JP4404618B2 - Manufacturing method of fiber reinforced foam composite panel - Google Patents

Description

The present invention relates to a method for manufacturing a composite panel, and more particularly to a method for manufacturing a composite panel using a fiber-reinforced foamed plastic.

  Conventionally, urethane foam is generally used as a core material as a panel structure such as a door or a partition panel that has been provided with heat insulation and sound insulation, and instead of this, a honeycomb material may be used. On the other hand, it was comprised using resin plates, such as a steel plate, wood, and FRP, as a surface material.

  However, in these conventional doors and panels, since the core material and the surface material are completely different members, that is, made of materials having different properties, the processing man-hours during recycling are enormous. It was hanging. For this reason, the manufacturing process is complicated, and it is necessary to consider the adhesiveness between them.

  In terms of properties, since the core material is urethane foam, there is a slight difficulty in strength against external forces, and the urethane foam deteriorates due to contact with moisture, so there is a problem in terms of durability. It was sometimes pointed out.

Be those present invention to solve the conventional technical problems described above, good recyclability, moreover enhanced by nature, the and the manufacture of composite panels with fiber-reinforced plastic foam having improved durability It is intended to provide a method .

The gist of the present invention is as follows: (A) a thermosetting resin as a matrix resin, (B) a specific amount of reinforcing fibers, and (C) a shell made of a specific amount of an acrylonitrile copolymer. thermal expandable microcapsules having a foamable preform heating the cured fiber-reinforced plastic foam obtained by prepared consisting, as the surface material of the panel, the surface material according to said (a) a thermosetting resin of the same kind as the resin It is a manufacturing method of the used fiber reinforced foam composite panel. The integration of the core material and the surface material, which is such a foamable preform, requires that the core material be integrated in a mold for foam molding.

In terms of recycling, the surface material is preferably (A) the thermosetting resin is an unsaturated polyester resin, and the reinforcing fiber of the component (B) is a glass fiber having a length of 3 to 100 mm, and its content Is preferably 10 to 70 parts by weight based on the entire foamable preform. Further, the ripening expansible microcapsule of the component (C) is a core-shell type containing a low-boiling liquid organic compound, and the content is 0.1 to 50 weights with respect to 100 parts by weight of the component (A). Good part. In addition, the density as a core material of a composite panel is 0.4-1.5 g / cm < ³ >.

  According to the present invention, a composite panel using a fiber-reinforced foamed plastic molded body made of a foamable preform, which is particularly recyclable by using the same matrix for the core material and the surface material, It was possible to provide a composite panel that was strong and excellent in durability.

  The applicant has already provided new technology for fiber reinforced foamed plastic. Such a new technology is a sheet-like or bulk-like foamable preform containing (A) a thermosetting resin as a matrix resin, (B) reinforcing fibers and (C) a heat-expandable microcapsule, As a certain (A) thermosetting resin, a liquid material containing a thermosetting resin was used, and a fiber-reinforced foamed plastic molded body obtained by heat-curing the liquid material was provided (patent pending).

  Such a proposed fiber-reinforced foamed plastic has light weight and high strength properties, and is relatively easy to manufacture. Therefore, in the present invention, the fiber reinforced foamed plastic is used as a core material for a panel and has a surface. As a material, a fiber reinforced plastic, a steel plate, a wood plate, and preferably a surface material is formed into a composite panel using the same kind of resin as the matrix resin.

In order to produce the foamable preform of the present invention, a foamable molding material is first prepared. That is, a liquid material containing a thermosetting resin is used as the matrix resin of the component (A), and a heat-expandable microcapsule having a shell made of an acrylonitrile copolymer is blended as the component (C). In addition, materials conventionally used for SMC, BMC and TMC, such as low shrinkage agents, inorganic fillers, polymerization initiators, curing agents, thickeners, and curing accelerators and other additives used as necessary By doing so, it can be prepared.

  Examples of the matrix resin of the component (A) include unsaturated polyester resins, vinyl ester resins, epoxy resins, phenol resins, etc. Among them, unsaturated polyester resins are preferably used.

In the present invention, as the heat-expandable microcapsule of component (C) blended in the foamable molding material, the core is a low-boiling liquid organic compound, and the core-shell type heating in which the core is encapsulated with a shell made of a thermoplastic resin Swellable microcapsules are preferred. The core low-boiling liquid organic compound preferably has a boiling point of 150 ° C. or lower at normal temperature and normal pressure, and examples thereof include hydrocarbon compounds such as isobutane, pentane, and hexane, ethers, and the like. Examples of the thermoplastic resin forming the shell requires that the A acrylic nitrile copolymer. As the method for producing the heat-expandable microcapsules, those produced by an in situ polymerization method are preferable.

  This heat-expandable microcapsule preferably has an average particle size before heat expansion in the range of 0.5 to 100 μm, more preferably in the range of 1 to 70 μm. Further, the outer diameter after the thermal expansion is preferably at least twice the outer diameter before the thermal expansion, and more preferably about 3 to 10 times. If the average particle size before expansion is less than 0.5 μm, it is difficult to obtain sufficient foaming, and if it exceeds 100 μm, it is difficult to uniformly disperse and a homogeneous fiber-reinforced foamed plastic molded product may not be obtained. The expansion start temperature is preferably 80 ° C. or higher, more preferably 100 to 230 ° C. from the viewpoint of workability.

In the present invention, the amount of heat-expandable microcapsules as the component (C), the relative (A) a matrix resin liquid material 100 parts by weight of component, 0.1 to 50 parts by weight, more preferably Is in the range of 0.5 to 20 parts by weight. If the blending amount is less than 0.5 parts by weight, it is difficult to obtain a desired low-density fiber-reinforced foamed plastic molded body, and if it exceeds 50 parts by weight, the strength of the plastic molded body may be insufficient.

  As a low shrinkage agent blended in the foamable molding material in the present invention, polystyrene, polyethylene, polyvinyl acetate, polymethyl methacrylate, saturated polyester, styrene-butadiene copolymer, styrene-methacrylic acid copolymer, polycaprolactone, Examples thereof include thermoplastic resins such as polybutadiene. The blending amount is selected in consideration of the shrinkage rate, surface smoothness, etc. of the obtained foamed plastic molding, but the weight ratio of the matrix resin to the low shrinkage agent is usually 90:10 to 50. : 50, preferably in the range of 80:20 to 60:40.

  Examples of the filler to be blended in the foamable molding material in the present invention include calcium carbonate, silica, talc, aluminum hydroxide, clay, mica, hollow balloon (glass, shirasu, cement), ferrite, zinc white and the like. Among them, among them, calcium carbonate is preferable. The blending amount is usually selected in the range of 50 to 200 parts by weight with respect to 100 parts by weight of the total amount of the matrix resin and the low shrinkage agent.

  When the foamable molding material in the present invention is an unsaturated polyester resin-based foamable molding material, an organic peroxide is usually used as a polymerization initiator or a curing agent, such as methyl ethyl ketone peroxide, acetylacetone peroxide, t-butylperoxy. Examples include benzoate, benzol peroxide, dicumyl peroxide, cumene hydroperoxide and the like. The blending amount of the polymerization initiator is usually selected in the range of 0.3 to 5 parts by weight, preferably 0.7 to 3 parts by weight with respect to 100 parts by weight of the matrix resin.

  In the case of an unsaturated polyester resin-based foamable molding material, examples of the thickener blended therein include magnesium oxide, magnesium hydroxide, potassium oxide, potassium hydroxide and the like. The blending amount of the thickener is usually selected in the range of 0.5 to 5 parts by weight, preferably 0.7 to 2 parts by weight with respect to 100 parts by weight of the matrix resin.

  In the unsaturated polyester resin-based foamable molding material in the present invention, the viscosity at a temperature of 25 ° C. 30 minutes after the addition of the thickener is preferably in the range of 50 to 300 Pa · S, and this viscosity is 300 Pa · It is because the impregnation property to the reinforcing fiber becomes insufficient when it exceeds S.

  In the unsaturated polyester resin-based foamable molding material in the present invention, other additives such as a curing accelerator, a polymerization inhibitor, a mold release agent, an antioxidant, an ultraviolet absorber, a colorant and the like may be blended as desired. it can. For example, examples of the curing accelerator include cobalt naphthenate, cobalt octoate, N, N-dimethylaniline, N, N-diethylaniline, and the like. Examples of the polymerization inhibitor include hydroquinone, P-benzoquinone, methylhydroquinone, trimethylhydroquinone, t-butylhydroquinone and the like.

  Next, the foamable preform of the present invention is obtained by impregnating the foamable molding material obtained as described above into the reinforcing fiber of the component (B), to form a sheet (SMC, TMC) or bulk (BMC) ).

  Examples of the reinforcing fiber include glass fiber, carbon fiber, and organic fiber such as polyester fiber, nylon fiber, and aramid fiber, among which glass fiber is preferable. As the glass fiber, a long fiber and / or a short fiber obtained by cutting a roving is used. The long fiber has a length of usually 15 to 100 mm, preferably 20 to 50 mm, and the short fiber has a length of usually 5 to 15 mm, preferably 6 to 13 mm.

  In the foamable preform of the present invention, the reinforcing fiber is usually contained in the range of 10 to 70% by weight, preferably 15 to 50% by weight, based on the whole preform.

The fiber-reinforced foamed plastic molded body of the present invention is obtained by setting the sheet-like (SMC, TMC) or bulk-like (BMC) foamable preform so obtained in the mold and heat-curing. Can be obtained. That is, if the foamable preform is set in the mold, the mold clamping is interrupted by the thickness of the molded product that is assumed after foaming, and molding is performed by a method that uses foaming pressure, molding is possible at low pressure. It has the advantage that the cost of the metal mold can be reduced. The density of the fiber-reinforced foamed plastic molding of the present invention is preferably 0.4 to 1.5 g / cm ³ , more preferably 0.5 to 1.2 g / cm ³ .

Next, an embodiment for producing the fiber-reinforced foamed plastic molded body of the present invention will be described taking the case of SMC as an example.
First, (A) component matrix resin, (C) component heat-expandable microcapsules, low shrinkage agent, filler, polymerization initiator and curing agent, and curing accelerators and other additives used as necessary. A compound paste is prepared by kneading. Subsequently, the foamable molding material obtained by mixing this with a thickener is immediately supplied to the SMC impregnation machine.

Next, a predetermined amount of the foamable molding material is applied to each of the two carrier films of the present invention, and then (B) glass fiber is chopped with a cutter as a reinforcing fiber on the coating layer of the lower film. the send down. Next, an upper film having a coating layer thereon is superposed so that the coating layer is on the inside, and rolls are pressed on the top and bottom of the superposed film to impregnate the composition into sandwiched glass fibers. Thus, the sheet-like foamable preform (SMC) of the present invention is obtained. The thickness of the thus obtained sheet-like foamable preform of the present invention is usually preferably 1 to 10 mm from the viewpoint of the permeability of the molding material to the glass fiber.

  Next, the sheet-like foamable preforms obtained as described above are usually set in a mold by using a plurality of sheets, and clamped according to the thickness after foaming at 130 ° C to 160 ° C. Or after shrinking the mold at 5 to 10 MPa, after about 1 minute, the mold is raised in accordance with the thickness after foaming. A fiber-reinforced foamed plastic molding is obtained.

The surface material is not particularly limited, and a steel plate, wood plate, plastic plate, etc. can be selected. However, in terms of recyclability, glass fiber reinforced plastic is preferable, and more specifically, the same as that adopted for the foamed plastic molded body. Needless to say, it is preferable to use a plastic plate. In the present invention, a plastic plate is used as a surface material , and when a foamed plastic molded body as a core material is formed, the plastic material of the surface material is injected into the same mold and molded integrally, thereby reinforcing the fiber. A foam composite panel is obtained.

"Plastic molded body 1"
(1) Preparation of foamable preform A matrix resin (unsaturated polyester resin, number average molecular weight: 3000) 100 parts by weight, a low shrinkage agent (35% styrene monomer solution of polystyrene), 25 parts by weight, a viscosity modifier (styrene monomer) ) 10 parts by weight, 1 part by weight of a curing agent (t-butylperoxybenzoate), 0.05 part by weight of a polymerization inhibitor (parabenzoquinone), a heat-expandable microcapsule (“Microsphere FlO5D” manufactured by Matsumoto Yushi Co., Ltd.) In addition, 5 parts by weight of an internal mold release agent (zinc stearate), 4 parts by weight of a modifier (powder polyethylene) and 140 parts by weight of a filler (heavy calcium carbonate) were kneaded to prepare a compound base. Subsequently, as a thickener paste, a mixture of 1 part by weight of a thickener (magnesium oxide) and 4 parts by weight of a resin (unsaturated polyester resin having an acid value of 0) was added to produce a foamable molding material. The unsaturated polyester resin (matrix resin) is subjected to an ester reaction using a combination of terephthalic acid and maleic acid as the dicarboxylic acid component, and a combination of propylene glycol and neoventyl glycol as the glycol component. It was obtained.

  Next, about 30 minutes after the addition of the thickener base, glass fiber having a length of about 25 mm obtained by chopping glass roving with a cutter was added at a ratio of 30% by weight with respect to the total amount of the foamable preform. Thus, a sheet-like foamable preform (SMC) was produced.

(2) Fabrication of fiber-reinforced foamed plastic molding The sheet-like foamable preform obtained in (1) above was cut into 100 × 100 mm, and this was 200 × 200 mm flat plate mold so that the total amount was 170 g. After being laminated and set inside, it was press-molded at a pressure of about 5 MPa through a 4 mm spacer to produce a fiber-reinforced foamed plastic molded body.
Table 1 shows the molding conditions and the physical properties of the obtained molded body.

"Plastic molded body 2"
In Example 1, a fiber-reinforced foamed plastic molded body was manufactured in the same manner as in Example 1 except that the spacer thickness was 6 mm when the fiber-reinforced foamed plastic molded body was manufactured.
Table 1 shows the molding conditions and the physical properties of the obtained molded body.

"Plastic molded body 3"
(1) Preparation of foam preform In Example 1 (1), dicumyl peroxide was used instead of t-butylperoxybenzoate as a curing agent, and the amount of parabenzoquinone as a polymerization inhibitor was 0.1 weight. A sheet-like foamable preform (SMC) was produced in the same manner as in Example 1 (1) except that the part was changed to the part.

(2) Fabrication of fiber-reinforced foamed plastic molding The sheet-like foamable preform obtained in (1) above was cut into 100 × 100 mm, and this was 200 × 200 mm flat plate mold so that the total amount was 170 g. After setting a plurality of layers inside, press molding was performed at a pressure of about 5 MPa through an 8 mm spacer to prepare a fiber-reinforced foamed plastic molded body.
Table 1 shows the molding conditions and the physical properties of the obtained molded body.

"Plastic molded body 4"
In Example 1, a fiber-reinforced foamed plastic molded body was prepared in the same manner as in Example 1 except that a spacer was not used and the mold was opened 8 mm after clamping for 45 seconds in the production of the fiber-reinforced foamed plastic molded body. Was made.
Table 1 shows the molding conditions and the physical properties of the obtained molded body.

  In Table 1, the density was measured according to JIS K7222.

"Manufacture of composite panels 2"
An FRP plate (thickness 4 mm) was used as the surface material and set on the surface of a mold for obtaining a plastic foam molded article, and foam molding was performed. Adhesion was sufficient and a satisfactory composite was obtained.

“Manufacture of composite panels 3”
As the surface material, an uncrosslinked sheet (SMC) in which a foaming agent for a plastic foam molded article was not blended was used. That is, a plastic foamable sheet (SMC) and this uncrosslinked sheet were laminated in a mold and foamed. The resulting composite was a foam at the center, and a composite in which a non-foamed FRP surface material of about 4 mm was laminated on the surface.

  In the case of recycling, if the whole is the same type as the matrix resin, there is an excellent feature that it is not necessary to remove both.

The composite panel using the fiber reinforced foamed plastic molding according to the present invention is a composite panel which is particularly excellent in recyclability, strength and durability by using the same matrix for the core material and the surface material. In addition, it can be widely used as various panel structures such as doors and partition panels provided with heat insulation and sound insulation.

Claims (9)

(A) Thermosetting resin as a matrix resin, (B) Reinforcing fiber comprising 10 to 70 parts by weight of glass foam having a length of 3 to 100 mm, and (C) (A ) A foamable preform formed from heat-expandable microcapsules containing 0.1 to 50 parts by weight per 100 parts by weight of the component and encapsulating a low boiling liquid organic compound in a shell made of an acrylonitrile copolymer was obtained. after a panel core material preparation step of obtaining a core material of the panels with fiber-reinforced plastic foam by heat-curing the foamable preform, at the same time the core material and the surface material of the panel in the mold method for producing a fiber reinforced foam composite panel characterized by having a integrated process for integrated with.   (A) Thermosetting resin as a matrix resin, (B) Reinforcing fiber comprising 10 to 70 parts by weight of glass foam having a length of 3 to 100 mm, and (C) (A Foam to obtain a foamable preform formed of heat-expandable microcapsules containing 0.1 to 50 parts by weight of 100 parts by weight of a component and encapsulating a low-boiling liquid organic compound in a shell made of an acrylonitrile copolymer Preform forming body, heat-curing the foamable preform and surface material in a mold, forming a panel core material using fiber-reinforced foamed plastic, and panel core material and surface material And an integration step of simultaneously performing integration with the fiber reinforced foam composite panel. The method for manufacturing a fiber-reinforced foam composite panel according to claim 1 or 2, wherein the surface material is a fiber-reinforced plastic plate . The method for producing a fiber-reinforced foam composite panel according to claim 1 or 2 , wherein the surface material is a surface material made of the thermosetting resin (A) . The method for producing a fiber-reinforced foam composite panel according to any one of claims 1 to 4, wherein the (A) thermosetting resin is an unsaturated polyester resin . The method for producing a fiber-reinforced foam composite panel according to any one of claims 1 to 5 , wherein the surface material is an unsaturated polyester resin .   The panel core preparation step prepares a compound paste containing (A) a thermosetting resin as the matrix resin and (C) a heat-expandable microcapsule, and further mixes a thickener to form foam. Obtaining a material;
  The foamable molding material thus obtained is applied onto two carrier films to form a foamable molding material coating layer, and at least one of the two carrier films on which the foamable molding material coating layer is formed is foamable. Placing the reinforcing fiber (B) on the molding material coating layer;
  A foamable molding material coating layer comprising (B) a foamable molding material coating layer including reinforcing fibers between two carrier films, wherein the foamable molding material coating layers on the two carrier films are overlapped and pressed against each other. Forming a preform, and
  Heating and pressurizing the obtained foamable preform, and foaming the (C) heat-expandable microcapsule contained in the foamable molding material coating layer to obtain a fiber-reinforced foamed plastic;
  The manufacturing method of the fiber reinforced foam composite panel of Claim 1 which has these in this order.     The panel core material preparation step prepares a compound paste containing (A) a thermosetting resin as the matrix resin, (B) reinforcing fibers, and (C) heat-expandable microcapsules, and further increases the viscosity. Mixing the agent to obtain a foamable molding material;
  Using the obtained foamable molding material, forming a foamable preform,
  Heating and pressurizing the obtained foamable preform, and foaming the (C) heat-expandable microcapsule contained in the foamable molding material coating layer to obtain a fiber-reinforced foamed plastic;
  The manufacturing method of the invention fiber reinforced foaming composite panel of Claim 1 which has these in this order.   The step of obtaining the fiber reinforced foamed plastic and the integration step are steps of heating and pressing after laminating the foamable preform and the surface material of the panel obtained by the step of obtaining the foamable molding material. The manufacturing method of the fiber reinforced foam composite panel of Claim 2.