Sizing agent for reinforcing fiber, reinforcing fiber, and composite material

Abstract

The sizing agent for reinforcing fibers according to the present invention is characterized by containing one or more hydrocarbons (A) selected from the group consisting of mineral oils, liquid paraffins, and polyalphaolefins that are liquid at room temperature, and a nonionic surfactant (B), and by containing more than 0 mass% and less than 50 mass% of the hydrocarbons (A) in the non-volatile components.

Description

Technical Field

[0001] This invention relates to a sizing agent for reinforcing fibers, reinforcing fibers, and composite materials. Background Technology

[0002] Sizing agents are agents applied to fibrous materials such as carbon fibers for purposes such as inhibiting damage to the fiber materials and improving their bundle properties. For example, Japanese Patent Application Publication No. 2006-22441 (Patent Document 1) discloses a carbon fiber sizing agent containing more than 50% by mass of mineral oil, and a thermoplastic resin-reinforced carbon fiber obtained by attaching the sizing agent to carbon fibers. According to the invention described in Patent Document 1, thermoplastic resin-reinforced carbon fibers with excellent adhesion to thermoplastic resins such as polypropylene, as well as excellent fiber opening and scratch resistance, can be provided at low cost.

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent Application Publication No. 2006-22441 Summary of the Invention

[0006] The technical problem that the invention aims to solve

[0007] However, the invention described in Patent Document 1 has room for improvement in terms of the bundle properties of the fiber material after the sizing agent is applied. Furthermore, the fiber material with the sizing agent of Patent Document 1 tends to fuzz when processed after storage.

[0008] Therefore, there is a need for a sizing agent for reinforcing fibers that can improve the bundle properties of fiber materials while suppressing fuzzing during processing after storage, as well as reinforcing fibers and composite materials using the sizing agent for reinforcing fibers.

[0009] Technical solutions to solve technical problems

[0010] The sizing agent for reinforcing fibers of the present invention is characterized in that it contains one or more hydrocarbons (A) selected from mineral oil, liquid paraffin and polyalphaolefins that are liquid at room temperature, and a nonionic surfactant (B), and the proportion of the above hydrocarbons (A) in the non-volatile components is more than 0% by mass and less than 50% by mass.

[0011] The reinforcing fiber of the present invention is characterized in that it is coated with the above-mentioned sizing agent for reinforcing fibers.

[0012] The composite material of the present invention is characterized in that it contains the above-mentioned reinforcing fibers and a matrix resin as a thermosetting resin.

[0013] Compared to the use of conventional sizing agents, these formulations improve the cohesiveness of the fiber material while suppressing fuzzing during processing after storage.

[0014] Preferred embodiments of the present invention will now be described. However, the scope of the present invention is not limited to the preferred embodiments described below.

[0015] In one embodiment, the sizing agent for reinforcing fibers of the present invention preferably contains a polyalphaolefin as the aforementioned hydrocarbon (A), wherein the polyalphaolefin is a 3- to 8-mer of 1-decene.

[0016] This configuration makes it particularly easy to improve the bundle properties of fiber materials.

[0017] In one embodiment, the sizing agent for reinforcing fibers of the present invention preferably contains mineral oil as the aforementioned hydrocarbon (A), wherein the content of the aromatic component of the mineral oil is more than 0% by mass and less than 5% by mass.

[0018] This configuration is particularly effective at suppressing fuzzing of fibrous materials during processing after storage.

[0019] In one embodiment, the sizing agent for reinforcing fibers of the present invention preferably contains mineral oil and polyalphaolefin as the aforementioned hydrocarbon (A).

[0020] This configuration makes it easy to balance the bundled nature of the fiber material with the ability to suppress fuzzing during storage and post-processing.

[0021] In one embodiment, the sizing agent for reinforcing fibers of the present invention preferably contains an alkylene oxide adduct of an aromatic alcohol (B1) as the aforementioned nonionic surfactant (B).

[0022] This configuration facilitates improved adhesion of the sized fiber material to the matrix resin.

[0023] In one embodiment, the sizing agent for reinforcing fibers of the present invention preferably further contains one or more resins (C) selected from thermosetting resins (C1) and polyester resins (C2).

[0024] This configuration facilitates improved adhesion of the sized fiber material to the matrix resin.

[0025] In one embodiment, the sizing agent for reinforcing fibers of the present invention preferably contains a thermosetting resin (C1) as the resin (C).

[0026] This configuration facilitates improved adhesion of the sized fiber material to the matrix resin.

[0027] In one embodiment, the sizing agent for reinforcing fibers of the present invention preferably contains a thermosetting resin (C1) and a polyester resin (C2) as the resin (C).

[0028] This configuration is particularly effective in improving the adhesion of sized fiber materials to the matrix resin.

[0029] In one embodiment, the sizing agent for reinforcing fibers of the present invention preferably comprises, relative to the total mass of the hydrocarbon (A), the nonionic surfactant (B), and the resin (C), the hydrocarbon (A) comprising 0.1% by mass or more and less than 50% by mass, the nonionic surfactant (B) comprising 0.1% by mass or more and less than 50% by mass, and the resin (C) comprising 20% ​​by mass or more and less than 90% by mass.

[0030] This configuration facilitates the high-level bundling of fibrous materials and suppresses fuzzing during processing after storage.

[0031] In one embodiment, the reinforcing fiber of the present invention is preferably an inorganic fiber coated with the above-mentioned sizing agent for reinforcing fibers.

[0032] This configuration makes the present invention readily applicable to the reinforcement of composite materials using resins, ceramics, metals, etc., as base materials.

[0033] In one embodiment, the inorganic fiber in the reinforcing fiber of the present invention is preferably carbon fiber or glass fiber.

[0034] This configuration makes the present invention particularly easy to apply to the reinforcement of composite materials using resins, ceramics, metals, etc. as base materials.

[0035] Further features and advantages of the invention will be made clearer through the following exemplary and non-limiting description of embodiments. Detailed Implementation

[0036] Embodiments of the sizing agent for reinforcing fibers and the reinforcing fibers of the present invention will be described. Hereinafter, examples of applying the sizing agent for reinforcing fibers of the present invention (hereinafter referred to as "sizing agent") to the sizing treatment of fiber materials will be described.

[0037] [Composition of sizing agent]

[0038] The sizing agent of this embodiment contains hydrocarbons (A) and nonionic surfactants (B) as nonvolatile components. Additionally, resin (C) can be optionally included as a nonvolatile component in the sizing agent.

[0039] (hydrocarbons)

[0040] The sizing agent of this embodiment contains one or more hydrocarbons (A) selected from mineral oil, liquid paraffin, and polyalphaolefin. The hydrocarbon (A) is preferably a liquid.

[0041] The proportion of hydrocarbons (A) in the non-volatile components of the sizing agent is greater than 0% by mass and less than 50% by mass. It should be noted that the non-volatile components of the sizing agent refer to the components that remain after the sizing agent has been heated at 105°C in a hot air dryer for 2 hours without volatilizing.

[0042] When the sizing agent contains mineral oil as a hydrocarbon (A), there are no particular restrictions on the mineral oil; either alkane or cycloalkane base oils can be used. The composition of the mineral oil can be represented by cycloalkanes analysis (ndM method). For ease of suppressing fuzzing during processing after storage of the sized fiber material, it is preferable to use a mineral oil with an aromatic hydrocarbon content exceeding 0% by mass and less than 5% by mass in the cycloalkanes analysis. The cycloalkanes content in the cycloalkanes analysis can be, for example, 25% by mass or more and less than 50% by mass, but is not limited thereto. The alkanes content in the cycloalkanes analysis can be, for example, 40% by mass or more and less than 75% by mass, but is not limited thereto.

[0043] The kinematic viscosity of mineral oil at 30°C can be, for example, 10 mm. 2 / s or more, 180mm 2 / s and below, but not limited to this.

[0044] When the sizing agent contains liquid paraffin as a hydrocarbon (A), there are no particular restrictions on the liquid paraffin. The kinematic viscosity of the liquid paraffin at 30°C can, for example, be 5 mm. 2 / s or higher, 120mm 2 / s and below, but not limited to this.

[0045] When the sizing agent contains a polyalphaolefin that is liquid at room temperature as hydrocarbon (A), there are no particular limitations on the polyalphaolefin, as long as it is liquid at room temperature. Non-limiting examples of polyalphaolefins include polymers of 1-hexene, 1-octene, 1-decene, 1-dodecene, or 1-tetradecene (i.e., alpha-olefins with 6 to 14 carbon atoms). The degree of polymerization of the polymer can be, for example, 3 to 8. Particularly preferred is that the sizing agent contains a polyalphaolefin as hydrocarbon (A), which is a 3 to 8-mer of 1-decene.

[0046] The sizing agent preferably contains both mineral oil and polyalphaolefin as hydrocarbons (A). In this case, the conditions for mineral oil and polyalphaolefin are as described above.

[0047] (Nonionic surfactant)

[0048] The sizing agent of this embodiment contains a nonionic surfactant (B). The nonionic surfactant (B) can be any nonionic surfactant commonly used in the art. The nonionic surfactant (B) can be a single compound or a mixture of multiple compounds.

[0049] The nonionic surfactant (B) can be, for example, an alkylene oxide adduct of a compound having a hydroxyl group. Examples of compounds having a hydroxyl group include aromatic alcohols such as tristyrene-modified phenol, stilbene-modified phenol, and bisphenol A, as well as aliphatic alcohols such as dodecyl alcohol, isodecanol, tetradecyl alcohol, tridecanol, tert-dodecyl alcohol, tert-tridecyl alcohol, 2-ethylhexanol, oleyl alcohol, and isononol, with aromatic alcohols being preferred. Examples of alkylene oxides include, but are not limited to, ethylene oxide and propylene oxide. Therefore, the nonionic surfactant (B) is preferably an alkylene oxide adduct of an aromatic alcohol (B1).

[0050] It should be noted that multiple epoxides can be used in combination with nonionic surfactant (B). The number of epoxides added per mole of nonionic surfactant (B) can be more than 6 to less than 40 moles, but is not limited to this.

[0051] Nonionic surfactants (B) can be a single compound or a mixture of multiple compounds.

[0052] (resin)

[0053] The sizing agent of this embodiment may also contain resin (C). Resin (C) is one or more resins selected from thermosetting resin (C1) and polyester resin (C2). For ease of imparting bundled properties to the fiber material, it is preferable that resin (C) contains thermosetting resin (C1). Furthermore, for ease of imparting bundled properties to the fiber material and suppressing pilling during processing after storage of the sizing treatment, it is preferable that resin (C) contains both thermosetting resin (C1) and polyester resin (C2).

[0054] Examples of thermosetting resins (C1) include epoxy resins and vinyl ester resins. Examples of epoxy resins include, but are not limited to, the jER (registered trademark) series (jER 828, jER 834, jER 1001, jER 1002, jER 1004, etc.) manufactured by Mitsubishi Chemical Corporation, the NPES series (NPES301, NPES302, etc.) manufactured by Nan Ya Plastics Industry Co., Ltd., and the SUMI-EPOXY (registered trademark) series (SUMI-EPOXY ELM-434, SUMI-EPOXY ELM-100, etc.) manufactured by Sumitomo Chemical Co., Ltd. Vinyl ester resins can be a reaction product of any of the epoxy resins mentioned above and methacrylic acid. It should be noted that the ratio of reaction substrates used to generate this reaction product can be either equal in epoxy value to acid value in methacrylic acid, or either one can be larger. Furthermore, the thermosetting resin (Cl) can be a single compound or a mixture of multiple compounds.

[0055] Polyester resin (C2) is a copolymer of diol monomers and dicarboxylic acid monomers. Therefore, the molecule of polyester resin (C2) contains diol residues as partial structures from the diol monomer (diol compound or its derivative) and dicarboxylic acid residues as partial structures from the dicarboxylic acid monomer (dicarboxylic acid or its derivative). The composition of polyester resin (C2) is determined by the molar ratio of the monomers constituting the molecule.

[0056] The diol monomer constituting the polyester resin (C2) may include one or more diol compounds. Examples of diol compounds include ethylene glycol, diethylene glycol, bisphenol A, ethylene oxide adducts of bisphenol A (NEWPOL BPE series manufactured by Sanyo Chemical Industries, Ltd., such as NEWPOL BPE-20, NEWPOL BPE-40, and NEWPOL BPE-100), propylene oxide adducts of bisphenol A (NEWPOL BP series manufactured by Sanyo Chemical Industries, Ltd., such as NEWPOL BP-2P, NEWPOL BP-3P, and NEWPOL BP-5P), etc., but are not limited to these.

[0057] The dicarboxylic acid monomer constituting the polyester resin (C2) may include one or more dicarboxylic acid compounds. Examples of dicarboxylic acid compounds include isophthalic acid, terephthalic acid, fumaric acid, maleic acid, and alkali metal salts of 5-sulfoisophthalic acid (e.g., sodium salt, potassium salt, lithium salt, etc.), but are not limited to these.

[0058] As non-limiting examples of polyester resin (C2), examples include copolymers of diethylene glycol, isophthalic acid, and sodium 5-sulfoisophthalate; copolymers of ethylene glycol, diethylene glycol, isophthalic acid, terephthalic acid, and sodium 5-sulfoisophthalate; copolymers of ethylene oxide adduct of bisphenol A and fumaric acid (in other words, copolymers of bisphenol A, ethylene glycol, and fumaric acid); and copolymers of ethylene oxide adduct of bisphenol A and maleic acid (in other words, copolymers of bisphenol A, ethylene glycol, and maleic acid). It should be noted that polyester resin (C2) can be a single compound or a mixture of multiple compounds.

[0059] When the sizing agent contains resin (C), preferably, relative to the total mass of hydrocarbon (A), nonionic surfactant (B), and resin (C), the mass percentage of hydrocarbon (A) is 0.1% by mass or more and less than 50% by mass, the mass percentage of nonionic surfactant (B) is 0.1% by mass or more and less than 50% by mass, and the mass percentage of resin (C) is 20% by mass or more and less than 90% by mass. If the proportions of each component meet the above conditions, it is easy to achieve a high level of balance between fiber material cohesion and suppression of fuzzing during processing after storage.

[0060] (Other ingredients)

[0061] The sizing agent of this embodiment may also contain other components besides hydrocarbons (A), nonionic surfactants (B), and resins (C). Examples of these other components include, but are not limited to, preservatives, antistatic agents, antioxidants, ultraviolet absorbers, defoamers (modified silicones, etc.), and resins other than resin (C).

[0062] Another typical method for using sizing agents in the sizing treatment of fiber materials is to dilute non-volatile components such as hydrocarbons (A) with a diluent (often also called sizing solution). This diluent is an example of other components. Examples of diluents include water (tap water, industrial water, ion-exchanged water, distilled water, etc.), acetone, methyl ethyl ketone, and N-methyl-2-pyrrolidone, but are not limited to these. It should be noted that there is no particular limitation on the concentration of non-volatile components in sizing agents that are diluted with a diluent; for example, it can be 10% by mass or more and 60% by mass or less. As mentioned above, the non-volatile components of a sizing agent refer to the components that remain after heating the sizing agent at 105°C in a hot air dryer for 2 hours without volatilizing, and its concentration refers to the ratio of the mass of the non-volatile components in the sizing agent to the mass of the sizing agent itself.

[0063] [Manufacturing method of sizing agent]

[0064] The sizing agent of this embodiment can be obtained by mixing a hydrocarbon (A), a nonionic surfactant (B), and optional components using a known method. For example, it can be prepared by adding water to the hydrocarbon (A), nonionic surfactant (B), and optional components while stirring for 5 hours at a temperature of 20°C to 90°C.

[0065] [How to use sizing agent]

[0066] The sizing agent of this embodiment is used for sizing treatment of fiber materials. Sizing treatment is the process of attaching a sizing agent to a fiber material. As a method, methods commonly used in the art for attaching such a sizing agent to fiber materials can be applied. That is, methods such as impregnation oiling, spray oiling, roller oiling, and guided oiling can be used. It should be noted that when applying each method, the sizing agent can be appropriately diluted with a diluent such as water.

[0067] There is no particular limitation on the amount of sizing agent adhering to the fiber material. For example, the amount of sizing agent adhering to the fiber material is preferably 0.1% to 3% by mass or more relative to the total amount of fiber material to which the sizing agent is applied.

[0068] It should be noted that when manufacturing the reinforcing fiber, if the sizing agent of this embodiment is used, reinforcing fibers with the sizing agent attached to the fiber material can be obtained. This reinforcing fiber is an example of the reinforcing fiber of the present invention. The fiber material is preferably an inorganic fiber, in which case the reinforcing fiber is an inorganic fiber with the sizing agent attached. Furthermore, carbon fiber or glass fiber is more preferably used as the inorganic fiber.

[0069] These reinforcing fibers can be used in composite materials using resins, ceramics, metals, etc., as the matrix material. One embodiment of the present invention is a composite material characterized by containing the aforementioned reinforcing fibers and a matrix resin as a thermosetting resin.

[0070] [Other Implementation Methods]

[0071] In one embodiment, the present invention can be a sizing agent, characterized in that it contains one or more hydrocarbons (A) selected from mineral oil, liquid paraffin and polyalphaolefin and a nonionic surfactant (B), wherein the hydrocarbon (A) is present in a proportion of more than 0% by mass and less than 50% by mass in the nonvolatile components.

[0072] It should be understood that the embodiments disclosed in this specification are merely illustrative in all respects regarding other configurations, and the scope of the invention is not limited thereto. Those skilled in the art will understand that appropriate modifications can be made without departing from the spirit of the invention. Therefore, other modified embodiments without departing from the spirit of the invention are also included within the scope of the invention.

[0073] Example

[0074] The present invention will be further described below through the illustrated embodiments. However, the present invention is not limited to the following embodiments.

[0075] [Preparation of sizing agent]

[0076] The sizing agents of Examples 1 to 25 shown in Tables 1 and 2 below and Comparative Examples 1 to 3 shown in Table 3 were obtained by the following methods.

[0077] (1) Raw materials

[0078] (1-1) Hydrocarbons

[0079] The following hydrocarbons are used. These hydrocarbons all conform to hydrocarbon (A) of the above-described embodiments. It should be noted that in Tables 1 to 3, the percentage (in mass%) of hydrocarbon (A) in the non-volatile components of the sizing agent is shown in "R". A "column.

[0080] (Hydrocarbon A-1)

[0081] A mineral oil containing 1% by mass of aromatic hydrocarbons, 29% by mass of cycloalkanes, and 70% by mass of alkanes, with a kinematic viscosity of 18 mm at 30°C. 2 / s.

[0082] (Hydrocarbon A-2)

[0083] A mineral oil containing 3% by mass aromatic hydrocarbons, 40% by mass cycloalkanes, and 57% by mass alkanes, with a kinematic viscosity of 52 mmHg at 30°C. 2 / s.

[0084] (Hydrocarbon A-3)

[0085] A mineral oil containing 0.1% by mass of aromatic hydrocarbons, 33% by mass of cycloalkanes, and 66.9% by mass of alkanes, with a kinematic viscosity of 50 mmHg at 30°C. 2 / s.

[0086] (Hydrocarbon A-4)

[0087] A mineral oil containing 1% by mass of aromatic hydrocarbons, 34% by mass of cycloalkanes, and 65% by mass of alkanes, with a kinematic viscosity of 100 mmHg at 30°C. 2 / s.

[0088] (Hydrocarbon A-5)

[0089] A mineral oil containing 4.5% by mass of aromatic hydrocarbons, 43% by mass of cycloalkanes, and 52.5% by mass of alkanes, with a kinematic viscosity of 162 mmHg at 30°C. 2 / s.

[0090] (Hydrocarbon A-6)

[0091] A mineral oil containing 2.5% by mass of aromatic hydrocarbons, 30% by mass of cycloalkanes, and 67.5% by mass of alkanes, with a kinematic viscosity of 14 mm at 30°C. 2 / s.

[0092] (Hydrocarbon A-7)

[0093] A mineral oil containing 11% by mass of aromatic hydrocarbons, 46% by mass of cycloalkanes and 43% by mass of alkanes, with a kinematic viscosity of 28 mm at 30°C. 2 / s.

[0094] (Cyclone A-8)

[0095] The kinematic viscosity at 30℃ is 6 mm. 2 / s of liquid paraffin.

[0096] (Hydrocarbon A-9)

[0097] The kinematic viscosity at 30℃ is 18 mm. 2 / s of liquid paraffin.

[0098] (Hydrocarbon A-10)

[0099] The kinematic viscosity at 30℃ is 35 mm. 2 / s of liquid paraffin.

[0100] (Hydrocarbon A-11)

[0101] The kinematic viscosity at 30℃ is 60 mm. 2 / s of liquid paraffin.

[0102] (Hydrocarbon A-12)

[0103] The kinematic viscosity at 30℃ is 104 mm. 2 / s of liquid paraffin.

[0104] (Hydrocarbon A-13)

[0105] A polyalphaolefin has a kinematic viscosity of 36 mm at 30°C. 2 / s, mainly composed of 1-decene trimer.

[0106] (Hydrocarbon A-14)

[0107] A polyalphaolefin has a kinematic viscosity of 72 mmHg at 30°C. 2 / s, mainly composed of 3- to 5-mers of 1-decene.

[0108] (Hydrocarbon A-15)

[0109] A liquid paraffin, specifically Shell (registered trademark) GTL Solvent GS-310 (manufactured by SHELLLubricants Japan Co., Ltd.), has a kinematic viscosity of 8.3 mm at 30°C. 2 / s.

[0110] (Hydrocarbon A-16)

[0111] A liquid paraffin, commercially available ISANE (registered trademark) BIOLIFE 1518 (manufactured by TotalEnergiesLubricants Japan Co., Ltd.), has a kinematic viscosity of 3.8 mm at 30°C. 2 / s.

[0112] (Hydrocarbon A-17)

[0113] A liquid paraffin, commercially available ISANE (registered trademark) BIOLIFE 58 (manufactured by TotalEnergiesLubricants Japan Co., Ltd.), has a kinematic viscosity of 3.9 mm at 30°C. 2 / s.

[0114] (Hydrocarbon A-18)

[0115] A liquid paraffin, commercially available ISANE (registered trademark) BIOLIFE 78 (manufactured by TotalEnergiesLubricants Japan Co., Ltd.), has a kinematic viscosity of 5.2 mm at 30°C. 2 / s.

[0116] It should be noted that polyalphaolefins (PAOs) are mixtures of oligomers with different degrees of polymerization. The oligomer with the highest molar proportion is considered the main component of the PAO. For example, hydrocarbon A-13 is the PAO with the highest proportion of 1-decene trimer. Furthermore, hydrocarbon A-14 has a higher proportion of 1-decene trimer, tetramer, and pentamer than PAOs with other degrees of polymerization. The proportion of oligomers at each degree of polymerization in a PAO can be determined, for example, by GC-MS (gas chromatography-mass spectrometry).

[0117] (1-2) Nonionic surfactants

[0118] The following nonionic surfactants are used. These nonionic surfactants all conform to the nonionic surfactants (B) of the above embodiments, wherein nonionic surfactants B1-1 to B1-8 conform to the epoxide adducts of aromatic alcohols (B1) of the above embodiments. However, the manufacturing methods shown for each nonionic surfactant are merely examples, and the results of the examples and comparative examples will not change even if the nonionic surfactant is manufactured using a method different from the example method described below.

[0119] (Nonionic surfactant B1-1)

[0120] Tristyrene-modified phenol, ethylene oxide, and propylene oxide were reacted in a molar ratio of 1:15:9 to obtain nonionic surfactant B1-1, which is a random adduct of tristyrene-modified phenol in ethylene oxide and propylene oxide.

[0121] (Nonionic surfactant B1-2)

[0122] Stilbene-modified phenol, ethylene oxide, and propylene oxide were reacted in a molar ratio of 1:20:5 to obtain nonionic surfactant B1-2, which is a random adduct of stilbene-modified phenol in ethylene oxide and propylene oxide.

[0123] (Nonionic surfactant B1-3)

[0124] Bisphenol A and ethylene oxide were reacted at a molar ratio of 1:18 to obtain nonionic surfactant B1-3, which is an ethylene oxide adduct of bisphenol A.

[0125] (Nonionic surfactant B1-4)

[0126] Bisphenol A and ethylene oxide were reacted in a molar ratio of 1:10 to obtain nonionic surfactant B1-4, which is an ethylene oxide adduct of bisphenol A.

[0127] (Nonionic surfactant B1-5)

[0128] Tristyrene-modified phenol and ethylene oxide were reacted in a molar ratio of 1:34 to obtain nonionic surfactant B1-5, which is the ethylene oxide adduct of tristyrene-modified phenol.

[0129] (Nonionic surfactant B1-6)

[0130] By reacting stilbene-modified phenol and ethylene oxide in a molar ratio of 1:18, nonionic surfactant B1-6, namely the ethylene oxide adduct of stilbene-modified phenol, is obtained.

[0131] (Nonionic surfactant B1-7)

[0132] Tristyrene-modified phenol, ethylene oxide, and propylene oxide were reacted in a molar ratio of 1:12:4 to obtain nonionic surfactant B1-7, which is a random adduct of ethylene oxide and propylene oxide of tristyrene-modified phenol.

[0133] (Nonionic surfactant B1-8)

[0134] Stilbene-modified phenol, ethylene oxide, and propylene oxide were reacted in a molar ratio of 1:10:6 to obtain nonionic surfactant B1-8, which is a random adduct of stilbene-modified phenol in ethylene oxide and propylene oxide.

[0135] (Nonionic surfactant B-9)

[0136] Dodecyl alcohol and ethylene oxide were reacted in a molar ratio of 1:7 to obtain nonionic surfactant B-9, which is an ethylene oxide adduct of dodecyl alcohol.

[0137] (Nonionic surfactant B-10)

[0138] Isododecyl alcohol and ethylene oxide were reacted in a molar ratio of 1:12 to obtain nonionic surfactant B-10, which is an ethylene oxide adduct of isododecyl alcohol.

[0139] (Nonionic surfactant B-11)

[0140] Tetradecyl alcohol and ethylene oxide were reacted in a molar ratio of 1:9 to obtain nonionic surfactant B-11, which is an ethylene oxide adduct of tetradecyl alcohol.

[0141] (Nonionic surfactant B-12)

[0142] Tridecanol and ethylene oxide were reacted at a molar ratio of 1:15 to obtain nonionic surfactant B-12, which is an ethylene oxide adduct of tridecanol.

[0143] (Nonionic surfactant B-13)

[0144] The reaction of dodecyl alcohol and ethylene oxide in a molar ratio of 1:12 yields nonionic surfactant B-13, which is an ethylene oxide adduct of dodecyl alcohol.

[0145] (Nonionic surfactant B-14)

[0146] The reaction of tert-tridecyl alcohol and ethylene oxide in a molar ratio of 1:7 yields nonionic surfactant B-14, which is the ethylene oxide adduct of tert-tridecyl alcohol.

[0147] (Nonionic surfactant B-15)

[0148] 2-Ethylhexanol, ethylene oxide, and propylene oxide were reacted in a molar ratio of 1:2:6 to obtain nonionic surfactant B-15, which is the random adduct of 2-ethylhexanol to ethylene oxide and propylene oxide.

[0149] (Nonionic surfactant B-16)

[0150] By reacting oleyl alcohol and ethylene oxide in a molar ratio of 1:15, nonionic surfactant B-16, namely the ethylene oxide adduct of oleyl alcohol, is obtained.

[0151] (Nonionic surfactant B-17)

[0152] Isononol and ethylene oxide were reacted in a molar ratio of 1:10 to obtain nonionic surfactant B-17, which is an ethylene oxide adduct of isononol.

[0153] (1-3) Resin

[0154] The resins shown below are used. These resins all conform to the resin (C) of the above-described embodiments. In addition, resins C1-1 to C1-11 conform to the thermosetting resin (C1) of the above-described embodiments, and resins C2-1 to C2-5 conform to the polyester resin (C2) of the above-described embodiments.

[0155] (Resin C1-1)

[0156] Epoxy resin jER (registered trademark) 828 manufactured by Mitsubishi Chemical Corporation.

[0157] (Resin C1-2)

[0158] Epoxy resin jER (registered trademark) 1001 manufactured by Mitsubishi Chemical Corporation.

[0159] (Resin C1-3)

[0160] Epoxy resin jER (registered trademark) 1002 manufactured by Mitsubishi Chemical Corporation.

[0161] (Resin C1-4)

[0162] Epoxy resin jER (registered trademark) 1004 manufactured by Mitsubishi Chemical Corporation.

[0163] (Resin C1-5)

[0164] NPES301 epoxy resin manufactured by Nan Ya Plastics Industrial Co., Ltd.

[0165] (Resin C1-6)

[0166] NPES302 epoxy resin manufactured by Nan Ya Plastics Industrial Co., Ltd.

[0167] (Resin C1-7)

[0168] SUMI-EPOXY (registered trademark) ELM-434 epoxy resin manufactured by Sumitomo Chemical Co., Ltd.

[0169] (Resin C1-8)

[0170] SUMI-EPOXY (registered trademark) ELM-100 epoxy resin manufactured by Sumitomo Chemical Co., Ltd.

[0171] (Resin C1-9)

[0172] A vinyl ester resin is obtained by reacting epoxy resin (jER (registered trademark) 828 manufactured by Mitsubishi Chemical Corporation) and methacrylic acid (MAA manufactured by Mitsubishi Chemical Corporation) in an equimolar ratio of epoxy value of epoxy resin to acid value of methacrylic acid.

[0173] (Resin C1-10)

[0174] A vinyl ester resin is obtained by reacting epoxy resin (jER (registered trademark) 828 manufactured by Mitsubishi Chemical Corporation) and methacrylic acid (MAA manufactured by Mitsubishi Chemical Corporation) in an amount ratio in which the epoxy value of the epoxy resin is 15% higher than the acid value of the methacrylic acid.

[0175] (Resin C1-11)

[0176] A vinyl ester resin is obtained by reacting epoxy resin (jER (registered trademark) 834 manufactured by Mitsubishi Chemical Corporation) and methacrylic acid (MAA manufactured by Mitsubishi Chemical Corporation) in an equimolar ratio of epoxy value of epoxy resin to acid value of methacrylic acid.

[0177] (Resin C2-1)

[0178] A polyester resin with a weight-average molecular weight of 10,000 is a copolymer of diethylene glycol (50 mol%), sodium 5-sulfoisophthalate (4 mol%), and isophthalic acid (46 mol%).

[0179] (Resin C2-2)

[0180] A polyester resin with a weight-average molecular weight of 15,000 is a copolymer of ethylene glycol (20 mol%), diethylene glycol (30 mol%), sodium 5-sulfoisophthalate (3 mol%), isophthalic acid (17 mol%), and terephthalic acid (30 mol%).

[0181] (Resin C2-3)

[0182] A polyester resin is obtained by reacting bisphenol A ethylene oxide adduct (NEWPOL (registered trademark) BPE-20 manufactured by Sanyo Chemical Industry Co., Ltd.) with fumaric acid in a ratio of 5:4 of hydroxyl value of bisphenol A ethylene oxide adduct to acid value of fumaric acid.

[0183] (Resin C2-4)

[0184] A polyester resin is obtained by reacting bisphenol A ethylene oxide adduct (NEWPOL (registered trademark) BPE-40 manufactured by Sanyo Chemical Industry Co., Ltd.) with fumaric acid in a ratio of 4:3 of hydroxyl value of bisphenol A ethylene oxide adduct to acid value of fumaric acid.

[0185] (Resin C2-5)

[0186] A polyester resin is obtained by reacting bisphenol A ethylene oxide adduct (NEWPOL (registered trademark) BPE-100 manufactured by Sanyo Chemical Industry Co., Ltd.) with fumaric acid in a ratio of 6:5 of hydroxyl value of bisphenol A ethylene oxide adduct to acid value of fumaric acid.

[0187] (1-4) Other components

[0188] The following compounds are used as other ingredients:

[0189] D-1: Octyl palmitate

[0190] D-2: Sodium alkyl sulfonate with 12-15 carbon atoms

[0191] Diluent: Ion-exchanged water

[0192] (2) Preparation of sizing agent

[0193] Weigh the following raw materials: 10 parts by mass of hydrocarbon A-1, 5 parts by mass of hydrocarbon A-13, 20 parts by mass of nonionic surfactant B1-1, 10 parts by mass of nonionic surfactant B1-2, 40 parts by mass of resin C1-1, and 15 parts by mass of resin C2-1. Mix and stir the weighed raw materials at 80°C, while slowly adding 300 parts by mass of deionized water as a diluent over 5 hours to obtain the sizing agent of Example 1.

[0194] (Examples 2-30 and Comparative Examples 1-3)

[0195] Except for the raw materials used, which are those listed in Tables 1 to 4 below, the sizing agents of Examples 2 to 30 and Comparative Examples 1 to 3 were obtained by the same method as in Example 1.

[0196] [Evaluation of sizing agents]

[0197] Each of the Examples and Comparative Examples was evaluated using the following steps. However, carbon fiber and glass fiber were used as the fiber materials for evaluating the sizing agent. Both carbon fiber and glass fiber were commercially available resin-reinforcing fiber materials. The types of reinforcing fibers used in each example evaluation are shown in the "Reinforcing Fiber" column of Tables 1 to 4, where carbon fiber is labeled "CF" and glass fiber is labeled "GF".

[0198] (1) Clustering

[0199] The fiber material (carbon fiber or glass fiber) was sized by applying sizing agent to a sizing bath filled with the sizing agents used in the examples and comparative examples. The amount of sizing agent applied was 1.5% of the weight of the fiber material. The sized fiber material roll was placed on a roving and unwound at a speed of 5 m / min. The state of the fiber material immediately after unwinding and passing through the roller was observed. Based on the observation results, the fiber material bundle properties resulting from the sizing agents in the examples and comparative examples were evaluated on a scale of A to C.

[0200] A: The fiber material wrapped around the roller is almost invisible, and the fiber material passing through is well gathered.

[0201] B: Although a small amount of fiber material is seen wrapped around the roller, the fiber material passing through is well gathered.

[0202] C: There is a lot of fiber material wrapped around the roller, and you can see that some of the fiber material is scattered as it passes through.

[0203] Here, whether the fiber material is well-gathered is judged by visual observation based on whether there are any fibers scattered with gaps visible in the fiber bundle.

[0204] (2) Post-storage napping

[0205] Fiber material (carbon fiber or glass fiber) with 3000 monofilaments was sized by applying sizing agent to a sizing bath filled with the sizing agents used in the examples and comparative examples. The sized fiber material was then wound into a roll. The amount of sizing agent applied was 1.5% of the fiber material weight. The wound fiber material roll was stored at room temperature for two months. The stored fiber material roll was placed on a roving creel and unwound at a speed of 5 m / min. Immediately after unwinding, the fiber material was inserted into the gap of a pre-measured weight of sponge, with a contact length of 5 cm, so that the resulting fluff adhered to the sponge. After 15 minutes, the sponge was removed and its weight was measured. The weight of the fluff adhering to the sponge was determined by comparing the measured weight with the pre-measured weight. In addition, the fiber material after passing through the sponge was used for fiber winding to observe its processability. Based on the weight of the fluff attached to the sponge and the processability of the fiber winding process, the effect of the sizing agents in the examples and comparative examples on preventing the fiber materials from pilling after storage was evaluated on a five-level scale from A to E.

[0206] A: The weight of the fluff attached to the sponge is less than 10mg, and the fiber winding process proceeds smoothly.

[0207] B: The weight of the fluff attached to the sponge is more than 10mg and less than 20mg, and the fiber winding process proceeds smoothly.

[0208] C: The weight of the fluff attached to the sponge is more than 20mg and less than 30mg, and the fiber winding process proceeds smoothly.

[0209] D: The weight of the fluff attached to the sponge is more than 30mg and less than 50mg, and the level is such that there is no obstacle to the operation of fiber winding processing.

[0210] E: The weight of the fluff attached to the sponge is more than 50mg, and obstacles to the fiber entanglement processing operation are observed.

[0211] (3) Adhesion

[0212] Epoxy resin or vinyl ester resin was used as the matrix resin for evaluating adhesion. When using epoxy resin, a mixture of epoxy resin (epoxy equivalent 190, jER (registered trademark) 828 manufactured by Mitsubishi Chemical Corporation) and BF3 monoethylamine salt (boron trifluoride monoethylamine manufactured by Stella Chemifa Corporation) in a mass ratio of 100:3 was used as the matrix resin. When using vinyl ester resin, Ripoxy (registered trademark) R-804B manufactured by Showa Denko Corporation, cured using methyl ethyl ketone peroxide curing agent manufactured by Showa Denko Corporation, was used as the matrix resin.

[0213] A sizing solution (2% concentration of non-volatile components) containing the sizing agents of the examples and comparative examples was prepared, and the fiber material (carbon fiber or glass fiber) was immersed in the sizing solution to adhere the sizing agent. The amount of sizing agent adhered was 2% relative to the weight of the fiber material. A fiber material was taken from the fiber material with the sizing agent attached. The two ends of the fiber material were fixed to a square frame-shaped support with an adhesive to keep the fiber material under tension. The matrix resin was adhered to the fiber material in resin droplet particles with a diameter of about 70 μm. The fiber material and the matrix resin were bonded together by heating in an air atmosphere at 160°C for a specified time to prepare a test piece. When the matrix resin was epoxy resin, the specified time was 90 minutes; when the matrix resin was vinyl ester resin, the specified time was 20 minutes. It should be noted that the types of matrix resins used in the evaluation of each example are shown in the "Matrix Resin" column of Tables 1 to 4. In this column, epoxy resin is listed as "EP" and vinyl ester resin is listed as "VE".

[0214] Each test piece was clamped between two blades, which moved along the fiber axis at a speed of 5 mm per minute. The maximum stress F generated when the resin droplets were peeled from the fiber material by these blades was measured using a load cell. The interfacial shear strength (IFSS) τ was calculated using Equation (1) based on the measured value. For each example and comparative example, the interfacial shear strength τ (unit: MPa) was calculated 20 times according to the above steps, and the average value was taken as the result.

[0215]

[0216] In formula (1), F is the maximum stress generated when the resin droplets are peeled from the carbon fiber (unit: kgf), D is the diameter of the carbon fiber used as the test piece (unit: mm), and L is the diameter of the resin droplets in the test piece along the fiber axis (unit: mm).

[0217] Based on the obtained interfacial shear strength τ value, the adhesiveness of the sizing agents in the Examples and Comparative Examples was evaluated on a four-level scale, A to D. It should be noted that the "reference value" in the following descriptions is 60 MPa when the base resin is epoxy resin and 40 MPa when the base resin is vinyl ester resin.

[0218] A: The interfacial shear strength τ is more than 1.30 times the benchmark value.

[0219] B: The interfacial shear strength τ is more than 1.12 times and less than 1.30 times the reference value.

[0220] C: The interfacial shear strength τ is greater than 1.01 times and less than 1.12 times the reference value.

[0221] D: The interfacial shear strength τ is less than 1.01 times the reference value.

[0222] [result]

[0223] The raw material composition, fiber materials (carbon fiber or glass fiber) used in the evaluation, and evaluation results of each of the examples and comparative examples are shown in Tables 1 to 4.

[0224] Table 1: Evaluation Results of Sizing Agents (Examples)

[0225]

[0226] Table 2: Evaluation Results of Sizing Agents (Examples)

[0227]

[0228] Table 3: Evaluation Results of Sizing Agents (Examples)

[0229]

[0230] Table 4: Evaluation Results of Sizing Agents (Comparative Examples)

[0231]

[0232] Industrial Applicability: This invention can be used, for example, for sizing of fibrous materials.

Claims

1. A sizing agent for reinforcing fibers, characterized in that, It contains one or more hydrocarbons (A) selected from mineral oil, liquid paraffin and polyalphaolefins that are liquid at room temperature, and a nonionic surfactant (B), wherein the proportion of the hydrocarbons (A) in the non-volatile component is more than 0% by mass and less than 50% by mass.

2. The sizing agent for reinforcing fibers as described in claim 1, wherein, The hydrocarbon (A) contains a polyalphaolefin as a 3- to 8-mer of 1-decene.

3. The sizing agent for reinforcing fibers as described in claim 1, wherein, The hydrocarbon (A) contains mineral oil, wherein the aromatic content of the mineral oil is more than 0% by mass and less than 5% by mass.

4. The sizing agent for reinforcing fibers as described in claim 1, wherein, It contains mineral oil and polyalphaolefin as the hydrocarbon (A).

5. The sizing agent for reinforcing fibers as described in claim 1, wherein, An epoxide adduct containing an aromatic alcohol (B1) is used as the nonionic surfactant (B).

6. The sizing agent for reinforcing fibers as described in claim 1, wherein, It also contains one or more resins (C) selected from thermosetting resins (C1) and polyester resins (C2).

7. The sizing agent for reinforcing fibers as described in claim 6, wherein, The resin (C) contains a thermosetting resin (C1).

8. The sizing agent for reinforcing fibers as described in claim 6, wherein, The resin (C) contains a thermosetting resin (C1) and a polyester resin (C2).

9. The sizing agent for reinforcing fibers as described in claim 6, wherein, Relative to the total mass of the hydrocarbon (A), the nonionic surfactant (B), and the resin (C), The hydrocarbon (A) comprises 0.1% by mass or more and less than 50% by mass. The nonionic surfactant (B) comprises 0.1% by mass or more and 50% by mass or less. The resin (C) has a mass percentage of more than 20% and less than 90% by mass.

10. A reinforcing fiber, characterized in that, A sizing agent for reinforcing fibers, as described in any one of claims 1 to 9, is attached.

11. The reinforcing fiber as claimed in claim 10, wherein, It is an inorganic fiber with a sizing agent for reinforcing fibers attached to it.

12. The reinforcing fiber as claimed in claim 11, wherein, The inorganic fiber is carbon fiber or glass fiber.

13. A composite material, characterized in that, It comprises the reinforcing fiber as described in claim 12 and the matrix resin as a thermosetting resin.

Images