阅读说明：本技术 由碳纤维强化热塑性树脂构成的片材和该片材的制造方法 (Sheet material comprising carbon fiber-reinforced thermoplastic resin and method for producing the sheet material ) 是由 杉山源希 吉谷耕平 清水英贵 丸山博义 于 2018-05-14 设计创作，主要内容包括：本发明的课题在于提供一种能够简化制造工序、由机械特性优异的碳纤维强化热塑性树脂构成的片材以及该片材的制造方法。该课题能够通过由包含热塑性树脂、碳纤维和二氯甲烷的碳纤维强化热塑性树脂构成的片材得到解决,该热塑性树脂含有聚碳酸酯树脂和聚芳酯树脂中的至少一种,上述片材中所含的上述二氯甲烷的含量为10～10,000质量ppm。(The invention provides a sheet material composed of carbon fiber reinforced thermoplastic resin with excellent mechanical properties and capable of simplifying the manufacturing process, and a manufacturing method of the sheet material. The problem can be solved by a sheet material composed of a carbon fiber reinforced thermoplastic resin containing a thermoplastic resin, carbon fibers and methylene chloride, wherein the thermoplastic resin contains at least one of a polycarbonate resin and a polyarylate resin, and the methylene chloride is contained in the sheet material in an amount of 10 to 10,000 mass ppm.)

1. A sheet material, characterized in that,

comprising a carbon fiber-reinforced thermoplastic resin containing a thermoplastic resin, carbon fibers and methylene chloride,

the thermoplastic resin contains at least one of a polycarbonate resin and a polyarylate resin,

the content of the methylene chloride contained in the sheet is 10 to 10,000 mass ppm.

2. The sheet of claim 1,

the carbon fibers are continuous fibers.

3. The sheet according to claim 1 or 2,

the carbon fiber is contained in an amount of 20 to 80 vol%, and the thermoplastic resin is contained in an amount of 80 to 20 vol%.

4. The sheet according to any one of claims 1 to 3,

the viscosity average molecular weight of the polycarbonate resin and the polyarylate resin is 10,000-100,000.

5. A laminated sheet obtained by directly laminating the sheet according to any one of claims 1 to 4.

6. The laminated sheet of claim 5,

without a sheet containing no carbon fibers.

7. A method for producing a carbon fiber-reinforced thermoplastic resin sheet, comprising:

a step for producing a thermoplastic resin solution in which a thermoplastic resin containing at least one of a polycarbonate resin and a polyarylate resin is dissolved in methylene chloride by an interfacial polymerization method;

impregnating the carbon fibers with the thermoplastic resin solution; and

and volatilizing the methylene chloride from the carbon fiber impregnated with the thermoplastic resin solution.

8. The manufacturing method according to claim 7,

the concentration of the polycarbonate resin and the polyarylate resin in the thermoplastic resin solution is 10 to 30 mass%.

Technical Field

The present invention relates to a sheet material made of a carbon fiber-reinforced thermoplastic resin suitable for use in aircraft parts, spacecraft parts, automobile parts, ship parts, electronic device parts, sports-related parts, and the like, and a method for producing the sheet material.

Background

Carbon fibers, glass fibers, and aramid fibers are excellent in elastic modulus and strength despite their low specific gravity compared to metals, and thus composite materials combining them with various matrix resins are used in many fields such as aircraft parts, spacecraft parts, automobile parts, marine parts, civil engineering and construction materials, and sporting goods. In particular, carbon fiber reinforced resin (CFRP) is widely used as a composite material in which carbon fibers are combined with an epoxy resin or an unsaturated polyester resin.

Although conventional carbon fiber reinforced resins having a thermosetting resin as a matrix have a drawback that long time is required for thermosetting, in recent years, carbon fiber reinforced thermoplastic resins (hereinafter sometimes referred to as "CFRTP") having a thermoplastic resin as a matrix have been expected as composite materials capable of realizing high cycle molding, and development thereof has been made.

Short fiber-reinforced thermoplastic resins capable of molding into complicated shapes have been put to practical use, but since the fiber length of the reinforcing fibers is short, there is a problem that the elastic modulus is significantly lower than that of light metals. Therefore, continuous fiber reinforced thermoplastic resins are strongly demanded.

Patent document 1 discloses a method for producing a glass fiber fabric-reinforced polycarbonate resin molded article, in which a resin-impregnated sheet obtained by removing a solvent from a glass fiber fabric impregnated with a polycarbonate resin solution and a laminate of the resin-impregnated sheet and a polycarbonate resin film are heated and pressed, but further improvement in mechanical properties is required.

Disclosure of Invention

Problems to be solved by the invention

The invention provides a sheet material composed of carbon fiber reinforced thermoplastic resin with excellent mechanical properties and capable of simplifying the manufacturing process, and a manufacturing method of the sheet material.

Means for solving the problems

As a result of intensive studies to solve the above problems, the inventors of the present invention have found that a sheet made of a carbon fiber-reinforced thermoplastic resin having excellent mechanical properties can be obtained by simplifying the production process by using a resin containing a predetermined amount of methylene chloride by an interfacial polymerization method, and have completed the present invention. That is, the above problem can be solved by the following invention.

< 1 > a sheet comprising a carbon fiber-reinforced thermoplastic resin comprising a thermoplastic resin, carbon fibers and methylene chloride, wherein the thermoplastic resin contains at least one of a polycarbonate resin and a polyarylate resin, and the methylene chloride is contained in the sheet in an amount of 10 to 10,000 ppm by mass.

< 2 > the sheet as stated above < 1 >, wherein the above carbon fiber is a continuous fiber.

The sheet material is < 3 > as described above < 1 > or < 2 >, wherein the sheet material contains 20 to 80 vol% of the carbon fiber and 80 to 20 vol% of the thermoplastic resin.

< 4 > the sheet according to any one of the above < 1 > to < 3 >, wherein the polycarbonate resin and the polyarylate resin have a viscosity average molecular weight of 10,000 to 100,000.

< 5 > a laminated sheet obtained by directly laminating the sheet described in any one of < 1 > -to < 4 >.

< 6 > the laminated sheet as stated above < 5 > wherein there is no sheet containing no carbon fiber.

< 7 > a method for producing a carbon fiber-reinforced thermoplastic resin sheet, which comprises:

a step for producing a thermoplastic resin solution in which a thermoplastic resin containing at least one of a polycarbonate resin and a polyarylate resin is dissolved in methylene chloride by an interfacial polymerization method;

impregnating the carbon fibers with the thermoplastic resin solution; and

and volatilizing the methylene chloride from the carbon fiber impregnated with the thermoplastic resin solution.

< 8 > the production method according to the above < 7 >, wherein the concentration of the polycarbonate resin and the polyarylate resin in the thermoplastic resin solution is 10 to 30% by mass.

Effects of the invention

According to the present invention, a sheet made of a carbon fiber-reinforced thermoplastic resin having excellent mechanical properties, which can be produced in a simplified process, and a method for producing the sheet are provided.

Detailed Description

The present invention will be described in detail below by way of examples of production examples and examples, but the present invention is not limited to the examples of production and examples, and can be carried out by changing to any method without significantly departing from the scope of the present invention.

The sheet is a sheet composed of a carbon fiber-reinforced thermoplastic resin containing a thermoplastic resin, carbon fibers and methylene chloride, wherein the thermoplastic resin contains at least one of a polycarbonate resin and a polyarylate resin, and the methylene chloride is contained in the sheet in an amount of 10 to 10,000 ppm by mass.

< carbon fiber >

The carbon fiber used in the present invention is preferably a continuous fiber. The fiber length of the continuous fibers is preferably 10mm or more on average, and more preferably 30mm or more. Examples of the form of the continuous fibers include unidirectional sheets, woven sheets, multiaxial laminated sheets, and the like.

The number of single fibers contained in a fiber bundle (filament), the number of filaments contained in a filament bundle (tow), and their structures are various according to the carbon fiber, and in the present invention, the number of short fibers, the number of filaments, and their structures are not limited, and various carbon fibers can be used.

The proportion of the carbon fibers in the carbon fiber-reinforced thermoplastic resin in the present invention is preferably 20 to 80 vol%, more preferably 30 to 70 vol%, and still more preferably 40 to 60 vol%, from the viewpoint of mechanical properties of the carbon fiber-reinforced thermoplastic resin.

< thermoplastic resin >

At least one of the polycarbonate resin and the polyarylate resin contained in the thermoplastic resin used in the present invention has a structural unit derived from a dihydric phenol represented by the following general formula (1), and both a homopolymer and a copolymer can be used.

(in the general formula (1), R₁～R₄Each independently represents hydrogen, halogen, nitro, an alkyl group having 1 to 20 carbon atoms which may have a substituent, an alkoxy group having 1 to 5 carbon atoms which may have a substituent, an aryl group having 6 to 12 carbon atoms which may have a substituent, an aralkyl group having 7 to 17 carbon atoms which may have a substituent, or an alkenyl group having 2 to 15 carbon atoms which may have a substituent;

x is-O-, -S-, -SO₂-, -CO-or a divalent group represented by any one of the following formulae (2) to (5). )

In the formula (2), R₅And R₆Each independently represents hydrogen, halogen, an alkyl group having 1 to 20 carbon atoms which may have a substituent, an alkoxy group having 1 to 5 carbon atoms which may have a substituent, an aryl group having 6 to 12 carbon atoms which may have a substituent, an aralkyl group having 7 to 17 carbon atoms which may have a substituent, or an alkenyl group having 2 to 15 carbon atoms which may have a substituentOr R is₅And R₆Can be bonded to each other to form a carbon ring having 3 to 20 carbon atoms or a heterocyclic ring having 1 to 20 carbon atoms.

From the viewpoint of easiness of raw material acquisition, R is preferably₅Represents an alkyl group having 1 to 3 carbon atoms or an aryl group having 6 to 12 carbon atoms.

From the viewpoint of easiness of raw material acquisition, R is preferably₆Represents an alkyl group having 1 to 3 carbon atoms or an aryl group having 6 to 12 carbon atoms.

In addition, from the viewpoint of easiness of acquisition of raw materials, R is preferable₅And R₆Are bonded to each other to form a carbon ring having 6 to 12 carbon atoms.

c represents an integer of 0 to 20, and preferably represents 1 or 2 from the viewpoint of easiness of raw material acquisition.

In the formula (3), R₇And R₈Each independently represents hydrogen, halogen, an alkyl group having 1 to 20 carbon atoms which may have a substituent, an alkoxy group having 1 to 5 carbon atoms which may have a substituent, an aryl group having 6 to 12 carbon atoms which may have a substituent, an aralkyl group having 7 to 17 carbon atoms which may have a substituent, an alkenyl group having 2 to 15 carbon atoms which may have a substituent, or R₇And R₈Are bonded to each other to form a carbon ring having 3 to 20 carbon atoms or a heterocyclic ring having 1 to 20 carbon atoms.

From the viewpoint of easiness of raw material acquisition, R is preferably₇Represents hydrogen or methyl.

From the viewpoint of easiness of raw material acquisition, R is preferably₈Represents hydrogen or methyl.

In addition, from the viewpoint of easiness of acquisition of raw materials, R is preferable₇And R₈Are bonded to each other to form a carbon ring having 5 to 12 carbon atoms.

In the formula (4), R₉～R₁₂Each independently represents: hydrogen, halogen, an alkyl group having 1 to 20 carbon atoms, preferably 1 to 9 carbon atoms which may have a substituent, an alkoxy group having 1 to 5 carbon atoms, preferably 1 to 3 carbon atoms which may have a substituent, an aryl group having 6 to 12 carbon atoms, preferably 6 to 8 carbon atoms which may have a substituent, and the likeAn aralkyl group having 7 to 17 carbon atoms, preferably 7 to 12 carbon atoms, which may have a substituent, or an alkenyl group having 2 to 15 carbon atoms, preferably 2 to 5 carbon atoms, which may have a substituent. The substituent may be halogen, alkyl having 1 to 20 carbon atoms, or aryl having 6 to 12 carbon atoms. In addition, R₉And R₁₀And R₁₁And R₁₂Can be bonded to each other to form a carbon ring having 3 to 20 carbon atoms or a heterocyclic ring having 1 to 20 carbon atoms.

In the formula (5), R₁₃～R₂₂Each independently represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, R₁₃～R₂₂At least one of the above groups is an alkyl group having 1 to 3 carbon atoms.

From the viewpoint of easiness of raw material acquisition, R is preferably₁₃～R₂₂Each independently represents hydrogen or methyl.

Examples of the dihydric phenol of the general formula (1) include: 2, 2-bis (4-hydroxyphenyl) propane [ (═ bisphenol a ], bis (4-hydroxyphenyl) p-diisopropylbenzene, 4' -dihydroxybiphenyl, 2-bis (4-hydroxy-3, 5-dimethylphenyl) propane, 2-bis (4-hydroxy-3-methylphenyl) propane, 2-bis (4-hydroxy-3, 5-diethylphenyl) propane, 2-bis (4-hydroxy-3-ethylphenyl) propane, 2-bis (4-hydroxy-3, 5-diphenylphenyl) propane, 2-bis (4-hydroxy-3-phenylphenyl) propane, 2-bis (4-hydroxy-3, 5-dibromophenyl) propane, 2-bis (4-hydroxy-3-bromophenyl) propane, 2-bis (4-hydroxyphenyl) pentane, 2,4' -dihydroxy-diphenylmethane, 4' -dihydroxydiphenyl methane, Bis- (4-hydroxy-3-methylphenyl) methane, bis- (4-hydroxy-3-nitrophenyl) methane, 1-bis (4-hydroxyphenyl) ethane, 1-bis (4-hydroxy-3-methylphenyl) ethane, 3-bis (4-hydroxyphenyl) pentane, 1-bis (4-hydroxyphenyl) cyclohexane [ ═ bisphenol Z ], bis (4-hydroxyphenyl) sulfone, 2,4' -dihydroxydiphenylsulfone, bis (4-hydroxyphenyl) sulfide, 4' -dihydroxydiphenyl ether, 4' -dihydroxy-3, 3' -dimethyldiphenyl ether, 4' -dihydroxy-2, 5-diethoxydiphenyl ether, 1-phenyl-1, 1-bis (4-hydroxyphenyl) ethane, 1-bis (4-hydroxy-3-methylphenyl) cyclohexane, 1-phenyl-1, 1-bis (4-hydroxy-3-methylphenyl) ethane, 1-bis (4-hydroxyphenyl) ethane, 1-bis (4-hydroxy-3-hydroxyphenyl) ethane, 1, bis (4-hydroxyphenyl) diphenylmethane, bis (4-hydroxy-3-methylphenyl) diphenylmethane, 9-bis (4-hydroxyphenyl) fluorene, 9-bis (4-hydroxy-3-methylphenyl) fluorene, 2-bis (4-hydroxyphenyl) hexafluoropropane, and the like. Bis (4-hydroxyphenyl) alkanes are preferred, and 2, 2-bis (4-hydroxyphenyl) propane [ bisphenol A ] is particularly preferred. These aromatic dihydroxy compounds may be used alone or in combination of 2 or more.

The viscosity average molecular weight of the polycarbonate resin used in the present invention is preferably 10,000 to 100,000, more preferably 14,000 to 60,000, and even more preferably 16,000 to 40,000, from the viewpoint of the solution viscosity which facilitates handling in the state of a resin solution.

The viscosity average molecular weight of the polyarylate resin used in the present invention is preferably 10,000 to 100,000, more preferably 14,000 to 60,000, and even more preferably 16,000 to 40,000, from the viewpoint of a solution viscosity that facilitates handling in a state of a resin solution.

The thermoplastic resin may contain a component other than at least one of the polycarbonate resin and the polyarylate resin, and other resins, and various additives such as a mold release agent, a flame retardant, an antioxidant, a heat stabilizer, a flame retardant aid, an ultraviolet absorber, a colorant, an antistatic agent, a fluorescent whitening agent, an antifogging agent, a flowability improver, a plasticizer, a dispersant, and an antibacterial agent may be blended as long as the effects of the present invention can be exhibited.

Examples of other resins include: thermoplastic polyester resins such as polyethylene terephthalate resin (PET resin), polytrimethylene terephthalate resin (PTT resin), and polybutylene terephthalate resin (PBT resin); styrene resins such AS polystyrene resin (PS resin), high impact polystyrene resin (HIPS), acrylonitrile-styrene copolymer (AS resin), and methyl methacrylate-styrene copolymer (MS resin); core/shell elastomers such as methyl methacrylate-acrylic rubber-styrene copolymer (MAS), and elastomers such as polyester elastomers; polyolefin resins such as cyclic cycloolefin resin (COP resin) and cyclic Cycloolefin (COP) copolymer resin; polyamide resin (PA resin); polyimide resin (PI resin); polyetherimide resins (PEI resins); a polyurethane resin (PU resin); polyphenylene ether resin (PPE resin); polyphenylene sulfide resin (PPS resin); polysulfone resin (PSU resin); polymethacrylate resin (PMMA resin); polycaprolactone, and the like.

The proportion of these components in 100% by mass of the thermoplastic resin is preferably 0 to 50% by mass, and more preferably 0 to 20% by mass.

< methylene chloride >

The sheet of the present invention is characterized in that the content of methylene chloride contained in the sheet is 10 to 10,000 mass ppm. The content of methylene chloride in the sheet is preferably 10 to 5,000 mass ppm, more preferably 10 to 1,000 mass ppm. When the content of methylene chloride exceeds 10,000 mass ppm, when the sheet of the present invention is subjected to heat processing by press molding or the like, there may be cases where methylene chloride is contained, and gas is generated during heat processing, or appearance defects (voids) of the sheet after heat processing occur.

The method for measuring the content of methylene chloride contained in the sheet of the present invention is described in examples below.

In the present invention, as a method for obtaining a sheet having a good appearance by adjusting the content of methylene chloride contained in the sheet to 10 to 10,000 mass ppm, for example: in the step of volatilizing methylene chloride from the carbon fiber impregnated with the thermoplastic resin solution in which the thermoplastic resin containing at least one of the polycarbonate resin and the polyarylate resin is dissolved in methylene chloride, the drying temperature and the drying time are adjusted. Specifically, it is preferable to evaporate methylene chloride to a certain extent by drying without external heating or with little external heating, for example, by air drying, and then to perform external heating and drying. The air-drying may be performed only at room temperature, or may be accelerated by blowing air.

< carbon fiber-reinforced thermoplastic resin >

The ratio of the carbon fiber to the thermoplastic resin in the carbon fiber-reinforced thermoplastic resin in the present invention is preferably 20 to 80 vol% for the carbon fiber and 80 to 20 vol% for the thermoplastic resin, and from the viewpoint of mechanical strength of the carbon fiber-reinforced thermoplastic resin, more preferably 30 to 70 vol% for the carbon fiber, 70 to 30 vol% for the thermoplastic resin, even more preferably 40 to 60 vol% for the carbon fiber, and 60 to 40 vol% for the thermoplastic resin.

When the proportion of the carbon fibers is less than the above range, the mechanical properties of the carbon fiber-reinforced thermoplastic resin are equal to or less than those of light metals; when the proportion of the carbon fibers is more than this range, the amount of the resin is small, and the carbon fibers cannot be bundled by the matrix resin, which may result in a decrease in mechanical strength.

The carbon fiber-reinforced thermoplastic resin in the present invention may contain components other than carbon fibers, thermoplastic resin and methylene chloride. Examples of these components include other resins, and various additives such as mold release agents, flame retardants, antioxidants, heat stabilizers, flame retardant aids, ultraviolet absorbers, colorants, antistatic agents, fluorescent whitening agents, antifogging agents, flowability improvers, plasticizers, dispersants, and antibacterial agents.

< sheet and laminated sheet >

The thickness of the sheet of the present invention is not particularly limited, but is preferably 0.01mm to 1mm, and more preferably 0.05mm to 0.5 mm.

The sheets of the present invention are preferably directly laminated to form a laminated sheet. Particularly, a laminated sheet having no sheet containing no carbon fiber is more preferable.

As a method for producing a laminated sheet by laminating the sheets of the present invention, a press molding method and the like can be mentioned.

< method for producing carbon fiber-reinforced thermoplastic resin >

The method for producing a carbon fiber-reinforced thermoplastic resin in the present invention comprises: a step for producing a thermoplastic resin solution in which a thermoplastic resin containing at least one of a polycarbonate resin and a polyarylate resin is dissolved in methylene chloride by an interfacial polymerization method; impregnating the carbon fibers with the thermoplastic resin solution; and volatilizing the methylene chloride from the carbon fiber impregnated with the thermoplastic resin solution.

In the production method of the present invention, the concentration of the polycarbonate resin in the thermoplastic resin solution is preferably 10 to 30% by mass, and more preferably 12 to 25% by mass. When the concentration of the polycarbonate resin is less than 10% by mass, foaming may occur during drying in the subsequent step; when the content is more than 30% by mass, the solution viscosity may be significantly increased, and the operation in the impregnation step may be difficult.

In the production method of the present invention, the concentration of the polyarylate resin in the thermoplastic resin solution is preferably 10 to 30% by mass, and more preferably 12 to 25% by mass. When the concentration of the polyarylate resin is less than 10% by mass, foaming may occur during drying in the subsequent step; when the content is more than 30% by mass, the solution viscosity may be significantly increased, and the operation in the impregnation step may be difficult.

(Process for producing thermoplastic resin solution)

In the reaction by the interfacial polymerization method, a polycarbonate resin solution is obtained by mixing reaction raw materials containing a dihydric phenol, a monohydric phenol as a chain terminator, an antioxidant for preventing oxidation of the dihydric phenol, which is used as needed, and phosgene or triphosgene as a carbonate binder, in the presence of methylene chloride and an aqueous alkali solution, usually at a pH of 10 or more, adding a polymerization catalyst such as a tertiary amine or a quaternary ammonium salt to conduct interfacial polymerization, and purifying the obtained resin solution. The addition of the chain terminator is not particularly limited as long as it is between the phosgenation and the initiation of the polymerization reaction. Wherein the reaction temperature is 0-35 ℃, and the reaction time is several minutes-several hours.

(impregnation step)

The impregnation step is a step of impregnating carbon fibers with a thermoplastic resin solution such as a polycarbonate resin solution. The impregnation method is not particularly limited, and various methods such as a method of immersing the fibers in a tank containing the solution, a method of passing the fibers through a tank in which the solution is sprayed, and a method of spraying the solution to the fibers can be employed. Among these, a method of immersing the fibers in a tank containing the solution is preferable because the solution can be adhered most easily and uniformly.

(volatilizing (drying) step)

And volatilizing methylene chloride from the carbon fiber impregnated with the thermoplastic resin solution such as a polycarbonate resin solution. It is preferable to evaporate methylene chloride to a certain extent by drying with no or little external heat, such as air drying, and then to perform external heat drying. The air-drying may be performed only at room temperature, or may be accelerated by blowing air.