JPH0360328B2 - - Google Patents

Description

[Detailed description of the invention]

[Field of the Invention] The present invention relates to a molded product of polyethylene terephthalate resin that is not subjected to cooling stretching treatment at a relatively low temperature, e.g.
This invention relates to an ultraviolet curable resin composition that has improved the phenomenon of embrittlement caused by heating at 150°C for several hours. [Conventional technology] Polyethylene terephthalate resin (hereinafter referred to as PET)
) are used in large quantities mainly in the form of fibers, films, etc. for electrical insulation and textile industries. All of these materials have their crystal structures oriented and regulated by cooling stretching treatment and heat setting treatment, making them strong and flexible, and at temperatures around 200°C,
It is well known that the crystal structure does not change and flexibility is maintained. However, if this PET is integrally molded with a constituent material such as metal, subsequent cooling and stretching treatment is impossible, and as a result, PET is severely thermally embrittled and cannot be put to practical use. In view of these points, the inventors of the present invention have developed a method of integrally molding this useful PET, which has been used for many years, with other constituent materials such as metal, and that it does not become thermally embrittled even without a subsequent cooling and stretching process. We succeeded in obtaining a PET-based resin composition. PET molded products do not need to be subjected to cooling stretching treatment.
Although it is highly flexible by adjusting the cooling rate, etc., the crystal structure changes and becomes brittle within a few hours even at 150°C, which is relatively low compared to the processing temperature. Therefore, in order to prevent changes in the crystal structure, we considered mixing various functional resins and performing crosslinking with various crosslinking agents, but the crosslinking progressed partially or completely depending on the PET molding temperature. The molded product itself could not be stably obtained due to gelation. However, the present inventors have found that only compositions containing a certain type of functional resin and a Lewis acid-releasing photopolymerizer capable of initiating polymerization of the functional resin are stable to heat, and are stable at a temperature of PET extrusion processing. However, they have finally discovered that it not only hardly decomposes and can be freely molded, but also retains its UV polymerization function after the process. Thus, by mixing an epoxy resin with a PET-based resin and adding a Lewis acid-releasing photopolymerization agent, it is possible to create an excellent image that can be freely molded and does not cause thermal embrittlement with only subsequent ultraviolet treatment. We succeeded in obtaining a novel resin composition. [Summary of the Invention] The present invention provides a method for combining a resin whose main component is polyethylene terephthalate resin and one or more cationically polymerizable compounds whose main component is an epoxy resin having two or more oxirane rings in one molecule into the polyethylene terephthalate resin. It is characterized by containing 50% by weight or less based on the resin, and further containing 0.1 to 10% by weight based on the cationic polymerizable compound of a photopolymerization initiator for the cationic polymerizable compound that releases the Lewis acid catalyst by irradiation with ultraviolet rays. It is an ultraviolet curable resin composition. The PET used in the present invention is preferably commercially available, such as a film or fiber grade, or a bottle grade with an increased degree of polymerization using solid phase polymerization, but if the softening point is 170°C or higher, it may contain an isophthalic acid component. It can also be used. In addition, polybutylene terephthalate resin, which is a resin of the same type, and polyarylate resin, which is known to be compatible with PET according to Japanese Patent Application No. 57-198113, and also compatible with PET, according to Japanese Patent Application No. 57-138706. polycarbonate resin known to have
It may be substituted with 30% by weight or less of PET. The cationic polymerizable compound used in the present invention is
A cationic polymerizable compound whose main component is an epoxy resin having two or more oxirane rings in one molecule
The epoxy resin is preferably a bisphenol A type epoxy resin, a novolak type epoxy resin, an alicyclic epoxy resin, or the like. Such bisphenol A type epoxy resins include, for example, Epicote 828, Epicote 834, Epicote 836, Epicote 1001, Epicote 1004,
Epicote 1007 (manufactured by Ciel Chemical Co., Ltd., product name), DER331, DER332, DER661, DER664,
DER667 (hereinafter manufactured by Dow Chemical Company, product name), Araldite 260, Araldite 280, Araldite
6071, Araldite 6084, Araldite 6097 (trade names, manufactured by Ciba Geigy), etc., and these may be used alone or in combination. Further, as the novolak type epoxy resin,
For example, Epicote 152, Epicote 154 (and above,
Manufactured by Ciel Chemical Co., Ltd., trade name), Araldite
EPN1138, Araldite EPN1139, Araldite ECN1235, Araldite ECN1273, Araldite ECN1280, Araldite ECN1299 (manufactured by Ciba Geigy, product name), DEN431, DEN438
(all manufactured by Dow Chemical Company, trade name), etc., and these can be used alone or in combination. Further, examples of the alicyclic epoxy resin include Araldite CY175, Araldite CY177,
Araldite CY179, Araldite CY184, Araldite CY192 (manufactured by Ciba Geigy, product name), ERL-4221, ERL-4299, ERL-4234 (manufactured by Union Carbide, product name), etc. Or used in combination. Other butadiene-based epoxy resins can also be used, and mixtures of the various epoxy resins mentioned above can also be used. A monofunctional epoxy diluent may be used in the cationic polymerizable compound within a range that does not deteriorate the curing properties. Examples of such monofunctional epoxy diluents include phenyl glycidyl ether and t-butyl glycidyl ether. Furthermore, it is also possible to use a cationically polymerizable vinyl compound mixed with the epoxy resin,
Examples of such cationically polymerizable vinyl compounds include styrene, allylbenzene, triallyl isocyanate, triallylcyanate, vinyl ether, N-vinylcarbazole, and N-vinylpyrrolidone. The photopolymerization initiator used in the present invention, which releases a Lewis acid catalyst that initiates polymerization of a cationically polymerizable compound by ultraviolet irradiation, includes aromatic diazonium salts, aromatic halonium salts, group a or group a element Examples include photosensitive aromatic onium salts. Such an aromatic diazonium salt has the general formula (): (In the formula, R ₁ and R ₂ are hydrogen atoms, alkyl groups, or alkoxy groups, R ₃ is a hydrogen atom, an aromatic group, or an aromatic group connected by an amide group or a sulfur atom, M is a metal or semimetal, and Q represents a halogen atom, a=(b-c) holds, and c is an integer from 2 to 7 and equal to the valence of M, and b is c
(representing an integer greater than or equal to 8), for example,

【formula】

【formula】

【formula】

【formula】

【formula】

etc. Further, the aromatic halonium salt has the general formula (): [(R ₄ ) _d (R ₅ ) _e X] ⁺ _f [MQ _g ] ^-(gh) () (wherein, R ₄ is a monovalent aromatic organic group, R ₅ is a divalent aromatic organic group, X is a halogen atom such as I, Br, Cl, M is a metal or metalloid and Q is a halogen atom, d is 0 or 2, e is 0
or 1, and (d+e) is equal to 2 or the valence of etc. Further, as a group a element or a photosensitive aromatic onium salt of a group a element, the general formula (): [(R ₆ ) ⁱ _i (R ₇ ) _j (R ₈ ) _k Y] ⁺ _l [MQ _n ] ^-(mn) () (wherein R ₆ is a monovalent aromatic organic group, R ₇ is a monovalent aliphatic organic group selected from the group consisting of an alkyl group, a cycloalkyl group, and a substituted alkyl group, R ₈ is a heterocyclic group selected from an aliphatic organic group and an aromatic organic group or a polyvalent organic group constituting a condensed ring structure, Y is a group a element of S, Se, Te or N,
Group A element selected from P, As, Sb and Bi; M is a metal or metalloid; Q is a halogen atom; i is an integer of 0 to 4; j is an integer of 0 to 2; k is an integer of 0 to 2; is an integer of 2, and (i+j+
k) is equal to the valence of Y, equal to 3 when Y is a group a element, equal to 4 when Y is a group a element, i=(m-n) holds, and n is 2 to A compound represented by an integer of 7 equal to the valence of M, where m represents an integer greater than n and less than or equal to 8), and as an onium salt of a group a element, for example,

【formula】

【formula】

Examples of onium salts of group a elements include

【formula】

【formula】

etc. The amount of the Lewis acid free photopolymerization initiator added to the cationic polymerizable compound is 0.1 to 10% by weight, preferably 1 to 5% by weight of the cationic polymerizable compound, and if it is less than 0.1% by weight, UV rays The crosslinking reaction rate tends to be slow and the treatment time tends to be too long, and if the amount exceeds 10% by weight, the catalyst cost is high, which increases the price of the resin composition. The composition of the present invention can be applied to constituent materials that are integrated with metal etc. by molding processes such as injection, extrusion, and pressing, i.e., corrosion-resistant metal materials, substrates for electronic circuits,
Can be used for insulated wires, etc. Further, for the ultraviolet cross-linking treatment after the molding process, irradiation with a light source such as a low-pressure mercury lamp, high-pressure mercury lamp, xenon lamp, or carbon arc lamp, or electron beam irradiation is used. [Examples of the Invention] Next, the composition of the present invention will be described in detail based on Examples and Comparative Examples, but the present invention is not limited to the following Examples. Example 1 70 parts by weight of PET pellets were freeze-pulverized into bulk form (clumps), and 30 parts by weight of Epicote 828 (bisphenol A type epoxy resin) and 0.5 parts by weight of triphenylsulfonium hexafluoroantimonate were added.
The parts by weight were mixed, kneaded in a kneader at 280°C for 10 minutes, then cooled and pelletized, and the pellets were maintained at 250°C in the barrel and 280°C in the head.L/D=
The composition was put into the hopper of a No. 28 extruder, and the composition was placed on a copper strip of 0.25 mm thick and 50 mm thick using a T-type die to a thickness of 50 μm.
The copper strip was coated by extrusion at M to obtain a single-sided integrally molded copper strip. This molded product has a bending property of 180° with a diameter of 3 mm, a steel ball with a diameter of 1.6 mm is placed on the coated surface, a load of 1 kg is applied thereto, 100 V AC is applied between the steel ball and the copper strip, and the temperature is constant. Table 1 shows the softening points measured by increasing the temperature in a bath at a rate of about 2° C./min. Example 2 Pellets obtained in the same manner as in Example 1 were charged into the hopper of an extruder with L/D = 28, which was maintained at a barrel temperature of 250°C and a head temperature of 280°C.
It was extruded onto a 1.0 mm diameter copper wire to a thickness of 40 μm to obtain an insulated wire. Table 1 shows the measurement results of winding flexibility and softening point according to JISC3003. Example 3 80 parts by weight of PET pellets were frozen and crushed into a bulk form, and 20 parts by weight of Epicote 152 (novolac type epoxy resin) and 0.3 parts by weight of diphenyliodonium hexafluorophosphate were mixed,
Kneaded in a kneader at 280℃ for 10 minutes, then cooled.
The pellets were made into pellets, and the pellets were put into the hopper of an extruder with L/D = 28, which maintained the barrel at 260℃ and the crosshead at 280℃.
An insulated wire was obtained by extrusion. Table 1 shows the measurement results of winding flexibility and softening point according to JIS C3003. Example 4 70 parts by weight of PET pellets were dissolved in 397 parts by weight of p-chlorophenol, and 20 parts by weight of Epicoat was dissolved in 397 parts by weight of p-chlorophenol.
828, and 10 parts by weight of Epicote 152 are dissolved and dispersed, and then triphenylsulfonium hexafluoroantimonate propylene carbonate is dissolved and dispersed.
1.0 part by weight of the 50% solution was further dissolved to obtain a transparent homogeneous solution. The solvent was sufficiently removed from this solution at 100℃ under reduced pressure, and the solution was melted at 280℃ in a melting tank with a structure that allows it to be discharged from the lower hole under nitrogen gas pressure. It was connected to a crosshead of the same mechanism and coated on a 1.0 mm diameter copper wire to a thickness of 40 μm using a die and a nipple. At this time, the crosshead temperature was 290°C. Note that this coating method is generally called a hot melt coating method. Table 1 shows the results of measuring the winding flexibility and softening point of the obtained insulated wire according to JIS C3003. Comparative example 1 PET pellets were heated at 250°C in the barrel and at 290°C in the head.
It was put into the hopper of an extruder with L/D = 28 held at Ta. The bending properties and softening points obtained by the same method as in Example 1 are shown in Table 1. Comparative example 2 PET pellets were heated at 250°C in the barrel and 290°C in the head.
1.0
It was extruded onto mm copper wire to a thickness of 40 μm to obtain an insulated wire. Table 1 shows the measurement results of winding flexibility and softening point according to JIS C3003. Comparative Example 3 80 parts by weight of PET pellets were dissolved in 453 parts by weight of p-chlorophenol, and glycidyl ether of bisphenol A (viscosity 120-150 poise/25°C,
20 parts by weight of Gramdic FC-0511 (manufactured by Dainippon Ink & Chemicals Co., Ltd., trade name) was dissolved and dispersed in diacrylate of epoxy equivalent (184 to 194), and then 2,2-diethoxyacetate was added as a photopolymerization initiator. 0.2 parts by weight of phenone was additionally dissolved to obtain a transparent homogeneous solution. The solvent was removed from this solution using the same method and conditions as in Example 4, and an attempt was made to coat a copper wire with a diameter of 1.0 mm using the so-called hot melt coating method. but,
The molten composition gelled and no insulated wire was obtained. [Effects of the Invention] As is clear from the experimental results shown in Table 1, the molded products made only of PET shown in Comparative Examples 1 and 2 suffer from severe thermal embrittlement and cannot be put to practical use. Furthermore, as shown in Comparative Example 3, when an acrylate crosslinking agent is used, gelation occurs during the molding process, and a molded product cannot be obtained. In contrast, in Examples 1 to 4 of the present invention, gelation did not occur during the molding process, and the molded products obtained had a low softening point as the epoxy resin acted as a plasticizer when not irradiated with ultraviolet rays. The phenomenon of thermal embrittlement is also observed, but by UV irradiation treatment, the softening point is also improved, and it can be seen that the embrittlement caused by thermal deterioration at 200°C is almost completely improved. In addition, molded products using the composition according to the present invention that have been subjected to ultraviolet irradiation treatment have excellent mechanical strength, electrical insulation properties, solvent resistance, etc., and are therefore extremely useful compositions. confirmed.

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【table】

Claims (1)

[Scope of Claims] 1. A resin whose main component is a polyethylene terephthalate resin, and one or more cationic polymerizable compounds whose main component is an epoxy resin having two or more oxirane rings in one molecule are added to the polyethylene terephthalate resin. Ultraviolet curing characterized by containing 0.1 to 10 weight percent of the cationic polymerizable compound photopolymerization initiator, which releases the Lewis acid catalyst by ultraviolet irradiation. mold resin composition. 2. The photopolymerization initiator is one or a mixture of two or more selected from the group consisting of aromatic diazonium salts, aromatic halonium salts, and group a elements or photosensitive aromatic onium salts of group a elements. An ultraviolet curable resin composition according to claim 1. 3. The ultraviolet curable resin composition according to claim 1, wherein 30 weight percent or less of the polyethylene terephthalate resin is replaced with a polybutylene terephthalate resin, a polyarylate resin, or a polycarbonate resin.