connected to each other, for example, by adhesion, welding, bolting, or by using a case or shell that holds the individual components of the stack together with a pressure seal. Stack 35 can include additional spacers in addition to the spacer frames 2, 12 (FIG. 1) of each cell 10. By way of example, stack 35 can include one or more end alkaline electrolyzer spacer plates 40. In an embodiment, the spacer plate 40 can be associated with the current collectors 41, 42 at either end of the cell. For example, the current collectors 41, 42 can be adhered to the surface of the spacer plate 40 and placed in electrical communication with the plurality of cells 10 and an external circuit. Of course, stack 35 can include any number of individual electrolyzer cells, for example, in some embodiments, it can include hundreds of cells.

[0061]

[0062] An alkaline electrolytic cell including one or more spacer frames is not limited to a bipolar electrode electrolytic cell, and the electrolytic cell can generally include monopolar electrodes and other cell components as known in the art, one or more of which can include a spacer frame of a polymer composition. As an example, FIG. 4 illustrates a unipolar electrode alkaline electrolytic cell 70 including a cathode 50 and an anode 60 separated by a separator 74. As shown, the cathode 50 can be held by a spacer frame 52 surrounding the cathode 50. The spacer frame 52 can define the respective cathode and anode supply inlets 55, 59 and the respective cathode and anode product outlets 57, 51 as described above. The surface of the spacer frame 52 can also define flow channels 56, 58 for delivering the cathode flow to and from the cathode 50. The anode 60 can be held by a spacer frame 62 and can define the respective cathode and anode supply inlets 65, 69 and the respective cathode and anode product outlets 67, 61. The unseen back surface of the spacer frame 62 can also define flow channels for delivering the anode flow to and from the anode 60. The spacer frame 72 can hold the separator 74 therein and can define flow channels 76, 78 that can match the unseen flow channels on the back side of the spacer frame 62 to facilitate flow to and from the anode 60. Similarly, the flow channels 56, 58 of the spacer frame 52 can match the flow channels on the back side of the spacer frame 72 to facilitate flow to and from the cathode 50. The alkaline electrolytic cell 70 also includes spacer frames 82 at either end of the cell 70, each holding a bipolar plate 80. The bipolar plate 80 can provide electrical conductivity between adjacent cells of the cell stack and can generally be a plate of any surrounding shape (e.g., circular as shown) formed from a metal such as titanium or stainless steel.

[0062]

[0063] Additional spacer frames or spacer plates for alkaline electrolytic cells, which are known in the art and contain the described polymer compositions, can be introduced into the cell. For example, in some embodiments, the electrolytic cell can include a gas diffusion layer, which is generally located between the bipolar plate and the electrode. The gas diffusion layer can be held by the spacer frame for alkaline electrolytic cells described herein. Of course, the alkaline electrolytic cell can also include spacer frames and spacer plates made from materials other than the polymer compositions of the present invention, if desired.

[0063] IV. Electrolytic Cell System

[0064] The spacer frame for alkaline electrolytic cells may be used in an anion exchange alkaline electrolytic cell system. Referring to FIG. 5, for example, an embodiment of an alkaline electrolytic cell system containing an alkaline electrolytic cell stack 35 incorporating a plurality of the bipolar electrode electrolytic cells 10 is illustrated. Of course, any alkaline electrolytic cell or stack thereof containing a spacer frame and thus a polymer composition may be incorporated into the alkaline electrolytic cell system. In the illustrated embodiment, feed materials can be supplied to both sides of the electrolytic cell stack 35 via a cathode inlet 30 to the cathode side of the cell and an anode inlet 32 to the anode side of the cell. In some embodiments, the feed materials can be supplied to only one side of the cells of the stack 35. In such embodiments where the cell includes an anion exchange membrane separator, the feed materials can be supplied to both sides of the cell to maintain hydration of the membrane. Product outlets 31, 33 can deliver electrolytic products (e.g., oxygen and hydrogen) from the cell stack 35. The feed materials can be an aqueous alkaline solution, for example, without limitation, an aqueous solution of a suitable alkali such as potassium hydroxide, sodium hydroxide, lithium hydroxide, or mixtures thereof. By way of example, the feed materials can contain from about 20 wt% to about 40 wt% alkali (in the aqueous solution).

[0064]

[0065] The feedstock can be supplied to inlets 30, 32 via a common supply line 121 and a recycle hose 122. In embodiments, the feedstock going to the cell can be pre-treated by initially supplying it to a heat exchanger 108 and heating the feedstock 120 to a suitable temperature (e.g., about 80° C.). The outlets 31, 33 can convey the oxygen and hydrogen products to additional system components such as product separators 112, 114, a demister 128, and a dryer 129. The separated hydrogen and oxygen products of the cell stack 35 can be delivered from systems 125, 130. As an example, the hydrogen product can be delivered directly to the system for utilization purposes, e.g., to a fuel cell as fuel, to a storage facility, or to a secondary system for further processing, e.g., for chemical formation.

[0065]

[0066] To operate the alkaline electrolyzer cell stack 35, an aqueous pump 134 is operated to introduce the feedstock 120 into any pre-treatment procedure, e.g., heating via a heat exchanger 108, and then introducing it via inlets 32, 33 to one or both sides of the electrochemical cell stack. In some embodiments, the feedstock can be supplied to both sides of the cell stack 35 to provide a high enough moisture content to cell components (e.g., an anion exchange membrane) to enable the performance of the cell stack 35.

[0066]

[0067] At the cathode of the anion exchange electrolyzer (or the cathode side of the bipolar electrode), water undergoes the half-reaction: 2H 2 O + 2e - → H 2 + 2OH - according to:

[0067]

[0068] The hydroxide ions thus formed at the cathode are conveyed to the anode where the half-reaction: 2OH - → 1 / 2O 2 + H 2 O + 2e - occurs according to:

[0068]

[0069] Subsequently, oxygen and hydrogen are discharged from the cell stack 35 via outlets 31, 33. Generally, the products can be discharged together with the feedstock as long as the feedstock is supplied in a sufficient amount to purge the products from the cell stack 35. Thereafter, the oxygen and hydrogen products can be separated from the residual feedstock, for example, via product separators 112, 114, demister 128, and dryer 129, and purified hydrogen product 130 and oxygen product 125 are obtained. The separated feedstock can be recycled to the cell stack 35 via recycle hose 122.

[0069]

[0070] One or more parameters described herein can be determined using the following test methods.

Example

[0070] Test Method

[0071] Melt Viscosity: The melt viscosity (Pa·s) can be determined using a Dynisco LCR7001 capillary rheometer according to ISO11443:2021 at a shear rate of 400 s -1 The rheometer orifice (die) can have a diameter of 1 mm, a length of 20 mm, an L / D ratio of 20.1, and an entrance angle of 180°. The barrel diameter can be 9.55 mm + 0.005 mm, and the rod length was 233.4 mm. The melt viscosity is typically determined at a temperature of 310 °C.

[0071]

[0072] Melting Temperature: The melting temperature (“Tm”) can be determined by differential scanning calorimetry (“DSC”) known in the art. For semi-crystalline and crystalline materials, the melting temperature is the differential scanning calorimetry (DSC) peak melting temperature determined according to ISO11357:2018. Under the DSC procedure, the sample was heated and cooled at 10 °C / min using a DSC measurement method performed on a TA Q2000 instrument.

[0072]

[0073] Tensile modulus of elasticity, tensile breaking stress, and tensile breaking strain: Tensile properties can be tested in accordance with ISO 527-2 / 1A:2019 (technically equivalent to ASTM D638-14). Coefficient and strength measurements may be performed on the same specimen samples with a length of 80 mm, a thickness of 10 mm, and a width of 4 mm. The test temperature may be 23 °C, and the test speed may be 5 mm / min for tensile strength and tensile breaking strain and 1 mm / min for tensile modulus of elasticity.

[0073]

[0074] Flexural modulus of elasticity and flexural stress: Flexural properties can be tested in accordance with ISO test number 178:2019 (technically equivalent to ASTM D790-17). This test may be carried out with a support span of 64 mm. The test can be performed at the center of an uncut ISO 3167 multi-pass bar. The test temperature may be 23 °C, and the test speed may be 1 or 5 mm / min.

[0074]

[0075] Charpy impact strength: Charpy properties can be tested in accordance with ISO test number ISO 1791:2010 (technically equivalent to ASTM D256-10, method B). This test can be performed using type 1 specimen dimensions (length 80 mm, width 10 mm, and thickness 4 mm). When testing the notched impact strength, the notch may be a type A notch (bottom radius 0.25 mm). The specimen may be cut from the center of a multi-pass bar using a single-flute end mill. The test temperature may be 23 °C or -30 °C.

[0075]

[0076] Chlorine content: Chlorine content can be determined in accordance with elemental analysis using Parr Bomb combustion and subsequent ion chromatography.

[0077] These and other modifications and variations of the present invention can be practiced by those skilled in the art without departing from the spirit and scope of the present invention. Additionally, it should be understood that aspects of the various embodiments can be interchanged, in whole or in part. Further, those skilled in the art will understand that the foregoing description is by way of example only and is not intended to limit the present invention as further described within the scope of the appended claims.

Claims

1. An alkaline electrolyzer system comprising an electrochemical cell proximate to a spacer frame, wherein the spacer frame contains a polymer composition comprising a polymer matrix containing from about 40 wt% to about 95 wt% of at least one polyarylene sulfide and from about 5 wt% to about 60 wt% of at least one filler disposed within the polymer matrix.

2. The alkaline electrolyzer system of claim 1, wherein the filler comprises an impact modifier.

3. The alkaline electrolyzer system of claim 2, wherein the impact modifier comprises an epoxy-functionalized olefin copolymer.

4. The alkaline electrolyzer system of claim 3, wherein the epoxy-functionalized olefin copolymer contains ethylene monomer units.

5. The alkaline electrolyzer system of claim 3, wherein the epoxy-functionalized olefin copolymer contains an epoxy-functional (meth)acrylic monomer component.

6. The alkaline electrolyzer system of claim 2, wherein the polymer composition contains a crosslinked product formed by blending the impact modifier with a crosslinking system.

7. The alkaline electrolyzer system of claim 6, wherein the crosslinking system comprises a metal carboxylate.

8. The alkaline electrolyzer system of claim 6, wherein the crosslinking system comprises an aromatic dicarboxylic acid.

9. The alkaline electrolyzer system of claim 1, wherein the spacer frame includes a curvilinear wall defining a channel, and the curvilinear wall contains the polymer composition.

10. The alkaline electrolyzer system of claim 9, wherein the channel is a seal channel.

11. The alkaline electrolyzer system of claim 9, wherein the channel is a flow channel.

12. The alkaline electrolyzer system of claim 11, wherein the flow channel extends from an inlet or outlet defined in the spacer frame to a component of the electrochemical cell, and the spacer frame surrounds the component.

13. The alkaline electrolyzer system of claim 9, wherein the curvilinear wall has a height of about 1,000 micrometers or less.

14. The alkaline electrolytic cell system according to claim 9, wherein the curved wall defines a circular or helical radius of curvature.

15. An alkaline electrolytic cell system comprising an electrochemical cell proximate to a spacer frame including a curved wall defining a channel, wherein the curved wall contains a polymer composition including a polymer matrix containing at least one polyarylene sulfide.

16. The alkaline electrolytic cell system according to claim 15, wherein the spacer frame includes a curved wall defining a channel, and the curved wall contains the polymer composition.

17. The alkaline electrolytic cell system according to claim 16, wherein the channel is a seal channel.

18. The alkaline electrolytic cell system according to claim 16, wherein the channel is a flow channel.

19. The alkaline electrolytic cell system according to claim 18, wherein the flow channel extends from an inlet or outlet defined in the spacer frame to a component of the electrochemical cell, and the spacer frame surrounds the component.

20. The alkaline electrolytic cell system according to claim 15, wherein the curved wall has a height of about 1,000 micrometers or less.

21. The alkaline electrolytic cell system according to claim 15, wherein the curved wall defines a circular or helical radius of curvature.

22. The polymer composition has a melt viscosity of about 2,000 Pa·s or less as measured according to ISO 11443:2021 at a temperature of about 310°C and a shear rate of 1,200 s －１ The alkaline electrolytic cell system according to claim 1.

23. The alkaline electrolytic cell system according to claim 1, wherein the polymer composition has a chlorine content of about 1,200 ppm or less.

24. The polymer composition exhibits a notched Charpy impact strength of about 20 kJ / m as measured at a temperature of 23 °C in accordance with ISO test number 179-1:2010 ２ The alkaline electrolytic cell system according to claim 1, which exhibits a notched Charpy impact strength of 2 or more.

25. The polymer composition exhibits a notched Charpy impact strength of about 10 kJ / m measured at a temperature of -30°C in accordance with ISO test number 179-1:2010 ２ The alkaline electrolytic cell system according to claim 1, which exhibits a notched Charpy impact strength of 0.000003 or more

26. The alkaline electrolytic cell system according to claim 1, wherein the polymer composition exhibits a tensile strength of about 20 MPa or more, a tensile fracture strain of about 20% or more, and / or a tensile modulus of about 10,000 MPa or less as measured at a temperature of 23 °C according to ISO 527:2019.

27. The alkaline electrolytic cell system according to claim 1, wherein the polymer composition exhibits a flexural strength of about 20 MPa or more and / or a flexural modulus of about 10,000 MPa or less as measured at a temperature of 23 °C according to ISO 178:2019.

28. The alkaline electrolytic cell system according to claim 1, wherein the polyarylene sulfide includes polyphenylene sulfide.

29. The alkaline electrolytic cell system according to claim 1, wherein the electrochemical cell contains a separator located between electrodes.

30. The alkaline electrolytic cell system according to claim 1, wherein the spacer frame surrounds the components of the electrochemical cell.

31. The alkaline electrolytic cell system according to claim 30, wherein the components of the electrochemical cell include electrodes.

32. The alkaline electrolytic cell system according to claim 30, wherein the components of the electrochemical cell include a separator.

33. The alkaline electrolytic cell system according to claim 30, wherein the separator includes an anion exchange member.

34. The alkaline electrolytic cell system according to claim 30, wherein the components of the electrochemical cell include a bipolar plate.

35. The alkaline electrolytic cell system according to claim 1, wherein the spacer frame is adjacent to the end of a cell stack containing the electrochemical cell.

36. The alkaline electrolytic cell system according to claim 35, wherein the spacer frame is located adjacent to a current collector.

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