JPH06157866A - Flame-retardant resin composition - Google Patents

Abstract

PURPOSE:To obtain a resin composition excellent in flame retardancy, mechanical properties, moldability, impact resistance, tensile strength and elongation by mixing a resin composition comprising a number of specified polymers and a thermoplastic polyurethane with a phosphorus compound in a specified ratio. CONSTITUTION:This resin composition comprises 100 pts.wt. resin composition comprising 10-65wt.% graft copolymer prepared by grafting an aromatic vinyl compound (e.g. styrene) and a vinyl compound copolymerizable therewith (e.g. acrylonitrile) onto a rubbery polymer (e.g. polybutadiene rubber), 5-88wt.% vinyl copolymer comprising an aromatic vinyl compound (e.g. styrene) and a vinyl compound copolymerizable therewith (e.g. acrylonitrile), 1-40wt.% polymer comprising repeating units of the formula (wherein R1 is H or alkyl) and 1-35wt.% thermoplastic polyurethane (e.g. Desmopan 590, a product of Bayer AG) and 0.1-20 pts.wt. phosphorus compound (e.g. red phosphorus).

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flame-retardant resin composition containing a halogen-free compound and a non-halogen flame-retardant system.

[0002]

2. Description of the Related Art A rubber-reinforced type impact resistant resin represented by ABS resin is excellent in moldability, mechanical strength and dimensional stability, and is therefore a housing for OA equipment such as electric appliances, computers and word processors. It is widely used as a material, but for safety, these housing materials are often required to have high flame retardancy, and various regulations are defined.
In response to these demands, in the conventional rubber-reinforced impact resistant resin, a halogen-based flame retardant was added to the resin,
Its flame retardancy is enhanced. However, when a conventional halogen-based flame retardant is used, a large amount of a harmful compound having halogen as a component may be generated during combustion decomposition, which is a concern for the global environment.

In order to deal with such environmental problems, many attempts have been made to design a non-halogen flame-retardant resin that does not use a halogen-based flame retardant. At present, it is extremely difficult to find an alternative to flame retardants. US Pat. No. 463294
No. 6, in order to solve this problem, a styrene-acrylonitrile copolymer resin (AS resin),
A method of improving flame retardancy of a resin itself by blending a phenol aldehyde resin, a nitrogen-containing organic compound and a phosphorus-based organic compound with a thermoplastic resin represented by ABS resin is also disclosed in JP-A-4-45143. Discloses a method using a thermosetting resin and a phosphate compound.

[0004]

However, according to these methods, although the flame retardancy is excellent, there is peeling of the molded piece and deterioration of impact resistance, and the practical performance as a resin in terms of appearance and strength. There was a problem that was inferior. An object of the present invention is to solve the problem in the ABS resin composition.

[0005]

Therefore, as a result of intensive studies for solving the above problems, the present inventors have found that a flame-retardant resin blended with an ABS resin, a thermoplastic polyurethane, a phenol novolac resin and a phosphorus compound is excellent. The present invention has been completed by finding that it exhibits flame retardancy, impact strength, working fluidity and tensile elongation.

That is, the present invention provides the following (A), (B),
It is a flame-retardant resin composition containing 0.1 to 20 parts by weight of the phosphorus compound (E) with respect to 100 parts by weight of the resin composition of (C) and (D). (A) Aromatic vinyl compound and graft copolymer obtained by grafting a vinyl compound copolymerizable therewith to a rubbery polymer 10 to 65% by weight (B) Aromatic vinyl compound and vinyl compound copolymerizable therewith 5 to 89% by weight of a vinyl copolymer (C) 2 to 35% by weight of a thermoplastic polyurethane (D) 1 to 40% by weight of a polymer containing a compound unit represented by the following general formula (1) as a constituent component

[0007]

[Chemical 2] (R ₁ is a group selected from hydrogen or _one of alkyl groups.)

The resin composition of the present invention is excellent in flame retardancy and practical performance of resin, particularly impact resistance, tensile elongation and molding processability. The present invention will be described in detail below. Examples of the aromatic vinyl compound used in the present invention include styrene and α
-Methyl styrene, paramethyl styrene, etc. are mentioned. Particularly preferred is styrene.

Specific examples of the vinyl compound copolymerizable therewith include methyl methacrylate, methyl acrylate,
Alkyl (meth) acrylates such as ethyl acrylate, (meth) acrylic acids such as acrylic acid and methacrylic acid, vinyl cyanide monomers such as acrylonitrile and methacrylonitrile, and α, β-unsaturated carboxylic acids such as maleic anhydride. , N-phenylmaleimide, N-methylmaleimide, N-cyclohexylmaleimide and other maleimide-based monomers, and glycidyl group-containing monomers such as glycidylmethacrylate are used. Among these compounds, alkyl (meth) acrylates, vinyl cyanide monomers and maleimide monomers are preferable, and acrylonitrile and N-phenylmaleimide are more preferable. These vinyl compounds may be used alone or in combination of two or more.

Any rubbery polymer having a glass transition temperature of 0 ° C. or lower can be used. Specifically, polybutadiene, styrene-butadiene copolymer rubber,
Diene rubber such as acrylonitrile-butadiene copolymer rubber, acrylic rubber such as polybutyl acrylate, polyisoprene, polychloroprene, ethylene-propylene rubber, ethylene-propylene-diene terpolymer rubber,
Styrene-butadiene block copolymer rubber, styrene-
Block copolymers such as isoprene block copolymer rubbers and hydrogenated products thereof can be used. Among these polymers, polybutadiene, styrene-butadiene copolymer rubber, acrylonitrile-butadiene copolymer rubber and the like are preferable.

The proportion of the rubber-like polymer in the graft copolymer (A) is used in the range of 30 to 95% by weight, but it is preferably 50 from the viewpoint of the balance between impact resistance and process fluidity.
To 90% by weight. The ratio of the rubbery polymer to the graft component in the graft copolymer (A) is specifically measured by dissolving the polymer produced by the polymerization in acetone and separating and removing the insoluble matter with a centrifuge. You can The component that dissolves in acetone is the component that did not undergo graft reaction in the copolymerized polymer (non-graft polymer), and the value obtained by subtracting the amount of rubber polymer from the acetone insoluble content is defined as the value of the graft component. To be done.

The thermoplastic polyurethane as the component (C) of the present invention comprises a diisocyanate compound, one or more compounds selected from compounds containing two or more hydroxyl groups, and a compound having a functional group capable of reacting with an isocyanate group. You can get it.

For example, as the diisocyanate compound, aromatic, aliphatic and alicyclic diisocyanate compounds are used. For example, 2,4-tolylene diisocyanate,
2,6-Tolylene diisocyanate, phenylene diisocyanate, 4,4'-diphenylmethane diisocyanate, 4,4'-diphenyl diisocyanate, 1,5
-Naphthylene diisocyanate, 3,3'-dimethylbiphenyl-4,4'-diisocyanate, o-, m- or p-xylene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, dodecane methylene diisocyanate, cyclohexane diisocyanate Diisocyanates such as dicyclohexylmethane diisocyanate are used.

The compound containing two or more hydroxyl groups is
Molecular weight 300 to 10,000, preferably 500 to 5,
000, and contains a molar equivalent that reacts with diisocyanate. These are glycols having 2 to 8 carbon atoms. For example, ethylene, trimethylene, tetramethylene, hexene, propylene glycol, etc. and adipic acid, succinic acid, glutaric acid, suberic acid, sebacic acid, etc., which are saturated aliphatic dicarboxylic acids having 4 to 10 carbon atoms, or aromatic dicarboxylic acids Condensates obtained from certain phthalic acid, isophthalic acid, terephthalic acid, etc., polyester glycols obtained by copolymerization of alkylene glycol and lactone group, such as polylactone diol, polycaprolactone diol, polyenant lactone diol, etc. Condensate of 2-4 alkylene oxide, condensate of alkylene oxide having 2-4 carbon atoms and alkylene glycol, polyalkylene glycol having 2-4 carbon atoms, polyalkylene obtained by ring-opening polymerization of tetrahydrofuran, etc. Ether glycols, further dihydroxy polyalkylene ethers, hydroxy polycarbonates and the like may be used as well.

Among these, polytetramethylene ether glycol, dihydroxy polyethylene adipate,
Polyethylene glycol, polypropylene glycol, etc. are suitable.

In addition to the diols, a compound having a functional group capable of reacting with an isocyanate group can be used as a molecular chain length regulator. For example, carbon number 2
6, which are saturated aliphatic glycols, ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, butane 1,2-diol, butane 1,3
-Diol, butane 1,4-diol, butane 2,3-
Examples thereof include diol and butane 2,4-diol, hexanediol, and the like, and aromatic glycols such as 1,4-xylylene glycol and phenylene bis- (β-hydroxyethyl ether).

In addition, for example, a small amount of trifunctional or higher functional alcohols, trimethylolpropane, glycerin,
Hexanetriol and the like may be used at the same time. The thermoplastic polyurethane is produced by a known method using the above compound.

The polymer (D) used in the present invention is a polymer containing the compound unit represented by the general formula (1) as a constituent, and is generally synthesized by a condensation reaction of phenol and aldehyde. The so-called phenol novolac resin. Specifically, for example, phenol formaldehyde novolac resin, tertiary-butylphenol formaldehyde novolac resin, paraoctylphenol formaldehyde novolac resin, paracyanophenol formaldehyde novolac resin and the like, and copolymers and mixtures thereof are typically mentioned. A preferable average weight molecular weight is in the range of 300 to 10,000. Within this range, the polymer (D) has a high compatibility with the polymer (B) and has good mechanical properties after blending.

Polymer (A) in the resin composition,
The proportions of (B), (C), and (D) differ depending on the required level of flame retardancy and the required level of mechanical strength, but (A), (B), (C), ( D) total 10
When it is 0% by weight, the component (A) is 10 to 65% by weight,
It is necessary that the component (B) is 5 to 88% by weight, the component (C) is 1 to 35% by weight, and the component (D) is 1 to 40% by weight.

When the proportion of (A) is less than 10% by weight, the impact resistance is low, and when it exceeds 65% by weight, the working fluidity is lowered. More preferably, it is 20 to 55% by weight. If the proportion of (B) is less than 5% by weight, the process fluidity is extremely low. If it exceeds 88% by weight, the impact resistance is low. More preferably, it is 20 to 79% by weight. (C)
When the ratio is less than 1% by weight, impact resistance and process fluidity are low. When it exceeds 35% by weight, the heat resistance is low. More preferably, it is 5 to 20% by weight. The ratio of (D) is 1
If it is less than wt%, the flame retardant effect is not sufficient. On the other hand, if it exceeds 40% by weight, the mechanical strength of the resin will be lowered, so that it cannot be used. It is more preferably 2 to 30% by weight.

The copolymer (B) may contain a non-graft component produced during the production of the graft copolymer (A). However, the composition and content of the non-graft copolymer component derived from this graft copolymer (A) are
Even when this is contained in the copolymer (B),
100% by weight of the total of (A), (B), (C) and (D)
In this case, the component (B) needs to be in the range of 5 to 88% by weight.

(E) in the composition of the present invention refers to an ordinary phosphorus-based flame retardant, such as red phosphorus, phosphine, hypophosphorous acid, phosphorous acid, metaphosphoric acid, pyrophosphoric acid,
Inorganic phosphorus compounds such as phosphoric anhydride, general formula,

[0023]

[Chemical 3] (In the formula, R ₁ , R ₂ and R ₃ represent a hydrocarbon residue, preferably an alkyl group having 1 to 8 carbon atoms and a carbon number of 6 to 12
The aromatic residue of R ₁ , R ₂ and R ₃ may be the same or different. ) Is used.

Specifically, trimethyl phosphate, triethyl phosphate, tripropyl phosphate, tributyl phosphate, tripentyl phosphate, trihexyl phosphate, tricyclohexyl phosphate, triphenyl phosphate, tricresyl phosphate, trixylenyl phosphate, dimethylethyl phosphate. , Methyldibutylphosphate, ethyldipropylphosphate and the like. These phosphoric acid esters can be used alone or in combination of two or more kinds. Also, a condensation type phosphoric acid ester can be used. That is, the following general formula

[0025]

[Chemical 4] (In the formula, R ₁ , R ₂ and R ₃ represent the same or different hydrocarbon residues, R ₄ , R ₅ , R ₆ and R ₇ represent a hydrogen atom or a hydrocarbon residue, R ₄ , R ₅ , R ₆ and R ₇ may be the same or different, and n represents the degree of polymerization.)
Compounds represented by the following are preferable, and those in which R ₁ , R ₂ and R ₃ are all phenyl groups and R ₄ , R ₅ , R ₆ and R ₇ are all hydrogen atoms are preferable, It is not limited to these. These compounds may be used alone or
A combination of two or more species can be used.

A particularly preferred phosphorus flame retardant is red phosphorus. Red phosphorus has a high flame retarding effect, and the required flame retardancy can be obtained with a small amount of addition, so it is advantageous in that mechanical properties, especially tensile strength and rigidity, are retained compared to other phosphorus compounds. is there. The content of the phosphorus compound is determined according to the required level of flame retardancy, but it is necessary that the total amount of the resin composition is 0.1 to 20 parts by weight with respect to 100% by weight. If it is less than 0.1 part by weight, the required flame retardant effect cannot be exhibited. If it exceeds 20 parts by weight, the mechanical strength of the resin is lowered. It is preferably in the range of 0.5 to 15 parts by weight, and particularly preferably in the case of phosphorus compounds, 10 to 10 parts by weight.
The range is 15 parts by weight, and in the case of red phosphorus, 0.5 to 1
It is in the range of 0 parts by weight.

For the purpose of modifying the resin, the resin composition of the present invention contains, if necessary, conventional additives such as lubricants, antistatic agents, antioxidants, ultraviolet absorbers, colorants,
Surface modifiers, dispersants, plasticizers and the like can be added. Regarding the method for producing the resin composition in the present invention,
There is no particular limitation, and it can be produced by an ordinary method, for example, melt blending by extrusion kneading.

[0028]

The present invention will be described in detail with reference to the following examples. (Hereinafter, "part" means "part by weight").

(Production of Graft Copolymer 1) To 45 parts of polybutadiene rubber latex (average particle diameter of 3,000 angstroms), 100 parts of deionized water and 1.5 parts of potassium rosinate were added, and the gas phase part was replaced with nitrogen. After doing, 70 ℃
The temperature was raised to. Subsequently, 15 parts of acrylonitrile, 40 parts of styrene, 0.6 parts of tertiary dodecyl mercaptan.
Part, cumene hydroperoxide (0.1 part by weight), 50 parts of deionized water, 0.2 part of sodium formaldehyde sulfoxylate, 0.004 parts of ferrous sulfate.
Parts, ethylenediaminetetraacetic acid disodium salt 0.0
An aqueous solution prepared by dissolving 4 parts was added over 7 hours,
The reaction was completed at a polymerization temperature of 0 ° C. The content of acrylonitrile units in the components excluding the rubbery polymer determined by an infrared spectrophotometer was 27% by weight. The graft copolymer latex was salted out and dehydrated, and then dried to obtain a powdery graft copolymer A.

Acetone insoluble matter in the graft copolymer, that is, the component corresponding to the graft copolymer component A according to claim 1 is 68% by weight, and acetone soluble matter, that is, the vinyl copolymer component according to claim 2. The component corresponding to B was 32% by weight. The composition of the acetone insoluble matter in the graft copolymer was measured by an infrared spectrophotometer to find that the content of the rubbery polymer was 66% by weight and the content of the graft component was 3%.
It was 4% by weight. Similarly, when the composition of the acetone-soluble component was measured, the proportion of acrylonitrile units was 27% by weight and the proportion of styrene units was 73% by weight.

(Copolymer 2) The solution viscosity (viscosity at 25 ° C. using a methyl ethyl ketone solvent at a polymer concentration of 10% by weight) is 9 centipoise, the acrylonitrile unit in the resin is 27% by weight, and the styrene unit is 73% by weight. An AS resin having a composition (acrylonitrile-styrene copolymer).

(Polymer C) As the thermoplastic polyurethane resin, Desmopan 590 (polyester polyurethane hardness Shore D 42) manufactured by Bayer was used.

(Polymer D) Phenol formaldehyde novolac resin (Mitsui Toatsu Chemical Co., Ltd. # 1000ws
A standard softening point of 99 to 105 ° C.) was used.

(Phosphorus compound E) E-1: Red phosphorus E-2: Triphenyl phosphate.

Examples 1 to 4 and Comparative Examples 1 to 5 The resins and phosphorus-based flame retardants prepared as described above were blended in the composition shown in Table 1 and the mixture was heated in a twin-screw extruder with the cylinder temperature set at 220 ° C. Kneading and granulation were performed to obtain pellets. Then, a test piece for measuring physical properties was obtained by injection molding at a molding temperature of 220 ° C. The physical properties of the resin were evaluated using this test piece and granulated pellets. The results are shown in Table 2. Melt flow rate: Based on JIS K-7210. Izod impact value: Based on ASTM D256 (notched thickness 1/4 inch). Tensile Strength and Elongation: Measured according to ASTM D638. The other evaluation methods are as follows. Flammability measuring method: A test piece cut out after compression molding (width 2.5 mm x thickness 1 mm) is placed horizontally. The flame of the gas burner is brought close to the end of the test piece in a windless state, and the flame is applied for 5 seconds to ignite. Self-extinguishing property refers to the case of spontaneous extinction within 10 seconds after moving away the flame of the gas burner, and flammability refers to the case where combustion does not stop until the test piece burns out even if the flame of the gas burner is moved away. .

Presence or absence of drops: The test piece melts during the measurement of flammability. In some cases, it was melted and dropped, and in other cases, it was not dropped. It should be noted that the less the dropping, the smaller the spread of fire, which is preferable in practice.

[0037]

[Table 1]

[0038]

[Table 2]

[0039]

INDUSTRIAL APPLICABILITY The resin composition of the present invention exhibits excellent flame retardancy without using an environmentally harmful halogen-based flame retardant, and has good mechanical properties, particularly good moldability, impact resistance, and Shows tensile elongation.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Internal reference number FI Technical display location C08L 25/02 LDW 9166-4J LDY 9166-4J LEE 9166-4J 55/02 LMB 7142-4J LMC 7142 -4J LME 7142-4J LMF 7142-4J // C08L 75/04 NGG 8620-4J (C08L 51/04 25:02 75:04 61:06)

Claims (3)

[Claims] 1. The following (A), (B), (C) and (D)
A flame-retardant resin composition containing 0.1 to 20 parts by weight of the phosphorus compound (E) based on 100 parts by weight of the resin composition. (A) Aromatic vinyl compound and graft copolymer obtained by grafting a vinyl compound copolymerizable therewith to a rubbery polymer 10 to 65% by weight (B) Aromatic vinyl compound and vinyl compound copolymerizable therewith 5 to 88% by weight of a vinyl copolymer (C) 1 to 35% by weight of a thermoplastic polyurethane (D) 1 to 40% by weight of a polymer containing a compound unit represented by the following general formula (1) as a constituent component [Chemical 1] (R ₁ is hydrogen or a group selected from one of alkyl groups) 2. The flame-retardant resin composition according to claim 1, wherein the phosphorus compound is red phosphorus. 3. The flame-retardant resin composition according to claim 1, wherein the copolymerizable vinyl compound is a vinyl cyanide compound.