Protein-based coupling agents for carbon fibers

Abstract

A composition comprising carbon fibers and hydrolyzed protein, wherein, when calculated relative to the total amount of hydrolyzed protein and carbon fibers, the carbon fibers are present in an amount of 85.0000 to 99.9995% by weight, and the hydrolyzed protein is present in an amount of 0.0005 to 15.0000% by weight, and the composition further comprises a curable resin or prepolymer component having at least one ethylenically unsaturated polymerizable group and water in an amount ranging from 0.0 to 10.0% by weight when calculated relative to the total weight of the composition.

Description

Technical Field

[0001] The present invention relates to a composition containing carbon fiber and hydrolyzed protein, wherein the carbon fiber is present in an amount of 85.0000 to 99.9995% by weight and the hydrolyzed protein is present in an amount of 0.0005 to 15.0000% by weight when calculated based on the total amount of the hydrolyzed protein and the carbon fiber. The present invention further relates to a method for producing a carbon fiber composite material and to the carbon fiber composite material. The present invention further relates to an additive composition and to the use of the additive composition.

Background Art

[0002] Carbon fiber reinforced composite materials contain carbon fibers embedded in a polymer matrix. The polymer matrix functions as a binder between the fibers. The matrix polymer may be a thermoplastic polymer and / or a crosslinked polymer. Carbon fibers generally improve the mechanical properties of the composite material compared to the individual matrix polymer. While achieving an improvement in tensile strength and stiffness, the composite material is of low density. Such materials have favorable properties for use in vehicles for air transportation and land transportation because their light weight results in, for example, less fuel and energy consumption for engine-driven vehicles. Carbon fiber composite materials are used in other fields where it is desired to have both high mechanical strength and light weight, such as in wind energy like the rotor blades of wind turbines, aircraft, automobiles, sports goods like tennis rackets and hockey sticks, and safety protection clothing like safety boots.

[0003] Additives that function as coupling agents between carbon fibers and polymer matrices have already been described. Such coupling agents can improve the bonding strength between carbon fibers and polymer matrices and thus improve the overall mechanical properties of carbon fiber composite materials.

[0004] International Publication No. 2014 / 071517 relates to biocomposite materials. These composite materials are produced by embedding fibrous material in a polymer matrix containing animal protein and a crosslinking agent, and then curing it. Several problems occurred during mechanical testing. For example, the dataset showed a fairly large standard deviation, many specimens broke outside the center, the sample surface was not uniform, the actual sample thickness varied, delamination of the fibrous layer occurred, there were problems with the distribution of fibers, and the specimens were wet or over-humidified (page 14,

[0065] -

[0066] ). These results are consistent with the findings of the present invention that using large amounts of protein does not lead to an improvement in the overall mechanical properties of the fibrous composite material, but rather is detrimental. [Overview of the project] [Problems that the invention aims to solve]

[0005] An additive is needed that functions as a coupling agent for carbon fibers used in composite materials, thereby suppressing the aforementioned drawbacks. Furthermore, it is desirable that the additive effectively improves the mechanical properties of carbon fiber composite materials even when applied in small amounts. Another object of the present invention is to provide an environmentally friendly and easily biodegradable coupling agent. Furthermore, it is desirable that the coupling agent be cost-effective and easily obtainable. [Means for solving the problem]

[0006] In view of the above, the present invention provides a composition comprising carbon fibers, hydrolyzed protein, a curable resin or prepolymer component having at least one ethylenically unsaturated polymerizable group, and optionally, an amount of water in the range of 0.0 to 10.0% by weight when calculated relative to the total weight of the composition, wherein, when calculated relative to the total amount of hydrolyzed protein and carbon fibers, the carbon fibers are present in an amount of 85.0000 to 99.9995% by weight, and the hydrolyzed protein is present in an amount of 0.0005 to 15.0000% by weight.

[0007] Hydrolysis is a chemical reaction in which one water molecule breaks one or more chemical bonds. There are various types of hydrolysis, including chemical hydrolysis, physical hydrolysis, and enzymatic hydrolysis. "Hydrolysis" refers to the cleavage of amide bonds in a polypeptide to produce shorter amino acid chains having carboxylic acid functional groups and amino groups. Protein hydrolysis generally produces proteins and peptides of various molecular weights, as well as free amino acids. As used herein, the term "hydrolyzed protein" refers to a mixture of proteins, peptides, and / or free amino acids produced by protein hydrolysis.

[0008] Typically, different types of hydrolysis are used in combination to obtain hydrolyzed proteins. For example, the protein is first extracted by hot water treatment and then further hydrolyzed enzymatically. Parameters such as pH, temperature, and pressure can be adjusted to obtain the desired results.

[0009] Enzymatic catalysis enables the enzymatic hydrolysis of proteins. Hydrolases are a type of enzyme that generally functions as a biochemical catalyst, using water to break chemical bonds, which usually splits larger molecules into smaller ones. Some common examples of hydrolase enzymes include esterases, such as lipases, phosphatases, glycosidases, peptidases, and nucleosidases. Examples of peptidases include pepsin and trypsin.

[0010] In one embodiment, the hydrolysis step includes alkaline hydrolysis, in which the protein is hydrolyzed in the presence of a base. In one embodiment, the base includes an aqueous solution of an alkali metal hydroxide or an alkaline earth metal hydroxide. In one embodiment, the alkaline hydrolysis can be carried out at high temperature and pressure for a time long enough to produce hydrolyzed protein of the desired size. For example, the alkaline hydrolysis can be carried out at a temperature of about 150°C and a pressure of about 400 kPa.

[0011] In another embodiment, the hydrolysis step includes thermal hydrolysis. For example, the protein may be exposed to a temperature of at least about 180°C and a pressure of about 1,200 kPa for a period of time sufficient to produce a hydrolyzed protein of the desired size.

[0012] The conditions and type of hydrolysis can be selected by those skilled in the art to produce hydrolyzed proteins with a desired degree of hydrolysis. Severe hydrolysis conditions produce relatively smaller peptides and more individual amino acids. Milder hydrolysis conditions produce relatively larger peptides.

[0013] Preferably, the hydrolyzed protein includes or contains hydrolyzed proteins of animal or plant origin, or mixtures thereof. Preferably, the hydrolyzed protein is derived from animals such as pigs, chickens, and cattle. Furthermore, the hydrolyzed protein may be bovine protein, bovine serum-derived protein, pigskin-derived protein, and / or casein, or other milk-derived protein. Preferred plant-derived proteins are, for example, those derived from peas, soybeans, wheat, and potatoes.

[0014] More preferably, the hydrolyzed protein is derived from collagen. Collagen is a major structural protein of the extracellular matrix found in various connective tissues of the body. As a major component of connective tissue, collagen is the most abundant protein in mammals. Collagen consists of amino acids that combine to form collagen helices. Collagen is mainly found in connective tissues such as cartilage, bone, tendons, ligaments, and skin.

[0015] Commercially available gelatin used in food and industry is partially hydrolyzed collagen, typically having a molecular weight of 100-500 kDa. Gelatin can form gels, having a gel strength of approximately 30-300 gram bloom when using the Bloom test for gel strength. This gelling gelatin is also called type G gelatin. Gelatin itself should not be understood as a hydrolyzed protein according to the present invention and does not exhibit the desired effect, as shown by experiments performed. Suitable is hydrolyzed gelatin, preferably having a gel strength of less than 30 gram bloom, more preferably less than 20 gram bloom, and even more preferably less than 10 gram bloom. Most preferably, the hydrolyzed gelatin has a gel strength of 0-20 gram bloom, or even 0 gram bloom. Non-gelling types of gelatin, also known as type F gelatin or collagen peptides, are mainly composed of low molecular weight components. Preferably, the hydrolyzed protein is non-gelling and therefore unable to form a gel.

[0016] Gelatin gel strength (jelly strength, bloom) is the mass in grams required to press a standard plunger (AOAC plunger, 12.70 mm (0.500 inch) diameter, flat surface and sharp edge, no measurable radius) 4 mm into a gel with a concentration of 6.67% that has been aged at 10.0°C for 17 hours. Suitable instruments for testing gel strength are gelometers, such as the Lloyd TA Plus, LFRA Texture Analyser (Brookfield), LFRA Texture Analyse CT3 (Brookfield), Texture Analyser TA-XTplus (Stable Micro Systems), Texture Analyser TA-XT2i (Stable Micro Systems), and Zwick / Roell.

[0017] To evaluate gel strength, a 6.67% solution of the gelatin sample was prepared in a wide-mouth test bottle (capacity approximately 155 ml, inner diameter 59 mm + / 1 mm, total height 85 mm, flat bottom) using 7.50 g of gelatin and 105 mL of deionized water at 60°C. The solution was then cooled to 10.0°C and aged at this temperature for 17 hours.

[0018] Preferably, the hydrolyzed protein has a molecular weight distribution in which at least 50% by weight of the hydrolyzed protein is in the range of 1,000 g / mol to 100,000 g / mol. More preferably, the hydrolyzed protein has a molecular weight distribution in which at least 50% by weight of the hydrolyzed protein is in the range of 1,000 to 75,000 g / mol. Even more preferably, the hydrolyzed protein has a molecular weight distribution in which at least 50% by weight of the hydrolyzed protein is in the range of 1,000 to 50,000 g / mol, and most preferably, the hydrolyzed protein has a molecular weight distribution in which at least 50% by weight of the hydrolyzed protein is in the range of 5,000 to 50,000 g / mol.

[0019] The molecular weight is determined by high-performance size exclusion chromatography (HPSEC).

[0020] Column: Support: Silica; Particle size: 5 micrometers; Pore size: 125 angstroms; Inner diameter: 7.8 mm × Length: 30 cm; (TSK G 2000 SWXL 5μm (Ref. 0008540 Tosoh Bioscience GmbH)) Guard column: Carrier: Silica; Particle size: 7 micrometers; Inner diameter 6 mm × length 4 cm (TSK SWXL Guardcol 7 μm (Ref. 0008543, Tosoh Bioscience GmbH)).

[0021] A 1 L aqueous solution is prepared by dissolving 13.27 g of KH2PO4, 0.445 g of Na2HPO4, and 11.69 g of NaCl as the eluent.

[0022] Calibration standard substance: Narrow-range calibration: FILK calibration solution (CNBr bovine); Wide-range calibration: Standard substance for wide-range calibration with commercially available GME porcine collagen peptide (Gelita Eberbach).

[0023] In one embodiment, the hydrolyzed protein is part of an additive composition comprising the hydrolyzed protein and at least one polar solvent, where the polar solvent comprises at least one polymer based on ethylene oxide or propylene oxide and mixtures thereof, and optionally, the end groups are etherified with an alkyl group having 1 to 6 carbon atoms. Preferably, the end groups are etherified with an alkyl group having 1 to 4 carbon atoms. A polymer is defined as a molecule having at least two repeating units.

[0024] Preferably, the additive composition, when calculated based on the total weight of the hydrolyzed protein and the polar solvent, 0.1 to 99.0 wt% of the hydrolyzed protein, 1.0 to 99.9 wt% of the polar solvent and.

[0025] More preferably, the additive composition, when calculated based on the total weight of the hydrolyzed protein and the polar solvent, 0.1 to 75.0 wt% of the hydrolyzed protein, 25.0 to 99.9 wt% of the polar solvent and.

[0026] Even more preferably, the additive composition, when calculated based on the total weight of the hydrolyzed protein and the polar solvent, 0.1 to 50.0 wt% of the hydrolyzed protein, 50.0 to 99.9 wt% of the polar solvent and.

[0027] Most preferably, the additive composition, when calculated based on the total weight of the hydrolyzed protein and the polar solvent, 0.1 to 35.0 wt% of the hydrolyzed protein, 65.0-99.9% by weight of a polar solvent and Includes.

[0028] At least one polar solvent comprises at least one polymer based on ethylene oxide or propylene oxide and mixtures thereof, wherein the terminal groups are optionally etherified with alkyl groups having 1 to 6 carbon atoms, and preferably has a molecular weight of 100 to 1000 g / mol. More preferably, the polar solvent has a molecular weight of 100 to 800 g / mol, even more preferably 200 to 800 g / mol, and most preferably 200 to 700 g / mol. The molecular weight of the polar solvent can be appropriately determined by measuring the hydroxyl group content of the hydroxyl terminal segment, for example by titration (ISO 4629-1:2016).

[0029] Suitablely, the polar solvent comprises at least one of methoxypolyethylene glycol, polyethylene glycol, and polypropylene glycol.

[0030] In the compositions according to the present invention, any known type of carbon fiber can be used, excluding carbon nanofibers and other nanomaterials. Preferably, the carbon fiber has a diameter of at least 1 micrometer based on the minimum dimension in one dimension. More preferably, the carbon fiber has a diameter of at least 2 micrometers, and even more preferably, at least 3 micrometers. Most preferably, the carbon fiber has a diameter in the range of 3 to 10 micrometers or 3 to 20 micrometers. Examples of carbon fibers include amorphous carbon fibers and graphite fibers. Carbon fibers produced from various starting materials are equally suitable, for example, carbon fibers prepared from polyacrylonitrile, pitch, rayon, or bio-based raw materials. The carbon fibers may be subjected to chemical or mechanical surface pretreatment using known sizing agents during fiber production, for example. Carbon fibers that have not been subjected to specific pretreatment can also be used. It is preferable that the carbon fibers have already been subjected to sizing treatment.

[0031] Depending on the application, carbon fibers can exist as filament fibers, staple fibers, or chopped fibers. In some embodiments, carbon fibers exist as woven or nonwoven fabrics. In other embodiments, carbon fibers exist as rovings.

[0032] The composition according to the present invention is very suitable for the preparation of carbon fiber composite materials. Therefore, the composition may contain further components and materials commonly used in the manufacture of carbon fiber composite materials.

[0033] The composition further comprises a curable resin or prepolymer component having at least one ethylenically unsaturated polymerizable group. The curable resin or prepolymer component generally forms a matrix polymer of the carbon fiber composite material. Such curable resins are well known in the art. Due to the presence of the resin in the composition, the composition generally becomes paste-like or liquid at a temperature of 23°C. Examples include unsaturated polyester resins, such as polyester resins having unsaturated groups based on maleic acid or fumaric acid. In other embodiments, the curable resin may be a polyurethane resin having ethylenically unsaturated polymerizable groups, for example, a polyurethane resin having one or more acrylate or methacrylate end groups, or a polyurethane produced by reacting an isocyanate and a polyol, often in the presence of a catalyst or by exposure to ultraviolet light. Other examples of suitable resins include epoxy acrylates, also known as vinyl ester resins, which are resins produced by esterifying epoxy resins with acrylic acid or methacrylic acid, as well as dicyclopentadiene resins, epoxy resins, and so-called (meth)acrylic syrups. Epoxy resins are a type of reactive prepolymer and polymer containing epoxy groups. Epoxy resins are produced, for example, by combining epichlorohydrin and bisphenol A to produce bisphenol A diglycidyl ether. Curable resins or curable prepolymers preferably contain at least one of epoxy resins, epoxy acrylates (vinyl ester resins), or polyurethane resins.

[0034] The composition may also contain further components commonly used in the manufacture of carbon fiber composite materials. Examples of such components include thermoplastic resins or polymers, organic or inorganic fillers and pigments, thickeners, UV stabilizers, mold release agents, defoamers, and monomers or SS linkers having ethylenically unsaturated polymerizable groups, such as acrylates and methacrylates, or vinyl aromatic compounds. Curing initiators, such as organic peroxides, azo initiators, or benzopinacol, or curing agents, such as amines, anhydrides, and isocyanates, may also be included in the composition.

[0035] The composition is calculated based on the total amount of hydrolyzed protein, carbon fiber, and curable resin or prepolymer. 30.0000 to 89.9995% by weight of carbon fiber, 0.0005 to 5.0000% by weight of hydrolyzed protein, 10.0000 to 69.9995% by weight of a curable resin or curable prepolymer and It is preferable to include it.

[0036] The composition is calculated based on the total amount of hydrolyzed protein, carbon fiber, and curable resin or prepolymer. 40.0000 to 89.9995% by weight of carbon fiber, 0.0005 to 5.0000% by weight of hydrolyzed protein, 10.0000 to 59.9995% by weight of a curable resin or curable prepolymer and It is more preferable to include it.

[0037] The composition is calculated based on the total amount of hydrolyzed protein, carbon fiber, and curable resin or prepolymer. 40.00-89.99% by weight of carbon fiber, 0.01-3.00% by weight of hydrolyzed protein, 10.00 to 59.99% by weight of a curable resin or curable prepolymer and It is even more preferable to include

[0038] The composition is calculated based on the total amount of hydrolyzed protein, carbon fiber, and curable resin or prepolymer. 45.00-84.99% by weight of carbon fiber, 0.01-3.00% by weight of hydrolyzed protein, 15.00 to 54.99% by weight of a curable resin or curable prepolymer and It is most preferable to include [this].

[0039] The composition is a non-aqueous composition. A non-aqueous composition is substantially water-free. A non-aqueous composition refers to a paste-like or liquid composition containing an amount of water in the range of 0.0 to 10.0% by weight, preferably 0.0 to 7.0% by weight, relative to the total weight of the composition. More preferably, a non-aqueous composition contains 0 to 5.0% by weight of water. For example, the composition contains less than 3.0% by weight or less than 1.0% by weight of water, relative to the total weight of the composition. Suitablely, the composition contains 0 to 3.0% by weight of water, or 0 to 1.0% by weight of water, relative to the total weight of the composition.

[0040] Ideally, hydrolyzed proteins are present in a polar solvent. Examples of suitable polar solvents include methoxypolyethylene glycol, polyethylene glycol, polypropylene glycol, and mixtures thereof.

[0041] Preferably, the polar solvent comprises at least one polymer and / or mixture thereof based on ethylene oxide or propylene oxide, the terminal groups of which are etherified with alkyl groups having 1 to 6 carbon atoms. More preferably, the polar solvent comprises at least one of methoxypolyethylene glycol, polyethylene glycol, and polypropylene glycol. Most preferably, the polar solvent comprises at least one of methoxypolyethylene glycol 350 (MPEG 350), methoxypolyethylene glycol 500 (MPEG 500), and polypropylene glycol 600 (PPG 600). In a further embodiment, the polar solvent comprises methoxypolyethylene glycol, polyethylene glycol, and / or polypropylene glycol.

[0042] Appropriately, the composition is calculated relative to the total weight of the hydrolyzed protein, carbon fiber, and polar solvent, 0.0005 to 15.0000% by weight of hydrolyzed protein, 60.0000 to 99.9495% by weight of carbon fiber, 0.0500 to 25.0000% by weight of a polar solvent and Includes.

[0043] More precisely, the composition is calculated relative to the total weight of the hydrolyzed protein, carbon fiber, and polar solvent, 0.0005 to 15.0000% by weight of hydrolyzed protein, 60.0000 to 99.9495% by weight of carbon fiber, 0.0500 to 25.0000% by weight of a polar solvent and Includes.

[0044] More precisely, the composition is calculated relative to the total weight of the hydrolyzed protein, carbon fiber, and polar solvent, 0.0005 to 15.0000% by weight of hydrolyzed protein, 70.0000 to 99.9495% by weight of carbon fiber, 0.0500 to 15.0000% by weight of a polar solvent and Includes.

[0045] Most appropriately, the composition is calculated relative to the total weight of the hydrolyzed protein, carbon fiber, and polar solvent, 0.01-10.00% by weight of hydrolyzed protein, 75.00-99.94% by weight of carbon fiber, 0.05 to 15.00 wt% polar solvent and Includes.

[0046] Furthermore, the composition is appropriately calculated relative to the total weight of the hydrolyzed protein, curable resin or curable prepolymer, carbon fiber and polar solvent, 0.0005 to 5.0000% by weight of hydrolyzed protein, A curable resin or curable prepolymer in an amount of 10.0000 to 69.9495% by weight, 0.0500 to 7.0000% by weight of a polar solvent, 30.0000 to 89.9495% by weight of carbon fiber and Includes.

[0047] More specifically, the composition is calculated relative to the total weight of the hydrolyzed protein, curable resin or curable prepolymer, carbon fiber and polar solvent, 0.01-3.00% by weight of hydrolyzed protein, A curable resin or curable prepolymer in an amount of 10.00 to 69.94% by weight, 0.05 to 7.00 wt% polar solvent, 30.00-89.94% by weight of carbon fiber and Includes.

[0048] More specifically, the composition is calculated relative to the total weight of the hydrolyzed protein, curable resin or curable prepolymer, carbon fiber and polar solvent, 0.01-3.00% by weight of hydrolyzed protein, A curable resin or curable prepolymer in an amount of 15.00 to 59.94% by weight, 0.05 to 7.00 wt% polar solvent, 40.00-84.94% by weight of carbon fiber and Includes.

[0049] Most appropriately, the composition is calculated relative to the total weight of the hydrolyzed protein, curable resin or curable prepolymer, carbon fiber and polar solvent, 0.01-3.00% by weight of hydrolyzed protein, A curable resin or curable prepolymer in an amount of 15.00 to 59.94% by weight, 0.05 to 5.00 wt% polar solvent, 40.00-84.00% by weight of carbon fiber and Includes.

[0050] The present invention also relates to a method for producing carbon fiber composite materials. This method is - When calculated based on the total weight of carbon fiber, hydrolyzed protein, and curable resin or curable prepolymer, a) 30.0000 to 89.9995% by weight of carbon fiber, b) 0.0005 to 5.0000% by weight of hydrolyzed protein, c) 10.0000 to 69.9995% by weight of a curable resin or curable prepolymer A step of providing a composition containing, - A step of curing the composition to produce a carbon fiber composite material. Includes.

[0051] Preferably, the method for producing the carbon fiber composite material is: - When calculated based on the total weight of carbon fiber, hydrolyzed protein, and curable resin or curable prepolymer, a) 40.00-84.99% by weight of carbon fiber, b) 0.01-3.00% by weight of hydrolyzed protein, c) 15.00 to 59.99% by weight of a curable resin or curable prepolymer A step of providing a composition containing, - A step of curing the composition to produce a carbon fiber composite material. Includes.

[0052] The curing process can be carried out in any manner known in the art. Curing can be carried out at room temperature, but is preferably carried out at high temperatures. It is possible to start at ambient temperature and then achieve a temperature increase by utilizing the exothermic behavior of the system. It is also possible to forcibly raise the temperature by optionally combining external heating with pressurization.

[0053] Typical procedures include sheet molding compounding (SMC), bulk molding compounding (BMC), infusion molding (RIM: resin impregnation molding, RTM: resin transfer molding), compression molding, VARI (vacuum resin impregnation molding), filament winding, pultrusion, and autoclave curing.

[0054] In general, the same descriptions provided above with respect to the compositions of the present invention also apply to the compositions used in the methods of the present invention.

[0055] When preparing a composition for use in this method, the individual components can be added and mixed in any suitable order. Preferably, the hydrolyzed protein is added to the carbon fiber before the curable resin or curable prepolymer, simultaneously with the curable resin or curable prepolymer, or after the curable resin or curable prepolymer.

[0056] In some embodiments, the additive is added to the carbon fibers before the composition contains the curable resin or prepolymer components. The additive can be added to the carbon fibers immediately after the fiber's manufacture, before or after the fiber's cutting, shredding, or weaving. The additive can be applied to the carbon fibers in any suitable way, for example, by spraying a pure or diluted additive onto the surface of the fibers, or by immersing the fibers in an additive that may optionally be diluted with a solvent. It is also possible to apply the additive to woven, nonwoven, or roving carbon fibers. In another preferred embodiment, the additive of the present invention is applied to the carbon fibers after the initial sizing process is completed.

[0057] Alternatively, the additive may be pre-mixed with the curable resin or prepolymer component and included in the composition together with the curable resin or prepolymer component. In yet another embodiment, the additive is added to the composition after the carbon fibers have been combined with the curable resin or prepolymer component.

[0058] If necessary, the composition can be molded into any suitable shape before curing. Examples of molding operations include introducing the composition into a suitable mold, forming a sheet by winding, rolling, or pressing, and optionally following a cutting process.

[0059] The curing of the composition may occur by radical polymerization. The term radical polymerization may also include processes in which chain transfer reactions occur. In one preferred embodiment, a radical-generating curing agent may be appropriately included in the composition to accelerate the curing reaction. Organic peroxides, azo initiators, and benzopinacol are well-known and suitable radical generators. In addition to or in place of radical generators, irradiation may also be used to achieve the curing process.

[0060] Epoxy resins can self-react through catalytic homopolymerization or react with a wide range of co-reactants, including polyfunctional amines, acids (and acid anhydrides), phenols, alcohols, and thiols (commonly called mercaptans). Common epoxy resins are based on the reaction of epichlorohydrin with bisphenol A to produce a chemical known as bisphenol A diglycidyl ether. Polyurethanes are produced, for example, by reacting isocyanates with polyols in the presence of a catalyst or by exposure to ultraviolet light.

[0061] Curing is preferably carried out at a high temperature, for example, by heating the composition for a sufficient time and temperature to achieve the desired degree of curing. Generally, curing can be carried out in a temperature range of 20 to 240°C, preferably in the range of 40 to 220°C, more preferably in the range of 60 to 210°C, and even more preferably in the range of 80 to 200°C.

[0062] Depending on the process used, curing can be achieved in relatively short periods, such as 20 to 3600 seconds, but can also take up to 4, 6, 12, or even 24 hours. High-temperature curing can be performed in an autoclave or a suitable oven, or directly in a press.

[0063] The present invention further relates to carbon fiber composite materials that can be obtained by any of the methods described.

[0064] The present invention further relates to the use of additive compositions as coupling agents for carbon fiber composites.

[0065] The present invention also relates to the use of additive compositions for improving the mechanical properties of carbon fiber composite materials.

[0066] Experiment Section

[0067] [Table 1-1] [Table 1-2] [Table 1-3]

[0068] General preparation of coupling agents 20 g of protein powder (generally ANiPept M) was weighed into a 250 mL glass flask equipped with a stirrer bar. 80 g of solvent (generally MPEG 350) was added. Each component was mixed with a magnetic stirrer at 200 rpm at room temperature until the protein was dispersed. To avoid precipitation, the sample was stored with stirring until used for further processing.

[0069] General formulation and preparation of epoxy resin systems:

[0070] [Table 2]

[0071] The resin was filled into a 30L hobock, an internal release agent was added, and it was thoroughly mixed by hand. Hardener 1 was added to this mixture and mixed again. The coupling agent was added to this mixture and mixed again by hand. Hardener 2 was weighed separately and added to this mixture, and mixed in a dissolving machine (700 rpm, 4.4 m / s) until completely dissolved.

[0072] The entire mixture was mixed in a dissolving machine at 2000 rpm (12.57 m / s) until it reached a temperature of 30°C.

[0073] Preparation of fabric for epoxy resin: The fabric (generally Zoltek PANEX 35-13 50K) was cut into 950 x 600 mm layers. Two layers were stacked on top of each other, the roving orientation was aligned to 0°, and the layers were weighed after manufacturing to calculate the fiber weight fraction.

[0074] Preparation of chopped fibers for epoxy resin: The SMC line was started with the manufacturing parameters, and dry fibers (generally Panex 35, type 13 sizing) were weighed with lids. The diameter of the lids was 320 mm, which is 1 m 2 This corresponds to a weight of 3000 g / m² per unit area. 2 Therefore, the fiber content inside the lid had to be 125g.

[0075] Manufacturing of epoxy SMC

[0076] [Table 3]

[0077] The resin-based solution was distributed to the two doctor blades.

[0078] When using fabric as a reinforcing material: The packages were inserted into the SMC line, and this procedure was repeated until all the fabric was used up. At the end of the SMC line, each package was separated individually and placed flat on a table. After all packages had passed through, they were bundled together and packaged, and stored in a heated storage room at 30°C for 14 days.

[0079] When using chopped fiber as a reinforcing material: The chopped carbon fibers (in a combination of 25mm and 50mm lengths) were dropped from the cutter onto the resin on the SMC line. This compound was processed through the line, rolled up at the end, and stored in a heated storage chamber at 30°C for 14 days.

[0080] Molding of epoxy SMC after maturation

[0081] [Table 4]

[0082] After maturation, the SMC was cut to a size of 390 x 290 mm. Four layers of fabric-based SMC were formed, and two layers of chopped fiber-based SMC were formed. All layers were weighed, and the fiber weight fraction of the final component was calculated.

[0083] To improve the processing during molding, the prepared SMC was stored overnight at 20°C before molding.

[0084] The mold release agent was applied to the mold with a brush. The mold release agent was also applied to the base plate. The plate was molded for 300 seconds and then heated to the processing temperature.

[0085] Both the SMC and the base panel were placed inside the mold and molded for 200 seconds. After 200 seconds, the base plate was removed and molded for another 90 seconds.

[0086] All panels were weighed, and the fiber weight fraction of the final component was calculated. The panels were then optically inspected.

[0087] [Table 5]

[0088] The vinyl ester resin was weighed into a 30 L hobock and thoroughly mixed with saturated polyester by hand. The processing additive was added to this mixture and mixed by hand. Next, the peroxide was added and mixed by hand. The coupling agent and LDPE were added and mixed separately. Then, this mixture was mixed in a dissolver at 2000 rpm (12.57 m / s) until it reached a temperature of 30°C. Finally, the magnesium oxide paste for thickening was added while mixing at 700 rpm (4.4 m / s) until it was completely dissolved. Then, this mixture was mixed at 700 rpm (4.4 m / s) for 1 minute.

[0089] For spray coating, vinyl ester resin was prepared in the same manner, but without using a coupling agent.

[0090] Preparation of fabrics for vinyl ester: The fabric (ZOLTEK PANEX 35-13 50K) was cut into 950 x 600 mm layers. The two layers were stacked on top of each other, the roving orientation was aligned to 0°, and they were weighed after manufacturing to calculate the fiber weight fraction.

[0091] Preparation and spray coating of fabrics for vinyl ester resins: The fabric (Mitsubishi TR50S 12K) was cut into square sheets with sides measuring 600 mm. The additive was sprayed onto both sides of the square sheets using a SAT Jet 30 HVLP Digital spray gun with a 1.3 mm spray nozzle. The amount of coupling agent applied was 6.5 g per sheet (18.05 g / m²). 2 ) was.

[0092] The carbon fiber composition was stored at 23°C for 24 hours before impregnation with a curable resin.

[0093] Preparation of chopped fibers for vinyl ester resins: The SMC line was started with the manufacturing parameters, and dry fibers (Panex 35, type 13 sizing) were weighed with lids. The diameter of the lids was 320 mm, which is 1 m 2 This corresponds to a weight of 3000 g / m² per unit area. 2 Therefore, the fiber content inside the lid had to be 125g.

[0094] Manufacturing of vinyl ester SMC

[0095] [Table 6]

[0096] The resin-based solution was distributed to the two doctor blades.

[0097] When using fabric as a reinforcing material: The packages were inserted into the SMC line, and this procedure was repeated until all the fabric was used up. At the end of the SMC line, each package was separated individually and placed flat on a table. After all packages had passed through, they were bundled together and packaged, and stored in a heated storage room at 30°C for 1 day.

[0098] When using chopped fiber as a reinforcing material: The chopped carbon fibers (in a combination of 25mm and 50mm lengths) were dropped from the cutter onto the resin on the SMC line. This compound was processed through the line, rolled at the end, and stored in a heated storage room at 30°C for one day.

[0099] Molding of vinyl ester SMC after maturation

[0100] [Table 7]

[0101] After maturation, the SMC was cut to a size of 390 x 290 mm. Four layers of fabric-based SMC were formed, and two layers of chopped fiber-based SMC were formed. All panels were weighed, and the fiber weight fraction of the final component was calculated.

[0102] Molding and spray coating of vinyl ester SMC after maturation. The above stack was molded and cured using a Zeulenroda PYXZ press at 150°C and a pressure of 133 bar for 120 seconds.

[0103] Mechanical testing of reinforced specimens These panels were cut with a saw (Diamant Boart DV 27, diamond blade). For tensile strength measurement in accordance with DIN EN ISO 527-4:1997-07, carbon fiber composite sheets were cut into specimens with sides of 150 mm × 2 to 10 mm. For transverse tensile strength measurement in accordance with DIN EN ISO 527-5B, carbon fiber composite sheets were cut into specimens with sides of 250 mm × 25 mm. For flexural strength measurement in accordance with DIN EN ISO 14125, carbon fiber composite sheets were cut into specimens with sides of 80 mm × 15 mm. Flexural strength measurements were performed parallel to the fiber direction.

[0104] [Table 8]

[0105] Prior to testing, all test specimens were stored for 24 hours at 23°C and 50% relative humidity.

[0106] After the experiment, the results were evaluated and converted to average fiber weight fractions within a single experimental setup.

[0107] Concentration in epoxy resin systems A coupling agent was prepared using 20% ​​ANiPept M and 80% MPEG 350 according to the general preparation of coupling agents. Reinforcement samples were prepared using the resin described in the general formulation and preparation of epoxy resin systems and the fabric described in the preparation of fabrics for epoxy resins. Epoxy SMC was prepared according to the manufacture of epoxy SMC and molded according to the molding of aged epoxy SMC. Mechanical properties were tested according to the mechanical tests of reinforcement samples.

[0108] The improvement in mechanical properties is shown in Table 3 below as the difference (%) compared to a control plate without a coupling agent.

[0109] [Table 9]

[0110] As the concentration of moderately sized hydrolyzable proteins increased, the lateral tensile strength, flexural strength, and elastic flexural strength also increased.

[0111] Physical form of coupling agent A coupling agent was prepared according to the general preparation of coupling agents and added to the resin at a concentration of 5% by weight. Reinforcement samples were prepared using the resin described in the general formulation and preparation of epoxy resin systems and the fabric described in the preparation of fabric for epoxy resin. TRAC 0061 H was used as the curing agent 2. Epoxy SMC was prepared according to the manufacture of epoxy SMC and molded according to the molding of aged epoxy SMC. Mechanical properties were tested according to the mechanical tests of reinforcement samples.

[0112] The improvement in mechanical properties is shown in Table 4 below as the difference (%) compared to a control plate without a coupling agent.

[0113] [Table 10]

[0114] Table 4 shows that, in addition to the addition of hydrolyzed protein in powder form, the addition of hydrolyzed protein dispersion also increases lateral tensile strength and flexural strength.

[0115] Alternative carbon fabric combined with epoxy resin The coupling agent was prepared according to the general preparation of the coupling agent. The protein concentration in the solvent is shown in Table 5 below. The coupling agent was added at 5% by weight relative to the resin. The reinforcement sample was prepared using the epoxy resin described in the general formulation and preparation of epoxy resin systems, according to the preparation of fabric for epoxy resin. TRAC 0061 H was used as the curing agent 2. The differences in the fabrics are shown in the table below.

[0116] The improvement in mechanical properties is shown in Table 5 below as the difference (%) compared to a control plate without a coupling agent.

[0117] [Table 11]

[0118] It was found that the mechanical properties of epoxy carbon composite materials using various carbon fabrics were significantly improved by adding a hydrolyzed protein dispersion.

[0119] Alternative curing systems, internal release agents, and fabrics A coupling agent was prepared using 20% ​​ANiPept M and 80% MPEG 350 according to the general preparation of coupling agents, and was applied to the resin at a concentration of 5% by weight. Reinforcement samples were prepared using the epoxy resin described in the general formulation and preparation of epoxy resin systems, according to the preparation of fabrics for epoxy resins. Differences in curing agents, internal release agents, and fabrics are shown in Table 6 below.

[0120] The improvement in mechanical properties is shown in the table below as the difference (%) compared to a control plate without a coupling agent.

[0121] [Table 12]

[0122] Table 6 shows that even when various curing systems, internal release agents, and carbon fabrics are used, the addition of hydrolyzed protein dispersion significantly improves the mechanical properties.

[0123] Change of reinforcing material A coupling agent was prepared according to the general preparation of coupling agents using 20% ​​ANiPept M and 80% MPEG 350, and applied to the resin at a concentration of 5% by weight. Reinforcement samples were prepared according to the general formulation and preparation of resin systems for epoxy resins, using Panex 35 carbon fiber, type 13 sizing, in accordance with the preparation of chopped fibers for epoxy resins.

[0124] The improvement in mechanical properties is shown in Table 7 below as the difference (%) compared to a control plate without a coupling agent.

[0125] [Table 13]

[0126] Table 7 shows that adding hydrolyzable proteins to the application system significantly improves its mechanical properties.

[0127] Size distribution of protein hydrolysates A coupling agent was prepared using 20% ​​protein hydrolysate (shown in Table 8 below) and 80% MPEG 350 according to the general preparation of coupling agents, and was applied to the resin at a concentration of 5% by weight. Reinforcement samples were prepared using the epoxy resin described in the general formulation and preparation of epoxy resin systems, according to the preparation of fabrics for epoxy resins.

[0128] The improvement in mechanical properties is shown in the table below as the difference (%) compared to a control plate without a coupling agent.

[0129] [Table 14]

[0130] Hydrolyzable proteins with different size distributions (1-100 kDa) all showed an improvement effect on the mechanical properties of epoxy-carbon composite materials.

[0131] Alternative solvents A coupling agent was prepared using 20% ​​ANiPept M and 80% solvent according to the general preparation of coupling agents, and was applied to the resin at a concentration of 5% by weight. The various solvents are shown in Table 9 below. Reinforcement samples were prepared using the epoxy resin described in the general formulation and preparation of epoxy resin systems, according to the preparation of fabrics for epoxy resins.

[0132] The improvement in mechanical properties is shown in Table 9 below as the difference (%) compared to a control plate without a coupling agent.

[0133] [Table 15]

[0134] Table 9 shows that hydrolyzable proteins were found to improve the mechanical properties in various polar solvents.

[0135] Alternative protein sources A coupling agent was prepared using 20% ​​protein and 80% MPEG 350 according to the general preparation of coupling agents, and was added to the resin at a concentration of 5% by weight. The protein sources are shown in Table 10 below. Reinforcement samples were prepared using the epoxy resin described in the general formulation and preparation of epoxy resin systems, according to the preparation of fabrics for epoxy resins.

[0136] The improvement in mechanical properties is shown in Table 10 below as the difference (%) compared to a control plate without a coupling agent.

[0137] [Table 16]

[0138] The mechanical properties of carbon fiber composites are significantly improved by protein hydrolysates derived from various sources (plant-based or animal-based). Non-hydrolyzable proteins, such as gelatin (type G gelatin), could not be incorporated into the system, making it impossible to measure their mechanical properties.

[0139] Vinyl ester resin The coupling agent was prepared using 20% ​​ANiPept M and 80% MPEG 350 according to the general preparation of the coupling agent. Various concentrations for the resin system are shown in Table 11 below. Reinforcement samples were prepared using the vinyl ester resin described in the formulation and preparation of the vinyl ester resin system, and the fibers described in the preparation of chopped fibers for vinyl ester.

[0140] The improvement in mechanical properties is shown in Table 11 below as the difference (%) compared to a control plate without a coupling agent.

[0141] [Table 17]

[0142] Table 11 shows that improvements in mechanical properties were also achieved with vinyl ester carbon composite materials.

[0143] Vinyl ester resin-based, spray coating The coupling agent was prepared using 20% ​​ANiPept M and 80% MPEG 350 according to the general preparation of the coupling agent. The reinforcement sample was prepared using the vinyl ester resin described in the formulation and preparation of vinyl ester resins (for spray coating) and the fibers described in the preparation of vinyl ester fabrics for spray coating.

[0144] The improvement in mechanical properties is shown in Table 12 below as the difference (%) compared to a control plate without a coupling agent.

[0145] [Table 18]

[0146] First, a coupling agent was spray-coated onto the fabric, and then a vinyl ester resin was added, which improved the mechanical properties.

Claims

1. A composition, wherein the composition a) Carbon fiber and, b) A curable resin or prepolymer component having at least one ethylenically unsaturated polymerizable group, c) an amount of water in the range of 0.0 to 10.0% by weight when calculated relative to the total weight of the composition, d) Hydrolyzed proteins and Includes, A composition in which, when calculated relative to the total amount of hydrolyzed protein and carbon fiber, the carbon fiber is present in an amount of 85.0000 to 99.9995% by weight, and the hydrolyzed protein is present in an amount of 0.0005 to 15.0000% by weight.

2. The above composition is calculated based on the total amount of hydrolyzed protein, carbon fiber, and curable resin or prepolymer. 30.0000 to 89.9995% by weight of carbon fiber, 0.0005 to 5.0000% by weight of hydrolyzed protein, 10.0000 to 69.9995% by weight of a curable resin or curable prepolymer The composition according to claim 1, comprising:

3. The composition according to claim 1 or 2, wherein the curable resin or curable prepolymer comprises at least one of epoxy resin, vinyl ester resin, or polyurethane resin.

4. The composition according to any one of claims 1 to 3, wherein the hydrolyzed protein is present in a polar solvent.

5. The composition according to any one of claims 1 to 4, wherein the polar solvent comprises at least one polymer based on ethylene oxide or propylene oxide and mixtures thereof, and optionally the terminal groups are etherified with alkyl groups having 1 to 6 carbon atoms.

6. The composition according to any one of claims 1 to 5, wherein the hydrolyzed protein comprises or contains an animal-derived or plant-derived hydrolyzed protein or a mixture thereof.

7. The composition according to any one of claims 1 to 6, wherein the hydrolyzed protein is derived from collagen.

8. The composition according to any one of claims 1 to 7, wherein the hydrolyzed protein has a molecular weight distribution in which at least 50% of the hydrolyzed protein is in the range of 1,000 g / mol to 100,000 g / mol.

9. When the composition is calculated relative to the total weight of the hydrolyzed protein, the carbon fiber, and the polar solvent, 0.0005 to 15.0000% by weight of the hydrolyzed protein, The carbon fiber in an amount of 60.0000 to 99.9495% by weight, 0.0500 to 25.0000% by weight of the polar solvent and A composition according to any one of claims 1 to 8, comprising:

10. When the composition is calculated relative to the total weight of the hydrolyzed protein, the curable resin or curable prepolymer, the carbon fiber, and the polar solvent, 0.0005 to 5.0000% by weight of the hydrolyzed protein, A curable resin or curable prepolymer in an amount of 10.0000 to 69.9495% by weight, A polar solvent in an amount of 0.0500 to 7.0000% by weight, 30.0000 to 89.9495% by weight of the carbon fiber and A composition according to any one of claims 1 to 9, comprising:

11. A method for manufacturing carbon fiber composite materials, i) When calculated based on the total weight of carbon fiber, hydrolyzed protein, and curable resin or curable prepolymer, a) 30.0000 to 89.9995% by weight of carbon fiber, b) 0.0005 to 5.0000% by weight of hydrolyzed protein, c) 10.0000 to 69.9995% by weight of a curable resin or curable prepolymer A step of providing a composition containing, ii) A step of curing the composition to produce a carbon fiber composite material. Methods that include...

12. The method according to claim 11, wherein the hydrolyzed protein is added to the carbon fiber before the curable resin or curable prepolymer, simultaneously with the curable resin or curable prepolymer, or after the curable resin or curable prepolymer.

13. A carbon fiber composite material that can be obtained by the method described in claim 11 or 12.

14. An additive composition, wherein the additive composition, Hydrolyzed protein and at least one polar solvent and An additive composition comprising, wherein the polar solvent comprises at least one polymer based on ethylene oxide or propylene oxide and mixtures thereof, and optionally the terminal groups are etherified with alkyl groups having 1 to 6 carbon atoms.

15. When the composition is calculated relative to the total weight of the hydrolyzed protein and the polar solvent, 0.1 to 50.0% by weight of the hydrolyzed protein, 50.0 to 99.9% by weight of the polar solvent and The additive composition according to claim 14, comprising:

16. The additive composition according to claim 14 or 15, wherein the polar solvent has a molecular weight of 100 to 1000 g / mol.

17. The additive composition according to any one of claims 14 to 16, wherein the polar solvent comprises at least one of methoxypolyethylene glycol, polyethylene glycol, and polypropylene glycol.

18. Use of the additive composition according to any one of claims 14 to 17 as a coupling agent for carbon fiber composite materials.

19. Use of the additive composition according to any one of claims 14 to 18 for improving the mechanical properties of a carbon fiber composite material.

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