JPS5821579B2 - Fukugousekisoutaino Seikeihouhou - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for molding a lightweight, high-strength thermosetting resin composite laminate.

In recent years, fiber-reinforced plastics (hereinafter abbreviated as FRP), which are obtained by impregnating fiber materials with thermosetting resin liquids such as unsaturated polyester resins and epoxy resins and curing them, have become easy to mold and lightweight. Because of its high strength, it is used for various purposes as a structural material.

However, such FRP also has problems in that it is inferior in rigidity and high in cost when compared to metal materials such as aluminum and steel.

It is well known to use FRP and other materials to form a sandwich structure for the purpose of improving the rigidity of FRP.

For example, there are methods in which a resin foam such as polyvinyl chloride foam or polylanthanum foam or a structure such as paper honeycomb is bonded to FRP as a core material, a method in which FRP is laminated and molded on a pre-formed solid foam core material, or A well-known method is to inject a foamable resin serving as a core material into the gap between a pre-formed FRP molded body.

However, such sandwich structures still have many problems such as limitations in product design, product uniformity, and productivity.

Furthermore, in order to improve the mechanical and electrical properties of FRP molded bodies, it is well known that fillers such as calcium carbonate, silica, and clay are mixed with resin and then molded.

The filler used here is usually a fine powder of 10 microns or less, which is mixed uniformly with the resin and impregnated into the fiber reinforcing material layer as one with the resin, and the filler layer containing the resin is impregnated into the fiber reinforcement layer. No separation occurs.

That is, the obtained FRP molded body is composed of a single layer having a relatively high specific gravity.

The present invention is intended to improve the rigidity, reduce the weight, and improve the productivity of FRP laminates, and relates to a very unique method for forming composite laminates as described below.

That is, a liquid thermosetting resin composition obtained by blending 10 to 60 volumes of micro hollow spheres with an average particle size of 30 to 500 microns is applied to a fiber reinforcement material, and the resin component of the resin composition is used for fiber reinforcement. A syntactic foam layer containing micro hollow spheres as a filler and a micro hollow sphere filling containing fibers as a reinforcing material, which is characterized by infiltrating the material and curing under pressure while the resin composition remains on the surface of the fiber reinforcing material. The present invention relates to a method of forming a composite layered body in which FRP layers containing no material are alternately laminated.

To further explain the method for molding the composite laminate of the present invention, a large piece of glass fiber reinforcing material, for example, 1141 m long cut into a predetermined size, is placed in a mold, and a micro hollow sphere filler is placed on top of it. The blended liquid resin composition is applied, and the resin component in the resin composition is permeated into the fiber reinforcing material, and the glass fiber reinforcing material is further placed on top of the resin composition remaining on the surface of the fiber reinforcing material. After placing the normal FR
The resin is cured and molded using a P molding method, for example, by pressing.

As shown in FIG. 1, the obtained molded body is a composite body having a sandwich structure in cross section consisting of a syntactic foam layer and a glass fiber-reinforced resin layer that does not contain a microscopic hollow sphere filler.

If necessary, a multilayer sandwich structure with high strength can be obtained by alternately stacking and molding syntactic foam layers and glass fiber reinforced resin layers that do not contain micro hollow sphere fillers.

Furthermore, it is possible to arbitrarily select whether the surface layer of the composite laminate is a syntactic foam layer or an FRP layer that does not contain a micro hollow sphere filler.

FIG. 2 illustrates a cross section of a multilayer composite laminate.

The resin used in the present invention may be any liquid thermosetting resin that can be cured by adding a curing agent or /' and heating, and examples thereof include unsaturated polyester resins and epoxy resins.

Of course, it is also possible to add commonly used pigments, dyes, etc. to these resins.

The proportion of hollow spheres of 30 to 500 microns in the liquid thermosetting resin is within a volume ratio of 10 to 60.

If the blending ratio is less than 10 parts, no sufficient effect will be observed, and if it is more than 60 parts, most of the resin will be consumed only for solidifying the syntactic foam layer, and the amount of resin impregnated into the fiber reinforcement layer will be small. This may cause defective resin impregnation in the fiber reinforcing layer, which may lead to deterioration in the performance of the laminate, and the increased viscosity of the resin composition makes molding work difficult.

The micro hollow sphere filler used in the present invention can be made of inorganic material, as long as it does not dissolve in the matrix resin used.
It doesn't matter whether it's organic or not.

Specifically, glass micro hollow spheres (for example, glass micro balloon IG manufactured by Emerson & Cumming Co., Ltd., USA) are used.
IOI), natural inorganic micro hollow spheres (e.g. Okazaki Kogyo (
(Shirasu Balloon from U.S. Co., Ltd.), carbon micro hollow spheres (e.g. Carbo Sphere from General Technology Co., Ltd.), synthetic resin micro hollow balls (e.g. Fëanol Micro Balloon from Union Carbide Co., U.S.), and others. be able to.

These micro hollow spheres have an average true specific gravity of 0.01 to 0.
．． 80 with an average particle size of 30 to 500 microns.

If this particle size is too small, it will penetrate into the fiber reinforcement material in the same way as fillers such as calcium carbonate, and the two-layer separation of the FRP layer that does not contain the micro hollow sphere filler and the syntactic foam layer will be incomplete, and Since the micro hollow spheres themselves have a high density, they are also disadvantageous in terms of weight reduction.

On the other hand, if the sphere diameter is too large, the strength of the micro hollow spheres themselves will be extremely reduced, and many will be broken during mixing with resin or during molding, resulting in a decrease in the strength of the syntactic foam layer and an increase in specific gravity. This is not desirable as it may cause

That is, in order to obtain a lightweight and strong composite consisting of an FRP layer and a syntactic foam layer that do not contain a micro hollow sphere filler, which is the object of the present invention, the average particle diameter of the micro hollow sphere filler must be 30. Most preferably in the range of ~500 microns.

The fiber reinforcing material used in the present invention is, for example, glass fiber, carbon fiber, etc., and is not particularly limited.

The shape can be selected depending on the purpose, such as mat, cloth, or roving.

Of course, it is clear from the gist of the present invention that the reinforcing material may be a mixture of glass fibers and other fibers such as carbon fibers.

The method for forming a composite laminate according to the present invention involves applying a resin composition containing a micro hollow sphere filler to a fiber reinforcement material ((()) to allow the resin component in the resin composition to permeate into the fiber reinforcement material and to form a resin composition. After the material remains on the surface of the fiber reinforcing material, hot press molding, cold bush molding, pressure back molding, hand molding, or continuous impregnation can be selected depending on the shape of the molded product and production volume.

The resulting molded product is a lightweight and high-strength composite laminate, but at the same time, because it contains air bubbles, it has excellent soundproofing properties.
It has sound insulation properties.

Therefore, it can be widely used in structural materials for ships, furniture, construction panels, structural materials for containers, and others.

The present invention will be explained below using Examples.

Example 1 100 parts by weight of an unsaturated polyester resin (Gothic 2063 manufactured by Showa Kobunshi Co., Ltd.) was mixed with micro hollow spheres (Shirasu Balloon, average particle size 150 microns, average particle density 0.34/
crn2) A resin composition A containing 20 parts by weight and 1 part of benzoyl peroxide as a curing catalyst is prepared.

The amount of micro hollow spheres in the resin composition A is approximately 4 by volume.
I am in charge of 0.

A glass mat (ICIn
One ply of chopped strand mat (having a weight of approximately 450 g per layer) is placed, and 230 g of resin composition A is placed on top of it.
Pour it on top.

Furthermore, 1 ply of glass mat was placed on top of it, the upper and lower O-types were closed, and pressure was applied at 9/crn2 for 4 minutes.

The obtained composite molded body has a cross section of F that does not contain micro hollow spheres.
It is a sandwich structure consisting of RP layer (0,6 turns thick) - syntactic foam layer (1, si cape 1) - FRP layer (0,6 m-thick) without micro hollow spheres.

Table 1 shows the results of physical property tests conducted using test pieces cut from the composite molded bodies.

Example 2 A glass mat l ply, a glass roving cloth (weight 60 og per 1 m2) i ply, and a glass mat 1 ply were placed on the lower mold (male mold) of the same molding mold as in Example 1,
On top of that, the resin composition A300 of Example 1. ! Apply 9.

Further, 1 ply of glass mat, 1 ply of glass roving cloth, and 1 ply of glass mat were placed thereon, and pressurized at a molding pressure of 40 kg/cm 2 for 7 minutes to obtain a sandwich FRP composite with a thickness of 8 mm.

The cross section of this composite is an FRP layer (1
, 5mm thick) - syntactic foam layer (5mml
Thickness) - Consists of an FRP layer (1°5 mm thick) that does not contain micro hollow spheres.

The results of measuring the physical properties of the composite molded product are shown in Table 1.

Example 3 Unsaturated polyester resin (Rivolac 15813Q'l
') 100 parts by weight, micro hollow spheres (shirasu balloons, average particle size 250 microns, average particle density 0.3097 cm2)
) Prepare a resin composition B containing 20 parts by weight and 15 parts of methyl ethyl lactone peroxide O as a curing catalyst.

The amount of micro hollow spheres in the tree composition B is approximately 4 by volume.
This is Section 5.

A male mold of a resin mold for cold bath V molding of a box-shaped container with a length of 44crn1, a width of 36a1, and a depth of 16cIn has a weight of 150.
g of preformed glass fiber reinforcement (glass chops preformed with a resin binder cut from glass roving) is placed, and resin composition B is poured onto it at 1300 g.
9 Apply.

Further, a glass fiber reinforcing material was placed on top of the mold, the upper and lower molds were closed, and pressure was applied at 3 to 9 cm'' for about 40 minutes.

The cross section of the obtained composite molded body is FR which does not contain micro hollow spheres.
P layer (0.7 mm thickness) - syntactic foam layer (
2.6 thick FRP layer (0.7 m) that does not contain minute hollow spheres
m thickness).

The physical properties of this composite molded article were measured as shown in Table 1.

Example 4 One part of epoxy resin (Epicote 828) was added to 90 parts by weight of methylimic anhydride as a curing agent, 1 part by weight of benzylmethylamine as a curing accelerator, and micro hollow spheres (glass microballoon IG 101, average particle size 7).
A resin composition C containing 22 parts by weight of 0 micron and average particle density of 0.33 is prepared.

The amount of micro hollow spheres in the resin composition C is approximately 3 by volume.
Becomes 0 person.

Using resin composition C and 4 plies of glass mat, length 6
0cfn.

A flat plate having a width of 30 cIr1 and a thickness of 0.7 cIn was molded using the following procedure.

One ply of glass mat is placed on the lower mold, and then resin composition C is applied.

Further, one ply of glass mat is placed on top of the mat, and resin composition C is applied in the same manner.Sequentially, the same operation is repeated until a predetermined structure is obtained.

At the end of the coating operation, the glass fiber layer was completely impregnated with resin.

In order to obtain smoothness of the surface of the composite molded product, place the molding upper mold,
After heating in a curing furnace at 90°C for 2 hours, 120°C for 2 hours, and 180°C for 8 hours, the cured product was taken out.

This cured product has a cross section as shown in FIG. 2, and is a composite laminate with a multilayer sandwich structure consisting of repeated FRP layers and syntactic foam layers that do not contain micro hollow spheres.

[Brief explanation of drawings]

FIGS. 1 and 2 are diagrams illustrating a cross section of a composite laminate obtained by the method of the present invention. In the figure, 1 indicates an FRP layer that does not contain a micro hollow sphere filler, and 2 indicates a syntactic foam layer.

Claims (1)

[Claims] 1 Uncured liquid thermosetting resin with an average particle size of 30 to 50
A resin composition obtained by blending 10 to 60 volumes of a micro hollow sphere filler with a diameter of 0 micron is applied to the fiber reinforcement material, and the resin component in the resin composition is permeated into the fiber reinforcement material, and the resin composition is A method for forming a composite laminate in which syntactic foam layers and fiber-reinforced plastics layers without micro hollow sphere fillers are alternately laminated, characterized by curing under pressure while remaining on the surface of the fiber reinforcing material. .