JP2002249615A - Composite foam molded article, method for producing the same, and method for producing laminated molded article - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a composite foam molded article which is lightweight, has excellent mechanical strength, is relatively inexpensive and inexpensive, and can be suitably used as a core material for sports equipment. SOLUTION: A large number of cell structural units composed of a foam domain made of a polystyrene-based resin and a thin-walled hardened wall made of an epoxy resin-based cured material surrounding the foam domain are gathered without gaps, and the apparent appearance is increased. A composite foam molded article having a density of 0.1 to 0.5 g / cm ³ .

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lightweight and excellent mechanical strength plastic composite foamed molded article which is suitably used as a core material for sports equipment such as skis, snowboards, surfboards, sledboards, and the like. The present invention also relates to a method for producing a laminated molded product suitably used as the sports equipment.

[0002]

2. Description of the Related Art Conventionally, sports equipment such as skis, snowboards, surfboards, and sleds are required to have excellent mechanical strength and light weight. Therefore, a lightweight, high mechanical strength foam is used as a core material. There has been proposed a plate-shaped body having a configuration in which the periphery is surrounded by a reinforcing fiber material or the like which is further excellent in mechanical strength. For example, Japanese Patent Application Laid-Open No. 8-103528 discloses a ski having a structure in which a foamed material made of a tough epoxy resin is used as a core material and the periphery thereof is surrounded by a reinforcing fiber material.

However, since the ski described in the above-mentioned publication uses a foam containing an epoxy resin as a main component, the foaming time and the resin curing time are long, and it is difficult to adjust and control the process, and the productivity is low. There was a problem that I could not give. Furthermore, the epoxy resin is relatively expensive among general-purpose resins, and there has been a problem that the use of a large amount increases the cost.

As a method for solving the above-mentioned problem, a tough and versatile epoxy resin excellent in chemical resistance, weather resistance, and the like is currently mass-produced and is available inexpensively, such as polystyrene resin. It is conceivable to reduce the amount of epoxy resin used by using in combination with the foamed particles. However, although the polystyrene resin and the epoxy resin are excellent in compatibility, the polystyrene resin is often attacked by the epoxy resin, or the microcells of the foamed particles are often destroyed by heat at the time of curing. It was difficult to obtain a composite foam molded article.

[0005] As described above, in addition to the above-mentioned core materials for sports equipment, foamed particles of polystyrene resin and epoxy resin are used in various fields such as other building materials, civil engineering materials, marine materials, and housing equipment. In fact, a composite foamed molded article obtained by combining the above is desired from the viewpoint of both function and cost, but has not been obtained.

[0006]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned conventional plastic composite foamed molded articles, and has been considered to be difficult to composite. It is an object of the present invention to provide a composite foam molded article which is made of a product, is lightweight, has excellent mechanical strength, is relatively inexpensive and inexpensive, and can be suitably used as a core material for sports equipment. Another object of the present invention is to provide a manufacturing method capable of stably obtaining the above-mentioned composite foam molded article by a simple process. Still another object of the present invention is to provide a laminated molded article in which the composite foam molded article is sandwiched or surrounded by a hard plate-like body such as a reinforcing fiber material and can be suitably used as a sporting goods. An object of the present invention is to provide a production method that can be obtained stably in a process.

[0007]

Means for Solving the Problems The composite foamed molded article of the invention according to claim 1 of the present invention (hereinafter referred to as "the present invention 1") comprises: a foam domain comprising a polystyrene resin;
A large number of cell structural units composed of a thin cured wall of an epoxy resin-based cured material surrounding the foam domain are gathered without gaps, and have an apparent density of 0.1 to 0.5 g / cm ³ . There is a feature.

[0008] The invention according to claim 3 of the present invention (hereinafter referred to as "the invention")
In order to stably produce the composite foam molded article of the present invention 1 in a simple process, the viscosity of the epoxy resin is adjusted and mixed with a polystyrene resin. It has been completed under the knowledge that it is possible to produce the composite foam molded article, which has been considered difficult, and expandable particles made of a polystyrene resin,
A thermosetting epoxy resin-based composition having a viscosity of 0.1 to 100 Pa · s at a temperature 20 ° C. lower than the foaming temperature of the expandable particles, and a thermosetting epoxy resin-based composition having a viscosity of 0 The mixed raw material composition was mixed in a state of 1 to 100 Pa · s to obtain a mixed raw material composition, and the mixed raw material composition was heated to a foaming temperature of the expandable particles in a molding die to have an apparent density of 0.1 to 0.5.
The thermosetting epoxy resin composition is cured while the expandable particles are foamed so as to have a g / cm ³ .

[0009] The invention according to claim 6 of the present invention (hereinafter referred to as "the invention")
The "present invention 3") is a method capable of stably producing a laminated molded article such as sports equipment using the composite foam molded article of the present invention 1 as a core material in a simple process, Expandable particles made of a polystyrene resin and having a viscosity of 0.1 at a temperature 20 ° C. lower than the expansion temperature of the expandable particles.
A thermosetting epoxy resin composition in a state of 1 to 100 Pa · s is mixed with the thermosetting epoxy resin composition in a state of a viscosity of 0.1 to 100 Pa · s to form a mixed raw material composition, The mixed raw material composition and the hard plate-like body in a molding die, such that the mixed raw material composition is sandwiched between the hard plate-shaped bodies, or
After arranging the mixed raw material composition so as to surround the hard plate-like body, the mixture is heated to the expansion temperature of the expandable particles, and the expandable particles are heated to an apparent density of 0.1 to 0.5 g / cm ^3. It is characterized in that the thermosetting epoxy resin composition is cured while being foamed.

Hereinafter, the present inventions 1 to 3 will be described in order.
FIG. 1 is a view schematically showing a cross section of one embodiment of the composite foam molded article of the present invention 1. The composite foam molded article 1 has a cell structural unit 4 composed of a foam domain 2 and a hardened wall 3.
However, many gather without gaps.

Examples of the polystyrene resin constituting the foam domain used in the present invention 1 include polystyrene, a styrene-ethylene copolymer having a styrene component of 50% by weight or more, and a styrene component of 50% by weight or more. Styrene-maleic acid copolymers and the like are preferred, and these may be used alone or in combination of two or more. For example, polystyrene is inexpensive, foam domains composed of polystyrene have excellent mechanical strength, foam domains composed of styrene-ethylene copolymer have excellent impact resistance, and styrene-maleic acid copolymer has excellent mechanical strength. The foam domain composed of a polymer is more excellent in mechanical strength than the foam domain composed of the polystyrene, and it is preferable to appropriately select and adjust them according to physical properties, applications, and the like, which are regarded as important.

The shape of the form domain 2 is as follows.
Examples thereof include a polyhedral shape and a spherical shape, and are not particularly limited, and include a large number of bubbles 21 therein. The method for forming the foam domain is not particularly limited. For example, as in the present invention 2 described below, foamable particles are foamed in a mold, and a large number of foam domains are formed through a hardened wall without a gap under pressure. It is formed by aggregating. The three-dimensional shape of the cell membrane varies depending on the shape of the expandable particles as the raw material, the apparent density of the composite foam molded article, and is not particularly limited. It usually has a polyhedral shape close to a sphere, but may have directionality. For example, if a spindle shape in which the major axes are arranged in parallel in the thickness direction is used, mechanical strength can be increased.

When the size of the foam domain 2 is reduced, the outer surface area of the foam domain is increased, so that a large amount of epoxy resin-based cured material surrounding the foam domain is required, and the cost is increased. The average diameter is preferably from 1 to 10 mm, more preferably from 2 to 7 mm, because the mechanical strength of the molded body is likely to be locally reduced. The average diameter is a value measured by the following method. First, a photograph is taken of a cut surface of the composite foam molded article that is perpendicular to the thickness direction, and on the photograph,
The area is calculated for each of the cut surfaces of the 0 foam domains, and from the obtained areas S _{1 to} S ₁₀ , the respective diameters L ₁ to when the form domain cut surface is a perfect circle.
To calculate the L _10. Mean value of the obtained diameters L ₁ ~L ₁₀ is the average diameter of the foam domain.

The distance between adjacent foam domains is appropriately adjusted according to the required physical properties, applications, and the like. However, when the distance is small, the mechanical strength of the obtained composite foamed molded article is reduced, and when the distance is large, the mechanical strength is increased. Since the lightness of the resulting composite foam molded article is reduced, the thickness is preferably from 1 to 3000 μm. Note that the distance between adjacent form domains is the distance indicated by D in FIG.

The cured wall 3 used in the present invention 1 is made of an epoxy resin-based cured product, and preferably contains a particulate, fibrous or rod-like solid component. The epoxy resin-based cured product is mainly composed of an epoxy resin and a curing agent thereof, and is a thermosetting epoxy resin-based composition to which a curing accelerator or the like is added as necessary.

As the above epoxy resin, for example, bisphenol A type epoxy resin, brominated bisphenol A
Epoxy resin, hydrogenated bisphenol A epoxy resin, bisphenol F epoxy resin, cresol novolak epoxy resin, phenol novolak epoxy resin, alicyclic epoxy resin, heterocyclic epoxy resin, glycidyl ester epoxy resin, glycidyl Ether-type epoxy resin, glycidylamine-type epoxy resin, urethane-modified epoxy resin, rubber-modified epoxy resin, epoxidized elastomer, epoxidized stearic acid ester, epoxidized soybean oil, epoxy-modified polysiloxane, flexible epoxy resin, epoxidized ( Examples thereof include (meth) acrylic oligomers and reactive diluents having an epoxy group, and these may be used alone or in combination of two or more.

Examples of the curing agent include maleic anhydride, phthalic anhydride, hexahydrophthalic anhydride, tetrahydrophthalic anhydride, methylhymic anhydride, methylCD anhydride, methylnadic anhydride, pyromellitic anhydride, Acid anhydride-based hardeners such as heptonic anhydride, dodecenyl succinic anhydride, and polyazelain succinic anhydride; ethyleneamines, diethylaminopropylamine, dimethylaminopropylamine, N-aminoethylpiperazine,
Aliphatic amine-based curing agents such as trimethylhexamethylenediamine and modified aliphatic amines; and aromatic amine-based curing agents such as m-phenylenediamine, diaminodiphenylmethane, diaminodiphenylsulfone, metaxylylenediamine, and modified aromatic amines; , Others, isophoronediamine, dicyandiamide, piperidine, polyamide resin, phenolic resin, polythiol resin, mercaptan-based compound, boron trifluoride amine complex, imidazole-based compound, and the like. These may be used alone or in combination of two or more. You may use together.

Examples of the curing accelerator include tertiary amines, triphenylphosphine, stannath octoate, boron trifluoride complex, benzyldimethylamine,
DBU, 2,4,6-tris (dimethylaminomethyl)
Phenol, isocyanates, sulfonium salts,
Examples thereof include iodonium salts, diazonium salts, hydrazide compounds, nylon salt compounds, organometallic compounds, and the like. These may be used alone or in combination of two or more. When the addition amount of the curing accelerator is small, the curing of the thermosetting epoxy resin-based composition tends to be insufficient, and the mechanical strength of the obtained composite foamed molded article decreases. Since the curing of the product becomes too fast and the foamable particles hardly foam, and a composite foam molded article having a desired apparent density cannot be obtained, the epoxy resin 1
0.1 to 5 parts by weight is preferable with respect to 00 parts by weight.

The thermosetting epoxy resin composition may optionally contain a viscosity reducing agent or a thickening agent for adjusting fluidity, a thixotropic agent, and the like.
It is preferable that the thermosetting epoxy resin composition is appropriately adjusted and added so as to have a viscosity range described later. Examples of the viscosity reducing agent include solvents such as pentane, ethyl acetate, and methyl ethyl ketone. Examples of the thickener include rubbers such as acrylic rubber, epichlorohydrin rubber, isoprene rubber, and butyl rubber. Examples of the thixotropic agent include colloidal silica and polyvinylpyrrolidone.

Further, various plastics, rubbers and the like may be added to the thermosetting epoxy resin composition as needed in order to improve impact resistance. As the plastic, for example, polycarbonate,
Examples thereof include polyether sulfone, phenoxy resin, polyetherimide, polyvinyl formal, polyvinyl butyral, and polyethylene terephthalate. These may be used alone or in combination of two or more. Examples of the rubbers include butadiene-acrylonitrile rubber, styrene-butadiene rubber, and silicone rubber, and these may be used alone or in combination of two or more. The addition amount of these plastics and rubbers may be appropriately adjusted as necessary,
Usually, 5 to 30 parts by weight, preferably 8 parts by weight with respect to 0 parts by weight.
-20 parts by weight.

The solid component preferably contained in the hardened wall 3 is to secure the thickness of the hardened wall, and before and after the manufacturing process of the composite foam molded article 1, its particle size, single axis diameter, etc. There is no particular limitation as long as it does not substantially change, and it may be either solid or hollow.
The shape is not particularly limited, for example, particles,
Fibrous, rod-shaped, foil-shaped, rugby ball-shaped, anisotropic shapes such as spindles, and columnar bodies having a polygonal or elliptical cross section, among others, among which particulate, fibrous or rod-shaped preferable.

The above-mentioned solid component is added to the above-mentioned thermosetting epoxy resin-based composition before curing. If the amount of addition is small, the expandable particles may be expanded in the process of producing a composite foam molded article described later. In doing so, the thermosetting epoxy resin-based composition mixed with the expandable particles is easily extruded and easily flows to the bottom portion in the mold, and a composite foam molded article having uniform mechanical strength cannot be obtained, and Since the mechanical strength of the obtained composite foamed molded article decreases, the epoxy resin 10
The amount is preferably 60 parts by weight or less, more preferably 1 to 40 parts by weight, based on 0 parts by weight.

Examples of the particulate solid component include:
Calcium carbonate, talc, clay, clay, montmorillonite, mica, synthetic mica, smectite, graphite, layered silicate, magnesium oxide, zinc oxide, carbon black, silicon dioxide, titanium oxide, glass powder, hollow glass balloon, diatomaceous earth, kaolin And inorganic particles such as perlite, fluorite, bentonite, aluminum flake, nickel powder, gold powder, silver powder, and copper powder. These may be used alone or in combination of two or more. Above all, hollow glass balloons are preferred because they are lightweight and have excellent mechanical strength.

When the particle size of the particulate solid component is small, the thickness of the cured wall made of the epoxy resin-based cured product cannot be ensured, and when the particle size is large, the cured wall made of the epoxy resin-based cured product becomes unnecessarily thick. Alternatively, since the solid component protrudes from the hardened wall, 0.1 to 1000
μm is preferred, more preferably 0.1 to 100 μm, and even more preferably 0.1 to 50 μm. still,
When a solid component having a small particle size is used, the solid component aggregates to form secondary particles, and the thickness of the hardened wall is secured by the secondary particles. The particle size is a diameter calculated when the volume of the solid component is measured and the solid component is regarded as a true sphere from the obtained volume value.

As the fibrous solid component, for example,
Examples thereof include glass fiber, carbon fiber, alumina fiber, cellulose fiber, aramid fiber, polyamide fiber, polyester fiber, and metal fiber. These may be used alone or in combination of two or more. Gold fibers,
Silver fiber, copper fiber, aluminum fiber and the like can be mentioned. Examples of the rod-like solid component include those obtained by cutting the above-mentioned fibrous solid component into short pieces, and these may be used alone or in combination of two or more. When the uniaxial diameter of the fibrous or rod-shaped solid component is small, the thickness of the cured wall made of the epoxy resin-based cured product cannot be secured when it is small, and when it is large, the cured wall made of the epoxy resin-based cured product becomes unnecessarily thick. Alternatively, since the solid component protrudes from the hardened wall, the thickness is preferably 0.1 to 1000 μm, more preferably 0.1 to 100 μm, and still more preferably 0.1 to 50 μm. In addition, the said uniaxial diameter is
This is the minimum value of the diameter measured at the cut surface when a fibrous or rod-shaped solid component is cut in a uniaxial direction (a direction perpendicular to the long axis).

In addition to the above, it is preferable that the hardened wall 3 contains a fine solid component as a reinforcing material for increasing the strength of the hardened wall. Fine solid components include layered clay.

The composite foam molded article 1 of the present invention 1 has the above-described structure, but the mixing ratio of the polystyrene resin constituting the foam domain 2 and the epoxy resin constituting the cured wall 3 is as follows. When the amount of epoxy resin decreases, the mechanical strength decreases, the amount of polystyrene resin decreases, and when the amount of epoxy resin increases, the foam domain 2 portion decreases, the lightness decreases, and it is suitably used as a core material for sports equipment. Therefore, the polystyrene resin: epoxy resin (when the epoxy resin contains a solid component, excluding the solid component) has a weight ratio of 20:80 to 95: 5. Is preferred.

In the form of the composite foam molded article, a large number of foam domains are surface-bonded to each other without a gap through a cured wall made of a thin-film epoxy resin-based cured product. The matrix of the epoxy resin-based cured product may be scattered, the voids may partially exist in the cured wall, or the foam domains may partially communicate with each other.

When the apparent density of the composite foamed molded article is reduced, poor foaming is likely to occur in the manufacturing process, so that the mechanical strength tends to locally decrease, and the mechanical strength required for the core material of sports equipment and the like is required. Cannot be secured, and when it is large, the lightness is reduced, it cannot be suitably used as a core material of sports equipment and the like, and the handleability is also deteriorated. Therefore, it is limited to 0.1 to 0.5 g / cm ^3. . The apparent density is a value measured according to JIS A 9511.

The thickness of the composite foamed molded article may be appropriately determined according to the use or the like. For example, when the composite foamed molded article is used as a core material for sports equipment, the mechanical strength decreases when the thickness is reduced, and the weight decreases when the thickness is increased. 0.5 to 50 mm is preferable, since the handleability is deteriorated, the handleability is deteriorated, and the bulk is increased.

The present invention 2 relates to a method for stably producing the above-mentioned composite foam molded article in a simple step. Specifically, the present invention provides a method for producing the above-mentioned foamed particles made of a polystyrene resin and the above-mentioned thermosetting epoxy resin. The raw material composition is mixed with the base composition to form a mixed raw material composition, and the mixed raw material composition is heated in a molding die to a foaming temperature of the expandable particles to have an apparent density of 0.1 to 0.5.
The thermosetting epoxy resin-based composition is cured while foaming the foamable particles so as to obtain g / cm ³ .

The basic idea is that (a) the viscosity of the thermosetting epoxy resin-based composition at the time of contact with the expandable particles is set at the very upper limit of the flowable coating to lower the dissolution rate of the expandable particles. And (b) a heating means capable of quickly transferring the amount of heat in order to prolong the time during which the thermosetting epoxy resin-based composition capable of dissolving the expandable particles is in a molten state, c) The point is that the thermosetting epoxy resin composition in a fluidized state is mixed with foamable particles before foaming, rather than mixed with a foam, so that foaming and curing occur almost simultaneously.

The expandable particles are particles obtained by adding a foaming agent to a polystyrene resin similar to the polystyrene resin constituting the foam domain of the first aspect of the present invention. Examples of the method of adding a foaming agent to the polystyrene resin include a method of adding and kneading the foaming agent to the polystyrene resin, a method of impregnating the polystyrene resin with the foaming agent, and the like. As the expandable particles, commercially available polystyrene resin expandable beads may be used,
Particles of a polystyrene-based resin prepared so as to independently contain a foaming agent may be used.

Examples of the foaming agent include hydrocarbons,
Water, inorganic gas, pyrolytic foaming agent and the like, among them,
Hydrocarbons or water are preferred. Examples of the hydrocarbon include butane, pentane, and chlorofluorocarbon. Examples of the inorganic gas include carbon dioxide and nitrogen.

Examples of the thermal decomposition type foaming agent include azo compounds such as azodicarbonamide, azobisisobutyronitrile, azocyclohexylnitrile, diazoaminobenzene and azodicarbonamide ester; and nitroso compounds such as dinitrosoventamethylenetetramine. Compound;
sulfonyl hydrazide compounds such as p-toluenesulfonyl hydrazide, benzenesulfonyl hydrazide, p, p'-oxybisbenzenesulfonyl hydrazide, diphenyl sulfone-3,3'-disulfonyl hydrazide;
Azide compounds such as 4,4′-diphenyldisulfonyl azide and p-toluene sulfo azide; p-toluene sulfosemicarbazide, trihydrazinotriazine, sodium hydrogen carbonate, ammonium carbonate, and ammonium nitrite; They may be used alone or in combination of two or more.

If the amount of the above foaming agent is small, the obtained composite foamed molded article does not have a desired apparent density, the lightness is reduced, and it can be suitably used as a core material for sports equipment. It becomes impossible, the handling becomes poor, and when it increases, foaming failure easily occurs in the manufacturing process, the mechanical strength of the obtained composite foam molded article tends to locally decrease, and is required for the core material of sports equipment and the like Since the mechanical strength cannot be secured, the above polystyrene resin 1
0.1 to 50 parts by weight is preferable with respect to 00 parts by weight.

Further, a foaming aid may be added to the polystyrene resin together with a foaming agent for the purpose of adjusting the foaming speed. Examples of foaming assistants for increasing the foaming rate include, for example, zinc stearate, metal soaps such as calcium stearate, inorganic salts such as zinc zinc nitrate, adipic acid,
Acids such as oxalic acid are exemplified. Examples of the foaming aid that delays the foaming rate include maleic acid, organic acids such as phthalic acid, maleic anhydride, organic acid anhydrides such as phthalic anhydride, dibutyltin maleate, and tin compounds such as tin chloride. Can be

When the amount of the foaming aid is small, the added effect is not obtained, and when the amount is large, the added effect tends to be saturated. Therefore, 0.1 to 2 parts by weight based on 100 parts by weight of the polystyrene resin. 0.0 parts by weight is preferred.

As the shape of the expandable particles, spherical ones are preferably used, and confetti-shaped, rugby ball-shaped, dalma-shaped, and pellet-shaped resin obtained by cutting a resin extruded in a round shape at small intervals. Or a shape that cannot be defined by a uniform radius such as a crushed cullet shape. In essence, the foaming material only needs to be in a large number of individual sets, and may be a cube, a rectangular parallelepiped, a strand shape, a crushed shape such as a flat disk, or a small piece of sheet. Here, for convenience, the expression “particles” is used to represent these shapes.

The size of the expandable particles is not particularly limited. However, the size of the expandable particles is preferably 0. 0 from the viewpoint of easy production of the expandable particles, surface area of the expandable particles, and difficulty in producing softening unevenness due to heat transfer delay. 3 mm to 5 mm is preferred. The size of the expandable particles is an average diameter when the expandable particles are substantially spherical. In the case of a flat object or a strand-shaped object, the size of the portion having the smallest width is used.

When a mechanism for generating heat from the inside of the expandable particles is used together, expandable particles having a diameter larger than 5 mm can be used. As a mechanism for generating heat from the inside of the expandable particles, for example, there is a case where a metal powder is mixed into the expandable particles and electromagnetic induction is used in a high-frequency electromagnetic field environment.

In order to obtain a composite foam molded article having a homogeneous structure, the sizes of the expandable particles need not be strictly uniform, but are preferably substantially uniform. In addition, it is sometimes possible to give the cell membrane a unique three-dimensional structure by intentionally giving a distribution to the size of the expandable particles. Therefore, a mixture of expandable particles of different sizes may be used. obtain.

The expandable particles may be completely unfoamed, or may be foamed ones which have a margin for foaming, or may be foamed ones to which foaming ability is newly imparted.
Since the apparent density of the obtained composite foam molded article is likely to be uniform, it is more preferable to completely impart a foaming ability to a foamed article or a foamed article that has a margin for foaming than a completely unfoamed article. .

The expansion ratio of the expandable particles is 2 in volume ratio.
It is desirable that the number be twice or more. When the expansion ratio is within the above range, the foam domains are securely bonded to each other via the hardened wall due to an increase in the pressure in the mold due to the volume expansion of the expandable particles.

The thermosetting epoxy resin composition mainly comprises an epoxy resin constituting the cured wall and a curing agent thereof, and if necessary, a curing accelerator or the like is added. The same is used. The thermosetting epoxy resin-based composition may be previously prepared and stored, or may be prepared immediately before mixing with the expandable particles.

When the viscosity of the thermosetting epoxy resin composition at a temperature lower by 20 ° C. than the foaming temperature of the foamable particles is reduced, the thermosetting epoxy resin composition is mixed at the time of mixing with the foamable particles. It becomes easy to dissolve the polystyrene resin constituting the expandable particles, the desired apparent density cannot be obtained, and when it is large, it becomes difficult to mix uniformly with the expandable particles, and the obtained composite foam molded article Since the mechanical strength tends to be non-uniform,
00 Pa · s is preferred. The viscosity referred to in the present invention is JIS
It is a value measured according to the method B of K6862.

The foaming temperature of the expandable particles is a temperature at which the expandable particles are heated by a heating means, which will be described later, and depends on the polystyrene resin, the foaming agent, the shape, and the like constituting the expandable particles. Does not start or it takes a long time until the end of foaming. If the foaming temperature is too high, the expandable particles melt and do not form a good foam domain.
It is preferably around 00 ° C.

The thermosetting epoxy resin composition includes:
It is preferable to add the same solid components as in the first invention.
When the amount of the solid component added is small, when the expandable particles are expanded, the thermosetting epoxy resin-based composition mixed with the expandable particles is easily extruded and easily flows to the bottom portion in the mold, and is uniform. A composite foamed molded article having a high mechanical strength cannot be obtained, and when it is increased, the mechanical strength of the obtained composite foamed molded article is reduced.
It is preferably 0 parts by weight or less, more preferably 1 to 40 parts by weight.

The expandable particles and the thermosetting epoxy resin composition may further include a reinforcing material, a coloring agent, an ultraviolet absorber, an antioxidant, a flame retardant, and a mold preventive agent, as long as the object of the present invention is not impaired. Agent, plasticizer, coupling agent, electric conductive filler, magnetic filler, thermal conductive filler,
A modifying agent such as an antistatic agent may be added as needed.

The reinforcing material includes, for example, layered clay. As the colorant, a general pigment or dye is used. As the pigment, for example, titanium oxide,
Examples include iron oxide, carbon black, cyanine pigments, and quinacdrine pigments. Examples of the dye include an azo dye, an anthraquinone dye, an indigoid dye, and a stilbene dye. Further, metal powder such as aluminum flake, nickel powder, gold powder, silver powder, copper powder, and titanium oxide may be used as the coloring agent.

Examples of the ultraviolet absorber include salicylic acid ultraviolet absorber, benzophenone ultraviolet absorber, benzotriazole ultraviolet absorber, cyanoacrylate ultraviolet absorber, hindered amine light stabilizer and the like. Examples of the antioxidant include a phenol-based antioxidant, an amine-based antioxidant, a sulfur-based antioxidant, and a phosphorus-based antioxidant.

Examples of the flame retardant include halogen-based flame retardants such as chlorinated paraffin, hexabromophenyl ether and decabromodiphenyl ether; phosphoric acid-containing flame retardants such as ammonium polyphosphate, trimethyl phosphate and triethyl phosphate; melamine derivatives ;
Inorganic flame retardants such as red phosphorus, tin oxide, antimony trioxide, zirconium hydroxide, magnesium hydroxide, barium metaborate and the like.

Examples of the antifungal agent include 10,1
0'-oxybisphenoxyarsine, N- (fluorodichloromethylthio) phthalimide, N-dimethyl-
N'-phenyl-N '-(fluorodichloromethylthio) -sulfamide, 2-methoxycarbonylaminobenzimidazole, 2-methoxycarbonylaminobenzimidazole, thiabenzol and the like.

Examples of the plasticizer include a phosphate ester plasticizer, a phthalate ester plasticizer, an aliphatic monobasic ester plasticizer, an aliphatic dibasic ester plasticizer, and a dihydric alcohol ester plasticizer. Plasticizers, oxyester plasticizers, and the like.

Examples of the above coupling agent include vinyltrichlorosilane, vinyltrimethoxysilane, γ
Glycidyloxypropyltrimethoxysilane, γ-
Silane coupling agents such as aminopropyltriethoxysilane and N-β (aminoethyl) -γ-aminopropylmethyldimethoxysilane; isopropyltriisostearoyl titanate, tetraisopropylbis (dioctylphosphite) titanate, isopropyltri (N
(Aminoethyl-aminoethyl) titanate and the like.

Examples of the electrically conductive filler include particles of a metal such as gold, silver, copper, nickel, palladium, platinum, cobalt, rhodium, iridium, iron, ruthenium, osmium, aluminum, zinc, tin, and lead. Alloys of these metals in the form of particles; metal oxides such as tin oxide in the form of particles; conductive carbon allotropes such as carbon in the form of particles; glass, carbon, mica, Examples thereof include particles obtained by coating conductive metal on the surface of particles such as plastic.

[0057] As the magnetic filler, for example, cobalt ferrite-based magnetic material, metal magnetic, CrO _2,
Examples thereof include powders of γ-Fe ₂ O ₃ , Fe ₄ N, Ba ferrite, and the like. Examples of the thermally conductive filler include powders of copper, aluminum, beryllia, aluminum nitride, boron nitride, alumina, magnesia, titania, diamond, lead, zircon, and the like.

Examples of the antistatic agent include poly (oxyethylene) alkylamine, poly (oxyethylene) alkylamide, poly (oxyethylene) alkyl ether, poly (oxyethylene) alkylphenyl ether, glycerin fatty acid ester, sorbitan Nonionic antistatic agents such as fatty acid esters; Anionic antistatic agents such as alkyl sulfonates, alkylbenzene sulfonates, alkyl sulfates and alkyl phosphates; Cationic based antistatic agents such as quaternary ammonium chloride, quaternary ammonium sulfate and quaternary ammonium nitrate Antistatic agents; amphoteric antistatic agents such as alkyl betaine type, alkyl imidazoline type and alkyl alanine type; polyvinylbenzyl type cation, polyacrylic acid type cation And the like of the conductive resin.

The mixture of the expandable particles and the thermosetting epoxy resin composition is lower than the foaming temperature of the expandable particles and the viscosity of the thermosetting epoxy resin composition is 0.1.
It is preferable to perform the treatment in a range of 1 to 100 Pa · s. The viscosity of the thermosetting epoxy resin composition at the time of mixing,
When smaller, the thermosetting epoxy resin-based composition becomes easier to dissolve the polystyrene-based resin constituting the expandable particles,
A desired apparent density cannot be obtained, and when the desired apparent density is increased, it becomes difficult to mix uniformly, and the mechanical strength of the obtained composite foam molded article tends to become uneven.

The shape and material of the mold used in the present invention 2 are not particularly limited as long as it can withstand the foaming temperature and the foaming pressure. For example, a metal mold used for normal press working is naturally used well, and an aluminum casting mold, a resin mold, an FRP mold, or the like may be used. There may be.

Since the thermosetting epoxy resin composition has a property of adhering to the mold wall after curing,
When the obtained composite foam molded article adheres to the mold wall at the time of mold release, it is preferable to perform a mold release treatment on the mold wall. As the release treatment, for example, Teflon (registered trademark)
A resin baking process, a dense plating process of chromium or the like is suitably applied. In addition, for simple treatment, a spray-curing release lubricant, a Teflon resin tape, a Teflon resin sheet, a silicone resin tape, a silicone resin sheet, or the like may be used. In the case where a plate, a sheet, a film, or the like is covered with a thermosetting epoxy resin composition in a molding die and molded, such a release treatment may not be necessary.

The mixed raw material composition obtained by mixing the above expandable particles and the thermosetting epoxy resin composition has an apparent density of the composite foam molded article obtained in the above mold within the range of the present invention. It is heated and foamed. Examples of the method of adjusting the apparent density include, for example, a method in which pressure is applied to a mold, a method of regulating a range in which foaming and expansion are performed, a method of adjusting the expansion ratio of expandable particles by an amount of a foaming agent, and the like. Since the regulation is easy and the shape of the obtained composite foam molded article can be made into a desired shape, it is preferable to apply pressure to the molding die and regulate the range of foam expansion.

The most effective means of heating is a method of inserting a heating rod into a mold or a method of blowing hot air directly into a mold. Other simple methods include a method of directly heating the mold wall and a method of heating the mold wall with a heat medium such as steam, hot water or oil. Further, if the mold is made of a material having good heat transfer or a mold having a thin wall, the mold may be simply placed in an oven and heated. When using a method in which heat transfer from the mold wall is important without using hot air as the heating means, heat transfer will occur if the mold release film applied to the mold wall, such as Teflon resin or silicone resin, becomes thicker. Therefore, it is preferable to keep it to 50 μm or less as much as possible.

After molding, the obtained composite foam molded article is cooled. As a cooling means, it is possible to stop heating after foaming or simply remove the heating means and allow it to cool, or to circulate cooling water in the mold wall. Alternatively, the cooling may be positively performed with a cooling oil or the like. In order to reduce the manufacturing cycle time, it is preferable to actively cool.

The present invention 3 relates to a method for stably obtaining a laminated molded article using the above-mentioned composite foam molded article as a core material in a simple process, wherein a hard plate-like substance is mixed with a mixed raw material composition in a molding die. This is the same as the above-mentioned present invention 2 except that it is arranged in the above. Specifically, foamable particles made of a polystyrene resin and a viscosity of 0.1 at a temperature 20 ° C. lower than the foaming temperature of the foamable particles.
A thermosetting epoxy resin composition in a state of 1 to 100 Pa · s is mixed with the thermosetting epoxy resin composition in a state of a viscosity of 0.1 to 100 Pa · s to form a mixed raw material composition, The mixed raw material composition and the hard plate-like body in a molding die, such that the mixed raw material composition is sandwiched between the hard plate-shaped bodies, or
After arranging the mixed raw material composition so as to surround the hard plate-like body, the mixture is heated to the expansion temperature of the expandable particles, and the expandable particles are heated to an apparent density of 0.1 to 0.5 g / cm ^3. The thermosetting epoxy resin composition is cured while foaming.

The above-mentioned hard plate may be appropriately selected according to the intended use. For example, when the obtained laminated molded article is used as sports equipment such as a ski, a snowboard, a surfboard, and a board for sled, usually, the FRP is used.
A reinforcing fiber material referred to as "reinforcement fiber material" is preferably used. The hard plate bodies used may all be the same, or a combination of different ones may be used.

The thickness of the hard plate-like body may be appropriately determined according to the application and the like.
When used as sporting goods such as skis, snowboards, surfboards, sledboards, etc., the mechanical strength decreases as the thickness decreases, the lightness decreases as the thickness increases, the handling becomes poor, and the bulk increases. 0.5mm-50
mm is preferred.

The mixed raw material composition and the hard plate-like body are appropriately placed in a molding die according to a desired structure of the obtained laminated molded body. For example, in the case of a laminated molded article having a configuration in which the front and back of a composite foam molded article are sandwiched by a hard plate-like body, the mixed raw material composition is disposed between the hard plate-like bodies, and the entire periphery of the composite foam molded article is a hard plate. In the case of a laminated molded article having a configuration surrounded by a shape, it may be arranged so as to surround the mixed raw material composition with a hard plate.

As a method of adjusting the apparent density of the composite foamed molded product of the obtained laminated molded product, for example, a method of applying pressure to a molding die to regulate a range where foaming and expansion is performed, and a method of controlling foaming properties by an amount of a foaming agent and the like. Examples include a method of adjusting the expansion ratio of the particles, but the regulation is easy, and the shape of the obtained laminated molded article can be made into a desired shape. Since the adhesive strength between the shaped body and the composite foam molded article becomes strong, it is preferable to apply pressure to the mold and regulate the range in which the foam expands.

As a method of manufacturing a laminated molded article other than the above-mentioned present invention 3, a method of adhering the hard plate-like body to both sides or around the composite foamed molded article with an adhesive or the like; A method of fixing the hard plate-like body on both sides or around using a jig or the like can be given.

[0071]

The present invention will be described below in detail with reference to examples. (Examples 1 to 3, Comparative Examples 1 and 2) 55% by weight of a highly viscous epoxy resin (trade name “Epicoat 834” manufactured by Yuka Shell Epoxy Co., Ltd.) at room temperature, and a solid epoxy resin (oil at room temperature) Shell Epoxy Co., Ltd., product name "Epicoat 10"
01 ") 45% by weight of an epoxy resin mixture
After melting in an oven at 00 ° C. for 30 to 60 minutes and confirming that the melt was almost uniform, the epoxy resin mixture was allowed to cool to about 60 ° C.

Next, 100 parts by weight of the above epoxy resin mixture and an acid anhydride-based curing agent separately adjusted to 60 ° C. (trade name “ADEKA HARDNER EH-70” manufactured by Asahi Denka Co., Ltd.)
3 ") 50 parts by weight are stirred until homogeneous, then
3 parts by weight of a tertiary amine curing accelerator ("ADEKA HARDNER EHC-30" manufactured by Asahi Denka Co., Ltd.) was added, and the mixture was further stirred until the mixture became uniform to obtain a thermosetting epoxy resin composition.

The viscosities of “Epicoat 834” and “Epicoat 1001”, an epoxy resin mixture obtained by mixing them, and a thermosetting epoxy resin composition (JIS K 6
86B) was as shown in Table 1.

[0074]

[Table 1]

Further, the obtained thermosetting epoxy resin-based composition, expandable particles made of a polystyrene-based resin immediately preheated to 60 ° C. (trade name “Eslenbead HA”, manufactured by Sekisui Chemical Co., Ltd.), and Immediately before, a hollow glass balloon (trade name “Q-Cell”, manufactured by Pacific Chemical Co., Ltd.) preheated to 60 ° C. was mixed well with a predetermined amount shown in Table 2 to obtain a mixed raw material composition.

Separately, separately, 500 mm long × 70 mm wide ×
A plate-like body made of a reinforcing fiber material having a thickness of 5 mm (hereinafter referred to as "F
RP "). As shown in FIG. 2, the mixed raw material composition and the FRP were mixed to a length of 500 mm and a width of 7 mm.
In a closed mold 5 of 0 mm × 30 mm depth (consisting of a lower mold 51 and an upper mold 52 of the same shape), FRPs 61 and 62 are respectively placed on the lower mold 51 and the upper mold 52, and the FRP and the mold are used. Were arranged in such a manner that the length and width thereof coincided with each other, and a predetermined amount of the mixed raw material composition 7 shown in Table 2 was supplied so as to be interposed therebetween, and heated at 110 ° C. for 15 minutes. Thereafter, the mold was put into water and cooled to room temperature, and the mold was opened to obtain a laminated molded body. The apparent density of the composite foam molded part of the obtained laminated molded article was as shown in Table 2.

The flexural modulus of the obtained laminate was measured in accordance with JIS K7221. The results are shown in Table 2.

Further, the composite foam molded part of the obtained laminated molded body is cut at a substantially central portion in the thickness direction by inserting a cutter blade in parallel with the plate surface of the FRP, and the cut surface is visually observed throughout. did. As a result, in each of the composite foam molded articles, a foam domain in which a large number of fine foam particles having an average cell diameter of about 50 μm gathered (the average diameter was about 2.
8 mm) had a large number of cut surfaces via the hardened wall. Among them, the number of foam domains having a diameter of 1 mm or more (defective foaming) was counted, and the results are shown in Table 2.

[0079]

[Table 2]

[0080]

In the composite foamed molded article according to the first aspect of the present invention, a large number of foam domains formed of a polystyrene resin are gathered via a thin-film cured wall formed of a tough epoxy resin-based cured product. In addition, since the apparent density is within a predetermined range, it is lightweight and has excellent mechanical strength. In addition, the resin constituting the foam domain is a polystyrene-based resin that can be obtained relatively inexpensively, and the amount of the epoxy resin used is accordingly reduced, so that the cost is relatively low and the cost is low. Accordingly, the composite foamed molded article is suitably used for applications requiring compatibility between light weight and mechanical strength, such as sports use, construction, civil engineering use, ship material use, and housing equipment use. . In particular, as in the composite foam molded article according to claim 5,
It is suitably used as a core material for sports equipment such as a ski plate, a snowboard, a surfboard, and a sled plate, which is used in a state where the core material is sandwiched or surrounded by a hard plate. In the composite foam molded article according to the second aspect of the present invention, since the solid wall of the specific size is contained in the cured wall of the composite foam molded article, the required thickness of the cured wall made of a tough epoxy resin is required. , And excellent mechanical strength can be secured uniformly over the entire composite foam molded article.
In the production method according to the third aspect of the present invention, the thermosetting epoxy resin-based composition is mixed with the polystyrene-based resin expandable particles in a specific range of viscosity, so that the epoxy resin does not attack the polystyrene-based resin, The polystyrene resin and the epoxy resin, which were difficult to mix conventionally, can be uniformly mixed in a good state, and the composite foam molded article according to claim 1 can be stably obtained. Also, the process is simple, and the adjustment and management of the process are easy. In the production method according to the fourth aspect of the present invention, in the production method, since a solid component having a specific size is added to the thermosetting epoxy resin composition, when the expandable particles are expanded, the thermosetting is performed. The epoxy resin-based composition is prevented from flowing out to the bottom surface in the mold, and the required thickness of the cured wall made of the epoxy resin-based cured product can be easily secured in the obtained composite foam molded article. Therefore, the composite foam molded article according to claim 2 can be easily obtained. In the manufacturing method according to the sixth aspect of the present invention, since the hard plate and the composite foam molded body are integrally formed, the pressure and heat when the expandable particles expand are used to form the hard plate and the composite foam. The adhesive strength with the composite foamed molded article becomes strong, and when an external force such as bending is applied to the obtained laminated molded article, it is difficult for the two to peel off at the interface, and the mechanical strength of the laminated molded article does not decrease . Therefore, the obtained laminated molded product is suitably used as sports equipment such as skis, snowboards, surfboards, and sleds to which external force such as bending is likely to be applied. Also, the process is simple, and the adjustment and management of the process are easy.

[0081]

[Brief description of the drawings]

FIG. 1 is a schematic cross-sectional view showing one embodiment of a composite foam molded article of the present invention 1.

FIG. 2 is a schematic cross-sectional view showing a manufacturing process of the laminated molded body in the example.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 composite foam molded article 2 foam domain 21 air bubble 3 hardened wall 4 cell structural unit 5 closed mold 51 upper mold 52 lower mold 61, 62 FRP 7 mixed raw material composition

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) B29K 63:00 B29L 31:52 B29L 31:52 C08L 25:04 C08L 25:04 B29C 67/22 F-term ( Reference) 4F074 AA32 AA64 AE01 AE04 AE05 AE06 CA49 CC04Y CC06Y CC22Y CC32Y CC62 CE02 CE04 DA02 DA36 4F212 AA13 AA39 UA01 UB01 UB22 UC06 4J002 CD001 CD011 CD021 CD051 CD061 CD121 DE131 DA161 CL191 DD106 DA016 DA DE146 DE236 DJ006 DJ016 DJ036 DJ046 DJ056 DL006 FA016 FA042 FA046 FA076 FA086 FA106 FD140 FD150 FD330 GC00

Claims (6)

[Claims] 1. A large number of cell structural units comprising a foam domain made of a polystyrene resin and a thin-walled cured wall made of an epoxy resin-based cured material surrounding the foam domain are gathered without gaps, and A composite foam molded article having an apparent density of 0.1 to 0.5 g / cm ³ . 2. A hardened wall made of an epoxy resin-based hardened material, a solid component having a particle size of 0.1 to 1000 μm,
The composite foam molded article according to claim 1, further comprising a fibrous or rod-shaped solid component having a uniaxial diameter of 0.1 to 1000 μm. 3. A foamable particle made of a polystyrene resin, and a thermosetting epoxy resin composition having a viscosity of 0.1 to 100 Pa · s at a temperature 20 ° C. lower than the foaming temperature of the foamable particle. Are mixed in a state where the viscosity of the thermosetting epoxy resin composition is 0.1 to 100 Pa · s to obtain a mixed raw material composition, and the mixed raw material composition is heated to a foaming temperature of expandable particles in a molding die. Heating, apparent density 0.1 ~
While foaming the expandable particles to be 0.5 g / cm ^3, characterized in that curing the thermosetting epoxy resin composition, method of producing a composite foamed molded article according to claim 1. 4. A solid component having a particle size of 0.1 to 1000 μm in the thermosetting epoxy resin composition, or
The method for producing a composite foam molded article according to claim 3, wherein a fibrous or rod-shaped solid component having a uniaxial diameter of 0.1 to 1000 µm is added. 5. The composite foam molded article according to claim 1, wherein the composite foam molded article is used as a core material of sports equipment in which a core material is sandwiched or surrounded by a hard plate. 6. An expandable particle comprising a polystyrene resin, and a thermosetting epoxy resin composition having a viscosity of 0.1 to 100 Pa · s at a temperature 20 ° C. lower than the expansion temperature of the expandable particle. Are mixed in a state where the viscosity of the thermosetting epoxy resin-based composition is 0.1 to 100 Pa · s to form a mixed raw material composition, and the mixed raw material composition and the hard plate-like body are placed in a mold. As sandwiching the mixed raw material composition in the hard plate,
Alternatively, after the mixed raw material composition is arranged so as to surround the hard plate-like body, the mixed raw material composition is heated to a foaming temperature of the foamable particles, and foamed so that the apparent density becomes 0.1 to 0.5 g / cm ³ . A method for producing a laminated molded article, comprising curing a thermosetting epoxy resin composition while foaming particles.