JP6110219B2 - Crosslinkable polycarbonate resin composition and molded product subjected to crosslinking treatment - Google Patents

Description

  The present invention relates to a crosslinkable polycarbonate resin composition and a molded article subjected to a crosslinking treatment. More specifically, the present invention relates to a molded article that has been subjected to a crosslinking treatment that has drastically improved heat resistance while maintaining the transparency that is characteristic of a polycarbonate resin, and a crosslinkable polycarbonate resin composition that provides the molded article.

  Polycarbonate resin is a thermoplastic resin excellent in transparency, impact resistance, heat resistance, and the like, and is widely used in fields such as electricity, electronics, ITE, machinery, and automobiles. However, its heat resistance is not always sufficient. For example, in applications such as solder mounting parts used in the vicinity of electronic circuits in the electric / electronic field, heat resistance much higher than that of ordinary polycarbonate resin is often required. There is a demand for a highly transparent polycarbonate resin that has excellent heat resistance and can be used.

  When the resin is polymerized for the purpose of improving the heat resistance of the polycarbonate resin, a method of improving the heat resistance by introducing a fluorene skeleton into the main chain (see Patent Document 1), a co-monomer using a compound having an allyl group. A method of blending a polyfunctional polymerizable monomer in a polymerized polycarbonate resin and crosslinking the composition by irradiation with radiation (see Patent Document 2) has been proposed. However, they are not commercialized even today because they are not sufficiently moldable as thermoplastic resins and have problems in terms of production efficiency and cost.

JP 2003-176325 A JP2007-314718

  The present invention relates to a crosslinkable polycarbonate resin composition capable of obtaining a molded article having dramatically improved heat resistance while maintaining the transparency inherent in the polycarbonate resin, and a molded article subjected to a crosslinking treatment comprising the same. The purpose is to provide.

  As a result of intensive studies in view of such problems, the present inventors have molded a composition in which a specific amount of a copolymer of a specific polybutylene terephthalate and an aliphatic polyester and a specific crosslinkable compound are blended in a polycarbonate resin. Surprisingly, it was found that heat resistance can be drastically improved while maintaining the excellent transparency inherent in polycarbonate resin by irradiating ionizing radiation to the molded product thus formed, and the present invention has been completed. It was.

That is, in the present invention, the polybutylene terephthalate and aliphatic polyester copolymer (B) 10 to 80 parts by weight and the crosslinkable compound (C) 0.05 to 30 parts by weight with respect to 100 parts by weight of the polycarbonate resin (A). a crosslinked polycarbonate resin composition Ru Tona, copolymer (B) is a copolymer of polybutylene terephthalate and polycaprolactone, crosslinkable compound (C) is a triallyl isocyanurate, crosslinking Crosslinkable polycarbonate resin composition, wherein the methylene chloride insoluble matter is 39 to 51% after the crosslinking treatment by irradiation with ionizing radiation is performed on the molded product of the conductive polycarbonate resin composition and the resin The molded article formed by molding the composition was subjected to a crosslinking treatment obtained by irradiating with ionizing radiation. It is to provide a molded article.

  The crosslinkable polycarbonate resin composition of the present invention can drastically improve the heat resistance while maintaining the excellent transparency inherent in the polycarbonate resin by irradiating the molded product obtained therefrom with ionizing radiation. It can be used suitably for applications that are transparent and require heat resistance of 260 ° C. or higher, for example, solder-mounted components used around electronic circuits.

  The polycarbonate resin (A) used in the present invention is obtained by a phosgene method in which various dihydroxydiaryl compounds and phosgene are reacted, or a transesterification method in which a dihydroxydiaryl compound and a carbonate such as diphenyl carbonate are reacted. A typical example of the polymer is a polycarbonate resin produced from 2,2-bis (4-hydroxyphenyl) propane (commonly referred to as bisphenol A).

  Examples of the dihydroxydiaryl compound include bisphenol 4-, bis (4-hydroxyphenyl) methane, 1,1-bis (4-hydroxyphenyl) ethane, 2,2-bis (4-hydroxyphenyl) butane, 2, 2-bis (4-hydroxyphenyl) octane, bis (4-hydroxyphenyl) phenylmethane, 2,2-bis (4-hydroxyphenyl-3-methylphenyl) propane, 1,1-bis (4-hydroxy-3) -Tert-butylphenyl) propane, 2,2-bis (4-hydroxy-3-bromophenyl) propane, 2,2-bis (4-hydroxy-3,5-dibromophenyl) propane, 2,2-bis ( Bis (hydroxyaryl) alkanes such as 4-hydroxy-3,5-dichlorophenyl) propane, 1,1- (4-hydroxyphenyl) cyclopentane, bis (hydroxyaryl) cycloalkanes such as 1,1-bis (4-hydroxyphenyl) cyclohexane, 4,4'-dihydroxydiphenyl ether, 4,4'-dihydroxy-3 Dihydroxy diaryl ethers such as 3,3'-dimethyldiphenyl ether, dihydroxy diaryl sulfides such as 4,4'-dihydroxydiphenyl sulfide, 4,4'-dihydroxydiphenyl sulfoxide, 4,4'-dihydroxy-3,3 ' Dihydroxy diaryl sulfoxides such as dimethyldiphenyl sulfoxide, dihydroxy diary such as 4,4'-dihydroxydiphenyl sulfone, 4,4'-dihydroxy-3,3'-dimethyldiphenyl sulfone Sulfone, and the like.

  These may be used alone or in combination of two or more. In addition to these, piperazine, dipiperidyl hydroquinone, resorcin, 4,4′-dihydroxydiphenyl, and the like may be used in combination.

  Furthermore, the above dihydroxyaryl compound and a trivalent or higher phenol compound as shown below may be used in combination. Trihydric or higher phenols include phloroglucin, 4,6-dimethyl-2,4,6-tri- (4-hydroxyphenyl) -heptene, 2,4,6-dimethyl-2,4,6-tri- (4 -Hydroxyphenyl) -heptane, 1,3,5-tri- (4-hydroxyphenyl) -benzol, 1,1,1-tri- (4-hydroxyphenyl) -ethane and 2,2-bis- [4 4- (4,4'-dihydroxydiphenyl) -cyclohexyl] -propane and the like.

  The viscosity average molecular weight of the polycarbonate resin (A) is not particularly limited, but is usually in the range of 10,000 to 100,000, more preferably 14,000 to 30,000, and even more preferably 16,000 to 26,000 in terms of moldability and strength. Moreover, when manufacturing this polycarbonate resin, a molecular weight modifier, a catalyst, etc. can be used as needed.

The copolymer (B) of polybutylene terephthalate and aliphatic polyester used in the present invention constitutes polybutylene terephthalate in 100 mol% of all monomer components constituting the copolymer (B). The monomer component is 50 mol% or more and 80 mol% or less, and the monomer component constituting the aliphatic polyester component is preferably 20 mol% or more and 50 mol% or less, and the polybutylene terephthalate and polycaprolactone Copolymers and the like can be exemplified, and commercially available products include perprene manufactured by Toyobo.
The melt index at 230 ° C. of the copolymer (B) of polybutylene terephthalate and aliphatic polyester is preferably 10-18, more preferably 13-18.

  The blending amount of the copolymer (B) of polybutylene terephthalate and aliphatic polyester is 10 to 80 parts by weight per 100 parts by weight of the polycarbonate resin (A). If the blending amount is less than 10 parts by weight, crosslinking does not occur sufficiently, so that heat resistance and transparency are inferior, and if it exceeds 80 parts by weight, granulation processing becomes difficult and it becomes impossible to obtain pellets of the resin composition. It is not preferable. A preferable compounding amount is 20 to 70 parts by weight, and more preferably 40 to 70 parts by weight.

  As the crosslinkable compound (C) used in the present invention, a crosslinkable compound capable of constraining the molecular chain of the polycarbonate resin by ionizing radiation is particularly suitable, and an allyl group, an acryl group, a methacryl group is included in the molecule. A polyfunctional compound having two or more unsaturated groups such as is preferably used.

  Examples of the polyfunctional compound having an allyl group include triallyl isocyanurate, trimethallyl isocyanurate, triallyl cyanurate, trimethallyl cyanurate, diallylamine, triallylamine, diacrylic chlorate, allyl acetate, allyl benzoate Allyl dipropyl isocyanurate, allyl octyl oxalate, allyl propyl phthalate, butyl allyl malate, diallyl adipate, diallyl carbonate, diallyl dimethyl ammonium chloride, diallyl fumarate, diallyl isophthalate, diallyl malonate, diallyl oxalate, diallyl phthalate , Diallylpropyl isocyanurate, diallyl sebacate, diallyl succinate, diallyl terephthalate, diallyl taterate , Dimethyl diallyl phthalate, ethyl allyl malate, methyl allyl fumarate, methyl meta-allyl maleate, diallyl monoglycidyl isocyanurate, monoallyl diglycidyl isocyanurate.

  In addition, acrylic or methacrylic polyfunctional compounds include 1,6-hexanediol di (meth) acrylate, 1,4-butanediol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, ethylene oxide modified Trimethylolpropane tri (meth) acrylate, propylene oxide modified trimethylolpropane tri (meth) acrylate, ethylene oxide modified bisphenol A di (meth) acrylate, diethylene glycol di (meth) acrylate, dipentaerythritol hexaacrylate, dipentaerythritol monohydroxypenta Acrylate, caprolactone-modified dipentaerythritol hexaacrylate, pentaerythritol tri (meth) acrylate, pentaerythritol Rutetora (meth) acrylate, polyethylene glycol di (meth) acrylate, tris (acryloyloxyethyl) isocyanurate, tris (methacryloxyethyl) isocyanurate.

  As the crosslinkable compound (C) used in the present invention, an allyl compound is preferably used because a high degree of crosslinking can be obtained at a relatively low concentration, and triallyl isocyanurate (TAIC) is particularly preferably used. .

  The compounding quantity of a crosslinkable compound (C) is 1-40 weight part per 100 weight part of polycarbonate resin (A). If the blending amount is less than 1 part by weight, crosslinking does not occur sufficiently, so that heat resistance and transparency are inferior, and if it exceeds 40 parts by weight, granulation processing becomes difficult and it becomes impossible to obtain pellets of the resin composition. Is not preferable. A preferable compounding amount is 5 to 30 parts by weight, and more preferably 10 to 20 parts by weight.

  Although there is no restriction | limiting in particular as a shaping | molding method of the crosslinkable polycarbonate resin composition of this invention, For example, injection molding, extrusion molding, blow molding, vacuum forming, compression molding, rotational molding, inflation molding etc. are mentioned. Electron beam, γ-ray, X-ray, β-ray, α-ray, etc. can be used as the ionizing radiation to irradiate the molded product molded into the required shape by the molding method. Electron beam irradiation or γ-ray irradiation with cobalt-60 can be preferably used. Of these, electron beam irradiation is particularly preferred from the standpoints of economy and crosslinking efficiency.

  The irradiation amount of the electron beam is preferably 50 to 1200 KGy. More preferably, it is 200-1000KGy.

A molded product obtained by subjecting a crosslinked polycarbonate resin composition to a crosslinking treatment can be measured for methylene chloride insoluble content to confirm the degree of crosslinking.
It is preferable that the methylene chloride insoluble content of the molded product subjected to the crosslinking treatment obtained by irradiating the molded product obtained by molding the crosslinkable polycarbonate resin composition of the present invention with ionizing radiation is 30% or more. . More preferably, it is 50% or more. If it is 30% or more, intermolecular crosslinking proceeds sufficiently and physical properties such as heat resistance are improved. If it is less than 30%, intermolecular cross-linking does not proceed sufficiently, and sufficient heat resistance may not be obtained.

The methylene chloride insoluble matter is measured as follows. 0.3 g of the molded product (test piece) after irradiation with ionizing radiation was carefully evaluated (initial weight of the sample), 100 ml of methylene chloride was added thereto, and the mixture was allowed to stand overnight at room temperature. Thereafter, the methylene chloride solution was filtered using a 300-mesh wire mesh having a known weight, and the methylene chloride-insoluble matter (gel content) on the wire mesh was air-dried for several hours. Furthermore, the gel was dried in an explosion-proof oven set at 50 ° C. for 1 hour, and the weight of the 300-mesh wire mesh gel (the weight of the gel after filtration and drying) was measured.
Methylene chloride insoluble matter (%): (gel weight after filtration and drying / initial weight of sample) × 100

  Since the molded article subjected to the crosslinking treatment of the present invention has an infinite number of three-dimensional network structures, it has heat resistance that does not deform even in a high temperature environment of 260 ° C. or higher.

Furthermore, the molded article subjected to the crosslinking treatment of the present invention also has excellent transparency inherent in the polycarbonate resin.

  Since the molded product subjected to the crosslinking treatment of the present invention has a crosslinked structure and has excellent transparency and heat resistance, it is used for automobile parts, electrical / electronic parts, medical parts, various sheets, It can be widely used for films. In particular, it can be suitably used for applications that are transparent and require heat resistance of 260 ° C. or higher, for example, solder-mounted components used around electronic circuits.

  There are no particular limitations on the blending method of the various blending components (A), (B), and (C) of the present invention, and these are mixed by an optional mixer such as a high-speed mixer, tumbler, ribbon blender, etc. It can be melt-kneaded with a screw or twin screw extruder. Moreover, there is no restriction | limiting in particular also about the mixing | blending order of these compounding components, collective mixing, and division | segmentation mixing.

  In addition, other known additives such as beeswax, pentaerythritol (PETS), glycerol monostearate (GMS), UV absorbers, antistatic agents, heat stabilizers, etc., may be added as needed. , Dyes and pigments, spreading agents (epoxidized soybean oil, liquid paraffin, etc.), reinforcing materials (glass fiber, carbon fiber, talc, mica, etc.), and other resins can be blended.

  The heat stabilizer is preferably a phosphorus type, and examples of such a phosphorus stabilizer include phosphite compounds, phosphonite compounds, and phosphate compounds. Examples of the phosphite compound include triphenyl phosphite, trisnonylphenyl phosphite, tris (2,4-di-tert-butylphenyl) phosphite, tridecyl phosphite, trioctyl phosphite, trioctadecyl phosphite, di Decyl monophenyl phosphite, dioctyl monophenyl phosphite, diisopropyl monophenyl phosphite, monobutyl diphenyl phosphite, monodecyl diphenyl phosphite, monooctyl diphenyl phosphite, bis (2,6-di-tert-butyl-4- Methylphenyl) pentaerythritol diphosphite, 2,2-methylenebis (4,6-di-tert-butylphenyl) octyl phosphite, bis (nonylphenyl) pentaerythritol diphosphite Sufaito, and bis (2,4-di -tert- butylphenyl) pentaerythritol diphosphite and the like.

  Examples of the phosphate compound include tributyl phosphate, trimethyl phosphate, tricresyl phosphate, triphenyl phosphate, trichlorophenyl phosphate, triethyl phosphate, diphenyl cresyl phosphate, diphenyl monoorxenyl phosphate, tributoxyethyl phosphate, dibutyl phosphate, dioctyl phosphate , Diisopropyl phosphate and the like.

Examples of phosphonite compounds include tetrakis (2,4-di-tert-butylphenyl) -4,4′-biphenyldiphosphonite and tetrakis (2,4-di-tert-butylphenyl) -4,3′-biphenyldi. Examples include phosphonite, tetrakis (2,4-di-tert-butylphenyl) -3,3′-biphenyldiphosphonite, bis (2,4-di-tert-butylphenyl) -4-biphenyldiphosphonite, and the like. It is done.
Among these, tris (2,4-di-tert-butylphenyl) phosphite, bis (2,6-di-tert-butyl-4-methylphenyl) pentaerythritol diphosphite trimethyl phosphate, tetrakis (2,4- Di-tert-butylphenyl) -4,4′-biphenyldiphosphonite can be preferably used.

  EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples. Parts and% are based on weight unless otherwise specified.

The compounding components used are as follows.
Polycarbonate resin:
Polycarbonate resin synthesized from bisphenol A and phosgene (Caliber 200-13, manufactured by Sumika Stylon Polycarbonate)
Viscosity average molecular weight: 21000, hereinafter abbreviated as PC)
Copolymer of polybutylene terephthalate and aliphatic polyester:
Perprene S2001 made by Toyobo
(Copolymer of polybutylene terephthalate and polycaprolactone)
(Melt index (230 ° C.): 16 hereinafter, abbreviated as PBPE)
Crosslinkable compound:
Nippon Kasei Co., Ltd. triallyl isocyanurate (hereinafter abbreviated as TAIC)

  The above-mentioned various blending components are collectively put into a high-speed mixer at the blending ratio shown in Table 1, and after dry mixing for 10 minutes, using a twin-screw extruder (KTX37 manufactured by Kobe Steel), the melting temperature is set to 230 ° C. And kneaded to obtain pellets of the crosslinkable polycarbonate resin composition.

(Test piece molding and electron beam irradiation)
The pellets of the various resin compositions obtained above were dried at 60 ° C. for 7 hours, respectively, and then set at a setting temperature of 230 ° C. and an injection pressure of 1600 kg / cm ² using an injection molding machine (Japan Steel Works J-100E-C5). A test piece (50 mm (width) x 50 mm (length) x 1 mm (thickness)) was prepared. The obtained test piece was irradiated with an electron beam (in air) at a dose of 800 KGy using a model EBC800-35 (acceleration voltage: 800 KV) manufactured by NHV Corporation.

(Evaluation of heat resistance and transparency of specimen after electron beam irradiation)
The test piece after electron beam irradiation obtained above was allowed to stand in a hot air circulation oven set at a temperature of 260 ° C. for 20 minutes, and the test piece was taken out of the oven, and then its appearance was visually confirmed. Regarding heat resistance, the test piece after the test did not melt and the edge remained completely was regarded as acceptable. Moreover, about transparency, the test piece after a test did not decompose | disassemble and foam, but the thing with good light transmittance was set as the pass.

(Measurement of methylene chloride insoluble matter in test pieces after electron beam irradiation)
0.3 g of the test piece after irradiation with the electron beam obtained above was carefully evaluated (initial weight of the sample), and 100 ml of methylene chloride was added thereto and allowed to stand overnight at room temperature. Thereafter, the methylene chloride solution was filtered using a 300-mesh wire mesh having a known weight, and the methylene chloride-insoluble matter (gel content) on the wire mesh was air-dried for several hours. Furthermore, the gel was dried in an explosion-proof oven set at 50 ° C. for 1 hour, and the weight of the 300-mesh wire mesh gel (the weight of the gel after filtration and drying) was measured.
Methylene chloride insoluble matter (%): (gel weight after filtration and drying / initial weight of sample) × 100

  When the obtained crosslinkable polycarbonate resin composition satisfies the constitutional requirements of the present invention (Examples 1 to 3), the cross-linked molded article has good heat resistance and transparency. Results are shown.

On the other hand, when the obtained crosslinkable polycarbonate resin composition did not satisfy the constituent requirements of the present invention, each case had some drawbacks.
Comparative Example 1 was inferior in heat resistance and transparency because the amount of TAIC was less than the range defined by the present invention.
Comparative Example 2 was inferior in heat resistance and transparency because the blending amount of the copolymer of polybutylene terephthalate and aliphatic polyester was less than the range defined by the present invention.
Comparative Example 3 was inferior in heat resistance and transparency because the sample was not irradiated with an electron beam.
In Comparative Example 4, since the blending amount of the copolymer of polybutylene terephthalate and aliphatic polyester was larger than the range defined by the present invention, granulation was difficult and pellets could not be produced.
In Comparative Example 5, since the TAIC content was larger than the range defined by the present invention, granulation was difficult and pellets could not be produced.

Claims (3)

Of the polycarbonate resin (A) 100 parts by weight of polybutylene terephthalate and a copolymer of the aliphatic polyester (B) 10 to 80 parts by weight of the crosslinkable compound (C) ing from 1 to 40 parts by weight crosslinking polycarbonate resin A composition comprising:
The copolymer (B) is a copolymer of polybutylene terephthalate and polycaprolactone,
The crosslinkable compound (C) is triallyl isocyanurate,
A crosslinkable polycarbonate resin composition having a methylene chloride insoluble content of 39 to 51% after the crosslinkable polycarbonate resin composition is subjected to crosslinking treatment by irradiation with ionizing radiation . . A molded article subjected to crosslinking treatment, obtained by irradiating a molded article obtained by molding the crosslinkable polycarbonate resin composition according to claim 1 with ionizing radiation. The molded article subjected to the crosslinking treatment according to claim 2 , wherein the ionizing radiation is an electron beam or a gamma ray.