Flame-retardant thermoplastic resin compositions, molded articles and extended films

Abstract

This invention provides a flame-retardant thermoplastic resin composition that improves both flame retardancy and moisture resistance. The flame-retardant thermoplastic resin composition of this invention comprises a thermoplastic resin and a bis(phosphine oxide) compound represented by formula (1). Furthermore, in formula (1), R1 may be a substituent alkyl group, a substituent aryl group, or a divalent organic group represented by the formula: -Q1-Ar-Q2-[Ar may also be a substituent aryl group, Q1 and Q2 are each independently a substituent alkyl group with 1 or more and 10 or fewer carbon atoms.], and R2 to R5 are each independently a substituent alkyl group, a substituent aryl group, or a substituent alkoxy group.

Description

Technical Field

[0001] This invention relates to flame-retardant thermoplastic resin compositions and molded articles and extended films formed using the flame-retardant thermoplastic resin compositions. Prior Technology

[0002] Previously, flame-retardant thermoplastic resin compositions obtained by adding flame retardants to thermoplastic resins such as cyclic olefin ring-opening polymers (hereinafter referred to as "cyclic olefin ring-opening polymer hydrides") were used as molding materials for various molded articles to improve their flame retardancy.

[0003] Specifically, flame-retardant thermoplastic resin compositions, which are cyclic olefin ring-opening polymer hydrides of thermoplastic resins with excellent properties such as low moisture absorption, insulation, and impact resistance, are widely used as molding materials for films and other molded articles (see, for example, Patent Documents 1 and 2). Furthermore, Patent Document 1 uses an organic hypophosphite-based flame retardant such as aluminum diethylphosphite as a phosphorus-based flame retardant, while Patent Document 2 uses a phosphorus-based flame retardant such as aluminum diethylphosphite with a decomposition temperature in the range of 100°C to 500°C.

[0004] Patent Documents Patent Document 1, Japanese Patent Publication No. 2021-107508 Patent Document 2, Japanese Patent Publication No. 2014-101503 Summary of the Invention

[0005] However, the aforementioned conventional flame-retardant thermoplastic resin compositions have room for improvement in moisture resistance.

[0006] Therefore, the present invention aims to provide a flame-retardant thermoplastic resin composition that improves both flame retardancy and moisture resistance.

[0007] Furthermore, the present invention aims to provide molded articles and extended films with excellent flame retardancy and moisture resistance.

[0008] The inventors have diligently conducted research with the aim of solving the aforementioned problems. Then, the inventors discovered that by using a specified bis(phosphine oxide) compound as a flame retardant, the flame retardancy of the flame-retardant thermoplastic resin composition can be improved while simultaneously enhancing its moisture resistance, thus completing the present invention.

[0009] That is, this invention is intended to solve the above-mentioned problems. The flame-retardant thermoplastic resin composition of this invention is characterized by containing a thermoplastic resin and a bis(phosphine oxide) compound represented by the following formula (1). 『Transformation 1』 [In formula (1), R1 can be a substituent alkyl group, a substituent aryl group, or a divalent organogroup represented by formula: -Q1-Ar-Q2-[where Ar can be a substituent aryl group, Q1 and Q2 are each independently a substituent alkyl group with 1 or more but less than 10 carbon atoms, and R2 to R5 are each independently an alkyl group, an aryl group, or an alkoxy group, and each can be substituent alkyl group.]

[0010] Thus, if the bis(phosphine oxide) compound represented by the above formula (1) is included as a phosphorus-based flame retardant, the flame retardancy of the flame-retardant thermoplastic resin composition can be improved while its moisture resistance is enhanced.

[0011] Furthermore, in this invention, the phrase "may also have substituents" means "either without substitution or with substituents".

[0012] Therefore, it is preferable that the flame-retardant thermoplastic resin composition of the present invention has R2 to R5 as aryl groups that may also have substituents. If R2 to R5 in formula (1) are bis(phosphine oxide) compounds that may also have substituents, the flame retardancy and moisture resistance of the flame-retardant thermoplastic resin composition can be further improved.

[0013] Furthermore, the flame-retardant thermoplastic resin composition of the present invention preferably contains 17.5 parts by weight or less of the aforementioned bis(phosphine oxide) compound per 100 parts by weight of the aforementioned thermoplastic resin. If the content of the bis(phosphine oxide) compound is below the aforementioned upper limit, a flame-retardant thermoplastic resin composition that can further improve moisture resistance and fully utilize the physical properties of the thermoplastic resin (e.g., low moisture absorption, insulation, impact resistance, etc.) can be obtained.

[0014] Furthermore, the flame-retardant thermoplastic resin composition of the present invention is preferably a polyolefin resin—especially a cyclic olefin ring-opening polymer hydrogenation—as described above. This is because polyolefin resins—especially cyclic olefin ring-opening polymer hydrogenations—are materials with low environmental impact and excellent formability.

[0015] Furthermore, the flame-retardant thermoplastic resin composition of the present invention preferably uses a crystalline thermoplastic resin. Using a crystalline thermoplastic resin yields a flame-retardant thermoplastic resin composition with excellent chemical resistance and heat resistance. Moreover, using a crystalline thermoplastic resin allows for sufficient improvement in heat resistance even in small amounts of the bis(phosphine oxide) compound.

[0016] Furthermore, in this invention, the term "crystallization" of thermoplastic resin means that the crystallization temperature is detected in the form of an exothermic peak within a temperature range above the glass transition point and below the melting point by differential scanning calorimetry (DSC) according to JIS K7121.

[0017] Furthermore, this invention aims to successfully solve the aforementioned problems. The molded article of this invention is characterized by being formed from any of the flame-retardant thermoplastic resin compositions described above. If the flame-retardant thermoplastic resin composition described above is used, a molded article with excellent flame retardancy and moisture resistance can be obtained.

[0018] Moreover, this invention aims to successfully solve the aforementioned problems. The extended film of this invention is characterized by being formed using any of the flame-retardant thermoplastic resin compositions described above. If the flame-retardant thermoplastic resin composition described above is used, an extended film with excellent flame retardancy and moisture resistance can be obtained.

[0019] According to the present invention, a flame-retardant thermoplastic resin composition can be provided that improves both flame retardancy and moisture resistance.

[0020] Furthermore, according to the present invention, molded articles with excellent flame retardancy and moisture resistance, as well as extended films with excellent flame retardancy and moisture resistance, can be provided. Simple Explanation of the Diagram

[0021] none. Implementation

[0022] The following details the embodiments of the present invention.

[0023] Therefore, the flame-retardant thermoplastic resin composition of the present invention is not particularly limited and can be used as a material for, for example, the molded articles or extended films of the present invention. Furthermore, the extended films of the present invention are not particularly limited and can be suitably used, for example, as substrates for flexible flat cables.

[0024] (Flame-retardant thermoplastic resin composition)

[0025] The flame-retardant thermoplastic resin composition of the present invention comprises a thermoplastic resin and a specified bis(phosphine oxide) compound, and optionally further comprises other components such as additives. Furthermore, because the flame-retardant thermoplastic resin composition of the present invention contains the specified bis(phosphine oxide) compound, it exhibits excellent flame retardancy and moisture resistance.

[0026] <Thermoplastic resin>

[0027] Thermoplastic resin is the resin component that forms the base material of flame-retardant thermoplastic resin compositions. Moreover, the thermoplastic resin that forms the base material of flame-retardant thermoplastic resin compositions is generally flammable. The flammability rating of the thermoplastic resin itself according to the UL-94VTM specification is not particularly limited, but it may be "outside the specification".

[0028] Therefore, there are no particular limitations on thermoplastic resins, and examples include: polyethylene resins, polypropylene resins, polymethylpentene resins, cyclic olefin polymers (cyclic olefin addition polymers, cyclic olefin ring-opening polymers), cyclic olefin polymer hydrides, and other polyolefin resins; polyester resins such as polyethylene terephthalate and polybutylene terephthalate; polystyrene resins; polycarbonate resins; acrylonitrile-butadiene-styrene copolymers (ABS resin); etc. Among these, from the perspective of low environmental impact and good formability, polyolefin resins are preferred, cyclic olefin polymers or cyclic olefin polymer hydrides are even better, and from the perspective of excellent properties such as low moisture absorption, insulation, and impact resistance, cyclic olefin ring-opening polymer hydrides are particularly preferred.

[0029] In addition, thermoplastic resins can be used alone or in combination of two or more.

[0030] Furthermore, cyclic olefin ring-opening polymer hydrides suitable as thermoplastic resins can be obtained by further hydrogenating cyclic olefin ring-opening polymers obtained by ring-opening polymerization of cyclic olefins as monomers.

[0031] Therefore, as a cyclic olefin used in the preparation of ring-opening polymers of cyclic olefins, compounds having an alicyclic structure within the molecule and a carbon-carbon double bond within that alicyclic structure can be used. Monomers having a norethene ring structure (hereinafter referred to as "norethene monomers") can be used appropriately. Furthermore, a single cyclic olefin can be used alone, or two or more can be used in combination.

[0032] As a norethene monomer, it is appropriate to use the following formula: 『Transformation 2』 The compound shown. In this formula, R9, R10, R11, and R12 each independently represent a hydrogen atom; a halogen atom; a hydrocarbon group having 1 or more but less than 20 carbon atoms, and may also include a substituent comprising at least one of the group consisting of silicon, oxygen, and nitrogen atoms. Furthermore, two groups selected from R9, R10, R11, and R12 may be bonded to form a ring (e.g., a monocyclic or fused ring, and may be aromatic or non-aromatic). Moreover, in the formula, m represents 0, 1, or 2.

[0033] Examples of halogen atoms that are R9 to R12 include fluorine, chlorine, and bromine atoms.

[0034] Examples of hydrocarbon groups with 1 to 20 carbon atoms in the R9 to R12 range include: alkyl groups such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, dibutyl, tert-butyl, n-pentyl, isopentyl, n-hexyl, n-heptyl, n-octyl, n-nonyl, and n-decyl; cycloalkyl groups such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, and cycloheptyl; alkenyl groups such as vinyl, 1-propynyl, allyl, 1-butenyl, 2-butenyl, pentenyl, hexenyl, and cyclohexenyl; alkynyl groups such as ethynyl, 1-propynyl, 2-propynyl (propynyl), 3-butynyl, pentynyl, and hexynyl; aryl groups such as phenyl, tolyl, xylylyl, biphenyl, 1-naphthyl, 2-naphthyl, anthracene, and phenanthrene; aralkyl groups such as benzyl and phenethyl; and alkylene groups such as methylene, ethylene, and propylene. Furthermore, examples of substituents that can be arbitrarily present in a hydrocarbon group having 1 or more and 20 or fewer carbon atoms include halogen atoms such as fluorine and chlorine atoms; and alkoxy groups such as methoxy and ethoxy. In addition, the hydrocarbon group having 1 or more and 20 or fewer carbon atoms may have only one such substituent or may have two or more such substituents.

[0035] R9 to R12 includes at least one of the substituents selected from the group consisting of silicon, oxygen and nitrogen atoms, and examples include: silyl (trimethylsilyl, triethylsilyl, tributyldimethylsilyl, triisopropylsilyl, etc.), sulfonyl, hydroxyl, carbonyl, nitro, amino, imino, cyano, azo, and azido.

[0036] Furthermore, two groups from R9 to R12 (e.g., R9 and R10, R11 and R12, R9 and R11) can also combine to form a ring. The ring formed by two groups from R9 to R12 can be a monocyclic or a fused ring, and can be an aromatic or a non-aromatic ring.

[0037] Specific examples of norethene monomers include: Bicyclic [2.2.1]hept-2-ene (common name: norethene), 5-ethylidene bicyclic [2.2.1]hept-2-ene (common name: ethylidene norethene), and their derivatives (referring to those with substituents on the ring; the same applies below) and other bicyclic monomers; Tricyclic monomers such as [4.3.0 1,6.1 2,5]dec-3,7-diene (common name: dicyclopentadiene) and its derivatives; 7,8-Benzotricyclo[4.3.0.1 2,5]dec-3-ene (common name: methyl-bridged tetrahydrofuran; also known as 1,4-methyl-bridged-1,4,4a,9a-tetrahydrofuran), tetracyclic[4.4.0.1 2,5.1 7,10]dodecyl-3-ene (common name: tetracyclic dodecylene), 8-ethylenetetracyclic[4.4.0.1 2,5.1 7,10]-3-dodecylene and their derivatives, etc., are tetracyclic monomers.

[0038] Furthermore, examples of substituents that can be arbitrarily present on the ring of these norethene monomers include R9 to R12. Norethene monomers may have only one such substituent or may have two or more.

[0039] Furthermore, norethene monomers can be used alone or in combination of two or more. Among these, dicyclopentadiene and its derivatives are preferred, with dicyclopentadiene being the most desirable.

[0040] The amount of dicyclopentadiene used relative to the total amount of the cyclic olefin used in the preparation of the cyclic olefin ring-opening polymer is 100% by mass, preferably 50% by mass or more, preferably 80% by mass or more, and preferably 100% by mass or more.

[0041] Therefore, the cyclic olefin ring-opening polymer can also be a copolymer obtained by using the aforementioned norolefin monomers and a monocyclic cyclic olefin that may also have substituents.

[0042] Examples of monocyclic cyclic alkenes include monocyclic cyclic monoolefins such as cyclobutene, cyclopentene, cyclohexene, cycloheptene, and cyclooctene, and their derivatives; and monocyclic cyclic dienes such as cyclohexadiene and cyclooctadiene, and their derivatives. Furthermore, examples of substituents that monocyclic cyclic alkenes may include alkyl groups such as methyl and ethyl; alkenyl groups such as vinyl; alkylene groups such as propionyl-2-alkylene; aryl groups such as phenyl; hydroxyl groups; anhydride groups; carboxyl groups; and alkoxycarbonyl groups such as methoxycarbonyl. In addition, monocyclic cyclic alkenes may have only one type of such substituent or may have two or more types.

[0043] Furthermore, monocyclic cyclic alkenes with substituents can be used alone or in combination of two or more.

[0044] Furthermore, the amount of monocyclic cyclic olefins with substituents that can be used is not particularly limited, but the amount of the total cyclic olefin used in the preparation of the cyclic olefin ring-opening polymer is preferably 20% by mass or less, preferably 10% by mass or less, and preferably 0% by mass (that is, the cyclic olefin ring-opening polymer is a polymer obtained by using only one or two or more northoene monomers as monomers).

[0045] The preparation method of cyclic olefin ring-opening polymers is not particularly limited, and known methods, such as ring-opening polymerization of the monomers described above using metathesis polymerization catalysts, can be used. For example, the method described in Japanese Patent Publication No. 2017-149898 can be cited as such a method.

[0046] Furthermore, the weight average molecular weight (Mw) of the cyclic olefin ring-opening polymer obtained as described above is not particularly limited, but from the viewpoint of improving the mechanical properties (tensile strength, etc.) of the obtained molded articles or extended films, it is preferable to have a weight average of 15,000 or more and 150,000 or less, more preferably 20,000 or more and 100,000 or less, and even more preferably 23,000 or more and 50,000 or less.

[0047] The molecular weight distribution (Mw / Mn) of cyclic olefin ring-opening polymers is not particularly limited, but from the viewpoint of improving the mechanical properties (tensile strength, etc.) of the obtained molded articles or extended films, a value of 1 or more and 5 or less is preferred, and a value of 1 or more and 4 or less is even better.

[0048] Furthermore, in this invention, the "weight average molecular weight (Mw)" and "number average molecular weight (Mn)" of polymers such as cyclic olefin ring-opening polymers refer to the standard polystyrene conversion values ​​obtained using gel permeation chromatography (GPC) with tetrahydrofuran as the solvent.

[0049] By subjecting the cyclic olefin ring-opening polymer obtained as described above to a hydrogenation reaction, a cyclic olefin ring-opening polymer hydride can be obtained. The method for hydrogenating the cyclic olefin ring-opening polymer is not particularly limited, and known methods, such as supplying hydrogen within the reaction system in the presence of a hydrogenation catalyst, can be employed. Examples of such methods include, for instance, the method described in Japanese Patent Publication No. 2017-149898.

[0050] Furthermore, the hydrogenation rate (the proportion of carbon-carbon double bonds in the main chain after hydrogenation) in the hydrogenation reaction is not particularly limited, but 70% or higher is preferred, 80% or higher is better, 90% or higher is even better, and 99% or higher is especially desirable. A higher hydrogenation rate generally improves the heat resistance of the obtained cyclic olefin ring-opening polymer hydride.

[0051] Furthermore, in this invention, the "hydrogenation rate" in the hydrogenation reaction can be measured using nuclear magnetic resonance (NMR).

[0052] The weight average molecular weight (Mw) of the cyclic olefin ring-opening polymer hydride obtained as described above is not particularly limited, but from the viewpoint of improving the mechanical properties (tensile strength, etc.) of the obtained molded articles or extended films, it is preferable to have a weight average molecular weight of 15,000 or more, preferably 20,000 or more, even more preferably 23,000 or more, and preferably 150,000 or less, even more preferably 100,000 or less, and even more preferably 50,000 or less.

[0053] The molecular weight distribution (Mw / Mn) of cyclic olefin ring-opening polymer hydrides is not particularly limited, but from the viewpoint of improving the mechanical properties (tensile strength, etc.) of the obtained molded articles or extended films, a value of 1 or more and 5 or less is preferred, and a value of 1 or more and 4 or less is even better.

[0054] Furthermore, thermoplastic resins such as cyclic olefin ring-opening polymer hydrides are preferably crystalline. Using crystalline thermoplastic resins yields flame-retardant thermoplastic resin compositions with excellent chemical resistance and heat resistance. Moreover, using crystalline thermoplastic resins allows for significant improvement in heat resistance even with small amounts of bis(phosphine oxide) compounds.

[0055] Furthermore, in crystalline thermoplastic resins, the melting point temperature range is not particularly limited, but above 200°C is preferred, above 230°C is even better, and below 290°C is preferable. Thermoplastic resins with melting points within the above ranges are excellent due to their balance between formability and heat resistance.

[0056] Furthermore, in this invention, the melting point of the thermoplastic resin can be measured using the methods described in the embodiments of this specification.

[0057] Therefore, among crystalline thermoplastic resins, the thermoplastic resin used as the flame-retardant thermoplastic resin composition of the present invention is preferably a crystalline cyclic olefin ring-opening polymer hydrogenation. Furthermore, the crystalline cyclic olefin ring-opening polymer hydrogenation is not particularly limited, and those described in, for example, International Patent Publication No. 2012 / 033076, Japanese Patent Publication No. 2002-249553, and Japanese Patent Publication No. 2007-16102 can be used. Moreover, examples of crystalline cyclic olefin ring-opening polymer hydrogenations include dicyclopentadiene ring-opening polymer hydrogenations with anti-stereoregularity or homo-stereoregularity; however, from the viewpoint of productivity, dicyclopentadiene ring-opening polymer hydrogenations with anti-stereoregularity are preferred as the thermoplastic resin.

[0058] Furthermore, dicyclopentadiene ring-opening polymer hydrides with anti-stereoregularity can be suitably synthesized, for example, by following the method disclosed in Japanese Patent Publication No. 2017-170735.

[0059] <Diphosphine oxide compounds>

[0060] The flame-retardant thermoplastic resin composition of the present invention contains the following formula (1): 『Transformation 3』 [In formula (1), R1 can be a substituent alkyl group, a substituent aryl group, or a divalent organogroup represented by formula: -Q1-Ar-Q2-[where Ar can be a substituent aryl group, Q1 and Q2 are each independently a substituent alkyl group with 1 or more but less than 10 carbon atoms, and R2 to R5 are each independently an alkyl group, an aryl group, or an alkoxy group, and each can be substituent alkyl group.] The indicated bis(phosphine oxide) compound is used as a phosphorus-based flame retardant.

[0061] When the aforementioned bis(phosphine oxide) compound is used, flame-retardant thermoplastic resin compositions with excellent flame retardancy and moisture resistance can be obtained. Furthermore, the aforementioned bis(phosphine oxide) compound is also excellent in terms of low environmental impact and further suppressing the decline of dielectric and other electrical properties of the resin composition.

[0062] Here, examples of alkyl groups that can also have substituents, as R 1, include methylene, ethyl, propyl, and butyl. Among these, alkyl groups with 1 or more carbon atoms and 4 or fewer carbon atoms are preferred, with methylene or ethyl being more preferred.

[0063] Furthermore, examples of aryl groups that can also have substituents, such as arylphenyl, arylbiphenyl, and arylnaphthyl, are possible. Among these, aryl groups with 6 or more carbon atoms and 18 or fewer are preferred, aryl groups with 6 or more carbon atoms and 12 or fewer are even more preferred, and arylphenyl, arylbiphenyl, or arylnaphthyl are even more preferred.

[0064] Furthermore, the substituents that can be "alkyl groups or aryl groups" in R 1 are not particularly limited, and examples include: nitro, cyano, hydroxyl, carboxyl, amino, alkoxy, etc.

[0065] Furthermore, examples of aryl groups representing Ar in divalent organogroups (-Q 1-Ar-Q 2-) include aryl groups such as arylphenyl, arylbiphenyl, and arylnaphthyl. Among these, aryl groups representing Ar are preferably those with 6 or more but less than 18 carbon atoms, and even more preferably those with 6 or more but less than 12 carbon atoms, with arylphenyl, arylbiphenyl, or arylnaphthyl being the most preferred.

[0066] Furthermore, examples of alkyl groups in divalent organogroups (-Q1-Ar-Q2-) that have 1 or more but less than 10 carbon atoms in Q1 and Q2 include methylene, ethyl, propyl, and butyl. Among these, alkyl groups with 1 or more but less than 10 carbon atoms are preferred, with methylene or ethyl being more advantageous.

[0067] Furthermore, Q1 and Q2 can be the same or different from each other, but it is better if they are the same.

[0068] Furthermore, there are no particular restrictions on the substituents that can be used for Ar, Q1, and Q2; examples include nitro, cyano, hydroxyl, carboxyl, amino, and alkoxy groups.

[0069] Of the above, R1 is preferably an aryl group or a divalent organogroup represented by the formula: -Q1-Ar-Q2-, which may also have substituents. It is more preferably an organogroup represented by the formula: -Q1-Ar-Q2-, which is phenyl, biphenyl, naphthyl, or Ar is phenyl, biphenyl, or naphthyl and is divalent. It is even more preferably an organogroup represented by the formula: -CH2-Ar-CH2-, which is phenyl and is divalent. It is particularly preferred an organogroup represented by the formula: -CH2-Ar-CH2-, which is phenyl.

[0070] Furthermore, examples of alkyl groups that are "substituents" among R2 to R5 include methyl, ethyl, propyl, and butyl. Among these, alkyl groups with 1 or more carbon atoms and 4 or fewer carbon atoms are preferred, with methyl or ethyl being more preferred.

[0071] Furthermore, examples of aryl groups that are "aryl groups that may also have substituents" among R2 to R5 include phenyl, biphenyl, and naphthyl. Among these, aryl groups with 6 or more carbon atoms and 18 or fewer are preferred, aryl groups with 6 or more carbon atoms and 12 or fewer are even more preferred, and phenyl, biphenyl, or naphthyl are even more preferred.

[0072] Furthermore, examples of alkoxy groups that are R2 to R5 and may also have substituents include methoxy, ethoxy, propoxy, and butoxy. Among these, alkoxy groups with 1 or more carbon atoms and 4 or fewer carbon atoms are preferred, with methoxy or ethoxy being more advantageous.

[0073] Furthermore, the substituents that can be "alkyl groups, aryl groups, or alkoxy groups" of R2 to R5 are not particularly limited, and examples include: nitro, cyano, hydroxyl, carboxyl, amino, alkoxy, etc.

[0074] Of the above, R2 to R5 are preferably aryl groups that can be independently substituted, with phenyl, biphenyl, or naphthyl groups being more preferred, and phenyl being even more preferred. Furthermore, R2 to R5 can be the same or different from each other, but it is preferred that they are all the same, and it is especially preferred that they are all phenyl.

[0075] Furthermore, the bis(phosphine oxide) compound is expressed by the following formula (1-1): 'Transformation 4' [In equation (1-1), R1 is the same as in equation (1).] The bis(diphenylphosphine oxide) compound represented is preferred, especially the bis(diphenylphosphine oxide) compound represented by the above formula (1-1) with an R1-based phenyl group or a divalent organogroup represented by the formula: -CH2-Ar-CH2- (where Ar is a phenyl, biphenyl, or naphthyl group). The bis(diphenylphosphine oxide) compound represented by the following formula is even more preferred. 'Transformation 5'

[0076] Furthermore, the amount of bis(phosphine oxide) compound in the flame-retardant thermoplastic resin composition is not particularly limited, but it is preferable to have 1 part by weight or more per 100 parts by weight of thermoplastic resin, more preferably 5 parts by weight or more, and preferably 30 parts by weight or less, more preferably 17.5 parts by weight or less, and even more preferably 10 parts by weight or less. If the content of the bis(phosphine oxide) compound is above or above the above-mentioned lower limit, the flame retardancy of the flame-retardant thermoplastic resin composition can be further improved. Moreover, if the content of the bis(phosphine oxide) compound is below the above-mentioned upper limit, the moisture resistance of the flame-retardant thermoplastic resin composition can be further improved, and a flame-retardant thermoplastic resin composition that fully utilizes the physical properties of thermoplastic resin (such as low moisture absorption, insulation, impact resistance, etc.) can be obtained.

[0077] <Other Ingredients>

[0078] The flame-retardant thermoplastic resin composition of this invention is not particularly limited as long as it does not impair the effects of this invention, and may contain any other components. Examples of such other components include various additives.

[0079] Specifically, examples of additives include: fillers, antioxidants, release agents, antibacterial agents, coupling agents, plasticizers, colorants, lubricants, silicone oils, foaming agents, surfactants, light stabilizers, dispersants, dispersing aids, heat stabilizers, ultraviolet absorbers, antistatic agents, nucleating agents, antifogging agents, neutralizing agents, decomposing agents, metal deactivators, antifouling materials, fibrous reinforcing materials (glass fiber, carbon fiber, synthetic fiber, ceramic fiber, whiskers), plate-like reinforcing materials (mica, talc, clay, glass flakes), and granular reinforcing materials (metal oxides, carbonates, sulfates, glass beads, carbon black). These additives can be used individually or in combination of two or more. Furthermore, the content of these additives is not particularly limited and can be appropriately determined according to the purpose of addition, without impairing the effects of the present invention.

[0080] Furthermore, other components that may be contained in the flame-retardant thermoplastic resin composition of the present invention may also include flame retardants or anti-drip agents other than the bis(phosphine oxide) compounds mentioned above.

[0081] Therefore, the so-called anti-drip agent is a compound that can inhibit the melting and dripping of resin components during combustion, thereby further improving flame retardancy. Examples include fluorinated resins. Specifically, examples of fluorinated resins include: polytetrafluoroethylene (PTFE), polyhexafluoropropylene (PTFE), (tetrafluoroethylene / hexafluoropropylene) copolymer, (tetrafluoroethylene / perfluoroalkyl vinyl ether) copolymer, (tetrafluoroethylene / ethylene) copolymer, (hexafluoropropylene / propylene) copolymer, polydifluoroethylene, and (difluoroethylene / ethylene) copolymer. Among these, PTFE, (tetrafluoroethylene / perfluoroalkyl vinyl ether) copolymer, (tetrafluoroethylene / hexafluoropropylene) copolymer, (tetrafluoroethylene / ethylene) copolymer, and polydifluoroethylene are preferred, with PTFE and (tetrafluoroethylene / ethylene) copolymer being the most desirable.

[0082] In addition, compounds used as anti-drip agents are generally flame-retardant. The flammability rating of the compounds used as anti-drip agents according to the UL-94 VTM specification is not particularly limited, but it is better to have a rating of "VTM-2" or higher, "VTM-1" or higher is better, and "VTM-0" is even better.

[0083] Moreover, the amount of anti-drip agent can be made into a mixture of more than 0.01 parts by weight and less than 1 part by weight per 100 parts by weight of thermoplastic resin.

[0084] <Preparation Method of Flame-Retardant Thermoplastic Resin Composition>

[0085] The flame-retardant thermoplastic resin composition of the present invention can be obtained by mixing the components described above. The specific preparation method is not particularly limited, but it is preferable to premix the thermoplastic resin and add a bis(phosphine oxide) compound to the premixed thermoplastic resin.

[0086] Furthermore, when using crystalline thermoplastic resins, from the viewpoint of obtaining a thoroughly mixed flame-retardant thermoplastic resin composition, mixing the thermoplastic resin in the molten state is preferable. When mixing in the molten state, it is preferable to mix at a temperature ranging from the glass transition temperature of the thermoplastic resin +50°C to +250°C. If the temperature is too low, the viscosity will increase, making mixing difficult; if the temperature is too high, the thermoplastic resin or other components will easily deteriorate.

[0087] After mixing, for example, the flame-retardant thermoplastic resin composition can be obtained by extruding it into rods in the molten state and cutting it into appropriate lengths using a wire cutter.

[0088] (formed body)

[0089] The molding system of the present invention is formed from the flame-retardant thermoplastic resin composition of the present invention as described above. It typically includes a thermoplastic resin and the aforementioned bis(phosphine oxide) compound, and optionally includes other components such as additives. Moreover, since the molded article of the present invention uses the aforementioned flame-retardant thermoplastic resin composition as the molding material, it exhibits excellent flame retardancy and moisture resistance.

[0090] Therefore, the shape of the molded body is not particularly limited and can be made into shapes such as thin films to suit different applications. Furthermore, the molding method of the flame-retardant thermoplastic resin composition is not particularly limited and can use known molding methods such as injection molding, extrusion molding, compression molding, blow molding, blow molding, burnishing molding, injection molding, and compression molding.

[0091] (Extended film)

[0092] The extended film of the present invention is formed using the flame-retardant thermoplastic resin composition of the present invention as described above, typically comprising a thermoplastic resin and the aforementioned bis(phosphine oxide) compound, and optionally further comprising additives and other components. Furthermore, because the extended film of the present invention uses the aforementioned flame-retardant thermoplastic resin composition as the molding material, it exhibits excellent flame retardancy and moisture resistance.

[0093] Therefore, the extended film can be obtained by extending the film obtained by molding the flame-retardant thermoplastic resin composition of the present invention, and arbitrarily subjecting it to post-treatment of thermoplastic resin crystallization and / or relaxation of the tension of the extended film.

[0094] Furthermore, there are no particular limitations on the stretching of the film, the crystallization of the thermoplastic resin, and the relaxation of the tension of the stretched film, and these can be carried out using, for example, the method described in Japanese Patent Publication No. 2021-107508.

[0095] Furthermore, the thickness of the stretched film can be set arbitrarily, but it is preferably 10 μm or more, and preferably 40 μm or less, with 30 μm or less being even better. If the thickness of the stretched film is below the above-mentioned upper limit, it exhibits excellent flexibility, thus allowing it to be used smoothly as a flexible substrate, etc. Furthermore, if the thickness is above the above-mentioned lower limit, it exhibits sufficiently excellent strength.

[0096] Example

[0097] The present invention will be described in detail below with reference to the embodiments, but the present invention is not limited to these embodiments.

[0098] Furthermore, in the examples and comparative examples, the glass transition temperature and melting point of the polymer, the molecular weight and molecular weight distribution of the polymer, the hydrogenation rate during polymer hydrogenation, and the flame retardancy, dielectric properties and moisture resistance of the film were measured and evaluated by the following methods.

[0099] <Glass Transfer Temperature and Melting Point>

[0100] Following JIS K7121, differential scanning calorimeter was used to perform differential scanning calorimetry at a heating rate of 10℃ / min to measure the glass transition temperature and melting point of the polymer.

[0101] <Molecular weight and molecular weight distribution>

[0102] Using tetrahydrofuran as the solvent, gel permeation chromatography (GPC) was performed at 40°C. The weight-average molecular weight (Mw) and number-average molecular weight (Mn) were calculated in polystyrene equivalent form, and the molecular weight distribution (Mw / Mn) was determined. Furthermore, the following were used as the measuring apparatus and column. Measurement Apparatus: Gel Permeation Chromatography (GPC) System "HLC-8220" (manufactured by Tosoh Corporation) Tubing: "H-type tubing" (manufactured by Tosoh Corporation)

[0103] <Hydrogenation rate>

[0104] The hydrogenation rate of unsaturated bonds in the polymer was determined by 1H-NMR measurement.

[0105] <Flame retardancy (UL-94VTM specification)>

[0106] The 100 μm thick film obtained in the examples and comparative examples was cut into strips 50 mm wide and 200 mm long using a cutter, and the strips rolled into cylinders were designated as test pieces. These test pieces were vertically fixed with clamps, and cotton was placed underneath them. The flame from the burner was brought into contact with the lower end of the test piece for 3 seconds, and then removed. The time from the flame igniting on the test piece to its extinguishing was measured. Next, while the flame was extinguished, a second contact with the flame was performed for 3 seconds, and the time from the flame igniting to its extinguishing was measured again, comparing it to the first operation. Furthermore, it was evaluated whether any embers falling during combustion would ignite the cotton placed underneath the test piece.

[0107] The evaluation was conducted using 5 samples, and the flammability rating was assigned according to the UL-94 VTM specification based on the burning time of the first and second burns, the sum of the burning times of the 5 samples, and the presence or absence of cotton ignition. The flammability ratings with the highest self-flammability were VTM-0, VTM-1, VTM-2, and out of specification (VTM-0 being the highest and out of specification being the lowest). Those with VTM-2 and above were rated "good", and those with VTM-out of specification were rated "poor".

[0108] <Dielectric Properties>

[0109] For the 100 μm thick thin film obtained in the examples and comparative examples, the dielectric constant and dielectric loss were measured by the balanced-type circular disk resonator method.

[0110] 〈Moisture resistance〉

[0111] The 100 μm thick film obtained in the examples and comparative examples was placed in a constant temperature and humidity bath at 85°C and 85%RH and left to stand for 2 weeks (humidity resistance test). Afterward, the film was removed from the constant temperature and humidity bath and its flame retardancy (UL-94VTM specification) and dielectric properties were evaluated and measured in accordance with the above operation.

[0112] The closer the evaluation after the moisture resistance test is to the evaluation under conditions where no moisture resistance test has been conducted, the better the moisture resistance.

[0113] (Manufacturing Example 1: A mixture containing crystalline cyclic olefin ring-opening polymer hydrides)

[0114] After drying, 154.5 parts by mass of cyclohexane, 42.8 parts by mass of a cyclohexane solution (70% by mass concentration) containing dicyclopentadiene (with an endogenous isomer content of ≥99% by mass) (30 parts by mass for dicyclopentadiene), and 1.9 parts by mass of 1-hexene were added to a metal pressure-resistant reaction vessel that had been purged with nitrogen. The contents were then heated to 53°C. Meanwhile, a catalyst solution was prepared by dissolving 0.014 parts by mass of tetrachlorophenylimine (tetrahydrofuran) tungsten complex in 0.70 parts by mass of toluene, adding 0.061 parts by mass of a hexane solution (19% by mass concentration) containing diethylaluminum ethoxide, and stirring for 10 minutes. This catalyst solution was added to the aforementioned reaction vessel, and a ring-opening polymerization reaction was carried out at 53°C for 4 hours to obtain a solution containing the dicyclopentadiene ring-opening polymer.

[0115] 0.037 parts by mass of 1,2-ethylene glycol were added to 200 parts by mass of the obtained solution containing the dicyclopentadiene ring-opening polymer as a terminator, and the polymerization reaction was terminated by stirring at 60°C for 1 hour. Then, 1 part by mass of a hydrotalcite compound (Kyowa Chemical Industry Co., Ltd., KYOWAAD 2000, registered trademark) acting as an adsorbent was added, and the mixture was heated to 60°C and stirred for 1 hour. 0.4 parts by mass of a filter aid (Showa Chemical Industry Co., Ltd., Radiolite #1500, registered trademark) was added, and the adsorbent was filtered out using a PP pleated filter (ADVANTEC Toyo Co., Ltd., TCP-HX) to obtain a solution containing the dicyclopentadiene ring-opening polymer. The molecular weight of the dicyclopentadiene ring-opening polymer was measured using a portion of this solution, and the weight-average molecular weight (Mw) was 28,100, and the molecular weight distribution (Mw / Mn) was 3.21.

[0116] 200 parts by mass of the obtained solution containing the dicyclopentadiene ring-opening polymer (polymer content 30 parts by mass) were mixed with 100 parts by mass of cyclohexane and 0.0043 parts by mass of a ruthenium hydrochloride carbonyl triphenylphosphine (TPMT) zeolite as a hydrogenation catalyst. The mixture was subjected to hydrogenation at 6 MPa and 180°C for 4 hours. The reaction solution was a slurry with solid components. The solid components were separated from the solution by centrifugation. While stirring with a stirrer, 0.1 parts by mass of tetra{3-[3,5-di(tributyl)-4-hydroxyphenyl]propionic acid}neopentetrol ester was added to the solid components as an antioxidant. The mixture was then dried under reduced pressure at 60°C for 24 hours to obtain a mixture of the cyclic olefin (dicyclopentadiene) ring-opening polymer hydride and the antioxidant. The hydrogenation rate in the hydrogenation reaction was above 99%, and the glass transition temperature of the obtained cyclic olefin ring-opening polymer hydride was 98°C, and the melting point was 262°C.

[0117] (Manufacturing Example 2: A mixture containing amorphous cyclic olefin ring-opening polymer hydrides)

[0118] After drying, in a reaction vessel equipped with a stirrer and internally purged with nitrogen, 300 parts by mass of cyclohexane, 0.5 parts by mass of 1-hexene, 0.15 parts by mass of dibutyl ether, and 1.5 parts by mass of a 10% cyclohexane solution of triisobutylaluminum (0.15 parts by mass for triisobutylaluminum) were added. The contents were then heated to 40°C. Subsequently, while stirring the contents and maintaining the temperature at 40°C, a mixture of 70 parts by mass of tetracyclododecene and 30 parts by mass of dicyclopentadiene, along with 11 parts by mass of a 0.6% cyclohexane solution of tungsten hexachloride (0.066 parts by mass for tungsten hexachloride), were continuously added to carry out the polymerization reaction. A solution containing a ring-opening copolymer (cyclic olefin ring-opening polymer) of tetracyclododecene and dicyclopentadiene was then obtained. Add 0.5 parts by mass of butyl glycidyl ether and 0.2 parts by mass of isopropanol to this solution as a terminator, and stir at 40°C for 1 hour to terminate the polymerization reaction.

[0119] Using a portion of the obtained polymerization reaction solution, the molecular weight of the cyclic olefin ring-opening polymer was measured. The weight-average molecular weight (Mw) was 42,000, and the molecular weight distribution (Mw / Mn) was 2.30.

[0120] 100 parts by mass of cyclohexane and 4 parts by mass of diatomaceous earth-supported nickel catalyst (T8400RL, nickel loading rate 57%, manufactured by Süd-Chemie Catalyst Co., Ltd.) were added to 200 parts by mass of the obtained polymerization reaction solution (polymer content 30 parts by mass). The reaction was carried out at a hydrogen pressure of 4.5 MPa and a temperature of 170°C for 5 hours. Subsequently, after filtering the reaction solution to remove the hydrogenation catalyst, 0.1 parts by mass of tetra{3-[3,5-di(tributyl)-4-hydroxyphenyl]propionic acid}neopentyl tetraol ester was added to the filtrate as an antioxidant. Using a thin-film evaporator (Buss Co., Ltd., film truder), the volatile components were evaporated from the solution at a temperature of 260°C (533°K), a pressure below 1 kPa, and a residence time of 1.2 hours, to obtain a mixture of tetracyclododecene-dicyclopentadiene cyclic olefin ring-opening polymer hydride and antioxidant.

[0121] The hydrogenation rate in the hydrogenation reaction was over 99%. Furthermore, the glass transition temperature of the obtained cyclic olefin ring-opening polymer hydride was 142°C. Additionally, no melting point was observed.

[0122] (Preparation of flame retardant)

[0123] Prepare the following phosphorus-based flame retardants.

[0124] <Diphosphine oxide compounds>

[0125] The following formula shows the derivative of p-xylylbis(diphenylphosphine oxide) (manufactured by Jin Yi Chemical Co., Ltd., PQ-60). 'Transformation 6'

[0126] <Organic hypophosphite flame retardants>

[0127] [Organic hypophosphite flame retardant (1)]

[0128] Aluminum triethylphosphite (manufactured by Clariant Chemicals, Inc., Exolit (registered trademark) OP935) as shown in formula (V) 'Transformation 7'

[0129] [Organic hypophosphite flame retardant (2)]

[0130] The aluminum triethylphosphite (manufactured by Clariant Chemicals Inc., Exolit (registered trademark) OP945, with a particle size smaller than that of the above-mentioned organic hypophosphite flame retardant (1), as shown in formula (V) above)

[0131] (Example 1)

[0132] <Preparation of Molding Materials>

[0133] 100.33 parts by mass of the mixture obtained in Manufacturing Example 1 (100 parts by mass of the crystalline cyclic olefin ring-opening polymer hydride) and 10 parts by mass of p-xylylbis(diphenylphosphine oxide) (PQ-60) as a phosphorus-based flame retardant were mixed in a biaxial mixing extruder (Toshiba Machine Co., Ltd., TEM-37BS) to obtain a strand (rod-shaped molten resin). The obtained strand was cut using a wire cutter to obtain granular molding material (flame-retardant thermoplastic resin composition). The operating conditions of the biaxial mixing extruder are disclosed below. • Material tank set temperature: 270~290℃ Screw speed: 200 rpm Screw diameter: 37 mm ·L / D:50

[0134] In addition, phosphorus-based flame retardants are added to the cyclic olefin ring-opening polymer hydride in the compounding process using the side feeder of a biaxial compounding extruder (side feeder; that is, the cyclic olefin ring-opening polymer hydride is premixed, and the phosphorus-based flame retardant is added to the premixed cyclic olefin ring-opening polymer hydride).

[0135] <Thin Film Manufacturing>

[0136] The granular molding material obtained as described above is used to form a film (molded body) using a film extruder (manufactured by GSI Corporation, a T-mode film melt extrusion molding machine of hanger manifold type with a screw diameter of 20 mm, compression ratio of 3.1, and L / D=30) to obtain a film (molded body) with a thickness of 100 μm.

[0137] The flame retardancy, dielectric properties, and moisture resistance of the obtained films were then evaluated. The results are shown in Table 1.

[0138] (Examples 2-3)

[0139] Except that the amount of p-xylylbis(diphenylphosphine oxide) (PQ-60) used as a phosphorus-based flame retardant was prepared as 15 parts by weight (Example 2) and 20 parts by weight (Example 3), the preparation of the molding material and the manufacture of the film were carried out in accordance with Example 1. Then, the evaluation was carried out in accordance with Example 1. The results are shown in Table 1.

[0140] (Example 4)

[0141] Except that the mixture obtained in Manufacturing Example 2 was used in place of the mixture containing crystalline cyclic olefin ring-opening polymer hydride in Manufacturing Example 1, with 100 parts by mass of amorphous cyclic olefin ring-opening polymer hydride used instead of the mixture containing crystalline cyclic olefin ring-opening polymer hydride obtained in Manufacturing Example 1, the preparation of the molding material and the manufacture of the film were carried out in accordance with Example 1. Then, the evaluation was carried out in accordance with Example 1. The results are shown in Table 1.

[0142] (Examples 5-6)

[0143] Except that the amount of p-xylylbis(diphenylphosphine oxide) (PQ-60) used as a phosphorus-based flame retardant was prepared as 17.5 parts by weight (Example 5) and 5 parts by weight (Example 6), the preparation of the molding material and the fabrication of the film were carried out in accordance with Example 1. Then, the evaluation was carried out in accordance with Example 1. The results are shown in Table 1.

[0144] (Comparative Example 1)

[0145] Except for the absence of phosphorus-based flame retardants, the preparation of the molding material and the fabrication of the film were carried out in accordance with Example 1. Then, the process was evaluated in accordance with Example 1. The results are shown in Table 1.

[0146] (Comparative Example 2)

[0147] Except for using 10 parts by weight of aluminum triethylphosphite (Exolit (registered trademark) OP935), an organophosphite flame retardant (1), instead of p-xylylbis(diphenylphosphine oxide) (PQ-60) as a phosphorus-based flame retardant, the preparation of the molding material and the manufacture of the film were carried out in accordance with Example 1. Then, the process was evaluated in accordance with Example 1. The results are shown in Table 1.

[0148] (Comparative Example 3)

[0149] Except for using 10 parts by mass of aluminum triethylphosphite (Exolit (registered trademark) OP945), an organophosphite flame retardant (2), instead of p-xylylbis(diphenylphosphine oxide) (PQ-60) as a phosphorus-based flame retardant, the preparation of the molding material and the manufacture of the film were carried out in accordance with Example 1. Then, the process was evaluated in accordance with Example 1. The results are shown in Table 1.

[0150] (Compare Examples 4 and 5)

[0151] Except that the amount of phosphorus-based flame retardant incorporated was 20 parts by weight, the preparation of the molding material and the fabrication of the film were carried out in accordance with Comparative Example 2 and Comparative Example 3, respectively. Then, the process was evaluated in accordance with Example 1. The results are shown in Table 1.

[0152] Table 1 Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 thermoplastic resin Crystalline cyclic olefin ring-opening polymer hydrides [parts by weight] 100 100 100 - 100 100 100 100 100 100 100 Amorphous cyclic olefin ring-opening polymer hydrides [parts by weight] - - - 100 - - - - - - - antioxidants Neopentyl tetramethyl 3-[3,5-di(tributyl)-4-hydroxyphenyl]propionic acid [parts by weight] 0.33 0.33 0.33 0.33 0.33 0.33 0.33 0.33 0.33 0.33 0.33 Phosphorus-based flame retardants Bis(phosphine oxide) compounds PQ-60 [Quantity] 10 15 20 10 17.5 5 - - - - - Organic hypophosphite flame retardants (1) OP935 [Quantity] - - - - - - - 10 - 20 - Organic hypophosphite flame retardants (2) OP945 [Quantity] - - - - - - - - 10 - 20 evaluate Flame retardancy good good good good good good bad bad bad good good Dielectric properties Dielectric constant Dk @10GHz 2.1 2.2 2.1 2.1 2.1 2.1 2.1 2.1 2.1 2.2 2.2 Dielectric loss Df @10GHz 0.0006 0.0007 0.0007 0.0006 0.0007 0.0006 0.0006 0.0009 0.0009 0.0012 0.0012 Moisture resistance Flame retardancy good good good good good good bad bad bad bad bad Dielectric properties Dielectric constant Dk @10 GHz 2.1 2.2 2.1 2.1 2.1 2.1 2.1 2.1 2.1 2.2 2.2 Dielectric loss Df @10 GHz 0.0006 0.0007 0.0008 0.0006 0.0007 0.0006 0.0006 0.0010 0.0010 0.0013 0.0013

[0153] As shown in Table 1, in Examples 1-6 using bis(phosphine oxide) compounds as phosphorus-based flame retardants, compared with Comparative Example 1 without phosphorus-based flame retardants and Comparative Examples 2-5 using organic hypophosphite-based flame retardants as phosphorus-based flame retardants, molded articles with excellent flame retardancy and moisture resistance can be obtained.

[0154] According to the present invention, a flame-retardant thermoplastic resin composition can be provided that improves both flame retardancy and moisture resistance.

[0155] Furthermore, according to the present invention, molded articles with excellent flame retardancy and moisture resistance, as well as extended films with excellent flame retardancy and moisture resistance, can be provided.

[0156] none

Claims

1. A flame-retardant thermoplastic resin composition comprising a thermoplastic resin and a bis(phosphine oxide) compound represented by the following formula (1): 『Chemical Formula 1』 [In formula (1), R1 is an alkylene group which may have a substituent, an arylene group which may have a substituent, or a divalent organic group represented by the formula: -Q1-Ar-Q2- [wherein, Ar is an arylene group which may have a substituent, and Q1 and Q2 are each independently an alkylene group having 1 or more and 10 or less carbon atoms which may have a substituent]], and R2 to R5 are each independently an alkyl group which may have a substituent, an aryl group which may have a substituent, or an alkoxy group which may have a substituent], wherein the thermoplastic resin is a hydrogenated cyclic olefin ring-opening polymer.

2. The flame-retardant thermoplastic resin composition according to claim 1, wherein R2 to R5 are each independently an aryl group which may have a substituent.

3. The flame-retardant thermoplastic resin composition according to claim 1, wherein the content of the bis(phosphine oxide) compound is 17.5 parts by mass or less per 100 parts by mass of the thermoplastic resin.

4. The flame-retardant thermoplastic resin composition according to any one of claims 1 to 3, wherein the thermoplastic resin has crystallinity.

5. A molded article formed from the flame-retardant thermoplastic resin composition according to any one of claims 1 to 4.

6. A stretched film formed using the flame-retardant thermoplastic resin composition according to any one of claims 1 to 4.