Flame-retardant polycarbonate resin composition and molded article obtained by molding same

Abstract

The present invention provides: a flame-retardant polycarbonate resin composition which has high safety for human bodies and is excellent in flame retardancy, thermal stability, chemical resistance, and impact resistance; and a molded article obtained by molding same. This flame-retardant polycarbonate resin composition contains, with respect to a total of 100 parts by weight of (A) 40-70 parts by weight of a polycarbonate resin (component A) and (B) 60-30 parts by weight of a polybutylene terephthalate resin (component B): (C) 15-30 parts by weight of a brominated polycarbonate-based flame retardant (component C); (D) 4-10 parts by weight of a phosphazene (component D) containing 98.5 mol% or more of a phosphazene cyclic trimer; (E) 5-15 parts by weight of an impact modifier (component E); (F) 0.01-0.5 parts by weight of a transesterification reaction inhibitor (component F); and (G) 0.1-1 parts by weight of a drip inhibitor (component G).

Description

Flame Retardant Polycarbonate Resin Composition and Molded Article Formed Therefrom

[0001] The present invention relates to a flame retardant polycarbonate resin composition having high safety to the human body and excellent flame retardancy, thermal stability, chemical resistance and impact resistance, and a molded article formed therefrom.

[0002] Polycarbonate resins are widely used industrially because they have excellent mechanical properties and thermal properties. However, since polycarbonate resins are amorphous resins, they have the drawback of being inferior in chemical resistance. In order to improve the chemical resistance of polycarbonate resins, many polymer alloys with other thermoplastic resins have been developed. Among them, polymer alloys with polyester resins represented by polyethylene terephthalate resins and polybutylene terephthalate resins are widely used in the automotive field and the electric and electronic equipment field. In particular, for medical device exterior material applications, in addition to high chemical resistance to disinfectants, there are requirements for flame retardancy and impact resistance, and various flame retardant resin compositions have been proposed.

[0003] For example, a method of using a halogen-based flame retardant and an antimony compound in combination with a polycarbonate resin and a polyester resin (Patent Document 1) has been disclosed, but there is a problem that the thermal stability during molding processing is significantly reduced due to the catalytic action of the antimony compound. In recent years, there are concerns about the health risks of antimony compounds to the human body, and a flame retardant polycarbonate resin composition containing no antimony compound is desired. Therefore, a flame retardant resin composition containing no antimony compound has been disclosed. For example, methods of using a boron compound, red phosphorus, a phosphate ester, and a phosphorus-based flame retardant having a specific structure as a flame retardant (Patent Documents 2 to 5) have been disclosed, but at present, none of them have been able to provide a flame retardant polycarbonate resin composition having all of flame retardancy, thermal stability, chemical resistance and impact resistance.

[0004] JP-A-2015-081327, JP-A-2000-001610, JP-A-2000-136297, JP-A-08-012864, JP-A-2019-135286

[0005] In view of the above, an object of the present invention is to provide a flame-retardant polycarbonate resin composition having high safety to the human body and excellent flame retardancy, heat stability, chemical resistance and impact resistance, and a molded article formed therefrom.

[0006] As a result of intensive studies to solve the above problems, the present inventors have found that by adding a polybutylene terephthalate resin, a brominated polycarbonate-based flame retardant, a phosphazene containing 98.5 mol% or more of a phosphazene cyclic trimer, an impact modifier, a transesterification inhibitor and a drip inhibitor to a polycarbonate resin, a flame-retardant polycarbonate resin composition excellent in flame retardancy, heat stability, chemical resistance and impact resistance can be obtained, and the present invention has been completed.

[0007] According to the present invention, the above problems are achieved by the following items 1 to 10. 1. Based on a total of 100 parts by weight of (A) 40 to 70 parts by weight of a polycarbonate resin (component A) and (B) 60 to 30 parts by weight of a polybutylene terephthalate resin (component B), (C) 15 to 30 parts by weight of a brominated polycarbonate-based flame retardant (component C), (D) 4 to 10 parts by weight of a phosphazene containing 98.5 mol% or more of a phosphazene cyclic trimer (component D), (E) 5 to 15 parts by weight of an impact modifier (component E), (F) 0.01 to 0.5 parts by weight of a transesterification inhibitor (component F), and (G) 0.1 to 1 part by weight of a drip inhibitor (component G). A flame-retardant polycarbonate resin composition. 2. The flame-retardant polycarbonate resin composition according to item 1 above, wherein component A is a polycarbonate-polyorganosiloxane copolymer resin. 3. The flame-retardant polycarbonate resin composition according to item 1 or 2 above, wherein component B is a polybutylene terephthalate resin having an intrinsic viscosity of 0.4 to 1.5. 4. Component C is represented by the following formula (5) (In formula (5), X is a bromine atom, R is an alkylene group having 1 to 4 carbon atoms, an alkylidene group having 1 to 4 carbon atoms or -SO , <00000, —. ) A brominated polycarbonate compound having a structural unit represented by the formula, and the flame-retardant polycarbonate resin composition according to any one of items 1 to 3 above. 5. The phosphazene cyclic trimer in component D is represented by the following formula (8) 1. A flame-retardant polycarbonate resin composition according to any one of paragraphs 1 to 4, wherein the compound is represented by formula (8), where k = 1. 6. A flame-retardant polycarbonate resin composition according to any one of paragraphs 1 to 5, wherein component E is a graft polymer obtained by graft polymerizing at least one compound containing a (meth)acrylic acid ester compound on one rubber selected from the group consisting of butadiene rubber, acrylic rubber, and silicone-acrylic composite rubber. 7. A flame-retardant polycarbonate resin composition according to any one of paragraphs 1 to 6, wherein component F is at least one compound selected from the group consisting of phosphite compounds and phosphate compounds. 8. A flame-retardant polycarbonate resin composition according to any one of paragraphs 1 to 7, wherein component G is a fluorine-containing polymer having fibril-forming ability. 9. A molded article obtained by molding the flame-retardant polycarbonate resin composition according to any one of paragraphs 1 to 8. 10. A molded article according to paragraph 9, which is an exterior material for medical devices.

[0008] The flame-retardant polycarbonate resin composition of the present invention is highly safe for the human body and achieves a high level of balance between flame retardancy, thermal stability, chemical resistance, and impact resistance. Therefore, it is not limited to medical device applications such as exterior materials for medical devices, but is also widely useful in various fields such as housing equipment, building materials, daily living materials, infrastructure equipment, automobiles, OA / EE applications, outdoor equipment applications, and many other fields. Accordingly, the industrial effects achieved by the present invention are extremely significant.

[0009] The details of the present invention will be described below. (Component A: Polycarbonate resin) The polycarbonate resin used in the present invention is obtained by reacting a divalent phenol with a carbonate precursor. Examples of reaction methods include interfacial polymerization, molten transesterification, solid-phase transesterification of carbonate prepolymers, and ring-opening polymerization of cyclic carbonate compounds.

[0010] Typical examples of divalent phenols used here include hydroquinone, resorcinol, 4,4'-biphenol, 1,1-bis(4-hydroxyphenyl)ethane, 2,2-bis(4-hydroxyphenyl)propane (commonly known as bisphenol A), 2,2-bis(4-hydroxy-3-methylphenyl)propane, 2,2-bis(4-hydroxyphenyl)butane, 1,1-bis(4-hydroxyphenyl)-1-phenylethane, 1,1-bis(4-hydroxyphenyl)cyclohexane, 1,1-bis(4-hydroxyphenyl)-3,3,5-trimethylcyclohexane, 2,2-bis(4-hydroxyphenyl)pentane, and 4,4'-(p-phenyl Examples include bis(4-hydroxyphenyl)diphenol, 4,4'-(m-phenylenediisopropylidene)diphenol, 1,1-bis(4-hydroxyphenyl)-4-isopropylcyclohexane, bis(4-hydroxyphenyl)oxide, bis(4-hydroxyphenyl)sulfide, bis(4-hydroxyphenyl)sulfoxide, bis(4-hydroxyphenyl)sulfone, bis(4-hydroxyphenyl)ketone, bis(4-hydroxyphenyl)ester, bis(4-hydroxy-3-methylphenyl)sulfide, 9,9-bis(4-hydroxyphenyl)fluorene, and 9,9-bis(4-hydroxy-3-methylphenyl)fluorene. Preferred divalent phenols are bis(4-hydroxyphenyl)alkanes, among which bisphenol A is particularly preferred and widely used in terms of impact resistance.

[0011] In this invention, in addition to bisphenol A-based polycarbonates, which are general-purpose polycarbonates, it is also possible to use special polycarbonates manufactured using other divalent phenols as component A.

[0012] For example, polycarbonates (homopolymers or copolymers) using 4,4'-(m-phenylenediisopropylidene)diphenol (sometimes abbreviated as "BPM"), 1,1-bis(4-hydroxyphenyl)cyclohexane, 1,1-bis(4-hydroxyphenyl)-3,3,5-trimethylcyclohexane (sometimes abbreviated as "Bis-TMC"), 9,9-bis(4-hydroxyphenyl)fluorene, and 9,9-bis(4-hydroxy-3-methylphenyl)fluorene (sometimes abbreviated as "BCF") as some or all of the divalent phenol components are suitable for applications where dimensional changes due to water absorption and morphological stability are particularly demanding. It is preferable to use these divalent phenols other than BPA in an amount of 5 mol% or more, particularly 10 mol% or more, of the total divalent phenol components constituting the polycarbonate.

[0013] In particular, when high rigidity and better hydrolysis resistance are required, it is especially preferable that component A constituting the resin composition be one of the following copolymer polycarbonates (1) to (3): (1) A copolymer polycarbonate in which, of 100 mol% of the divalent phenol component constituting the polycarbonate, BPM is 20 to 80 mol% (more preferably 40 to 75 mol%, even more preferably 45 to 65 mol%) and BCF is 20 to 80 mol% (more preferably 25 to 60 mol%, even more preferably 35 to 55 mol%). (2) A copolymer polycarbonate in which, of 100 mol% of the divalent phenol component constituting the polycarbonate, BPA is 10 to 95 mol% (more preferably 50 to 90 mol%, even more preferably 60 to 85 mol%) and BCF is 5 to 90 mol% (more preferably 10 to 50 mol%, even more preferably 15 to 40 mol%). (3) A copolymer polycarbonate in which, of 100 mol% of the divalent phenol component constituting the polycarbonate, BPM is 20 to 80 mol% (more preferably 40 to 75 mol%, even more preferably 45 to 65 mol%) and Bis-TMC is 20 to 80 mol% (more preferably 25 to 60 mol%, even more preferably 35 to 55 mol%).

[0014] These special polycarbonates may be used individually, or two or more may be mixed as appropriate. They can also be mixed with commonly used bisphenol A type polycarbonates.

[0015] The manufacturing methods and properties of these special polycarbonates are described in detail in, for example, Japanese Patent Publication No. 6-172508, Japanese Patent Publication No. 8-27370, Japanese Patent Publication No. 2001-55435, and Japanese Patent Publication No. 2002-117580.

[0016] Furthermore, among the various polycarbonates mentioned above, those whose copolymer composition and other properties have been adjusted to bring the water absorption rate and Tg (glass transition temperature) within the following ranges are particularly suitable for fields requiring morphological stability because they exhibit excellent hydrolysis resistance of the polymer itself and significantly superior low warpage after molding. (i) Polycarbonates having a water absorption rate of 0.05 to 0.15%, preferably 0.06 to 0.13%, and a Tg of 120 to 180°C, or (ii) Polycarbonates having a Tg of 160 to 250°C, preferably 170 to 230°C, and a water absorption rate of 0.10 to 0.30%, preferably 0.13 to 0.30%, more preferably 0.14 to 0.27%.

[0017] Here, the water absorption rate of polycarbonate was measured using a disc-shaped test piece with a diameter of 45 mm and a thickness of 3.0 mm, after immersion in water at 23°C for 24 hours in accordance with ISO 62-1980. The glass transition temperature (Tg) was determined by differential scanning calorimeter (DSC) measurement in accordance with JIS K7121.

[0018] Carbonyl halides, diester carbonates, or haloformates are used as carbonate precursors, specifically including phosgene, diphenyl carbonate, or dihaloformates of divalent phenols.

[0019] In producing the aromatic polycarbonate resin by interfacial polymerization of the divalent phenol and the carbonate precursor, a catalyst, an end-terminating agent, an antioxidant to prevent oxidation of the divalent phenol, etc., may be used as needed. The aromatic polycarbonate resin of the present invention includes branched polycarbonate resin copolymerized with a trifunctional or polyfunctional aromatic compound, polyester carbonate resin copolymerized with an aromatic or aliphatic (including alicyclic) bifunctional carboxylic acid, copolymerized polycarbonate resin copolymerized with a bifunctional alcohol (including alicyclic), and polyester carbonate resin copolymerized with both such bifunctional carboxylic acid and bifunctional alcohol. Furthermore, a mixture of two or more of the obtained aromatic polycarbonate resins may also be used.

[0020] Branched polycarbonate resins can impart properties such as drip prevention to the resin composition of the present invention. Examples of trifunctional or polyfunctional aromatic compounds used in such branched polycarbonate resins include phloroglucin, phloroglucides, or 4,6-dimethyl-2,4,6-tris(4-hydroxyphenyl)heptene-2,2,4,6-trimethyl-2,4,6-tris(4-hydroxyphenyl)heptane, 1,3,5-tris(4-hydroxyphenyl)benzene, 1,1,1-tris(4-hydroxyphenyl)ethane, 1,1,1-tris(3,5-dimethyl-4-hydroxyphenyl)ethane, 2,6-bis(2-hydroxy-5-methylbenzyl)-4-methylphenol, and 4-{4-[1,1-bis(4- Examples include trisphenols such as hydroxyphenyl)ethyl]benzene}-α,α-dimethylbenzylphenol, tetra(4-hydroxyphenyl)methane, bis(2,4-dihydroxyphenyl)ketone, 1,4-bis(4,4-dihydroxytriphenylmethyl)benzene, or trimellitic acid, pyromellitic acid, benzophenonetetracarboxylic acid and their acid chlorides, among which 1,1,1-tris(4-hydroxyphenyl)ethane and 1,1,1-tris(3,5-dimethyl-4-hydroxyphenyl)ethane are preferred, and 1,1,1-tris(4-hydroxyphenyl)ethane is particularly preferred.

[0021] In branched polycarbonates, the constituent units derived from polyfunctional aromatic compounds are preferably 0.01 to 1 mol%, more preferably 0.05 to 0.9 mol%, and even more preferably 0.05 to 0.8 mol%, of the total 100 mol% of constituent units derived from divalent phenols and constituent units derived from such polyfunctional aromatic compounds.

[0022] Furthermore, especially in the case of the melt transesterification method, branched structural units may be produced as a side reaction. However, the amount of such branched structural units is preferably 0.001 to 1 mol%, more preferably 0.005 to 0.9 mol%, and even more preferably 0.01 to 0.8 mol%, of the total 100 mol% of the constituent units derived from the divalent phenol. １ It can be calculated by H-NMR measurement.

[0023] Among aliphatic difunctional carboxylic acids, α,ω-dicarboxylic acids are preferred. Examples of aliphatic difunctional carboxylic acids include linear saturated aliphatic dicarboxylic acids such as sebacic acid (decanediic acid), dodecanediic acid, tetradecanediic acid, octadecanediic acid, and eicosanedioic acid, as well as alicyclic dicarboxylic acids such as cyclohexanedicarboxylic acid. As for difunctional alcohols, alicyclic diols are more preferred, and examples include cyclohexanedimethanol, cyclohexanediol, and tricyclodecanedimethanol.

[0024] The reaction methods used in the present invention for producing polycarbonate resin, such as interfacial polymerization, molten transesterification, solid-phase transesterification of carbonate prepolymers, and ring-opening polymerization of cyclic carbonate compounds, are well-known methods described in various literatures and patent publications.

[0025] In producing the flame-retardant polycarbonate resin composition of the present invention, the viscosity-average molecular weight (M) of the polycarbonate resin is not particularly limited, but is preferably 1.8 × 10 ４ ~4.0 x 10 ４ More preferably, 2.0 × 10 ４ ~3.5 x 10 ４ More preferably 2.2 × 10４ ~3.0×10 ４ is. When the polycarbonate resin has a viscosity average molecular weight of less than 1.8×10 ４ , good mechanical properties may not be obtained. On the other hand, a resin composition obtained from a polycarbonate resin having a viscosity average molecular weight exceeding 4.0×10 ４ is inferior in versatility in terms of inferior fluidity during injection molding.

[0026] Incidentally, the polycarbonate resin may be obtained by mixing those having a viscosity average molecular weight outside the above range. In particular, a polycarbonate resin having a viscosity average molecular weight exceeding the above range (5×10 ４ ) improves the entropy elasticity of the resin. As a result, good molding processability is exhibited in gas-assisted molding and foam molding that may be used when molding a reinforced resin material into a structural member. Such improvement in molding processability is even better than that of the branched polycarbonate. As a more preferred embodiment, component A is a polycarbonate resin A-1-1-1 component having a viscosity average molecular weight of 7×10 ４ ~3×10 ５ , and an aromatic polycarbonate resin (A-1-1-2 component) having a viscosity average molecular weight of 1×10 ４ ~3×10 ４ , and a polycarbonate resin (A-1-1 component) having a viscosity average molecular weight of 1.6×10 ４ ~3.5×10 ４ (hereinafter sometimes referred to as "polycarbonate resin containing high molecular weight component") can also be used.

[0027] In such a polycarbonate resin (A-1-1 component) containing a high molecular weight component, the molecular weight of the A-1-1-1 component is 7×10 ４ ~2×10 ５ is preferable, more preferably 8×10 ４ ~2×10 ５ , further preferably 1×10 ５ ~2×10 ５ , particularly preferably 1×10 ５ ~1.6×10 ５ is. Also, the molecular weight of the A-1-1-2 component is 1×10 ４ ~2.5×10４ Preferably, 1.1 × 10 ４ ~2.4 x 10 ４ More preferably 1.2 × 10 ４ ~2.4 x 10 ４ Particularly preferred is 1.2 × 10 ４ ~2.3 x 10 ４ That is the case.

[0028] A polycarbonate resin containing high molecular weight components (component A-1-1) can be obtained by mixing component A-1-1-1 and component A-1-1-2 in various proportions and adjusting them to satisfy a predetermined molecular weight range. Preferably, component A-1-1-1 is present in an amount of 2 to 40% by weight of 100% by weight of component A-1-1, more preferably 3 to 30% by weight of component A-1-1-1, even more preferably 4 to 20% by weight of component A-1-1-1, and particularly preferably 5 to 20% by weight of component A-1-1-1.

[0029] Furthermore, methods for preparing component A-1-1 include (1) a method of independently polymerizing component A-1-1-1 and component A-1-1-2 and mixing them; (2) a method of producing an aromatic polycarbonate resin that exhibits multiple polymer peaks in a molecular weight distribution chart by GPC method within the same system, as exemplified by the method shown in Japanese Patent Application Publication No. 5-306336, and producing such an aromatic polycarbonate resin to satisfy the conditions for component A-1-1 of the present invention; and (3) a method of mixing the aromatic polycarbonate resin obtained by such a production method (production method of (2)) with separately produced component A-1-1-1 and / or component A-1-1-2.

[0030] In this invention, the viscosity-average molecular weight is first calculated using the following formula: specific viscosity (η ＳＰ The specific viscosity (η) was determined using an Ostwald viscometer from a solution prepared by dissolving 0.7 g of polycarbonate resin in 100 ml of methylene chloride at 20°C. ＳＰ ) = (t - t ０ ) / t ０ [t ０ [where θ is the number of seconds for the methylene chloride to fall, and t is the number of seconds for the sample solution to fall] The specific viscosity (η) was determined. ＳＰThe viscosity-average molecular weight M is calculated from the following formula: η ＳＰ / c = [η] + 0.45 × [η] ２ c (where [η] is the intrinsic viscosity) [η] = 1.23 × 10 －４ M ０．８３ c = 0.7 The viscosity-average molecular weight of the polycarbonate resin in the flame-retardant polycarbonate resin composition of the present invention is calculated in the following manner. That is, the composition is mixed with methylene chloride in an amount 20 to 30 times its weight to dissolve the soluble components in the composition. These soluble components are collected by Celite filtration. The solvent is then removed from the obtained solution. The solid after solvent removal is thoroughly dried to obtain a solid of the components that dissolve in methylene chloride. The specific viscosity at 20°C is determined from a solution obtained by dissolving 0.7 g of this solid in 100 ml of methylene chloride in the same manner as above, and the viscosity-average molecular weight M is calculated from this specific viscosity in the same manner as above.

[0031] A polycarbonate-polydiorganosiloxane copolymer resin can also be used as the polycarbonate resin (component A) of the present invention. By using a polycarbonate-polyorganosiloxane copolymer resin as component A, chemical resistance and impact resistance can sometimes be improved. The polycarbonate-polydiorganosiloxane copolymer resin is preferably a copolymer resin consisting of units derived from a divalent phenol represented by the following general formula (1) and units derived from a hydroxyaryl-terminated polydiorganosiloxane represented by the following general formula (3).

[0032]

[0033] [In the above general formula (1), R １ and R ２Each of these independently represents a group selected from the group consisting of a hydrogen atom, a halogen atom, an alkyl group having 1 to 18 carbon atoms, an alkoxy group having 1 to 18 carbon atoms, a cycloalkyl group having 6 to 20 carbon atoms, a cycloalkoxy group having 6 to 20 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, an aryl group having 6 to 14 carbon atoms, an aryloxy group having 6 to 14 carbon atoms, an aralkyl group having 7 to 20 carbon atoms, an aralkyloxy group having 7 to 20 carbon atoms, a nitro group, an aldehyde group, a cyano group, and a carboxyl group. If there are multiple groups of each, they may be the same or different. e and f are integers from 1 to 4, and W is at least one group selected from the group consisting of a single bond or a group represented by the general formula (2) below.

[0034]

[0035] [In the above general formula (2), R １１ , R １２ , R １３ , R １４ , R １５ , R １６ , R １７ and R １８ Each of these independently represents a group selected from the group consisting of a hydrogen atom, an alkyl group having 1 to 18 carbon atoms, an aryl group having 6 to 14 carbon atoms, and an aralkyl group having 7 to 20 carbon atoms, R １９ and R ２０ Each of these independently represents a group selected from the group consisting of a hydrogen atom, a halogen atom, an alkyl group having 1 to 18 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, a cycloalkyl group having 6 to 20 carbon atoms, a cycloalkoxy group having 6 to 20 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, an aryl group having 6 to 14 carbon atoms, an aryloxy group having 6 to 10 carbon atoms, an aralkyl group having 7 to 20 carbon atoms, an aralkyloxy group having 7 to 20 carbon atoms, a nitro group, an aldehyde group, a cyano group, and a carboxyl group. If there are multiple groups, they may be the same or different, and g is an integer from 1 to 10, and h is an integer from 4 to 7.

[0036]

[0037] [In the above general formula (3), R ３ , R４ , R ５ , R ６ , R ７ and R ８ Each is independently a hydrogen atom, a C1-C12 alkyl group, or a C6-C12 substituted or unsubstituted aryl group, R ９ and R １０ Each of the following is independently a hydrogen atom, a halogen atom, an alkyl group with 1 to 10 carbon atoms, and an alkoxy group with 1 to 10 carbon atoms, where p is a natural number, q is 0 or a natural number, and p+q is a natural number between 10 and 300. X is a divalent aliphatic group with 2 to 8 carbon atoms.

[0038] Examples of divalent phenols (I) represented by general formula (1) include 4,4'-dihydroxybiphenyl, bis(4-hydroxyphenyl)methane, 1,1-bis(4-hydroxyphenyl)ethane, 1,1-bis(4-hydroxyphenyl)-1-phenylethane, 2,2-bis(4-hydroxyphenyl)propane, 2,2-bis(4-hydroxy-3-methylphenyl)propane, 1,1-bis(4-hydroxyphenyl)-3,3,5-trimethylcyclohexane, 2,2-bis(4-hydroxy-3,3'-biphenyl)propane, and 2,2- Bis(4-hydroxy-3-isopropylphenyl)propane, 2,2-bis(3-t-butyl-4-hydroxyphenyl)propane, 2,2-bis(4-hydroxyphenyl)butane, 2,2-bis(4-hydroxyphenyl)octane, 2,2-bis(3-bromo-4-hydroxyphenyl)propane, 2,2-bis(3,5-dimethyl-4-hydroxyphenyl)propane, 2,2-bis(3-cyclohexyl-4-hydroxyphenyl)propane, 1,1-bis(3-cyclohexyl-4-hydroxyphenyl)cyclohexane, bis(4-H hydroxyphenyl)diphenylmethane, 9,9-bis(4-hydroxyphenyl)fluorene, 9,9-bis(4-hydroxy-3-methylphenyl)fluorene, 1,1-bis(4-hydroxyphenyl)cyclohexane, 1,1-bis(4-hydroxyphenyl)cyclopentane, 4,4'-dihydroxydiphenyl ether, 4,4'-dihydroxy-3,3'-dimethyldiphenyl ether, 4,4'-sulfonyldiphenol, 4,4'-dihydroxydiphenyl sulfoxide, 4,4'-dihydroxydiphenyl sulfide, 2,2'- Dimethyl-4,4'-sulfonyldiphenol, 4,4'-dihydroxy-3,3'-dimethyldiphenyl sulfoxide, 4,4'-dihydroxy-3,3'-dimethyldiphenyl sulfide, 2,2'-diphenyl-4,4'-sulfonyldiphenol, 4,4'-dihydroxy-3,3'-diphenyldiphenyl sulfoxide, 4,4'-dihydroxy-3,3'-diphenyldiphenyl sulfide, 1,3-bis{2-(4-hydroxyphenyl)propyl}benzene, 1,4-bis{2-(4-hydroxyphenyl)propyl}benzene, 1,Examples include 4-bis(4-hydroxyphenyl)cyclohexane, 1,3-bis(4-hydroxyphenyl)cyclohexane, 4,8-bis(4-hydroxyphenyl)tricyclo[5.2.1.02,6]decane, 4,4'-(1,3-adamantanediyl)diphenol, and 1,3-bis(4-hydroxyphenyl)-5,7-dimethyladamantane.

[0039] Among these, 1,1-bis(4-hydroxyphenyl)-1-phenylethane, 2,2-bis(4-hydroxyphenyl)propane, 2,2-bis(4-hydroxy-3-methylphenyl)propane, 1,1-bis(4-hydroxyphenyl)cyclohexane, 1,1-bis(4-hydroxyphenyl)-3,3,5-trimethylcyclohexane, 4,4'-sulfonyldiphenol, 2,2'-dimethyl-4,4'-sulfonyldiphenol, 9,9-bis(4-hydroxy-3-methylphenyl)fluorene, 1,3-bis{2-(4-hydroxyphenyl)propyl}benzene, and 1,4-bis{2-(4-hydroxyphenyl)propyl}benzene are preferred, and 2,2-bis(4-hydroxyphenyl)propane, 1,1-bis(4-hydroxyphenyl)cyclohexane (BPZ), 4,4'-sulfonyldiphenol, and 9,9-bis(4-hydroxy-3-methylphenyl)fluorene are particularly preferred. Among these, 2,2-bis(4-hydroxyphenyl)propane, which has excellent strength and good durability, is the most suitable. These may be used individually or in combination of two or more.

[0040] As the hydroxyaryl-terminated polydiorganosiloxane represented by the above general formula (3), the following compounds are preferably used, for example.

[0041]

[0042] Hydroxyaryl-terminated polydiorganosiloxanes (II) can be easily produced by hydrosiliculation reaction of olefinic unsaturated carbon-carbon bonded phenols, preferably vinylphenol, 2-allylphenol, isopropenylphenol, and 2-methoxy-4-allylphenol, to the ends of a polysiloxane chain having a predetermined degree of polymerization. Among these, (2-allylphenol)-terminated polydiorganosiloxanes and (2-methoxy-4-allylphenol)-terminated polydiorganosiloxanes are preferred, and (2-allylphenol)-terminated polydimethylsiloxanes and (2-methoxy-4-allylphenol)-terminated polydimethylsiloxanes are particularly preferred. Hydroxyaryl-terminated polydiorganosiloxanes (II) preferably have a molecular weight distribution (Mw / Mn) of 3 or less. Furthermore, in order to exhibit excellent low outgassing and low-temperature impact resistance during high-temperature molding, such molecular weight distribution (Mw / Mn) is more preferably 2.5 or less, and even more preferably 2 or less. If the upper limit of this suitable range is exceeded, the amount of outgassing during high-temperature molding increases, and the low-temperature impact resistance may be poor.

[0043] Furthermore, in order to achieve high impact resistance, the degree of diorganosiloxane polymerization (p+q) of the hydroxyaryl-terminated polydiorganosiloxane (II) is appropriately set to 10 to 300. This degree of diorganosiloxane polymerization (p+q) is preferably 10 to 200, more preferably 12 to 150, and even more preferably 14 to 100. Below the lower limit of this preferred range, the impact resistance characteristic of polycarbonate-polydiorganosiloxane copolymers is not effectively exhibited, and above the upper limit of this preferred range, appearance defects appear.

[0044] The polydiorganosiloxane content in the polycarbonate-polydiorganosiloxane copolymer resin used in component A is preferably 0.1 to 50% by weight. More preferably, the polydiorganosiloxane content is 0.5 to 30% by weight, and even more preferably 1 to 20% by weight. Above the lower limit of this preferred range, excellent impact resistance and flame retardancy are obtained, and below the upper limit of this preferred range, a stable appearance less affected by molding conditions is easily obtained. The degree of polydiorganosiloxane polymerization and polydiorganosiloxane content are: １ It can be calculated by H-NMR measurement.

[0045] In the present invention, only one hydroxyaryl-terminated polydiorganosiloxane (II) may be used, or two or more may be used. Furthermore, other comonomers other than the above-mentioned divalent phenol (I) and hydroxyaryl-terminated polydiorganosiloxane (II) may be used in combination in an amount of 10% by weight or less relative to the total weight of the copolymer, as long as it does not interfere with the present invention.

[0046] In the present invention, a mixed solution containing an oligomer having terminal chloroformate groups is prepared in advance by the reaction of divalent phenol(I) and a carbonate ester-forming compound in a mixture of a water-insoluble organic solvent and an alkaline aqueous solution.

[0047] In generating the divalent phenol(I) oligomer, the entire amount of divalent phenol(I) used in the method of the present invention may be converted into an oligomer at once, or a portion of it may be added as a reaction material to the subsequent interfacial polycondensation reaction as a post-added monomer. The post-added monomer is added to expedite the subsequent polycondensation reaction, and does not need to be added if unnecessary. The method of this oligomer generation reaction is not particularly limited, but it is generally preferred to carry it out in a solvent in the presence of an acid binder.

[0048] The proportion of ester-forming compounds used can be adjusted as appropriate, taking into account the stoichiometric ratio (equivalent) of the reaction. Furthermore, when using gaseous ester-forming compounds such as phosgene, a suitable method is to bubble them into the reaction system.

[0049] Examples of acid binders include alkali metal hydroxides such as sodium hydroxide and potassium hydroxide, alkali metal carbonates such as sodium carbonate and potassium carbonate, organic bases such as pyridine, or mixtures thereof. The proportion of acid binder used should be determined appropriately, taking into account the stoichiometric ratio (equivalents) of the reaction, as described above. Specifically, it is preferable to use 2 equivalents or a slightly excess amount of acid binder relative to the number of moles of divalent phenol(I) used to form the oligomer (usually 1 mole corresponds to 2 equivalents).

[0050] As the aforementioned solvent, various reaction-inert solvents, such as those used in the production of known polycarbonates, can be used individually or as a mixed solvent. Typical examples include hydrocarbon solvents such as xylene, and halogenated hydrocarbon solvents such as methylene chloride and chlorobenzene. Halogenated hydrocarbon solvents such as methylene chloride are particularly preferred.

[0051] There are no particular restrictions on the reaction pressure for oligomer formation; it can be atmospheric pressure, pressurized pressure, or reduced pressure, but it is usually advantageous to carry out the reaction under atmospheric pressure. The reaction temperature is selected from the range of -20 to 50°C, and since polymerization is often exothermic, it is desirable to cool the reaction with water or ice. The reaction time depends on other conditions and cannot be specified in general, but it is usually carried out in 0.2 to 10 hours. The pH range for the oligomer formation reaction is the same as that of known interfacial reaction conditions, and the pH is always adjusted to 10 or higher.

[0052] In this invention, a mixed solution containing an oligomer of divalent phenol (I) having terminal chloroformate groups is obtained, and while stirring the mixed solution, a hydroxyaryl-terminated polydiorganosiloxane (II) represented by general formula (4), which has been highly purified to a molecular weight distribution (Mw / Mn) of 3 or less, is added to the divalent phenol (I), and the hydroxyaryl-terminated polydiorganosiloxane (II) and the oligomer are subjected to interfacial polycondensation to obtain a polycarbonate-polydiorganosiloxane copolymer.

[0053]

[0054] (In the above general formula (4), R ３ , R ４ , R ５ , R ６ , R ７ and R ８ Each is independently a hydrogen atom, a C1-C12 alkyl group, or a C6-C12 substituted or unsubstituted aryl group, R ９ and R １０ Each of the following is independently a hydrogen atom, a halogen atom, an alkyl group with 1 to 10 carbon atoms, and an alkoxy group with 1 to 10 carbon atoms, where p is a natural number, q is 0 or a natural number, and p+q is a natural number between 10 and 300. X is a divalent aliphatic group with 2 to 8 carbon atoms.

[0055] When carrying out an interfacial polycondensation reaction, an acid binder may be added as appropriate, taking into consideration the stoichiometric ratio (equivalent) of the reaction. Examples of acid binders include alkali metal hydroxides such as sodium hydroxide and potassium hydroxide, alkali metal carbonates such as sodium carbonate and potassium carbonate, organic bases such as pyridine, or mixtures thereof. Specifically, when adding a portion of the hydroxyaryl-terminated polydiorganosiloxane (II) or the divalent phenol (I) as described above as a post-added monomer to this reaction step, it is preferable to use 2 equivalents or an excess amount of alkali relative to the total number of moles of the post-added divalent phenol (I) and hydroxyaryl-terminated polydiorganosiloxane (II) (usually 1 mole corresponds to 2 equivalents).

[0056] The polycondensation reaction between the divalent phenol (I) oligomer and the hydroxyaryl-terminated polydiorganosiloxane (II) is carried out by vigorously stirring the above mixture.

[0057] In such polymerization reactions, end-terminating agents or molecular weight modifiers are commonly used. Examples of end-terminating agents include compounds having a monovalent phenolic hydroxyl group, such as ordinary phenols, p-tert-butylphenol, p-cumylphenol, and tribromophenol, as well as long-chain alkylphenols, aliphatic carboxylic acid chlorides, aliphatic carboxylic acids, alkyl hydroxybenzoates, hydroxyphenylalkylates, and alkyl etherphenols. The amount used is in the range of 100 to 0.5 moles, preferably 50 to 2 moles, per 100 moles of all divalent phenolic compounds used, and it is naturally possible to use two or more compounds in combination.

[0058] To accelerate the polycondensation reaction, a catalyst such as a tertiary amine like triethylamine or a quaternary ammonium salt may be added. The reaction time for such polymerization is preferably 30 minutes or more, more preferably 50 minutes or more. Optionally, a small amount of antioxidant such as sodium sulfite or hydrosulfide may be added.

[0059] Branching agents can be used in combination with the above-mentioned divalent phenolic compounds to form branched polycarbonate-polydiorganosiloxanes. Examples of trifunctional or polyfunctional aromatic compounds used in such branched polycarbonate-polydiorganosiloxane copolymer resins include phloroglucin, phloroglucid, or 4,6-dimethyl-2,4,6-tris(4-hydroxyphenyl)heptene-2,2,4,6-trimethyl-2,4,6-tris(4-hydroxyphenyl)heptane, 1,3,5-tris(4-hydroxyphenyl)benzene, 1,1,1-tris(4-hydroxyphenyl)ethane, 1,1,1-tris(3,5-dimethyl-4-hydroxyphenyl)ethane, 2,6-bis(2-hydroxy-5-methylbenzyl)-4-methylphenol, and 4-{4-[1 Examples include trisphenols such as 1-bis(4-hydroxyphenyl)ethyl]benzene-α,α-dimethylbenzylphenol, tetra(4-hydroxyphenyl)methane, bis(2,4-dihydroxyphenyl)ketone, 1,4-bis(4,4-dihydroxytriphenylmethyl)benzene, or trimellitic acid, pyromellitic acid, benzophenonetetracarboxylic acid and their acid chlorides, among which 1,1,1-tris(4-hydroxyphenyl)ethane and 1,1,1-tris(3,5-dimethyl-4-hydroxyphenyl)ethane are preferred, and 1,1,1-tris(4-hydroxyphenyl)ethane is particularly preferred. The proportion of polyfunctional compounds in the branched polycarbonate-polydiorganosiloxane copolymer resin is preferably 0.001 to 1 mol%, more preferably 0.005 to 0.9 mol%, even more preferably 0.01 to 0.8 mol%, and particularly preferably 0.05 to 0.4 mol%, of the total amount of aromatic polycarbonate-polydiorganosiloxane copolymer resin. １ It can be calculated by H-NMR measurement.

[0060] The reaction pressure can be reduced, atmospheric, or pressurized, but it is usually preferable to use atmospheric pressure or the self-pressure of the reaction system. The reaction temperature is selected from the range of -20 to 50°C, and since polymerization often generates heat, water cooling or ice cooling is desirable. The reaction time varies depending on other conditions such as the reaction temperature and cannot be specified in general terms, but it is usually carried out in 0.5 to 10 hours.

[0061] Depending on the circumstances, the obtained polycarbonate-polydiorganosiloxane copolymer resin can be subjected to appropriate physical treatment (mixing, fractionation, etc.) and / or chemical treatment (polymer reaction, crosslinking, partial decomposition, etc.) to obtain a polycarbonate-polydiorganosiloxane copolymer resin with a desired reduced viscosity [ηsp / c].

[0062] The resulting reaction product (crude product) can be recovered as a polycarbonate-polydiorganosiloxane copolymer resin of the desired purity (degree of purification) by various post-treatment methods, such as known separation and purification methods.

[0063] The average size of polydiorganosiloxane domains in a polycarbonate-polydiorganosiloxane copolymer resin molded product is preferably in the range of 1 to 40 nm. More preferably, this average size is 1 to 30 nm, and even more preferably 5 to 25 nm. Below the lower limit of this preferred range, impact resistance and flame retardancy are not sufficiently exhibited, and above the upper limit of this preferred range, impact resistance may not be stably exhibited. This provides a flame-retardant polycarbonate resin composition with excellent impact resistance and appearance.

[0064] The average domain size of the polydiorganosiloxane domains in the polycarbonate-polydiorganosiloxane copolymer resin molded product in this invention was evaluated by small-angle X-ray scattering (SAXS). Small-angle X-ray scattering is a method for measuring diffuse scattering and diffraction occurring in the small-angle region with a scattering angle (2θ) < 10° or less. In this small-angle X-ray scattering method, if there are regions with different electron densities of about 1 to 100 nm in size in the material, diffuse scattering of X-rays is measured due to the difference in electron density. The particle size of the object to be measured is determined based on this scattering angle and scattering intensity. In polycarbonate-polydiorganosiloxane copolymer resins, where polydiorganosiloxane domains are dispersed in a polycarbonate polymer matrix to form an aggregated structure, diffuse scattering of X-rays occurs due to the difference in electron density between the polycarbonate matrix and the polydiorganosiloxane domains. The scattering intensity I is measured at each scattering angle (2θ) in the range of less than 10° to obtain a small-angle X-ray scattering profile. Assuming that the polydiorganosiloxane domains are spherical and that there is variation in particle size distribution, the average size of the polydiorganosiloxane domains is determined by simulating with commercially available analysis software using hypothetical particle sizes and a hypothetical particle size distribution model. Small-angle X-ray scattering allows for accurate, simple, and reproducible measurement of the average size of polydiorganosiloxane domains dispersed in a polycarbonate polymer matrix, which cannot be accurately measured by transmission electron microscopy. The average domain size refers to the numerical average of the individual domain sizes.

[0065] The term "average domain size" used in relation to this invention refers to the measured value obtained by measuring the 1.0 mm thick portion of a three-tiered plate prepared by the method described in the examples using the small-angle X-ray scattering method. Furthermore, the analysis was performed using an isolated particle model that does not consider interparticle interactions (interparticle interference).

[0066] Furthermore, recycled polycarbonate resin, which is made from used products, can also be used as the polycarbonate resin. Preferred used products include various glazing materials such as soundproof walls, automobile windows, translucent roofing materials and automobile sunroofs, transparent components such as windshields and automobile headlamp lenses, containers such as water bottles, light guide plates, eyeglass lenses, and optical recording media. In addition, crushed materials obtained from unsuitable products, sprues, runners, etc., or pellets obtained by melting them can also be used.

[0067] (Component B: Polybutylene terephthalate resin) The resin composition of the present invention contains polybutylene terephthalate resin as component B. Polybutylene terephthalate resin is obtained by polycondensation of terephthalic acid or its ester-forming derivative with a C4 alkylene glycol or its ester-forming derivative. Alternatively, the polybutylene terephthalate resin may be a copolymer containing 70% or more of itself by weight.

[0068] Other dibasic acid components besides terephthalic acid and its lower alcohol esters include aliphatic and aromatic polybasic acids such as isophthalic acid, naphthalenedicarboxylic acid, adipic acid, sebacic acid, trimellitic acid, and succinic acid, or their ester-forming derivatives. Other glycol components besides 1,4-butanediol include ordinary alkylene glycols such as ethylene glycol, diethylene glycol, propylene glycol, trimethylene glycol, hexamethylene glycol, neopentyl glycol, cyclohexanedimethanol, etc., lower alkylene glycols such as 1,3-octanediol, aromatic alcohols such as bisphenol A and 4,4'-dihydroxybiphenyl, alkylene oxide adduct alcohols such as the 2-mol ethylene oxide adduct of bisphenol A and the 3-mol propylene oxide adduct of bisphenol A, polyhydroxy compounds such as glycerin and pentaerythritol, or their ester-forming derivatives.

[0069] In the present invention, any of the polybutylene terephthalates produced by polycondensation using the above-mentioned compounds as monomer components can be used as component B of the present invention, either alone or in a mixture of two or more.

[0070] The intrinsic viscosity of the polybutylene terephthalate resin used in the present invention is not particularly limited, but is preferably 0.4 to 1.5. A more preferred range for the intrinsic viscosity is 0.45 to 1.4, and even more preferably 0.5 to 1.3. If the intrinsic viscosity of the polybutylene terephthalate resin is less than 0.4, sufficient impact properties and chemical resistance may not be obtained, and if it is greater than 1.5, the fluidity during injection molding decreases, and appearance defects such as flow marks and poor coloring may occur. The intrinsic viscosity of the polybutylene terephthalate resin is measured by dissolving the polybutylene terephthalate resin in orthochlorophenol and measuring it at a temperature of 35°C.

[0071] In a total of 100 parts by weight of components A and B, the content of component A is 40 to 70 parts by weight, preferably 45 to 65 parts by weight, more preferably 50 to 60 parts by weight, and the content of component B is 60 to 30 parts by weight, preferably 55 to 35 parts by weight, more preferably 50 to 40 parts by weight. If the content of component B is less than 30 parts by weight, sufficient chemical resistance cannot be obtained, and if it exceeds 60 parts by weight, flame retardancy and impact resistance will decrease.

[0072] (Component C: Brominated polycarbonate flame retardant) The resin composition of the present invention contains a brominated polycarbonate flame retardant as component C. The brominated polycarbonate flame retardant has excellent heat resistance and can significantly improve flame retardancy. The brominated polycarbonate flame retardant used in the present invention is a brominated polycarbonate compound in which the constituent units represented by the following formula (5) preferably make up at least 60 mol%, more preferably at least 80 mol%, of the total constituent units, and particularly preferably substantially consists of constituent units represented by the following formula (5).

[0073]

[0074] (In formula (5), X is a bromine atom, R is an alkylene group having 1 to 4 carbon atoms, an alkylidene group having 1 to 4 carbon atoms, or -SO２ -.) In addition, in formula (5), R is preferably a methylene group, an ethylene group, an isopropylidene group, -SO ２ - Particularly preferably exhibits an isopropylidene group.

[0075] The brominated polycarbonate flame retardant preferably has a small amount of residual chloroformate groups at the ends, with a terminal chlorine content of 0.3 ppm or less, and more preferably 0.2 ppm or less. This terminal chlorine content can be determined by dissolving the sample in methylene chloride, adding 4-(p-nitrobenzyl)pyridine to react with the terminal chlorine (terminal chloroform), and measuring the result using a UV-Vis spectrophotometer (Hitachi U-3200). When the terminal chlorine content is 0.3 ppm or less, the thermal stability of the flame-retardant polycarbonate resin composition is improved, allowing for molding at even higher temperatures, and as a result, a resin composition with superior moldability may be provided.

[0076] Furthermore, it is preferable that the brominated polycarbonate flame retardant has a small number of remaining hydroxyl group terminals. More specifically, it is preferable that the amount of terminal hydroxyl groups is 0.0005 moles or less, and more preferably 0.0003 moles or less, per mole of constituent units of the brominated polycarbonate flame retardant. The amount of terminal hydroxyl groups is determined by dissolving the sample in deuterated chloroform. １ This can be determined by measurement using the 1H-NMR method. Such a high amount of terminal hydroxyl groups may further improve the thermal stability of the flame-retardant polycarbonate resin composition.

[0077] The specific viscosity of the brominated polycarbonate flame retardant is preferably 0.015 to 0.1, more preferably 0.015 to 0.08. The specific viscosity of the brominated polycarbonate flame retardant was calculated according to the specific viscosity calculation formula used when calculating the viscosity-average molecular weight of the polycarbonate resin, which is component A of the present invention, as described above.

[0078] The content of component C is 15 to 30 parts by weight, preferably 17 to 28 parts by weight, and more preferably 19 to 26 parts by weight, based on 100 parts by weight of the total of components A and B. If the content of component C is less than 15 parts by weight, sufficient flame retardancy cannot be obtained, and if it exceeds 30 parts by weight, chemical resistance and impact resistance will decrease.

[0079] (Component D: Phosphazene containing 98.5 mol% or more of a phosphophazene cyclic trimer) The flame-retardant polycarbonate resin composition of the present invention contains phosphophazene containing 98.5 mol% or more of a phosphophazene cyclic trimer as component D. The phosphophazene is not particularly limited as long as it does not contain halogen atoms and has a phosphophazene structure in its molecule. The phosphophazene structure referred to here is the structure represented by the formula: -P(R2)=N- [wherein R2 is an organic group]. Phosphazene is represented by general formulas (6) and (7).

[0080]

[0081] (In the formula, X １ , X ２ , X ３ , X ４ X represents an organic group that does not contain hydrogen, hydroxyl, amino, or halogen atoms. Also, n represents an integer from 3 to 10. In the above formulas (6) and (7), X １ , X ２ , X ３ , X ４ Examples of organic groups that do not contain halogen atoms include alkoxy groups, phenyl groups, amino groups, and allyl groups.

[0082] The phosphazene component D must contain 98.5 mol% or more of a phosphazene cyclic trimer, preferably in the range of 99 mol% to 100 mol%, and more preferably in the range of 99.5 mol% to 100 mol%. If the phosphazene cyclic trimer content is less than 98.5 mol%, the thermal stability will decrease.

[0083] General methods for producing phosphazenes are described in European Patent Publication No. 728811 and International Publication No. 97 / 40092, among others.

[0084] During the manufacturing process, phosphazene produces cyclic tetramers and higher-grade oligomers as by-products in addition to cyclic trimers. However, the content of phosphazene cyclic trimers can be increased by purification using methods such as column chromatography.

[0085] Furthermore, the content of phosphazene cyclic trimers in phosphazene is ３１ It can be quantified by PNMR (chemical shift, δ trimer 6.5–10.0 ppm, δ tetramer -10 to -13.5 ppm, higher-grade oligomers than δ -16.5 to -25.0 ppm).

[0086] The content of component D is 4 to 10 parts by weight, preferably 4.5 to 9 parts by weight, and more preferably 5 to 8 parts by weight, per 100 parts by weight of component A. If the content of component D is less than 4 parts by weight, the flame retardant effect is not obtained, and if it exceeds 10 parts by weight, the chemical resistance decreases.

[0087] (Component E: Impact modifier) ​​The flame-retardant polycarbonate resin composition of the present invention contains an impact modifier as component E. The impact modifier is preferably a graft polymer obtained by graft polymerizing at least one compound containing a (meth)acrylic acid ester compound onto one rubber selected from the group consisting of butadiene rubber, acrylic rubber, and silicone-acrylic composite rubber, and a graft polymer having a core-shell structure is more preferred. The core-shell type graft polymer is a graft copolymer obtained by copolymerizing a rubber component with a glass transition temperature of 10°C or less as the core, with one or more monomers selected from vinyl compounds copolymerizable with these, including (meth)acrylic acid ester compounds and aromatic alkenyl compounds, as the shell.

[0088] Examples of rubber components for component E include butadiene rubber, butadiene-acrylic composite rubber, acrylic rubber, silicone-acrylic composite rubber, isobutylene-silicone composite rubber, isoprene rubber, styrene-butadiene rubber, chloroprene rubber, ethylene-propylene rubber, nitrile rubber, ethylene-acrylic rubber, silicone rubber, epichlorohydrin rubber, fluororubber, and those in which hydrogen is added to the unsaturated bond portion. Furthermore, the glass transition temperature of the rubber component is preferably -10°C or lower, more preferably -30°C or lower. From these points of view, butadiene rubber and acrylic-silicone-acrylic composite rubber are particularly preferred as rubber components. A composite rubber refers to a rubber obtained by copolymerizing two types of rubber components or a rubber obtained by polymerizing them to take an IPN structure in which they are intertwined with each other so that they cannot be separated.

[0089] Aromatic vinyl compounds copolymerized with rubber components as the shell of a core-shell type graft polymer include styrene, α-methylstyrene, p-methylstyrene, alkoxystyrene, and halogenated styrene. Examples of acrylic acid esters include methyl acrylate, ethyl acrylate, butyl acrylate, cyclohexyl acrylate, and octyl acrylate, while examples of methacrylic acid esters include methyl methacrylate, ethyl methacrylate, butyl methacrylate, cyclohexyl methacrylate, and octyl methacrylate, with methyl methacrylate being particularly preferred. Among these, it is especially preferable to include methacrylic acid esters such as methyl methacrylate as essential components, and it is even more preferable to omit aromatic vinyl components from the viewpoint of mechanical properties, flame retardancy, and chemical resistance. More specifically, it is preferable that the methacrylic acid ester be contained in an amount of 10% by weight or more, more preferably 15% by weight or more, in 100% by weight of the graft component (or 100% by weight of the shell in the case of a core-shell type polymer). Elastic polymers containing rubber components with a glass transition temperature of 10°C or lower may be produced by any of the polymerization methods: bulk polymerization, solution polymerization, suspension polymerization, or emulsion polymerization. The copolymerization method may be single-stage grafting or multi-stage grafting. It may also be a mixture with copolymers consisting only of graft components produced as by-products during manufacturing. In addition to the general emulsion polymerization method, other polymerization methods include soap-free polymerization using initiators such as potassium persulfate, seed polymerization, and two-stage swelling polymerization. Furthermore, in suspension polymerization, methods may be used in which the aqueous phase and monomer phase are held separately and accurately supplied to a continuous disperser, and the particle size is controlled by the rotation speed of the disperser. In continuous manufacturing methods, the monomer phase may be supplied through a small-diameter orifice or porous filter of several to tens of micrometers in diameter into an aqueous liquid with dispersibility to control the particle size. In the case of core-shell type graft polymers, the reaction may be single-stage or multi-stage for both the core and shell.

[0090] Such polymers are commercially available and easily obtainable. For example, among those with butadiene rubber as the main component, there is the Metabren E series manufactured by Mitsubishi Chemical Corporation (for example, E-875A, in which the shell component is mainly methyl methacrylate, and E-870A, in which the shell component is mainly methyl methacrylate-styrene). Among those with acrylic rubber as the main component, there is the W series manufactured by Mitsubishi Chemical Corporation (for example, W-600A, in which the shell component is mainly methyl methacrylate). Among those with silicone-acrylic composite rubber as the main component, there is the Metabren S series manufactured by Mitsubishi Chemical Corporation (for example, S-2001, S-2030, in which the shell component is mainly methyl methacrylate).

[0091] The content of component E is 5 to 15 parts by weight, preferably 6 to 14 parts by weight, and more preferably 7 to 13 parts by weight, based on 100 parts by weight of the total of components A and B. If the content of component E is less than 5 parts by weight, sufficient chemical resistance and impact resistance cannot be obtained, and if it exceeds 15 parts by weight, flame retardancy decreases.

[0092] (Component F: Transesterification Reaction Inhibitor) The flame-retardant polycarbonate resin composition of the present invention contains a transesterification reaction inhibitor as component F. Any compound that deactivates the transesterification reaction catalyst can be used as the transesterification reaction inhibitor without particular limitations, but phosphite compounds, phosphate compounds, phosphonitic acid compounds, phosphonic acid compounds and their esters, and tertiary phosphines are preferred. Among these, phosphate compounds and phosphite compounds are more preferred because they deactivate the transesterification reaction catalyst quickly, and phosphate compounds are particularly preferred.

[0093] Examples of phosphate compounds include tributyl phosphate, trimethyl phosphate, tricresyl phosphate, triphenyl phosphate, trichlorophenyl phosphate, triethyl phosphate, diphenyl cresyl phosphate, diphenyl monoorthoxenyl phosphate, tributoxyethyl phosphate, dibutyl phosphate, dioctyl phosphate, diisopropyl phosphate, stearyl acid phosphate, octadecyl phosphate, and stearyl acid phosphate metal salts.

[0094] Examples of phosphite compounds include trialkyl phosphites such as tridecyl phosphite, dialkyl monoaryl phosphites such as didecyl monophenyl phosphite, monoalkyldiaryl phosphites such as monobutyldiphenyl phosphite, triaryl phosphites such as triphenyl phosphite and tris(2,4-di-tert-butylphenyl) phosphite, distearyl pentaerythritol diphosphite, and bis(2,4-di-tert-butylphenyl) pentaerythritol. Examples include pentaerythritol phosphites such as tol diphosphite, bis(2,4-dicumylphenyl)pentaerythritol diphosphite and bis(2,6-di-tert-butyl-4-methylphenyl)pentaerythritol diphosphite, as well as cyclic phosphites such as 2,2-methylenebis(4,6-di-tert-butylphenyl)octyl phosphite and 2,2'-methylenebis(4,6-di-tert-butylphenyl)(2,4-di-tert-butylphenyl) phosphite.

[0095] The above transesterification inhibitors can be used alone or in combination of two or more.

[0096] The content of component F is 0.01 to 0.5 parts by weight, preferably 0.03 to 0.4 parts by weight, and more preferably 0.05 to 0.3 parts by weight, based on 100 parts by weight of the total of components A and B. If the content is less than 0.01 parts by weight, the transesterification reaction is promoted, resulting in a decrease in chemical resistance, flame retardancy, thermal stability, and impact resistance. If it exceeds 0.5 parts by weight, flame retardancy and chemical resistance decrease.

[0097] (Component G: Drip inhibitor) The flame-retardant polycarbonate resin composition of the present invention contains a drip inhibitor as component G. The inclusion of this drip inhibitor makes it possible to achieve good flame retardancy without impairing the physical properties of the molded product.

[0098] Examples of drip inhibitors include fluorine-containing polymers having fibril-forming ability. Such polymers include polytetrafluoroethylene, tetrafluoroethylene copolymers (e.g., tetrafluoroethylene / hexafluoropropylene copolymers), partially fluorinated polymers as described in U.S. Patent No. 4,379,910, and polycarbonate resins produced from fluorinated diphenols. Among these, polytetrafluoroethylene (hereinafter sometimes referred to as PTFE) is preferred.

[0099] Furthermore, in the present invention, coated branched PTFE can be used as a drip-preventing agent. Coated branched PTFE is a polytetrafluoroethylene mixture consisting of branched polytetrafluoroethylene particles and an organic polymer, and has a coating layer on the outside of the branched polytetrafluoroethylene consisting of an organic polymer, preferably a polymer containing styrene monomer-derived units and / or acrylic monomer-derived units. The coating layer is formed on the surface of the branched polytetrafluoroethylene. It is also preferable that the coating layer contains a copolymer of styrene monomers and acrylic monomers.

[0100] The content of component G is 0.1 to 1 part by weight, preferably 0.2 to 0.9 parts by weight, and more preferably 0.3 to 0.8 parts by weight, per 100 parts by weight of the total of components A and B. If the content is less than 0.1 parts by weight, sufficient flame retardancy cannot be obtained, and if it exceeds 1 part by weight, chemical resistance and impact resistance will decrease.

[0101] (Other Additives) (i) Phenolic Stabilizers The resin composition of the present invention may contain phenolic stabilizers. Phenolic stabilizers generally include hindered phenols, semi-hindered phenols, and less-hindered phenol compounds, but hindered phenol compounds are particularly preferred in terms of providing a heat-stable formulation for polycarbonate resins.

[0102] (ii) UV absorbers The flame-retardant polycarbonate resin composition of the present invention may contain UV absorbers. Examples of UV absorbers include compounds such as benzophenone-based, benzotriazole-based, hydroxyphenyltriazine-based, and cyclic iminoester-based compounds.

[0103] Furthermore, the above-mentioned ultraviolet absorber may also be a polymer-type ultraviolet absorber obtained by copolymerizing such ultraviolet-absorbing monomer and / or photostable monomer with a monomer such as alkyl (meth)acrylate, by adopting the structure of a monomer compound that can be radically polymerized. Suitable examples of the ultraviolet-absorbing monomer include compounds containing a benzotriazole skeleton, benzophenone skeleton, triazine skeleton, cyclic iminoester skeleton, and cyanoacrylate skeleton in the ester substituent of a (meth)acrylic acid ester. The above-mentioned ultraviolet absorbers can be used alone or in combination of two or more.

[0104] (iii) Hindered Amine Light Stabilizer The flame-retardant polycarbonate resin composition of the present invention may contain a hindered amine light stabilizer. Hindered amine light stabilizers are generally called HALS (Hindered Amine Light Stabilizer) and are compounds having a 2,2,6,6-tetramethylpiperidine skeleton in their structure.

[0105] Hindered amine light stabilizers are broadly classified into three types based on the bonding partner of the nitrogen atom in the piperidine skeleton: N-H type (hydrogen bonded to the nitrogen atom), N-R type (alkyl group (R) bonded to the nitrogen atom), and N-OR type (alkoxy group (OR) bonded to the nitrogen atom). However, when applied to polycarbonate resins, it is more preferable to use the low-basic N-R type or N-OR type from the viewpoint of the basicity of the hindered amine light stabilizer. Hindered amine light stabilizers can be used alone or in combination of two or more types.

[0106] (iv) Release Agent The flame-retardant polycarbonate resin composition of the present invention may further contain a release agent for the purpose of improving productivity during molding and reducing distortion of the molded product. Known release agents can be used. For example, saturated fatty acid esters, unsaturated fatty acid esters, polyolefin waxes (polyethylene wax, 1-alkene polymers, etc., including those modified with functional group-containing compounds such as acid modification), silicone compounds, fluorine compounds (fluorine oils such as polyfluoroalkyl ethers), paraffin wax, beeswax, etc. Among these, fatty acid esters and polyolefin waxes are preferred release agents.

[0107] (v) Dyes and Pigments The flame-retardant polycarbonate resin composition of the present invention can further contain various dyes and pigments to provide molded articles that exhibit diverse design properties. By incorporating fluorescent whitening agents or other fluorescent dyes that emit light, it is possible to provide even better design effects that take advantage of the emitted color. Furthermore, a flame-retardant polycarbonate resin composition that can be colored with a minute amount of dye and pigment and has vivid color development can also be provided.

[0108] (vi) Fillers The flame-retardant polycarbonate resin composition of the present invention may be blended with various fillers as reinforcing fillers, to the extent that the effects of the present invention are exhibited. Examples include silicate minerals, calcium carbonate, glass fibers, glass beads, glass balloons, glass milled fibers, glass flakes, carbon fibers, carbon flakes, carbon beads, carbon milled fibers, graphite, vapor-deposited ultrafine carbon fibers (fiber diameter less than 0.1 μm), carbon nanotubes (fiber diameter less than 0.1 μm and hollow), fullerenes, metal flakes, metal fibers, metal-coated glass fibers, metal-coated carbon fibers, metal-coated glass flakes, silica, metal oxide particles, metal oxide fibers, metal oxide balloons, and various whiskers (potassium titanate whiskers, aluminum borate whiskers, and basic magnesium sulfate, etc.). These reinforcing fillers may be included individually or in combination of two or more.

[0109] (vii) Other Additives In addition, the flame-retardant polycarbonate resin composition of the present invention may contain small amounts of well-known additives to impart various functions or improve the properties of the molded article. These additives are added in normal amounts as long as they do not impair the purpose of the present invention.

[0110] Examples of such additives include lubricants (e.g., PTFE particles), light diffusing agents (e.g., acrylic crosslinked particles, silicone crosslinked particles, ultrathin glass flakes, calcium carbonate particles), antistatic agents, nucleating agents, inorganic and organic antimicrobial agents, photocatalytic antifouling agents (e.g., fine-particle titanium dioxide, fine-particle zinc oxide), radical generators, infrared absorbers (heat absorbers), and photochromic agents.

[0111] (Manufacturing of Resin Composition) Any method can be used to manufacture the resin composition of the present invention. For example, components A to G and optionally other additives are thoroughly mixed using premixing means such as a V-type blender, Henschel mixer, mechanochemical device, or extruder mixer. Then, if necessary, the premix is ​​granulated using an extruder or briquetting machine. After that, it is melt-kneaded in a melt-kneader such as a vented twin-screw extruder, and then pelletized using a pelletizer.

[0112] Other methods include supplying each component independently to a melting and mixing machine, such as a vented twin-screw extruder, or pre-mixing a portion of each component before supplying it independently to the melting and mixing machine along with the remaining components.

[0113] Preferably, an extruder equipped with a vent capable of removing moisture from the raw material and volatile gases generated from the molten and kneaded resin is used. A vacuum pump is preferably installed in the vent to efficiently discharge the generated moisture and volatile gases to the outside of the extruder. It is also possible to install a screen in the zone in front of the extruder die to remove foreign matter mixed into the extrusion raw material, thereby removing foreign matter from the resin composition. Examples of such screens include wire mesh, screen changers, and sintered metal plates (disc filters, etc.).

[0114] Other types of melting and mixing machines include twin-screw extruders, Banbury mixers, mixing rolls, single-screw extruders, and multi-screw extruders with three or more shafts.

[0115] As described above, the extruded resin is either directly cut and pelletized, or strands are formed and then cut in a pelletizer to form pellets. If it is necessary to reduce the influence of external dust and other contaminants during pelletization, it is preferable to clean the atmosphere around the extruder. Furthermore, in the production of such pellets, various methods already proposed for polycarbonate resins for optical discs can be used to appropriately narrow the shape distribution of the pellets, reduce miscuts, reduce fine powder generated during transportation or transport, and reduce air bubbles (vacuum bubbles) generated inside the strands and pellets. These formulations can enable high-cycle molding and reduce the rate of defects such as silver. The shape of the pellets can be general shapes such as cylinders, prismatics, and spheres, but cylinders are more preferable. The diameter of such cylinders is preferably 1 to 5 mm, more preferably 1.5 to 4 mm, and even more preferably 2 to 3.3 mm. On the other hand, the length of the cylinders is preferably 1 to 30 mm, more preferably 2 to 5 mm, and even more preferably 2.5 to 3.5 mm.

[0116] (Molded articles made from the resin composition of the present invention) The resin composition of the present invention can be used to produce various products by injection molding pellets obtained by the method described above. In such injection molding, molded articles can be obtained using injection molding methods such as injection compression molding, injection press molding, gas-assisted injection molding, foam molding (including those by injection of supercritical fluid), insert molding, in-mold coating molding, heat-insulating mold molding, rapid heating and cooling mold molding, two-color molding, sandwich molding, and ultra-high-speed injection molding, depending on the purpose. The advantages of these various molding methods are already widely known. Furthermore, molding can be performed using either a cold runner method or a hot runner method.

[0117] Furthermore, the resin composition of the present invention can be used in the form of various irregularly shaped extruded products, sheets, films, etc., by extrusion molding. Inflation molding, calendering, and casting methods can also be used for forming sheets and films. It is also possible to form it as a heat-shrinkable tube by applying a specific stretching operation. The resin composition of the present invention can also be molded into products by rotational molding or blow molding.

[0118] The present inventor's current best-in-class embodiment of the invention is a combination of the preferred ranges of the above requirements, and a representative example is described in the following examples. Of course, the present invention is not limited to these embodiments.

[0119] The embodiments for carrying out the present invention are a combination of preferred ranges of the above requirements, and representative examples are described in the following examples. Of course, the present invention is not limited to these embodiments. The evaluation was carried out by the following method.

[0120] (i) Flame retardancy: A V test was performed in accordance with UL94 using UL test specimens obtained by the method described below. The flame retardancy level decreases in the order of V-0 > V-1 > V-2 > Out of specification. (ii) Thermal stability: The viscosity-average molecular weight of ISO tensile test specimens and pellets obtained by molding after being left in a cylinder for 5 minutes under the same conditions as described below was measured, and the decrease in viscosity-average molecular weight was calculated based on the following formula. The viscosity-average molecular weight was measured by the method described in the specification. (Decrease in viscosity-average molecular weight) = (Viscosity-average molecular weight of pellet) - (Viscosity-average molecular weight of molded product after 5 minutes of retention) (iii) Chemical resistance Using ISO tensile test specimens obtained by the method described below, a 1% strain was applied using the three-point bending test method, followed by the application of a medical disinfectant wipe (a medical disinfectant wipe mainly composed of quaternary ammonium salts, PDI Sani-Cloth AF3 Germicidal Disposable Wipe (product name) manufactured by Professional Disposables International, Inc.), and the specimen was left at 23°C for 168 hours before the appearance of the specimen was checked. The evaluation was carried out according to the following criteria. A: No surface roughness or cracks were observed after the test. B: Surface roughness was observed after the test, but no cracks were observed. C: Surface roughness and cracks were observed after the test. (iv) Impact resistance Using ISO bending test specimens with a thickness of 4 mm obtained by the method described below, the notched Charpy impact strength was measured in accordance with ISO 179 under an atmosphere of 23°C.

[0121] [Examples 1-16, Comparative Examples 1-14] Mixtures were supplied from the first feed port of the extruder with the compositions shown in Tables 1 and 2. The amount of mixture supplied was precisely measured using a measuring instrument [Kubota Corporation CWF]. Extrusion was performed using a 30 mmφ vented twin-screw extruder (Japan Steel Works Ltd. TEX30α-38.5BW-3V), with a screw rotation speed of 230 rpm, a discharge rate of 25 kg / h, and a vent vacuum of 3 kPa, by melt-kneading to obtain pellets. The extrusion temperature was 260°C from the first feed port to the die section. A portion of the obtained pellets was dried in a hot air circulating dryer at 90-100°C for 6 hours. Then, using an injection molding machine, ISO tensile test specimens (compliant with ISO 527-1 and ISO 527-2), ISO bending test specimens (compliant with ISO 178, ISO 179, ISO 75-1 and ISO 75-2), and UL test specimens (13 mm wide x 125 mm long x 1.5 mm thick) were prepared at a cylinder temperature of 260°C and a mold temperature of 70°C.

[0122] The components represented by the symbols in Tables 1 and 2 are as follows: (Component A) A-1: ​​Aromatic polycarbonate resin (polycarbonate resin powder with a viscosity-average molecular weight of 23,900, produced by a conventional method from bisphenol A and phosgene, manufactured by Teijin Limited, Panlite L-1250WP (product name)) A-2: Polycarbonate-polydiorganosiloxane copolymer resin (viscosity-average molecular weight of 25,000, PDMS content of 8.4%, PDMS degree of polymerization of 37, manufactured by Teijin Limited, Panlite W-0111) (Component B) B-1: Polybutylene terephthalate resin (intrinsic viscosity: 1.26 dl / g, manufactured by Changchun Artificial Resin Co., Ltd., 1100-211XG (product name)) (Component C) C-1: Brominated polycarbonate flame retardant (brominated carbonate oligomer having a bisphenol A skeleton, bromine content: 58.0%, manufactured by Teijin Limited) FG-8500 (product name) (Component D) D-1: A cyclic phenoxyphosphazene in which the k=1 trimer of formula (8) below contains 100 mol% D-2: A cyclic phenoxyphosphazene in which the k=1 trimer of formula (8) below contains 98.5 mol%, the k=2 tetramer contains 1 mol%, and the k=3 or higher polymer contains 0.5 mol D-3 (comparative example): A cyclic phenoxyphosphazene in which the k=1 trimer of formula (8) below contains 98 mol%, the k=2 tetramer contains 1.5 mol%, and the k=3 or higher polymer contains 0.5 mol D-4 (Comparative Example): A cyclic phenoxyphosphazene in which the content of the k=1 trimer in formula (8) below is 70 mol%, the content of the k=2 tetramer is 20 mol%, and the content of the k=3 or higher polymer is 10 mol%.

[0123]

[0124] (Component E) E-1: Impact modifier (graft copolymer having a core-shell structure with a core mainly composed of silicone-acrylic composite rubber and a shell mainly composed of methyl methacrylate, manufactured by Mitsubishi Chemical Corporation, Metabren S-2030 (product name)) (Component F) F-1: Transesterification inhibitor (octadecyl phosphate, manufactured by ADEKA Corporation, Adeka Stab AX-71 (product name)) F-2: Transesterification inhibitor (bis(2,4-di-tert-butylphenyl) pentaerythritol diphosphite, manufactured by Songwon Industrial, Co. Ltd., SONGNIOX 6260 PW (product name)) (Component G) G-1: Drip inhibitor (polytetrafluoroethylene, manufactured by Daikin Industries, Ltd., Polyflon MPA FA500H (product name))

[0125]

[0126]

Claims

1. A flame-retardant polycarbonate resin composition comprising 100 parts by weight in total, comprising 40 to 70 parts by weight of (A) polycarbonate resin (component A) and 60 to 30 parts by weight of polybutylene terephthalate resin (component B), with the following components: (C) 15 to 30 parts by weight of brominated polycarbonate-based flame retardant (component C), (D) 4 to 10 parts by weight of phosphazene (component D) containing 98.5 mol% or more of phosphazene cyclic trimer, (E) 5 to 15 parts by weight of impact modifier (component E), (F) transesterification reaction inhibitor (component F) 0.01 to 0.5 parts by weight, and (G) drip inhibitor (component G) 0.1 to 1 part by weight.

2. The flame-retardant polycarbonate resin composition according to claim 1, wherein component A is a polycarbonate-polydiorganosiloxane copolymer resin.

3. The flame-retardant polycarbonate resin composition according to claim 1 or 2, wherein component B is a polybutylene terephthalate resin having an intrinsic viscosity of 0.4 to 1.

5.

4. Component C is given by the following formula (5) (In formula (5), X is a bromine atom, R is an alkylene group having 1 to 4 carbon atoms, an alkylidene group having 1 to 4 carbon atoms, or -SO ２ A flame-retardant polycarbonate resin composition according to any one of claims 1 to 3, which is a brominated polycarbonate compound having a constituent unit represented by -.

5. The phosphazene cyclic trimer in component D is given by the following formula (8) A flame-retardant polycarbonate resin composition according to any one of claims 1 to 4, wherein the compound is represented by (in formula (8), k = 1).

6. The flame-retardant polycarbonate resin composition according to any one of claims 1 to 5, wherein component E is a graft polymer obtained by graft polymerizing at least one compound containing a (meth)acrylic acid ester compound onto one rubber selected from the group consisting of butadiene rubber, acrylic rubber, and silicone-acrylic composite rubber.

7. The flame-retardant polycarbonate resin composition according to any one of claims 1 to 6, wherein component F is at least one compound selected from the group consisting of phosphite compounds and phosphate compounds.

8. The flame-retardant polycarbonate resin composition according to any one of claims 1 to 7, wherein component G is a fluorine-containing polymer having fibril-forming ability.

9. A molded article obtained by molding a flame-retardant polycarbonate resin composition according to any one of claims 1 to 8.

10. A molded article according to claim 9, which is an exterior material for a medical device.

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