JPH10166464A - Production of long fiber reinforced foamed molded object - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an inexpensive long fiber reinforced foamed molded object having a large amt. of a solid filler uniformly dispersed therein with good workability. SOLUTION: At first, a solid filler 11 is mixed with a liquid raw material 21 having lower viscosity to obtain a liquid mixed raw material which is, in turn, mixed with a liquid raw material 31 having high viscosity to obtain a foamed curable resin soln. 51. This resin soln. 51 is sprinkled over fiber bundles 8 composed of a long fiber reinforcing material and the fiber bundles 8 are crumpled to infiltrate the resin soln. 51 into the long fiber reinforcing material.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a long fiber reinforced foam molded article.

[0002]

2. Description of the Related Art A long-fiber-reinforced foamed article which is similar in appearance to natural wood and has physical properties equal to or higher than that of natural wood is used as a structure for building materials. The long fiber reinforced foamed molded article is made of a fiber bundle of glass fiber, which is expensive as a raw material, and a synthetic resin such as a polyurethane resin and an unsaturated polyester resin, and therefore, is extremely expensive as compared with natural wood.

Therefore, a method of manufacturing a long-fiber-reinforced foam molded article capable of solving the above-described problems has been proposed by the present applicant in, for example, Japanese Patent Application Laid-Open No. 54-37172. I have. In this method, a foaming curable resin liquid is sprinkled on a fiber bundle of a long fiber reinforcing material aligned in one direction, and a solid filler is sprinkled on the fiber bundle from another supply port. While dispersing the solid filler in the foam-setting resin liquid. Then, after impregnating the foam-curable resin liquid between the long fiber reinforcement and the long fiber reinforcement constituting the fiber bundle, the liquid is passed through a molding passage,
In this passage, foaming and curing are performed to form a cross-sectional shape of the molding passage.

In other words, according to this method, an inexpensive solid filler is sprinkled to disperse the solid filler in the molded article, so that the properties of the molded article itself are not impaired, and the long fiber reinforcing material or the synthetic resin can be used. The amount of use can be reduced, and a molded article that is less expensive than a conventional molded article can be provided.

[0005] However, in the above method, although the cost can be reduced as compared with the conventional molded body, as described above, the foam curable resin liquid and the solid filler are separately sprinkled on the fiber bundle of the long fiber reinforcement, Kneading with a rubbing plate, while dispersing the solid filler in the foam-curable resin liquid, while impregnating the foam-curable resin liquid between the long fiber reinforcement and the long fiber reinforcement of the fiber bundle, When the added amount of the solid filler is increased, the solid filler is not dispersed well, which may result in a defective product due to lack of uniform impregnation. Therefore, the addition amount of the solid filler must be stopped to about 1 to 2% of the whole.

In addition, since the solid filler is sprinkled, the solid filler may be scattered as dust and deteriorate the working environment.

[0007]

SUMMARY OF THE INVENTION In view of such circumstances, the present invention provides a long-reinforcing foam molded article in which a solid filler is dispersed in a large amount and uniformly, and which can provide an inexpensive long-fiber reinforced foam molded article with good workability. An object of the present invention is to provide a method for producing a fiber-reinforced foam molded article.

[0008]

In order to achieve such an object, a method for producing a long-fiber-reinforced foam molded article according to the present invention comprises a plurality of long-fiber reinforcements formed in one direction. The fiber bundle is continuously advanced in one direction, and at least a liquid material containing the compound (A) and another liquid material containing the compound (B) reacting with the compound (A) are mixed at least. A foam-curable resin liquid is supplied in the course of the fiber bundle, and a long-fiber reinforcing material constituting the fiber bundle by foaming the curable fiber bundle supplied with the foam-curable resin liquid. A step of impregnating with a long fiber reinforcing material, and further proceeding the fiber bundle impregnated with the foaming-curable resin liquid to a molding passage, and foaming and curing the foaming-curable resin liquid in the passage. Forming into a shape The method of manufacturing a 維補 strong foam moldings, of the two liquid source material, and to keep previously mixed solid filler in the liquid raw material towards low viscosity.

In the above structure, the foam-setting resin liquid means a liquid resin which foams and hardens in a relatively short time, and for example, polyurethane resin, phenol resin, polyester resin and the like are preferably used. By the way, liquid materials are generally divided into a main agent that is relatively stable in an external environment (temperature, humidity, ultraviolet rays, etc.) and a hardening agent or an additive that is relatively unstable. Viscosity is typically higher than other curing agents and additives.

That is, the strength and physical properties of the obtained molded article are greatly affected by the chemical structure of the base material. For example, as the chemical structure of the base material contains more rigid functional groups such as a benzene ring, and the like, and the curing agent and the like. As the number of functional groups (reacting hands) reacting increases and the structure becomes more complex, the molecular movement is inhibited and the viscosity of the raw material increases, but the chemical structure of the final molded product is more likely to take a three-dimensional network structure. The strength is excellent.

Therefore, in order to obtain a resin molded product which requires strength such as a structural material or a general FRP, it is necessary to use a material having a somewhat high viscosity of the base material.

When a polyurethane resin is used as the foam-setting resin liquid, one liquid raw material contains an isocyanate compound as the compound (A), and the other liquid raw material reacts with the isocyanate compound. And a polyol compound as the compound (B). Since the viscosity of the liquid material on the side containing the isocyanate compound is usually lower, the fixed filler is added to the liquid material on the side containing the isocyanate compound.

The viscosity of the polyol compound is preferably about 500 to 5000 cps / 25 ° C. In other words, the use of a material having a temperature of 500 cps / 25 ° C or less generally lowers the mechanical strength and surface hardness of the molded product, and if it exceeds 5000 cps / 25 ° C, the temperature dependence of viscosity is large and handling such as temperature control is difficult, There is also a limit to the amount of filler mixed due to the pressure of the piping in the equipment and the necessary power of the pump.

On the other hand, the viscosity of the isocyanate compound is preferably about 100 to 1000 cps / 25 ° C. In other words, when a material having a temperature of 100 cps / 25 ° C. or less is used, the mechanical strength of the molded product and the dimensional stability when the mold is released from the mold generally decrease.
If it exceeds 00 cps / 25 ° C., it becomes extremely difficult to impregnate and complex with a reinforcing agent such as glass fiber after mixing with the polyol.
In particular, in a system in which a solid filler is mixed, impregnation and complexation become more difficult.

Further, there are many types of polyol compounds and isocyanate compounds, and if the above conditions are satisfied, they can be properly used depending on the target level and application of the finally obtained molded article. As the polyol compound, a polyether-based polyol is preferable, and as the isocyanate compound, diphenylmethane diisocyanate-containing material is preferable.

The term "solid filler" refers to a filler in the form of short fibers or powder, for example, inorganic short fibers such as glass fiber, asbestos fiber and mineral fiber, natural fibers such as cotton and hemp, rayon and the like. Recycled fibers, synthetic short fibers such as synthetic fibers such as polyamide, polyester and polyolefin, inorganic powders such as calcium carbonate, talc, clay, silica sand, shirasu balloon, pumice stone, and wood powder, bamboo powder,
Examples include organic powders such as starch and rice bran, or mixtures thereof, and cuttings of long fiber reinforced foamed molded products.

In addition, additives such as a catalyst, a colorant, and an ultraviolet absorber may be added to each liquid raw material, if necessary, for example. It may be added simultaneously with mixing.

[0018]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 schematically shows an example of a production apparatus used for carrying out the method for producing a long-fiber-reinforced foam molded article according to the present invention.

As shown in FIG. 1, this manufacturing apparatus A includes a solid filler supply device 1, a first tank 2, a second tank 3, a mixing extruder 4, a spraying device 5, an impregnating device 6, and a molding passage 7. It has. The solid filler supply device 1 includes a solid filler 11.
And a belt feeder 13 for transferring the fixed filler 11 of the hopper 12 to the hopper 41 of the mixing and extruding machine 4.

The first tank 2 stores the liquid raw material 21 having the lower viscosity, and can supply the stored liquid raw material 21 into the cylinder 42 of the extruder 4 via the pump 22. The second tank 3 stores the liquid material 31 having the higher viscosity, and can supply the stored liquid material 31 to the spraying device 5 via the pump 32.

The mixing extruder 4 combines the solid filler 11 supplied from the hopper 41 by the solid filler supply device 1 and the liquid raw material 21 supplied from the first tank 2 by a screw (not shown) in a cylinder 42. After mixing, the liquid mixed raw material is sprayed through a pump 43 into a spraying device 5.
Can be supplied. The spraying device 5 continuously mixes the liquid raw material 31 supplied from the second tank 3 and the liquid mixed raw material supplied from the mixing extruder 4 while continuously aligning a large number of long fiber reinforcing materials in one direction. The foamed curable resin liquid 51 is sprinkled and supplied onto the fiber bundle 8 that proceeds.

The impregnating device 6 includes rubbing plates 61, 61 and an impregnating plate 62. The rubbing plates 61, 61 are reciprocated in a direction orthogonal to the traveling direction of the fiber bundle 8, and are moved between the impregnating plates 62. The fiber bundle 8 is rubbed, and the foam-curable resin liquid 51 supplied on the fiber bundle 8 is uniformly impregnated between the long fiber reinforcing material constituting the fiber bundle 8 and the long fiber reinforcing material. The molding passage 7 heats the foam-setting resin liquid 51 to foam-harden it,
It is designed to be molded into a foamed molded body along the cross-sectional shape in the molding passage 7.

According to the manufacturing method of the present invention using the manufacturing apparatus as described above, the solid filler 11 is mixed in advance in the foaming curable resin liquid
Together with the fiber bundle 9,
There is no possibility that the solid filler becomes dust and scatters to deteriorate the working environment. Moreover, in this manufacturing method, after the solid filler 11 is first mixed with the low-viscosity liquid material as described above, the low-viscosity liquid material and the high-viscosity liquid material are mixed to form the foam-curable resin liquid 51. Since the solid filler 11 is first mixed with the high-viscosity liquid raw material, the amount of the solid filler 11 added can be further increased as compared with the method of mixing both liquid raw materials. The filler is dispersed in a large amount and uniformly, so that an inexpensive long-fiber-reinforced foam molded article can be obtained.

That is, if the solid filler is mixed first with the liquid material having a high viscosity, the viscosity is further increased, and it becomes difficult to mix the liquid material having a low viscosity. However, the solid filler is first added to the liquid material having a low viscosity. Since the mixed liquid raw material and the other liquid raw material having high viscosity are mixed, the difference in viscosity between the liquid mixed raw material and the other liquid raw material is small, and mixing can be easily performed.

Therefore, even if the resin has a short pot life and must be mixed in a short time, molding failure due to insufficient mixing of the main agent and the curing agent does not occur.

Of course, since the solid filler 11 is uniformly dispersed, the mechanical properties required for the structural material are not impaired.

[0027]

Embodiments of the present invention will be described below in detail.

(Example 1) 4,4'-Diphenylmethane diisocyanate (MD
I, viscosity: 180 cps / 25 ° C., specific gravity: about 1.23) 100 parts by weight of synthetic wood (FFU) manufactured by Sekisui Chemical Co., Ltd. (trade name: FFU) as a solid filler
μm, a true specific gravity of about 1.5) was added in different amounts, and the mixture was stirred using a rotary lab mixer to obtain liquid mixed raw materials having various mixing ratios.

Then, the mixing state of the chips at each mixing ratio and 4,4'-diphenylmethane diisocyanate was examined.
The results are shown in Table 1. Next, each of the liquid mixed raw materials and a polyol (viscosity of 35) as a liquid raw material having a high viscosity were used.
00 cps / 25 ° C., specific gravity about 1.1), water 2%, tin-based organic substance as catalyst 0.15%, silicone oil 1%
And the mixture containing 4,4′-diphenylmethane diisocyanate of 100 parts by weight with respect to 100 parts by weight of the liquid mixed raw material, and a polyol in a ratio of 150 parts by weight, and uniformly stirred at 3000 rpm for 30 seconds, respectively.
After the foam-curable resin liquid was obtained, the appearance of the urethane foam obtained by foam-curing the foam-curable resin liquid was examined. The results are shown in Table 1.

In Table 1, the evaluation of the mixed state of the liquid mixed raw materials was as follows: ◎: extremely good, ○: good, Δ: slightly non-uniform,
× represents non-uniformity, the appearance of urethane foam is ◎: foam and bubbles are not uneven, ○: foam and bubbles are slightly uneven, △: summer orange-like irregularities on the surface, ×: clear Each represents an unmixed part.

[0031]

[Table 1]

(Comparative Example 1) Instead of 4,4'-diphenylmethane diisocyanate, a polyol (viscosity 3500 c
Example 1 except that chips were first mixed with a mixture containing 2% of water, 0.15% of a tin-based organic substance as a catalyst, and 1% of silicone oil in ps / 25 ° C, specific gravity of about 1.1). The mixing state of the liquid mixed raw material and the appearance of the urethane foam were examined in the same manner as in the above, and the results are shown in Table 2.

[0033]

[Table 2]

From Tables 1 and 2 above, it can be seen that the production method of the present invention can provide a urethane resin foam with good appearance even when a large amount of solid filler is added.

[0035]

The method for producing a long-fiber-reinforced foamed molded article according to the present invention is constructed as described above, so that it is possible to obtain a high-quality molded article without problems such as poor dispersion of the fixed filler. it can. In addition, a large amount of solid filler can be mixed, and the production cost of the molded article can be reduced. Further, the scattering of dust of the solid filler is eliminated, and the working environment can be favorably maintained.

[Brief description of the drawings]

FIG. 1 is a schematic view of an apparatus used for carrying out a method for producing a long-fiber-reinforced foam molded article according to the present invention.

[Explanation of symbols]

 Reference Signs List A Manufacturing device 5 Spraying device 6 Impregnation device 7 Molding passage 8 Fiber bundle 11 Solid filler 21 Liquid raw material 31 Liquid raw material 51 Foam curable resin

──────────────────────────────────────────────────の Continued on front page (51) Int.Cl. ⁶ Identification code FI B29K 105: 16

Claims (1)

[Claims] 1. A fiber material formed by aligning a large number of long fiber reinforcing materials in one direction continuously advances in the one direction, a liquid raw material containing the compound (A), and a liquid material containing the compound (A). A step of supplying a foam-curable resin liquid obtained by mixing at least another liquid raw material containing the compound (B) that reacts with the compound (A) in the course of the fiber bundle; and supplying the foam-curable resin liquid. A step of rubbing the fiber bundle and impregnating the foam-curable resin liquid between the long fiber reinforcement and the long fiber reinforcement constituting the fiber bundle, and further forming the fiber bundle impregnated with the foam-curable resin liquid And forming the foamable curable resin liquid into a desired shape while foaming and curing the foamable curable resin liquid in the passage. Solid beforehand on the lower liquid material Method for producing a long fiber reinforced foamed molded body characterized by keeping a mixture of Hamazai.