JP3361616B2 - Polyolefin-based flame-retardant crosslinkable resin composition - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polyolefin-based flame-retardant crosslinkable resin composition. 2. Description of the Related Art Polyolefin resins are crosslinked by a method such as addition of a peroxide and electron beam irradiation in order to impart mechanical strength and heat resistance. Widely used as tubes and the like. [0003] Such polyolefin resins are inherently easily combustible (flammable) resins. However, with the expansion of applications in recent years, the demand for flame retardancy has increased, and the polyolefin resins have been hardened by various methods. Combustion is being considered. As described above, by cross-linking the polyolefin-based resin, the mechanical strength, heat resistance, and the like are improved, and some flame retardancy is recognized. However, it is still flammable. As a general method for making a polyolefin resin flame-retardant, a method of adding a halogen-containing compound has been used. The method of adding the halogen-containing compound can impart a high degree of flame retardancy to the polyolefin resin, but generates a large amount of corrosive gas due to the halogen-containing compound at the time of secondary processing or combustion, Problems such as toxicity to the human body and corrosiveness to equipment have arisen. In order to cope with the above problems, there is a strong demand for a safe flame-retarding method for a polyolefin-based resin without using a halogen-containing compound. Various methods for flame retarding polyolefin resins without the use of the above halogen-containing compounds have also been studied. For example, hydrated alumina treated with a titanate coupling agent is added to a low crystalline ethylene copolymer. Low-flammable flame-retardant polyolefin composition (JP-A-57-165437) obtained by adding a hydrated metal oxide such as basic magnesium carbonate, zinc borate, zinc carbonate, etc .; An inorganic flame retardant such as aluminum hydroxide, basic magnesium carbonate, magnesium hydroxide, or hydrotalcite is used in an amount of 50 to 100 parts by weight of the blend of -α-polyolefin.
Flame retardant electrical insulation composition containing 300 parts by weight
No. 1-36363), a flame-retardant additive such as ammonium polyphosphate and chopped reinforcing fibers are used for a high-impact thermoplastic base polymer containing no halogen and a substance that forms cyanide on burning. A flame-retardant and high-impact polyethylene molding composition (JP-A-3-217456) containing a predetermined amount has been proposed. [0006] However, in the case of the above or the proposed method, in order to impart sufficient flame retardancy to the polyolefin resin, it is necessary to add a large amount of a hydrated metal oxide or an inorganic flame retardant. As a result, there are problems in that the secondary workability of the polyolefin-based resin composition becomes difficult and the quality of the secondary processed product is reduced. Further, in the case of the method proposed above, there is a problem that a practically effective flame retarding effect cannot be obtained by adding only a flame retardant additive such as ammonium polyphosphate. As described above, a method for sufficiently flame-retarding a polyolefin-based resin without using a halogen-containing compound and without lowering the secondary processability or the quality of the secondary processed product has not yet been established. It is a reality. SUMMARY OF THE INVENTION The present invention solves the above-mentioned conventional problems by expressing excellent flame retardancy without using a halogen-containing compound, and at the same time, improving the secondary workability and the secondary workability. An object of the present invention is to provide a polyolefin-based flame-retardant crosslinkable resin composition which is excellent in the quality of the next processed product. [0008] The polyolefin-based flame-retardant crosslinkable resin composition of the present invention is based on 100 parts by weight of a polyolefin-based resin and is based on melamine and tris (1,2-diphenyl).
Droxyethyl) isocyanurate, 1,3,5-tri
(2-hydroxyethyl) cyanurate and triali
At least one selected from luisocyanurates
Made by phosphorus-containing compounds 1 to 50 parts by weight represented by the nitrogen-containing compound 0.5 to 30 parts by weight and the following formula (1) are contained, the total content of the above nitrogen-containing compound and a phosphorus-containing compound is 5 It is characterized in that it is not less than parts by weight, thereby achieving the above object. Embedded image (In the formula, at _{least two of} R ₁ , R ₂ and R ₃ represent the following general formulas (a) or (b), and others represent a hydrogen atom, a hydroxyl group, or a linear or branched alkyl group having 20 or less carbon atoms. , Carbon number 2
Represents a linear or branched alkoxyl group, aryl group or aryloxyl group of 0 or less. [In the formulas (a) and (b), R ₄ and R ₆ represent a hydrogen atom or a methyl group, and R ₅ represents a linear or alkyl group having 30 or less carbon atoms.] The type of polyolefin-based resin used in the flame-retardant cross-linkable resin composition (hereinafter, referred to as “polyolefin-based resin composition”) is not particularly limited, but may be polypropylene-based resin, polyethylene-based resin, or polyolefin-based resin. (1-butene) -based resins, polypentene-based resins, and the like, and one or more of these resins are suitably used. The polypropylene resin may be not only a polypropylene homopolymer but also a copolymer containing propylene as a main component and a mixture thereof. The copolymer containing propylene as a main component is not particularly limited, but propylene and ethylene, 1-
Hexene, 4-methyl-1-pentene, 1-octene,
Copolymers with α-olefins such as 1-butene and 1-pentene are exemplified, and one or more of these are suitably used. The polyethylene resin may be not only a polyethylene homopolymer but also a copolymer containing ethylene as a main component or a mixture thereof. The copolymer containing ethylene as a main component is not particularly limited, but ethylene and propylene, 1-hexene, 4-methyl-1-pentene, 1-octene, 1-
Butenes, copolymers of α-olefins such as 1-pentene, copolymers of ethylene and vinyl acetate, copolymers of ethylene and ethyl acrylate, and one or more of these are preferred. Used for [0012] As the type of the nitrogen-containing compound used in the polyolefin resin composition according to the present invention preferably has a decomposition temperature of that is close to the melting point of the polyolefin-based resin, melamine, tris (1,2-dihydroxy ethyl
L) isocyanurate, 1,3,5-tris (2-hydr
Roxyethyl) cyanurate and isocyanuric acid tria
Riruesuteru the like, are needed use one or two or more of these. The type of the phosphorus-containing compound represented by the general formula (1) used in the polyolefin resin composition according to the present invention is not particularly limited, but may be dimethacryloyl phosphate, di (methacryloyloxy). Methyl) phosphate, di (2-methacryloyloxyethyl) phosphate, di (3-methacryloyloxypropyl) phosphate, diacryloylphosphate, di (acryloyloxymethyl) phosphate, di (2-acryloyloxyethyl) phosphate Fate, di (3-acryloyloxypropyl) phosphate, trimethacryloyl phosphate, triacryloyl phosphate, trimethacryloyloxymethyl phosphate, trimethacryloyl (2-oxyethyl) phosphate Eto, tri methacryloyl (3-
(Oxypropyl) phosphate, triacryloylphosphate, triacryloyloxymethylphosphate, triacryloyl (2-oxyethyl) phosphate, triacryloyl (3-oxypropyl) phosphate, dimethacryloylphosphonic acid, di (methacryloyloxymethyl) ) Phosphonic acid, di (2-methacryloyloxyethyl) phosphonic acid, di (3-methacryloyloxypropyl) phosphonic acid, diacryloylphosphonic acid, di (acryloyloxymethyl)
Phosphonic acid, di (2-acryloyloxyethyl) phosphonic acid, di (3-acryloyloxypropyl) phosphonic acid, dimethacryloylphosphinic acid, di (methacryloyloxymethyl) phosphinic acid, di (2-
Methacryloyloxyethyl) phosphinic acid, di (3
-Methacryloyloxypropyl) phosphinic acid, diacryloylphosphinic acid, di (acryloyloxymethyl) phosphinic acid, di (2-acryloyloxyethyl) phosphinic acid, di (3-acryloyloxypropyl) phosphinic acid, and the like. One or more of these are suitably used. In the present invention, the above-mentioned phosphorus-containing compound and methacryloyl phosphate, methacryloyloxymethyl phosphate, (2-methacryloyloxyethyl) phosphate, (3-methacryloyloxypropyl) phosphate, acryloyl phosphate, Acryloyloxymethyl phosphate, (2
-Acryloyloxyethyl) phosphate, (3-
(Acryloyloxypropyl) phosphate, methacryloylphosphonic acid, methacryloyloxymethylphosphonic acid, (2-methacryloyloxyethyl) phosphonic acid, (3-methacryloyloxypropyl) phosphonic acid, acryloylphosphonic acid, acryloyloxymethylphosphonic acid , (2-acryloyloxyethyl) phosphonic acid, (3-acryloyloxypropyl) phosphonic acid, methacryloylphosphinic acid, methacryloyloxymethylphosphinic acid, (2-methacryloyloxyethyl) phosphinic acid, (3-methacryloyloxypropyl) Phosphinic acid, acryloylphosphinic acid, acryloyloxymethylphosphinic acid, (2-acryloyloxyethyl) phosphinic acid, (3-A Leroy oxy propyl) monofunctional monomers such as phosphine acid may be used in combination. In the polyolefin resin composition according to the present invention, the nitrogen-containing compound is contained in an amount of 0.5 to 30 parts by weight, more preferably 1 to 20 parts by weight, based on 100 parts by weight of the polyolefin resin. is necessary. If the content of the nitrogen-containing compound is less than 0.5 part by weight based on 100 parts by weight of the polyolefin resin, the flame retardancy of the polyolefin resin composition becomes insufficient. The mechanical properties and the like of the secondary processed product are reduced, and the practicality is poor. In the polyolefin resin composition according to the present invention, the phosphorus-containing compound represented by the general formula (1) is added in an amount of 1 to 100 parts by weight of the polyolefin resin.
It is necessary to contain 50 parts by weight, more preferably 2 to 40 parts by weight. If the content of the phosphorus-containing compound is less than 1 part by weight based on 100 parts by weight of the polyolefin resin, the crosslinkability and flame retardancy of the polyolefin resin composition become insufficient. In addition, the mechanical properties and the like of the secondary processed product are degraded, resulting in poor practicality. Further, in the polyolefin resin composition according to the present invention, the total amount of the nitrogen-containing compound and the phosphorus-containing compound is 5 parts by weight or more, more preferably 10 parts by weight, based on 100 parts by weight of the polyolefin resin. As described above, it is necessary that it be contained. If the total amount of the nitrogen-containing compound and the phosphorus-containing compound is less than 5 parts by weight based on 100 parts by weight of the polyolefin resin, the flame retardancy of the polyolefin resin composition becomes insufficient. [0021] In the polyolefin resin composition according to the present invention, the polyolefin resin is an essential component, the upper
Ki窒-containing compounds and the formula in addition to the phosphorus-containing compound represented by (1), red phosphorus, red phosphorus acids and ammonium polyphosphate, such as the surface of the particle surface is coated with a resin-treated red phosphorus, Karubamirupori ammonium phosphate, One or two or more of phosphorus-containing compounds such as condensed polyphosphates such as polyphosphoramide, hydrated metal hydroxides, and basic magnesium carbonate may be contained. The content of the flame retardant aid is not particularly limited, but is preferably not more than 100 parts by weight based on 100 parts by weight of the polyolefin resin. If the content of the flame retardant aid exceeds 100 parts by weight with respect to 100 parts by weight of the polyolefin resin, the mechanical strength and the like of the secondary processed product will be reduced and the practicality will be poor. In the polyolefin resin composition according to the present invention, divinylbenzene, diallylbenzene, trimethylolpropane trimethacrylate, ethylvinylbenzene, 1,9-nonanediol dimethacrylate, One or more polyfunctional monomers such as acid triallyl ester, isophthalic acid diallyl ester, isobutyl methacrylate, isodecyl methacrylate, tridecyl methacrylate, cyclohexyl methacrylate, 2-hydroxyethyl methacrylate, lauryl acrylate, stearyl acrylate, and 2-hydroxyethyl acrylate Two or more kinds may be contained in an appropriate amount. Further, in the polyolefin resin composition according to the present invention, a crosslinking initiator such as a peroxide, a phenolic resin,
An appropriate amount of one or more of various additives such as an amine-based or sulfur-based antioxidant, a metal harm inhibitor, a stabilizer, an ultraviolet absorber, an antistatic agent, a filler, and a colorant is contained. May be. The method for producing the polyolefin resin composition according to the present invention is not particularly limited. For example, a single screw extruder, a twin screw extruder, The mixture is melt-kneaded using a general-purpose kneading device such as a kneader, a Banbury mixer, a kneader, a roll, or the like, and molded into a sheet to form a molded sheet of the polyolefin-based resin composition. Next, the molded sheet of the polyolefin-based resin composition is irradiated with radiation such as an electron beam to be crosslinked, or a crosslinking initiator such as a peroxide is previously contained in the polyolefin-based resin composition, What is necessary is just to heat above the decomposition temperature of the crosslinking initiator to decompose the crosslinking initiator to effect crosslinking. The cross-linking by radiation such as an electron beam and the cross-linking by a cross-linking initiator may be performed independently or in combination. The degree of crosslinking of the obtained crosslinked product is not particularly limited, but is preferably 5 to 90% by weight, and more preferably 10 to 70% by weight. In the case of performing the above-mentioned cross-linking by radiation such as an electron beam, the irradiation dose of the radiation is not particularly limited, but is preferably 0.5 to 20 Mrad, and particularly preferably 1 to 8 Mrad. More preferred. If the irradiation dose of the radiation is less than 0.5 Mrad, a sufficient degree of crosslinking cannot be obtained. Conversely, if it exceeds 20 Mrad, the degree of crosslinking becomes too high and the processability and the quality of the processed product deteriorate. When crosslinking is carried out with the above crosslinking initiator, the type of crosslinking initiator is not particularly limited, but may be benzoyl peroxide, octanoyl peroxide, decanoyl peroxide, acetyl peroxide, tertiary butyl peroxide. Isobutyrate,
Peroxides such as cumene hydroperoxide;
One or more of these are preferably used. The content of the crosslinking initiator in the polyolefin resin composition according to the present invention is not particularly limited, but 0.05 to 5 parts by weight of the crosslinking initiator with respect to 100 parts by weight of the polyolefin resin. And more preferably 0.5 to 1 part by weight. When the content of the crosslinking initiator is less than 0.05 part by weight based on 100 parts by weight of the polyolefin resin,
If a sufficient degree of cross-linking cannot be obtained, and if it exceeds 5 parts by weight, the degree of cross-linking becomes too high, and the secondary workability and the quality of the secondary processed product deteriorate. [0032] [action] Polyolefin flame燃架bridge resin composition according to the invention, relative to the polyolefin resin, the phosphorus-containing compound is a specific amount contained, expressed in a specific nitrogen-containing compound and the general formula (1) As a result, it exhibits excellent flame retardancy and also has excellent secondary workability and quality of the secondary processed product. Further, since it does not contain a halogen-containing compound, there are almost no safety problems such as toxicity to human bodies and corrosiveness to equipment. EXAMPLES The present invention will be described in more detail with reference to the following examples. In the examples, “parts” means “parts by weight”. (Example 1) ( 1) Polyolefin resin composition, molding
Preparation of sheet and crosslinked sheet Polypropylene resin (melt index 0.5) 10
With respect to 0 parts, 2.5 parts of 1,3,5-tris (2-hydroxyethyl) cyanurate as the nitrogen-containing compound, 6 parts of di (2-methacryloyloxyethyl) phosphate as the phosphorus-containing compound and 6 parts 10 parts of ammonium polyphosphate (trade name “Sumisafe P”, manufactured by Sumitomo Chemical Co., Ltd.) is blended as a combustion aid and kneaded at 170 ° C. for 5 minutes at 60 rpm using a Labo Plastomill. Thus, a polyolefin resin composition was obtained. Next, the composition was press-molded at 170 ° C. to form a molded sheet having a thickness of 0.4 mm. The obtained molded sheet was irradiated with 4 Mrad of an electron beam at an accelerating voltage of 700 kV and crosslinked to prepare a crosslinked sheet. ( 2) Evaluation The degree of crosslinking, flammability and secondary workability of the crosslinked sheet obtained above were evaluated by the following methods, and the results are as shown in Table 1. Degree of crosslinking : The crosslinked sheet cut to a weight A (g) was immersed in xylene at 120 ° C. for 24 hours,
The mixture was filtered through a 00 mesh wire mesh, the dry weight B (g) of the residue remaining on the wire mesh was measured, and the degree of crosslinking (% by weight) was calculated by the following equation. Degree of crosslinking (% by weight) = [B (g) / A (g)] × 100 Flammability : In accordance with JIS D-1201 “Test method for flammability of organic materials for automobile interior”, A flammability test was performed, and the flammability was determined based on the following evaluation criteria. [Evaluation Criteria] Self-extinguishing Cross-linked sheet, once ignited in a windless atmosphere, extinguishes naturally after removing the ignition source. If the sheet continues to burn slowly after removing the ignition source Flammability: In a windless atmosphere, the crosslinked sheet once ignited continued to burn easily after removing the ignition source Case Secondary workability : A tensile test (elongation) of the crosslinked sheet was performed at 23 ° C. and 170 ° C. in accordance with JIS K-7113 “Plastic tensile test method”, and the secondary work was performed according to the following evaluation criteria. Sex was determined. [Evaluation criteria] ○ Elongation at 23 ° C. is 200% or more and elongation at 170 ° C. is 500% or more. ■ Elongation at 23 ° C. is 200% Less than or
Or elongation at 170 ° C. of less than 500% × ‥‥ elongation at 23 ° C. of less than 200% and elongation at 170 ° C. of less than 500% [ (Examples 2 to 6) Five kinds of polyolefin resin compositions and molded sheets were prepared in the same manner as in Example 1 with five kinds of compounding compositions shown in Table 1, and obtained. Five types of molded sheets were crosslinked under the conditions shown in Table 1 to prepare five types of crosslinked sheets. The results of evaluating the five types of crosslinked sheets obtained in the same manner as in Example 1 are as shown in Table 1. Comparative Example 1 To 100 parts of the same polypropylene resin as used in Example 1, 3.5 parts of melamine as a nitrogen-containing compound and 3.5 parts of melamine as a nitrogen-containing compound were added without blending a phosphorus-containing compound.
4 parts of divinylbenzene is blended as a polyfunctional monomer,
A polyolefin-based resin composition was prepared in the same manner as in Example 1. Next, a molded sheet and a crosslinked sheet were prepared in the same manner as in Example 1. The crosslinked sheet obtained above was evaluated in the same manner as in Example 1, and the results are as shown in Table 2. (Comparative Examples 2 to 7) Six kinds of polyolefin resin compositions and molded sheets were prepared in the same manner as in Example 1 with six kinds of compounding compositions as shown in Table 2, and obtained. The six types of molded sheets were crosslinked under the conditions shown in Table 2 to prepare six types of crosslinked sheets. The results of evaluating the six types of crosslinked sheets obtained in the same manner as in Example 1 are as shown in Table 2. [Table 1] [Table 2] As described above, the polyolefin-based flame-retardant crosslinkable resin composition according to the present invention has excellent flame retardancy, secondary workability and quality of secondary work products. Further, since it does not contain a halogen-containing compound, there is almost no safety problem.

Claims (1)

(57) [Claims 1] Melamine, tris (1,2-dihydroxyethyl) based on 100 parts by weight of a polyolefin resin.
Isocyanurate, 1,3,5-tris (2-hydroxy
(Siethyl) cyanurate and triallyl isocyanurate
Comprises at least one nitrogen-containing compound 0.5 to 30 parts by weight of phosphorus-containing compounds 1 to 50 parts by weight of the following general formula (1) selected from the group consisting of: it is contained, the nitrogen-containing compound A polyolefin-based flame-retardant crosslinkable resin composition, wherein the total amount of the compound and the phosphorus-containing compound is at least 5 parts by weight. Embedded image (In the formula, at _{least two of} R ₁ , R ₂ and R ₃ represent the following general formulas (a) or (b), and others represent a hydrogen atom, a hydroxyl group, or a linear or branched alkyl group having 20 or less carbon atoms. , Carbon number 2
Represents a linear or branched alkoxyl group, aryl group or aryloxyl group of 0 or less. [In the formulas (a) and (b), R ₄ and R ₆ represent a hydrogen atom or a methyl group, and R ₅ represents a linear or branched alkyl group having 30 or less carbon atoms.]