JPH0449028A - Manufacture of fiber-reinforced foamed phenol molded form - Google Patents

Abstract

PURPOSE:To increase bending and peel strength, and to obtain a light-weight strong molded form by heating and pressure-molding a felty article and expanding a thermoplastic foaming resin permeated among fibers and a phenol resin containing a foamable material which the gaps among fibers are filled closely with the foamed thermoplastic resin and the phenol resin. CONSTITUTION:Bulky fibers 1 are laid on a table T, and a proper quantity of a mixture 2, in which a foaming agent and a thermoplastic foaming resin are mixed with a phenol resin, are sprinkled over the fibers 1. It is favorable that the 3-10 pts. wt. foaming agent and the 3-30 pts. wt. thermoplastic foaming resin are mixed with the 100 pts. wt. phenol resin as the composition of the mixture at that time. When the table T is vibrated, the mixture 2 is permeated into the fibers 1, and distributed over the fibers 1. When the mixture 2 is distributed into the fibers 1 approximately uniformly, the fibers are heated temporarily by a heating means such as a heating coil 3. Accordingly, the mixture 2 is melted, and a primary molded form 4 in which the fibers 1 are distributed equally can be manufactured. When the primary molded form is moved up to a heating pressure means HP from the table T and heated and pressured, the mixture is foamed uniformly.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a method for producing a fiber-reinforced foamed phenol molded product that is suitably used as interior materials for automobiles, furniture, interior and exterior materials for buildings, and the like.

[Prior Art] Automotive interior materials, furniture, interior and exterior materials for buildings, etc. are required to be lightweight, flame retardant, soundproof, heat insulating, processable, and stronger than a specified level. Fiber-reinforced foamed phenol moldings are examples of molding materials that may satisfy these various physical properties.

As for conventional fiber-reinforced foamed phenol molded products,
There are those made of thermosetting resin foam, and those in which non-sublime fibers are added or coated onto the surface of a foamed resin base.

[Problems to be Solved by the Invention] However, conventional fiber-reinforced foamed phenol molded products made of thermosetting resin foams have poor elasticity and are easily crushed, especially by local stress, and are susceptible to scratches and chafing. It has a major disadvantage that the hardened resin from the surface turns into powder and drips down. It is inappropriate to use materials with such defects in automobile interior materials, furniture, architectural interior and exterior materials, etc., and it may have a negative impact on the mental or physical health of the users inside the materials. .

On the other hand, simply coating or coating the foamed resin with non-sublime fibers does not allow the resin to penetrate sufficiently between the individual fibers. As a result, the resin layer and fiber layer clearly separate after firing,
Alternatively, if the fiber layer is multi-layered, there will be a portion where the fibers are not entangled. When a load is applied to such a material, especially when the stress generated during bending or peeling acts on the foam layer (the part that is not reinforced with fibers and has weak strength),
Since it is not reinforced with fibers, it is extremely susceptible to breakage.

Therefore, there is a problem that the strength of the entire material decreases.

The present invention has been proposed in view of the problems of the prior art described above, and is capable of manufacturing fiber-reinforced foamed phenol molded products suitable for use as interior materials for automobiles, furniture, interior and exterior materials for buildings, etc. The purpose is to provide a method.

[Means for solving the problems] The method for producing a fiber-reinforced foamed phenol molded product of the present invention includes:
A step of spraying a mixture of a blowing agent and a thermoplastic foam resin mixed with a phenolic resin on the upper surface of the sublime fibers, and a step of applying vibration to cause the mixture to penetrate into the fibers to form a felt-like material. The felt-like material is heated and pressurized to expand the thermoplastic foam resin and the phenolic resin containing the foaming agent that have penetrated between the fibers, and It is characterized by filling the foamed thermoplastic foam resin and phenol resin without any gaps between the fibers.

In carrying out the present invention, the phenol resin is preferably a novolak type phenol resin containing a curing agent such as ordinary hexamine, or a resol type phenol resin.

Further, in order to foam the phenol resin, it is preferable to use a thermoplastic foamed resin, and use a usual foaming agent such as sodium bicarbonate, ammonium carbonate, dinitrosopentamethylenetetramine, etc. as an aid.

It is preferable that the felt-like material is primarily heated prior to the step of further heating and pressurizing. - This is because the second heating makes handling of the felt-like material extremely easy.

Note that chemical fibers, natural fibers, inorganic fibers, etc. can be used as the bulky fibers.

[Function] According to the present invention having the above-described structure, the fibers are uniformly distributed throughout the molded product, so the strength is greatly improved and there is no fear that weak parts will be scattered. In the present invention, since a noble material is used as the reinforcing fiber, the foamed resin is sufficiently dispersed in the multi-fibers, and even if the fiber layers are made into multiple layers, the fibers do not come into contact with each other between each fiber layer. There is some confounding.

Therefore, the edges between each fiber are not cut off and the fibers are not completely separated. When the resin foams, the foamed resin is evenly filled between each fiber, so the composition of the molded product becomes homogeneous.
Partially weak points are eliminated.

As a result, the physical properties of the molded article, especially the bending and peel strength, are significantly improved, and a lightweight and durable molded article can be obtained.

Furthermore, since the main blowing agent of the molded product produced according to the present invention is a thermoplastic foamed resin, the bubbles after foaming become uniform, and elasticity is imparted to the foamed molded product. In addition, since the phenol resin has flame retardancy, the molded product also has flame retardancy.

Here, if a foaming agent is simply mixed into the phenol resin, the surface of the molded product becomes extremely brittle after foaming, resulting in a so-called "tattered state." However, according to the manufacturing method of the present invention, the thermoplastic foam resin acts as a binder, so that the molded product becomes homogeneous. As a result, powder dripping from the surface of the foam molding, which was a major drawback in the prior art, is prevented.

As described above, according to the manufacturing method of the present invention, lightweight, flame retardant,
Molded products with very good properties such as soundproofing, heat insulating properties, workability, and strength can be obtained, and are suitably used for automobile interior materials, furniture, interior and exterior materials for buildings, etc.

In addition, according to the manufacturing method of the present invention, the molded product contains multiple types of blowing agents, which expands the range of foam molding conditions and provides fiber-reinforced foamed phenol molded products with various properties. This will result in

[Example code] Examples of the present invention will be described below.

First, various steps in the manufacturing method of the present invention will be explained with reference to the drawings.

First, as shown in FIG. 1, bulky fibers 1 are laid on a table T. As shown in FIG.
Sprinkle an appropriate amount on top.

Here, the composition of mixture 2 is, for example, phenol resin 100%
It is preferable to mix 3 to 10 parts by weight of a blowing agent and 3 to 30 parts by weight of a thermoplastic foam resin. 3 foaming agents
If the amount is 10 parts by weight, a good molded product can be obtained in balance with the thermoplastic foam resin. In addition, if the amount of thermoplastic foam resin is small, the molded product will become crumbly, and if the amount is too large, flame retardancy will not be obtained.

When the table T is then vibrated, the mixture 2 penetrates into the fibers 1 and is distributed within the fibers 1, as shown in FIG. Note that the vibrations applied to the table T may be horizontal vibrations as shown by the arrow H, or vertical vibrations as shown by the arrow ■.

Once the mixture 2 has been distributed approximately uniformly into the fiber 1, the fourth
As shown in the figure, primary heating is performed by heating means such as a heating coil 3. The mixture 2 is melted by this secondary heating, and a primary molded product 4 in which the fibers 1 are uniformly distributed is completed.

This second molded product 4 has a felt shape, and is moved from the table T to the heating and pressurizing means HP and heated and pressurized to complete the molded product (FIG. 5). In this heating and pressurizing process, uniform foaming is performed. (It is also possible to omit the step of performing the primary heating shown in Fig. 3.) It is also possible to laminate a plate made of paper or a material such as high-density glass fiber on the second molded product 4 and heat it. Pressing improves the strength of the molded product.

Here, the heating temperature and heating time in the heating and pressing step are as follows:
The temperature and time are such that the thermoplastic foam resin foams and the cells do not become rough due to abnormal foaming, specifically 1.
It is set for 1 minute to 10 minutes at 40 degrees Celsius to 200 degrees Celsius. Further, the pressure is set within a range such that the mold is not lifted up due to gas generation.

If it is desired to increase the thickness of the molded product, it is sufficient to stack a plurality of layers of fibers 1 as shown in FIG. 6, mix the mixture 2 into each layer, and stack the fibers 1 on top of each other. In addition, in Fig. 6, a void is shown between the layers of fiber 1. This is an expression to indicate that a plurality of fibers 1 are stacked on top of each other, and in reality, a void is formed between one layer of fiber. There's no need.

Note that although long fibers are used in the illustrated example, it is also possible to use relatively short glass fibers or the like.

Examples in which more specific limitations are applied to materials, numerical values, etc. will be described below.

Example 1 Glass fiber, especially rC5MJ (continuous strand mat) manufactured by Asahi Fiber Class, or rCMJ (chopped strand mat) manufactured by Asahi Fiber Class, was used as the bulky fiber 1, and Matsumoto Resin Pharmaceutical Co., Ltd. was used as the thermoplastic foam resin. A mold with the trade name "Matsumoto Microsphere-F-50J" was used. This thermoplastic foam resin is made by adding foaming gas to vinylidene chloride or acrylonitrile resin to inflate it.

A sublime base material formed into a mat of continuous glass fibers having an areal density of 300 g/m is layered on a chopped mat of glass fibers having an areal density of 330 g/lri,
On top of that, 8% phenolic resin mixed with 20% thermoplastic foam resin and 5% dinitrone pentamethylene diamine was added.
Apply at a rate of 0.00 g/rri. When vibration is applied, the resin is sufficiently dispersed between the sublime fibers. after that,
15 while maintaining a distance of 5 m at a pressure of 10 kg/al.
A fiber-reinforced foamed phenol molded product was produced by thermoforming at 0°C for 2 minutes.

The density of the fiber-reinforced foamed phenol molded product thus obtained is 0.2. Regarding bending strength, JIS
Measurements were made with the chopped strand mat facing upward in accordance with the General Test Method for Thermosetting Plastics of K-6911. As a result, the bending strength is 0.7 to 0.8 kg/ff.
1I112, which is a 20-30% improvement over non-sublime glass fiber reinforced moldings of comparable areal density.

The bending disconnection rate is 60 kg/mm' and 0. 5kg/
It did not break even after repeated application of external bending force 40 times with a load of 1 m2. However, moldings reinforced with non-sublime glass fibers of comparable areal density were destroyed (destruction of the foamed resin layer) by one bend.

No dripping of resin powder was observed on the surface of the molded product. In addition, the foam layer has uniform cells without any roughness.

Example 2 A phenolic resin containing 10% thermoplastic foam resin and 50% dinitrosopentamethylenediamine is applied at a rate of 700 g/m onto a mat of natural palm rock fibers having an areal density of 500 g/nf. . When vibration is applied, the applied resin is thoroughly dispersed between the sublime fibers. Thereafter, while maintaining the interval of 51I11 as the thickness dimension, a fiber-reinforced foamed phenol molded product is manufactured by heat-pressing molding at 150° C. for 2 minutes at a pressure of 10 kg/al.

The density of this molded product is 0.2. The bending strength was measured in accordance with JIS K-6911 general test method for thermosetting plastics. As a result, the bending strength is 0
．． 6-0. It is 7 kg/mm2.

The bending elastic modulus was 40 kg/mm2. Even after repeated bending 40 times at a strength of 0.4 kg/mm2, it did not break. Further, no dripping of resin powder was observed on the surface of the molded product. In addition to this, the foam layer has uniform cells without any roughness.

[Effects of invention The effects of the present invention described above are listed below.

(1) Since the fibers are uniformly distributed throughout the molded product, the strength is greatly improved, the composition of the molded product is homogenized, and there are no weak spots. As a result, the physical properties of the molded product,
In particular, bending and peel strength are significantly improved, and a lightweight and durable molded product can be obtained.

(2) Since the thermoplastic foam resin acts as a binder, powder is prevented from dripping from the surface of the foam molding.

(3) A molded product with excellent properties such as lightness, flame retardancy, soundproofing, heat insulation, workability, and strength can be obtained, making it suitable for automobile interior materials, furniture, interior and exterior materials for buildings, etc. used.

(4) The range of foam molding conditions will be expanded, and fiber-reinforced foamed phenol molded products with various properties will be provided.

(5) The strength of the molded product can be improved by laminating a plate made of paper or a material such as high-density glass fiber on the surface of the molded product.

[Brief explanation of drawings]

1 to 5 are side views in which various steps in one embodiment of the present invention are arranged in chronological order, and FIG. 6 is a side view showing another embodiment of the present invention. 1...Fiber 2...Mixture 3...-Next heating means 4...-Next molded product HP...Heating and pressing means T
...Table 1 5 @ 31st! 1 Bleaching 6 @

Claims (1)

[Claims] A step of spraying a mixture of a blowing agent and a thermoplastic foam resin mixed with a phenolic resin on the upper surface of the sublime fibers, and a step of applying vibration to cause the mixture to penetrate into the fibers to form a felt-like material. The felt-like material is heated and pressurized to expand the thermoplastic foam resin and the phenolic resin containing the foaming agent that have penetrated between the fibers, and A method for producing a fiber-reinforced foamed phenol molded product, which comprises filling foamed thermoplastic foamed resin and phenolic resin without gaps between the fibers.