JP2000080191A - Foamed molded product of filament reinforced curable resin - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide foamed molded products of a filament reinforced curable resin excellent in mechanical strengths and good in external appearance quality without much increasing a content of a filler. SOLUTION: In the foamed molded products of a filament reinforced resin curable resin comprising a number of filaments arranged in one direction and a filler, the content of the filler is not more than 15%; the expansion ratio is 2.0-4.0 times; and the average particle diameter of the filler is not more than 20% average cell diameter. These foamed molded products can be produced by impregnating a bundle 8 of a number of filaments (a bundle of glass fiber filament and the like) arranged in one direction with a foam curable resin fluid 7 (a foam curable polyurethane fluid and the like) containing a filler 1 (sludge incinerated ash, pulverized quartz sand and the like) and passing the resulting material through a molding passage 63 having a crosssectional shape of a product to simultaneously expand and cure the resin fluid.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a long fiber reinforced curable resin foam molded article suitably used as a lightweight structural material.

[0002]

2. Description of the Related Art A long-fiber reinforced curable resin foamed article containing a large number of long fibers and fillers aligned in one direction has excellent mechanical strength, and is used as a lightweight structural material in place of wood. Widely used for etc.

[0003] This type of long-fiber-reinforced curable resin foamed product is mainly composed of a bundle of long fibers (such as a glass roving bundle) aligned in one direction and a filler (such as glass fiber waste). Is produced by impregnating a foam-curable resin liquid (foam-curable polyurethane liquid or the like) containing the above, passing this through a molding passage having a cross-sectional shape of a product, and foaming and curing the resin liquid ( JP-A-54-37
172 and JP-A-9-39101).

[0004]

The conventional long-fiber-reinforced curable resin foam molded article has a reduced foaming ratio with an increase in the content of the filler, but has an improved mechanical strength, especially a compressive strength. In addition, there is an advantage that the product cost is reduced. However, the filler content cannot be increased too much.

That is, when the content of the filler exceeds about 15% by weight of the product weight, the viscosity of the foaming curable resin liquid impregnated in the bundle of long fibers increases remarkably, and the viscosity of the liquid becomes uniform in the bundle of long fibers. Impregnating it. As a result, the long fibers are not uniformly dispersed in the obtained foamed molded article, and physical properties such as mechanical strength are reduced. In addition, the appearance quality of the product is deteriorated.

The present invention solves the above problems,
It is an object of the present invention to provide a long-fiber-reinforced curable resin foam molded article having excellent mechanical strength and excellent appearance quality without increasing the content of a filler.

[0007]

SUMMARY OF THE INVENTION A long-fiber reinforced curable resin foam molded article of the present invention comprises a long-fiber reinforced curable resin foam molded article containing a large number of long fibers aligned in one direction and a filler. In the above, the content of the filler is 15% or less, the expansion ratio of the foamed resin is 2.0 to 4.0 times, and the average particle diameter of the filler is 20% or less of the average cell diameter of the foamed resin. It is characterized by the following.

The long fiber reinforced curable resin foam molded article of the present invention can be produced by a conventional production method (for example, Japanese Patent Application Laid-Open No. 54-37172).
In the same manner as described in Japanese Patent Application Laid-Open No. 9-39101 and Japanese Patent Application Laid-Open No. 9-39101), a bundle of long fibers aligned in one direction is impregnated with a foam-setting resin liquid containing a filler. Is passed through a molding passage having a cross-sectional shape of a product, and the resin liquid is foamed and cured.

Examples of long fibers include inorganic long fibers such as glass fiber and carbon fiber, and organic long fibers such as aramid fiber, polyester fiber and polyamide fiber. As for the thickness of the monofilaments constituting these long fibers, those having a diameter of 10 to 20 μm are generally suitably used. In particular, glass long fibers are suitable. The content of long fibers is preferably 30 to 50% by weight.

As the filler, sludge incineration ash, crushed silica sand,
Inorganic powders such as glass fiber waste, calcium carbonate, talc, mica, wollastonite, clay, shirasu balloon and pumice, and organic powders such as wood chips, bamboo chips, starch, rice bran and the like can be mentioned. The filler having an average particle size of 10 to 50 μm is preferably used. In particular, sludge incineration ash and pulverized quartz sand are preferable because they can be obtained at low cost.

The content of the filler is not more than 15% by weight,
If the content exceeds 5% by weight, the viscosity of the foam-curable resin liquid impregnated in the bundle of long fibers increases remarkably, and it becomes difficult to uniformly impregnate this into the bundle of long fibers. As a result, the long fibers are not uniformly dispersed in the obtained foamed molded article, and physical properties such as mechanical strength are reduced. In addition, the appearance quality of the product is deteriorated.

As the foam-curable resin liquid, a resin liquid which foams and cures in a relatively short time, for example, a foam-curable polyurethane resin liquid, a phenol resin liquid, a polyester resin liquid or the like is used. In particular, a foam-curable polyurethane resin liquid is preferred.

As such a foam-curable polyurethane resin liquid, for example, a polyol having 3 to 4 functional groups,
A foam-curable polyurethane resin liquid comprising a polyisocyanate such as diphenylmethane diisocyanate (MDI) or modified MDI and a foaming agent such as water or chlorofluorocarbon is preferably used. In this case, the average cell diameter of the foamed resin is 8
Those having a size of about 0 to 250 μm are obtained.

The expansion ratio of the foamed resin is set to 2.0 to 4.0 times, and the average particle diameter of the filler is set to 20% or less of the average cell diameter of the foamed resin. If the expansion ratio of the foamed resin is lower than 2.0 times, the lightness of the obtained foamed molded article is impaired, and it is not suitable for a lightweight structural material replacing wood.

Conversely, when the expansion ratio of the foamed resin is higher than 4.0 times, or when the average particle diameter of the filler is larger than 20% of the average cell diameter of the foamed resin, the cell wall of the foamed resin is reduced. It becomes thinner, and the probability that the filler is embedded in the cell wall becomes very low, the reinforcing effect of the cell wall is not so much exhibited, and the mechanical strength, particularly the compressive strength, of the obtained foamed molded article is reduced. .

Here, the expansion ratio and cell diameter of the foamed resin are as follows:
It is adjusted mainly by the type and amount of a foaming agent such as water and Freon gas and the content of a filler.

[0017]

The foaming curable resin liquid having a filler content of 15% by weight or less has a small increase in viscosity and can be uniformly impregnated into a bundle of long fibers. When the expansion ratio of the foamed resin is 2.0 to 4.0 times and the average particle diameter of the filler is 20% or less of the average cell diameter of the foamed resin, the state in which the filler is embedded in the cell wall is obtained. Is very likely to fit in
As a result, the effect of reinforcing the cell walls with the filler is increased.

Further, when the average particle size of the filler is relatively small as described above, it is easy to be uniformly dispersed among the long fibers, and the variation in specific gravity and the variation in mechanical strength of the whole product are reduced. Appearance quality is also improved.

[0019]

Next, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is an explanatory view showing a method for producing a long fiber reinforced curable resin foam molded article of the present invention. In FIG. 1, A is a manufacturing apparatus, which includes a hopper 11, a belt feeder 12, an extruder 4 with a built-in screw, a pump 43,
First raw material tank 21, pump 22, second raw material tank 3
1, pump 51, mixing and spraying device 5, kneading plates 61, 61,
An impregnated plate 62 is provided with a molding passage 63 having a first half heating section and a second half cooling section.

First, the filler 1 is put in the hopper 11,
This is supplied to the extruder 4 via the belt feeder 12. At the same time, the first liquid raw material (polyol liquid containing a foaming agent) 2 is put into the first raw material tank 21,
To the extruder 4 via

The filler 1 and the first liquid raw material 2 supplied to the extruder 4 are uniformly mixed by the rotation of the screw of the extruder 4, and are supplied to the mixing and spraying device 5 through the pump 43. At the same time, the second liquid raw material (polyisocyanate) 3 is put in the second raw material tank 31, and the second liquid raw material (polyisocyanate) 3 is supplied to the mixing and spraying device 5 via the pump 51 in a constant amount.

In the mixing and spraying device 5, the first liquid raw material 2 and the second raw material 3 mixed with the filler 1 are uniformly mixed to prepare a foam-curable resin liquid (foam-curable polyurethane liquid) 7. Is done. The foam-curable resin liquid 7 is sprinkled from the discharge port of the mixing and spraying device 5 onto the fiber bundle 8 of long fibers.

The fiber bundle 8 of the long fibers to which the foaming-curable resin liquid 7 has been sprinkled is rubbed between the rubbing plates 61, 61 and the impregnated plate 62, and between the long fibers 81 constituting the fiber bundle 8. The foam-curable resin liquid 7 is uniformly impregnated. At this time, the filler 1 dispersed in the first liquid raw material 2 is also uniformly dispersed.

Fiber bundle 8 impregnated with foam-setting resin liquid 7
Is transferred to the molding passage 63 and is advanced.
The foaming-curable resin liquid 7 foams and hardens in 3 to continuously obtain a long-fiber precurable resin foam molded article of the present invention having a cross-sectional shape along the inner wall surface of the molding passage 63.

Hereinafter, examples and comparative examples of the present invention will be described. (Examples 1 to 6 and Comparative Examples 1 to 4) A fiber-reinforced curable resin foam molded article was produced by the method shown in FIG. As the first liquid raw material 2, 100 parts by weight of propylene oxide-added polyether polyol having 4 functional groups, 1 part by weight of distilled water as a blowing agent, and monofluorotrichloromethane (R-1)
1) A polyol mixture was prepared by mixing 3 parts by weight, 1 part by weight of silicone oil (release agent) and 0.2 part by weight of dibutyltin dilaurate as a catalyst. Also, the second liquid material 3
Was used to prepare crude diphenylmethane diisocyanate.

Further, as filler 1, crushed silica sand (average particle size 30 μm, specific gravity 2.6), sludge incineration ash (average particle size 1
5 μm, specific gravity 2.2) and silica sand No. 7 (average particle size 150 μm)
m, specific gravity 2.6). Further, as the long fiber bundle 8, a glass roving bundle in which a large number of monofilaments having a fiber diameter of 13 μm were prepared was prepared.

Using the first liquid raw material 2, the second liquid raw material 3, the respective fillers 1 and the long fiber bundle 8, the production conditions are appropriately changed and the method shown in FIG. A closed-cell, long-fiber reinforced curable resin foam (75 m thick)
mx 240 mm) were manufactured continuously. For these foamed molded articles, the appearance of the product, apparent specific gravity, specific gravity distribution, expansion ratio of foamed resin and average cell diameter were measured. Table 1 shows the results.

The appearance of the product was evaluated as "O" when the appearance was almost the same as that of the foamed molded products obtained in Comparative Examples 1 and 3, and the product was inferior to that (a color unevenness and perforations were conspicuous).
Indicated as Δ.

The specific gravity distribution of the product was determined by cutting out the foamed molded article (thickness: 75 mm × width: 240 mm) in order of 22 mm square to obtain sample pieces, and measuring the specific gravities of these sample pieces. The one having a specific gravity distribution substantially equal to the specific gravity distribution of the foamed molded article obtained in Step 3 is represented by ○, the one having a large variation in specific gravity is represented by △, and one having a small variation in specific gravity (within ± 5% of the set specific gravity) ) Are indicated as ◎.

Further, regarding the obtained foamed molded product, the bending strength (JIS Z 2113), the compressive strength (lateral direction)
(JIS Z 2111) and shear strength (JIS Z
2114) was measured. Table 1 shows the results.

[0031]

[Table 1]

[0032]

As described above, the long fiber reinforced curable resin foam molded article of the present invention comprises a long fiber reinforced curable resin foam molded article containing a large number of long fibers aligned in one direction and a filler. In the above, the content of the filler is 15% by weight or less,
The expansion ratio of the foamed resin is 2.0 to 4.0 times, and the average particle diameter of the filler is 20% or less of the average cell diameter of the foamed resin, thereby increasing the content of the filler too much. In other words, even if the content of the filler is 15% by weight or less, a product excellent in mechanical strength can be obtained.

In addition, when the average particle size of the filler is relatively small, it is easy to disperse uniformly between the long fibers, the variation in specific gravity and mechanical strength is reduced, and a product having good appearance quality can be obtained. .

[Brief description of the drawings]

FIG. 1 is an explanatory view showing a method for producing a long fiber reinforced curable resin foam molded article of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Filler 2 1st liquid raw material (polyol liquid containing foaming agent) 3 2nd liquid raw material (polyisocyanate) 4 Extruder 5 Mixing and spraying device 7 Foam curable resin liquid 8 Long fiber bundle (bundle of glass roving) 61 Rubbing plate 62 Impregnated plate 63 Molding passage

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI theme coat ゛ (reference) B29K 105: 08 105: 16 309: 08 F term (reference) 4F074 AA78 AA97 AC34 AC36 AE01 AE04 AG01 BA34 BA53 CA12 DA02 DA03 DA08 DA50 4F205 AA32.

Claims (1)

[Claims] 1. A long-fiber-reinforced curable resin foamed molded article containing a large number of long fibers and a filler aligned in one direction, wherein the filler content is 15% by weight or less, and A long-fiber-reinforced curable resin foam molded article having an expansion ratio of 2.0 to 4.0 times and an average particle diameter of a filler of 20% or less of an average cell diameter of a foamed resin.