JPH02194949A - Thermosetting resin composition - Google Patents

Abstract

PURPOSE:To form a film or tape reinforced thermosetting resin composition useful for sporting goods, a printed wiring board or writing materials such as a rule by reinforcing the thermosetting resin composition by a film or tape composed of an org. polymer having a specific m.p., specific tensile strength and specific tensile modulus. CONSTITUTION:This material is reinforced by a film or tape composed of an org. polymer having no m.p. of below 300 deg.C, tensile strength of 35kg/mm<2> and tensile modulus of 700kg/mm<2> or more. The film or tape used as a reinforcing tensile material is composed of aramide, polyimide or polybenzbisthiazole. In order to sufficiently develop reinforcing effect, the film or tape and a thermosetting resin pref. have sufficient adhesive strength and the thickness of the film or sheet is pref. about 5-100mum.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to a thermosetting resin composition assisted with a film or tape useful as sports/leisure equipment, printed wiring boards, stationery such as rulers, etc. It is something.

(Prior Art and its Problems) It is known as a conventional technique to use thermosetting resins such as epoxy resins and phenol resins by reinforcing them with carbon fibers, glass fibers, aramid fibers, steel fibers, etc. The reinforcing fibers are used in the form of filament yarns, woven fabrics, staple fibers, and the like.

In order to fully perform its function, reinforcing fibers have high strength and
Depending on the application, high elastic modulus, high compressive strength, etc. are required.
In addition to these, low specific gravity is required.

Incidentally, reflecting recent technological advances, composites are now required to have many functions. For example, even if other properties are met, carbon fibers and carbon whiskers cannot be used due to their electrical conductivity, and it is difficult to make thin composite products of approximately 0.5 mm or less with long fiber reinforcement. Aramid fibers are attracting attention as reinforcing fibers with excellent impact resistance, but when a composite of the aramid fibers is cut or drilled, the aramid fibers are pulled out and the edges cannot be finished neatly, and this is common in long fiber reinforced composites. However, composite products free from these drawbacks have been desired.

Films can be considered to be used as reinforcing materials to create thin-layer composite products with excellent machinability, but films generally have an order of magnitude lower strength and elastic modulus than fibers, and also have a lower strength than matrix resins. It has been considered by those skilled in the art to be unsuitable as reinforcing materials for composites due to the drawback that the bonding interface is relatively small compared to fibers.

(Problems to be Solved by the Invention) The present invention has been made in view of this point, and by using a recently developed film with extremely high tensile strength and tensile modulus, the basic characteristics of the composite are The object of the present invention is to provide a thermosetting resin composition that is comparable to reinforced composites and that can yield a composite that is excellent in thinness, dimensional stability, impact resistance, etc.

(Means for Solving the Problems) That is, the present invention consists essentially of an organic polymer that does not have a melting point below 300°C, and has a tensile strength of 35 kg/mm” or more and a
This is a thermosetting resin composition reinforced with an organic polymer film or tape having a tensile modulus of 00 kg/mm" or more.

In the present invention, the film or tape used as a reinforcing pile member must meet the requirements detailed below.

First, the film or tape must consist essentially of an organic polymer that does not have a melting point below 300°C. The melting point is less than 300°C,
This is undesirable because it melts or thermally deforms during the composite manufacturing process such as curing the resin, and even after it is commercialized, the performance may deteriorate significantly if the usage environment becomes slightly harsh, which is undesirable. Examples of such high melting point organic polymers include aramid, polyimide, polyether ether ketone, wholly aromatic polyester, polybenzimidazole, polybenzibisthiazole, etc. Aramid and polyimide are preferred because of their ease of exhibiting high strength and high modulus of elasticity.
Among them, aramid is preferred. The meaning that the film or tape used in the present invention consists essentially of a specific organic polymer means that components other than the above-mentioned specific organic polymer may be contained in small amounts within the range that does not impair the effects of the present invention. For example, small amounts of organic polymers, organic low-molecular compounds, inorganic compounds, etc. other than those mentioned above may be contained.

Next, the film or tape used in the present invention weighs 35 kg.
/mm2 or more tensile strength and 700 kg/n+m”
It is necessary to have a tensile modulus of elasticity equal to or higher than that. These properties are closely related to the fact that the film or tape functions as a stake member in the thermosetting resin composition in the present invention. In addition, it is a property required to realize a light, thin, short and small product, preferably having a tensile strength of 45 kg/mmz or more, or 1000 kg/mmz or more.
It has a tensile modulus of elasticity of g/mm" or more.

The film or tape may be of a so-called tensilized type, which has increased tensile strength and tensile modulus in the direction required for tensile strength as a composite product. Of course, it is better to use a film or tape that has isotropic performance in that there is no directionality in dimensional stability. In the present invention, it is sufficient that the tensile strength and tensile modulus satisfy the above-mentioned values in at least one direction, but preferably, the average value of the properties in two arbitrarily selected directions orthogonal to each other satisfies the above-mentioned values. It is important to meet the following criteria.

In the present invention, in order to fully express the reinforcing effect,
It is preferable that the film or tape and the thermosetting resin have sufficient adhesive strength. A large adhesive force can be achieved by roughening the surface of the film or tape (devices in film formation, physical or chemical etching after film formation, etc.), or by introducing chemically active species to the surface (corona discharge treatment, plasma treatment, etc.). , chemical decomposition, etc.),
Preferably, methods such as impregnation pretreatment for adhesion (epoxy compound, isocyanate compound, resorcinol/formalin/latex mixture, etc.) or a combination of these are used and achieved.

The thickness of the film or sheet used in the present invention is usually about 5 to 100 μm, preferably 10 to 50 μm.

The thermosetting resin used in the present invention is not particularly limited, and is selected from, for example, epoxy resins, phenol resins, polyimide resins, polyester resins, and the like. In addition, these resins include ultraviolet absorbers, flame retardants, antioxidants, lubricants, colorants, heat stabilizers, anti-aging agents, reinforcing short fibers, reinforcing powders, molding agents, and other ordinary resins. Additives may also be added.

Compositions of the invention can be prepared in a variety of ways. For example, it can be prepared by laminating uncured resin on a film or sheet by coating or dipping, and if necessary, laminating, winding, or shaping the laminate, and then curing it. .

In the present invention, the ratio of the film or sheet to the thermosetting resin is preferably such that the latter is larger in weight than the former, more preferably at least twice as large in weight.

In the composition of the present invention, it is essential to use a film or sheet as a reinforcing material, but if necessary, a fibrous reinforcing material (e.g. filament yarns such as carbon fibers, glass fibers, aramid fibers, etc.) or woven fabrics may be used. etc.) may be used in combination.

The composition of the present invention is put into practical use after being molded into a plate, pipe, rod, or other complex shape.

Example (Manufacture of film) ■Film A An example of manufacturing a roughened aramid film is shown.

Logarithmic viscosity (dissolved in 98% concentrated sulfuric acid, C = 0.5 g
Poly-p-phenylene terephthalamide (measured at 30 °C in 100 ml) of 5.5 was dissolved in 99.5% sulfuric acid at a polymer concentration of 11.8% to form an optically anisotropic dope. Obtained. This was further twisted with nylon 6 so that the total polymer concentration was 12.0%.

This dope was degassed under vacuum and filtered, then extruded through a slit die through a gear pump and cast onto a mirror-polished tantalum belt in an air atmosphere at approximately 90°C with a relative humidity of approximately 40%. The dope was made optically isotropic by passing through the dope, and the dope was introduced together with the belt into a 30% aqueous sulfuric acid solution at -20°C to solidify. The coagulated film was then peeled off from the belt, neutralized with an aqueous solution of caustic soda, and washed with water. Without drying the washed film,
The film was stretched by about 1.15 times in the length direction using rollers, and then 1.4 times in the width direction using a tenter, dried at 200° C. while maintaining the length at a constant length, and further heat-treated at 300° C. for a constant length.

The obtained film was slightly devitrified and had a thickness of 20 μm.
, center line surface roughness 0.16μm, tensile strength 44kg/
-2 (length direction) and 45 kg/cm2 (width direction), tensile modulus of 1350 kg/M'' (length direction) and 1
290 kg/am+'' (width direction), and no transition temperature was observed at temperatures below 500''C even in thermal analysis. From this, the nylon 6 added during dope preparation
was completely eluted during coagulation and washing, resulting in the formation of minute irregularities on the surface and a slight devitrification. This film was also found to have very low creep.

■Film B This film has functional groups introduced into the film surface by plasma treatment.

In the production of film A, the film was produced under exactly the same conditions except that nylon 6 was not additionally twisted.

The resulting film was transparent and had a thickness of 20 μm. The film was then passed continuously through a nitrogen plasma atmosphere to activate both surfaces.

This film has a centerline surface roughness of 0.02μm, a tensile strength of 48kg/2 (longitudinal direction) and 47kg/m
m” (width direction), tensile modulus is 1470 kg/
mm" (length direction) and 1410 kg/w" (width direction)"t', there was no transition temperature below 500°C. This film also had very small creep.

(2) The film is a copolymerized aramid film pre-impregnated with an emulsion dispersion of epoxy resin.

A film was formed in substantially the same manner as Film B using poly-p-phenylene terephthalamide in which 5 mol% of units were copolymerized. However, after washing the film,
It was immersed in an epoxy resin emulsion dispersion (about 4 minutes), then stretched (stretched 1.4 times only in the length direction), dried, and heat treated, but no plasma treatment was performed.

The obtained 20 μm W- film showed only a small leap, had a tensile strength of 63 kg/mm” (longitudinal direction) and 35 kg/mm” (width direction), and a tensile modulus of 2780 kg/mm” (longitudinal direction). ) and 650k
g/mm" (width direction), and did not have a transition temperature below 500°C.

■Film D This film is a polyimide film whose surface has been roughened using SiO□ powder flow.

Ubilex Sj film (25 μm thick), which is commercially available as a polyimide film, was used, and the average particle size was about 0.
．． 5iOz of 5 μm was sprayed onto the film from a nozzle while being mixed and stirred with He gas.

The nozzle was moved over the entire front and back sides of the film to roughen both sides of the film.

The film has a tensile strength of 36 kg/mm" (almost no directionality) and a tensile modulus of 850 kg/mm" (
(almost no directionality), and no transition temperature was observed below 500°C.

(Production of reinforced thermosetting resin composition) Example 1 Film A was immersed in an uncured epoxy resin solution for about 20 to 20 minutes.
It was applied to a thickness of 30 μm. Three sheets of this were laminated and cured at 200° C. for 30 minutes while being pressure-bonded with release paper interposed therebetween, to produce a laminate with a thickness of about 0.2 mm.

This laminate exhibits firm flexibility and has a resistance of 12 to 18 mm/nun/°C (room temperature to 200°C) in any direction.
), it has excellent dimensional stability, has very little directional dependence, and can be easily drilled with a drill, and the periphery of the hole is smooth. In this way, a board suitable for use as a printed wiring board on which semi-flexible electronic components can be mounted was created.

Example 2 Approximately 80μ of uncured epoxy resin was applied to one side of film B.
It was coated with a thickness of 20mm and wrapped uncured around a pipe with a diameter of about 15cm about 20 times, then cured at 150°C for 2 hours, and the pipe for forming was removed. A durable Iff II pipe has been created. This film-reinforced thermosetting epoxy pipe could be easily cut with a wood saw, and the end surface was smooth.

In this way, pipes useful as spawning supplies, etc. (eg, golf club shafts, rackets) and fishing rods were obtained.

Example 3 A thermosetting unsaturated polyester resin composition reinforced with Film C is shown.

Uncured unsaturated polyester (approximately 120 μm thick) was coated on both sides of Film C, and the film was pressed into a mold heated to approximately 350° C. through release paper, and cured while being molded into a dish shape. In this way, a molded body suitable for a three-dimensional wiring board was obtained.

Example 4 Applying uncured phenol resin to both sides of film D,
On the other hand, uncured phenol resin was applied to both sides of the woven fabric made of glass fibers, and while the two were overlapped, 15mmφ
A pipe-shaped prepreg was made by wrapping it around a molding pipe. Next, after curing at 230°C for about 25 minutes, the molding pipe was removed to obtain a pipe with an outer diameter of about 25 mm.

(Effects of the Invention) Since the thermosetting resin composition of the present invention is reinforced with a high-performance organic film, it is possible to create a thinner composite compared to conventional thermosetting resin compositions reinforced with long fibers. It also has excellent machinability and drilling (through-hole machining) properties, and has good dimensional stability as well as excellent isotropy (little difference depending on direction) of dimensional stability.

Moreover, since it uses a high-performance organic film, its tensile, creep, bending, fatigue, heat, and impact resistance properties are comparable to those of fiber-reinforced composites, and there are no problems with adhesion or processability. do not have. In fact, it has the advantage that the processing process is simpler than fiber reinforcement.

The composition of the present invention can be shaped into various shapes by taking advantage of these characteristics, such as golf club shafts, tennis and badminton racket shafts, table tennis rackets, fishing rods, rigid wiring boards, and semi-flexible wiring. It is useful as a substrate, three-dimensional (three-dimensional) wiring board, honeycomb structure material, etc.

Patent applicant: Asahi Kasei Industries, Ltd.

Claims (1)

[Claims] It consists essentially of an organic polymer that has no melting point below 300°C, and has a tensile strength of 35 kg/mm^2 or more and a
Thermosetting resin composition reinforced with an organic polymer film or tape having a tensile modulus of 00 kg/mm^2 or more