JPH1015982A - Polynorbornene-based resin molded article and method for producing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a polynorbornene-based resin molded article which has less cracking and distortion due to uneven distribution of reinforcing fibers, has excellent strength properties, and is inexpensive to produce, and a method for producing the same. To provide. SOLUTION: A reinforcing fiber is adhered as a reinforcing material to at least a part of the surface of the polynorbornene-based resin molded product. When molding a polynorbornene-based resin molded product by reaction injection molding, a first mold and a second mold are used as molds, and the temperature of the second mold is set higher than the temperature of the first mold. And, of the surface of the molded product obtained by reaction injection molding,
A reinforcing fiber is adhered to at least a part of the surface of the molded product at a portion in contact with the first mold set at a low temperature using an adhesive.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polynorbornene-based resin molded article and a method for producing the same, and more particularly, to a molded article having less cracking and distortion due to uneven distribution of reinforcing fibers and having excellent strength. The present invention relates to a polynorbornene-based resin molded article and a method for producing the same.

[0002]

2. Description of the Related Art Concrete molded products and metal molded products have disadvantages such as heavy weight and difficulty in cutting, and in recent years, molded products conventionally formed of metal or concrete have been made of synthetic resin. There are many attempts to mold.

In particular, polynorbornene-based resin molded products (RI) obtained by reaction injection molding of norbornene-based monomers
M) is considered to be used in various technical fields because it has excellent impact resistance and is easy to form a large molded body.

[0004] However, depending on the use and size of the molded product, in some parts of the molded product, the polynorbornene-based resin molded product alone may not be able to satisfy the required strength specifications.

In such a case, at the time of reaction injection molding, reinforcing fibers such as reinforcing fibers are arranged in a mold, and the reinforcing fibers are incorporated by performing reaction injection molding in the mold. A polynorbornene-based resin molded product is manufactured to improve the mechanical strength of the obtained molded product.

[0006]

However, the RIM
In a molded product, it is difficult to partially fill the molded product with the reinforcing fiber, and it is necessary to fill the entire molded product with the reinforcing fiber. Therefore, the manufacturing cost is increased.

[0007] Even if reinforcing fibers such as glass fibers can be embedded only in a part of the RIM molded article, unevenness of the reinforcing fibers at the interface between the part where the reinforcing fiber exists and the part where the reinforcing fiber does not exist. Depending on the distribution, very low physical properties may be generated, and the molded product may be easily cracked or distorted, which may have an adverse effect.

The present invention has been made in view of the above-mentioned circumstances, and has low cracking and distortion due to non-uniform distribution of reinforcing fibers, has excellent strength, and is inexpensive to manufacture. An object of the present invention is to provide a molded article and a method for producing the same.

[0009]

In order to achieve the above-mentioned object, a polynorbornene-based resin molded product according to the present invention is provided on at least a part of the surface of the polynorbornene-based resin molded product.
The reinforcing fiber is bonded as a reinforcing material.

The method for producing a polynorbornene-based resin molded product according to the present invention uses a first mold and a second mold as molds when molding the polynorbornene-based resin molded product by reaction injection molding. The temperature of the second mold is set higher than the temperature of the first mold, and the molded product at the portion of the surface of the molded product obtained by the reaction injection molding, which is in contact with the first mold set at a lower temperature. The reinforcing fiber is bonded to at least a part of the surface of the substrate using an adhesive.

The reinforcing fiber used here includes, for example, a reinforcing fiber and a nonwoven fabric, but preferably a reinforcing fiber. These reinforcing fibers may be used alone.
A combination of more than two types may be used.

The reinforcing fiber may be a continuous fiber, a long fiber or a single fiber, but when high rigidity and high strength are required, it is preferably used in the form of a continuous fiber or a long fiber. Examples of the form of such continuous fibers or long fibers include, for example, a cloth having a random arrangement such as cloth fabric, filament winding, and continuous strand mat.

The reinforcing fibers are not particularly limited,
Carbon fiber, glass fiber, alumina fiber, silicon carbide fiber,
Steel fiber, amorphous metal fiber, aramid fiber,
Inorganic or organic fibers such as boron fiber, vinylon fiber, polyacrylate fiber, acrylic fiber, polyester fiber, high-strength vinylon fiber (polyvinyl alcohol fiber), nylon fiber, or a mixture of these fibers, and carbon fiber, Glass fibers, aramid fibers, high-strength vinylon fibers, and nylon fibers are preferable, and carbon fibers and glass fibers are more preferable.

In the present invention, the fiber diameter of the reinforcing fibers is not particularly limited, but is preferably about 3 to 170 μm.

In the present invention, a nonwoven fabric may be used together with the reinforcing fibers or alone. As the nonwoven fabric, for example, glass fiber paper, carbon fiber paper, polyester nonwoven fabric, nylon nonwoven fabric, vinylon nonwoven fabric,
Polyphenylene sulfide nonwoven fabric, acrylic nonwoven fabric and the like are used, glass fiber paper, carbon fiber paper, and vinylon nonwoven fabric are preferable, and glass fiber paper and carbon fiber paper are more preferable.

As an adhesive for bonding such a reinforcing fiber to a molded article as a reinforcing material, epoxy, urethane, acrylic, rubber, polyester, vinyl acetate, polyamide, ethylene-vinyl acetate Adhesives such as copolymers and cyanoacrylates are conceivable, but in consideration of the adhesiveness with polynorbornene resins and economics, epoxy, urethane, acrylic, vinyl acetate, and cyanoacrylate adhesives are considered. Are more preferable, and epoxy-based and cyanoacrylate-based are more preferable.

The adhesive may be applied to the surface of the molded article or the reinforcing fibers by means such as brushing or spraying, or the reinforcing fibers may be impregnated with the adhesive.

In the present invention, since the reinforcing fiber is not filled in the inside of the molded product, the uneven distribution of the reinforcing fiber at the interface between the portion where the reinforcing fiber is present and the portion where the reinforcing fiber is not present is obtained.
A resin part having low physical properties is not generated, and there is no possibility that a crack or distortion occurs in the molded product. Further, in the present invention, only the portion to be reinforced can be very easily reinforced, so that the amount of reinforcing fibers used can be reduced, and the cost of the molded product can be reduced. In addition, it was also confirmed that the strength of the molded article according to the present invention was extremely good as compared with a molded article in which reinforcing fibers were filled inside the molded article.

In producing the polynorbornene-based resin molded product according to the present invention, the surface of the molded product may be subjected to a primer treatment before the reinforcing fibers are bonded using an adhesive. In the primer treatment, for example, a coupling agent such as a silane coupling agent is used. By performing the primer treatment, the adhesion to the RIM molded product is improved. In addition, the use of this primer treatment increases the types of adhesives that can be used for RIM molded products.

In the present invention, the mold used in the reaction injection molding of the RIM molded article is not particularly limited, and need not necessarily be a highly rigid and expensive mold, and is not limited to a metal mold. A mold making or a simple mold can be used. However, as the mold preferably used in the present invention, a first mold and a second mold are used, and the temperature of the second mold is set higher than the temperature of the first mold, preferably 10 to 50 ° C. It is more preferable to set the temperature higher by about 20 to 30 ° C. The temperature of the first mold is preferably 30 to 70 ° C, more preferably 40 to 60 ° C.
° C.

In the reaction injection molding in which the temperature of the mold is changed as described above, the second mold and the first mold are used.
The mold is made of a material having a different coefficient of linear expansion.
It is further preferable that the mold is made of a material such that the absolute value of the thermal expansion amount of these molds becomes substantially equal due to the temperature difference between the mold and the first mold. The combination of such materials is a combination in which the first mold is a cast aluminum mold and the second mold is an electroformed mold in which a refractory metal layer of nickel or the like is lined with resin. The resin con- trol is a concrete mold containing resin and aluminum powder.

The first mold is a cast aluminum mold, and the second mold is
When the mold is a nickel-plated electroformed mold, the respective coefficients of linear expansion are α ₁ = 23 × 10 ⁻⁶ / ° K, α ₂ =
13.3 × 10 ⁻⁶ / ° K. Assuming a room temperature of 10 ° C, the first mold made of cast aluminum was set at 45 ° C,
Assuming that the second mold made of nickel-plated electroforming was set at 70 ° C., and the respective linear expansion degrees were obtained, the first mold showed that
α ₁ × (45−10) = 8.05 × 10 ⁻⁴ and the second
In the mold, α ₂ × (70−10) = 7.98 × 10 ⁻⁴ , and both are almost equal. Therefore, even if a temperature difference is provided between the first mold and the second mold, the absolute amounts of thermal expansion of the two molds are substantially equal, and the dimensional accuracy of the molded product is not adversely affected.

As described above, by performing reaction injection molding by providing a temperature difference between the two dies and obtaining a RIM molded product, a smooth skin layer is formed on the surface of the molded product in contact with the high-temperature mold. On the surface of a molded product in contact with a mold having a low temperature, a fine rough surface is formed.

In the present invention, the adhesion of the reinforcing fiber to the polynorbornene-based resin molded article is improved by bonding the reinforcing fiber to the fine rough surface side other than the skin layer via an adhesive.

In the present invention, when it is desired to form a skin layer on the outer surface of the molded article and form a fine rough surface on the inner surface of the molded article, the first mold is a convex mold (core mold). Preferably, the second mold is a concave mold (cavity mold).
When it is desired to form a skin layer on the inner surface of a molded article, the opposite is preferable.

The norbornene monomer preferably used in the reaction injection molding in the present invention is, for example, a cycloolefin having a norbornene ring such as dicyclopentadiene, dihydrodicyclopentadiene, tetracyclododecene, tricyclopentadiene and the like.

A metathesis catalyst that can be used in reaction injection molding using a norbornene-based monomer is
For example, there is no particular limitation as long as it is a metathesis catalyst known as a catalyst for bulk polymerization of norbornene-based monomers such as organic ammonium molybdates such as tungsten hexachloride, tridodecyl ammonium molybdate, and tri (tridecyl) ammonium molybdate. Organic ammonium molybdate is preferred.

Examples of the activator (cocatalyst) include alkylaluminum halides such as ethylaluminum dichloride and diethylaluminum chloride, alkoxyalkylaluminum halides, and organotin compounds.

As preparations for the reaction injection molding, a reaction injection molding material mainly composed of a norbornene-based monomer, a metathesis catalyst and an activator was used as a liquid A composed of a norbornene-based monomer and a metathesis catalyst; Divided into two stable liquids, liquid B and activator,
Keep each in a separate tank. At the time of reaction injection molding, these two liquids are mixed in a mixing chamber, and then the mixed liquid is poured into a cavity of a mold and subjected to bulk polymerization to obtain a molded article.

At the time of reaction injection molding, the mold clamping pressure is usually in the range of 0 to 100 kg / cm ² . The polymerization time may be appropriately selected, but is usually 30 seconds to 20 minutes after the completion of the injection of the reaction solution.

The use of the polynorbornene-based resin molded product according to the present invention is not particularly limited. For example, it is used for a CT scan casing cover, a car bumper, a helmet and other protective equipment. It is preferable that the reinforcing fibers be adhered to portions of these molded articles which are not visible from the outside.

[0032]

EXAMPLES Hereinafter, the present invention will be described with reference to more specific examples, but the present invention is not limited to these examples. In the following description, parts or% are based on weight unless otherwise specified.

Example 1 A polynorbornene-based resin molded product having a width of 50 mm, a length of 200 mm and a thickness of 5 mm was produced by reaction injection molding. In reaction injection molding, dicyclopentadiene (DC
P) 90% and asymmetric cyclopentadiene trimer 10%
Are placed in two containers, one of which has diethylaluminum chloride (DEAC) in a molar concentration of 40 moles based on the monomer and 1,3-dichloro-
2-Propanol (dcPrOH) was added to a concentration of 48 mol (solution A). On the other hand, for the monomer,
Tri (tridecyl) ammonium molybdate was added to a concentration of 10 mmol (Solution B). These A liquid and B liquid were stored in A tank and B tank, respectively.

The temperature of the cast aluminum mold was set to 45 ° C. by flowing hot water through a heat medium flow passage mounted inside the cast aluminum mold and the electroformed mold having a nickel plating layer. The temperature of the electroformed mold was set to 70 ° C. The same volume of A is introduced into the mold cavity from the injection port.
Liquid and liquid B are mixed and injected, and after about 5 minutes,
A reaction injection molded product (polynorbornene-based resin molded product) was taken out of the mold.

Observation of one surface of the molded product (the surface in contact with the electroformed mold) confirmed that a skin layer had been formed. When the other surface (the surface in contact with the cast aluminum mold) was observed, a fine rough surface was observed.
An epoxy adhesive (manufactured by Nippon Ciba Geigy Co., Ltd., main material Y)
5052, cured material Y5052) previously impregnated with carbon fibers (manufactured by Toho Rayon Co., Ltd., basis weight 22 g /
m ² , thickness 0.35 mm, plain weave), dried at room temperature for 24 hours, and after-cured at 60 ° C. to 70 ° C. for 30 minutes. The sample thus obtained was cut out to a width of 15 mm and a length of 90 mm, and subjected to a bending test.
Flexural strength and flexural rigidity were determined. Table 1 shows the results.

[0036]

[Table 1]

Example 2 As an adhesive, an adhesive MEZ6 manufactured by Zeon Rise Co., Ltd.
Example 1 except that 90CL (epoxy type) was used.
A sample was prepared and a bending test was performed in the same manner as described above.
Table 1 shows the results.

Example 3 A sample was prepared and subjected to a bending test in the same manner as in Example 1 except that an adhesive FR-E3P (epoxy type) manufactured by Tonen Corporation was used as the adhesive. Table 1 shows the results
Shown in

Example 4 As an adhesive, an adhesive Y-1 manufactured by Tokyo Hamatite Co., Ltd.
A sample was prepared and subjected to a bending test in the same manner as in Example 1 except that 700-A (urethane-based) was used. Table 1 shows the results.

Example 5 An adhesive FR-E3P (epoxy type) manufactured by Tonen Co., Ltd. was used as the adhesive, and unidirectional fiber of a weight of 300 g / m ² and a thickness of 0.17 mm manufactured by Tonen Co., Ltd. was used as the carbon fiber. A sample was prepared and subjected to a bending test in the same manner as in Example 1 except that was used. Table 1 shows the results.

Example 6 As a reinforcing fiber, a glass fiber roving cloth WR860B-100 manufactured by Nitto Boseki Co., Ltd. (basis weight 86
A sample was prepared and subjected to a bending test in the same manner as in Example 1 except that 0 g / m ² ) was used. Table 1 shows the results
Shown in

Example 7 As a reinforcing fiber, vinylon fiber F manufactured by Kuraray Co., Ltd. was used.
A sample was prepared and subjected to a bending test in the same manner as in Example 1 except that VH180 (basis weight: 180 g / m ² , plain weave) was used. Table 1 shows the results.

Example 8 As a reinforcing fiber, vinylon non-woven fabric V manufactured by Kuraray Co., Ltd.
A sample was prepared and subjected to a bending test in the same manner as in Example 1 except that M300 (basis weight 300 g / m ² ) was used. Table 1 shows the results.

Example 9 A sample was prepared and subjected to a bending test in the same manner as in Example 1 except that the adhesive Alonalpha (acrylic) manufactured by Toa Gosei Chemical Industry Co., Ltd. was used as the adhesive. Table 1 shows the results.

Comparative Example 1 A bending test was performed using the same molded sample as in Example 1 except that the reinforcing fibers were not bonded. Table 1 shows the results.

Comparative Example 2 At the time of reaction injection molding, reinforcing fibers made of the carbon fibers used in Example 1 were previously mounted in a mold, and then reaction injection molding was performed to obtain a molded product. A bending test was performed using a sample of the molded product. Table 1 shows the results.

[0047]

As described above, according to the present invention, since the reinforcing fiber is not filled in the inside of the molded product, the unevenness of the reinforcing fiber at the interface between the portion where the reinforcing fiber exists and the portion where the reinforcing fiber does not exist. A resin part having low physical properties due to an unfavorable distribution is not generated, and there is no possibility that a crack or distortion is generated in the molded product. Further, in the present invention, only the portion to be reinforced can be very easily reinforced, so that the amount of reinforcing fibers used can be reduced, and the cost of the molded product can be reduced. In addition, it was also confirmed that the strength of the molded article according to the present invention was extremely good as compared with a molded article in which reinforcing fibers were filled inside the molded article.

Further, in the production method of the present invention, the RIM molded product is obtained by providing a temperature difference to the mold to obtain a RIM molded product, so that the surface of the molded product in contact with the high temperature mold has a smooth skin. A layer is formed, and a micro-rough surface is formed on the surface of the molded product in contact with the mold having a low temperature. In the present invention,
By adhering the reinforcing fiber to the micro-rough surface side other than the skin layer via an adhesive, the adhesiveness of the reinforcing fiber to the polynorbornene-based resin molded product is improved.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code Agency reference number FI Technical display location C08L 45:00

Claims (2)

[Claims] 1. A polynorbornene-based resin molded article in which reinforcing fibers are adhered to at least a part of the surface of the polynorbornene-based resin molded article as a reinforcing material. 2. When a polynorbornene-based resin molded product is molded by reaction injection molding, a first mold and a second mold are used as molds, and the temperature of the second mold is adjusted to the first mold. The temperature of the molded product obtained by reaction injection molding is set to be higher than the temperature of the first mold set at a lower temperature, and at least a part of the surface of the molded product in contact with the first mold is set using an adhesive. ,
A method for producing a polynorbornene-based resin molded product, comprising bonding reinforcing fibers.