JPH0662783B2 - Flame retardant masterbatch - Google Patents

Description

TECHNICAL FIELD The present invention relates to a flame-retardant masterbatch, and more specifically to the dispersibility of a flame retardant, flame retardancy, thermal stability, mechanical strength and moldability. The present invention relates to a flame-retardant masterbatch having excellent performance and suitable for styrene resins, polyphenylene ether, etc.

[Conventional technology]

Conventionally, addition-type flame-retardant resin, which is a molding material, generally has a flame-retardant agent directly added to the resin and most of the flame-retardant agent is liquid or powder. Kneading the fuel.

On the other hand, as another addition method, a resin composition having a high content of a flame retardant (flame retardant masterbatch) is prepared in advance,
There is a masterbatch method in which this flame-retardant masterbatch is added to a resin to obtain a flame-retardant resin.

This masterbatch method has attracted attention because it can easily obtain an arbitrary flame-retardant resin by a simple mixing method of a resin and a flame-retardant masterbatch in a molding step, as compared with a general method.

However, in the conventional flame-retardant masterbatch, the resin component that is the base polymer, generally, a resin of the same series as the partner resin to which the masterbatch is added is used,
The resin has a high melting temperature and a high melt viscosity. Therefore,
The flame-retardant resin obtained by using the conventional flame-retardant masterbatch does not have sufficient dispersibility of the flame retardant, and as a result, it causes deterioration of flame retardancy, poor molding appearance and mechanical strength.

Further, the effect of imparting moldability and mechanical strength is not sufficient.

[Problems to be Solved by the Invention]

The present invention has been made on the basis of the above-mentioned conventional technology, and is excellent in thermal stability and, when added to a resin, is excellent in dispersibility, and as a result, excellent flame retardancy and molding appearance are obtained, and further mechanical properties are obtained. It is an object of the present invention to provide a flame-retardant masterbatch capable of giving a composition excellent in dynamic strength and molding processability.

[Means for Solving the Problems]

The present invention provides a flame retardant masterbatch containing 5 to 50% by weight of the following block copolymer and 95 to 50% by weight of a flame retardant.

The block copolymer is (AB) n, (AB) nA, or (AB) nX [In the formula, A is a block mainly composed of an aromatic vinyl compound (hereinafter referred to as "block A". , B is a block containing a conjugated diene as a main component (hereinafter sometimes referred to as “block B”), n is an integer of 1 to 8, and X is a coupling agent residue] and is aromatic. Content of vinyl compound is 10-7
Aromatic vinyl compound-conjugated diene block copolymer and / or hydrogenated product thereof, which has 0% by weight, a conjugated diene content of 90 to 30% by weight, and a weight average molecular weight of 20,000 to 500,000.

Examples of the structure of the block copolymer used in the flame retardant masterbatch of the present invention include (AB) n, (AB) nA, and (AB) nX, but are not limited thereto. Not a thing.

Here, examples of the vinyl aromatic compound used in the block copolymer of the present invention include styrene, t-butylstyrene, α-methylstyrene, p-methylstyrene, divinylbenzene, 1,1-diphenylstyrene, N, N. -Diethyl-p-aminoethylstyrene, N, N-diethyl-p-aminoethylstyrene, vinyl pyridine and the like can be mentioned, and styrene and α-methylstyrene are particularly preferable.

Block A includes one of these vinyl aromatic compounds.
Examples thereof include polymers of only one kind or block or random copolymers of two or more kinds in combination.

Further, as the conjugated diene used in the block copolymer of the present invention, 1,3-butadiene, isoprene, 2,3
-Dimethyl-1,3-butadiene, 1,3-pentadiene, 2-methyl-1,3-pentadiene, 1,3-hexadiene, 4,5-diethyl-1,3-octadiene,
Examples thereof include 3-butyl-1,3-octadiene and chloroprene, but preferably 1,3-butadiene, isoprene and 1,3-pentadiene, and more preferably 1,
It is 3-butadiene.

As the block B, a homopolymer of these conjugated dienes,
Alternatively, a block or random copolymer in which two or more kinds are combined can be mentioned.

X in the general formula is a coupling agent residue, and examples of the coupling agent include diethyl adipate,
Divinylbenzene, tetrachlorosilicon, butyltrichlorosilicon, tetrachlorotin, butyltrichlorotin, dimethylchlorosilicon, tetrachlorogermanium, 1,2-dibromoethane, 1,4-chloromethylbenzene, bis (trichlorosilyl) ethane, epoxidation Linseed oil, tolylene diisocyanate, 1,2,4-benzene triisocyanate and the like can be mentioned.

The content of the aromatic vinyl compound in the block copolymer is
10 to 70% by weight (that is, the content of conjugated diene is 9
0 to 30% by weight), preferably 10 to 60% by weight (conjugated diene content = 90 to 40% by weight), and more preferably 10 to 50% by weight (conjugated diene content = 90 to 50% by weight). Aromatic vinyl compound content of 10% by weight
In the case of less than, the flame-retardant masterbatch cannot be produced in a stable state, and when the flame-retardant masterbatch is added to the resin, the dispersibility of the masterbatch is deteriorated, and as a result, flame retardancy and molding appearance are obtained. This may cause deterioration in the effect of imparting properties and mechanical strength.

On the other hand, if the aromatic vinyl compound content exceeds 70% by weight, sufficient mechanical strength imparting effect cannot be obtained.

The weight average molecular weight of the block copolymer used in the present invention is 20,000 to 500,000, preferably 70,000 to 450,000. When it is less than 20,000, the dispersibility of the flame retardant in the flame retardant masterbatch is deteriorated, and as a result, the flame retardancy and the molding appearance are deteriorated, and the effect of imparting mechanical strength is poor. On the other hand, when it exceeds 500,000, it is difficult to obtain a masterbatch having a high concentration of the flame retardant, and the dispersibility of the flame retardant masterbatch is deteriorated. As a result, the effect of imparting flame retardancy and mechanical strength is poor, and further, The effect of imparting molding processability is also inferior.

The block copolymer of the present invention may be a hydrogenated product thereof in addition to the aromatic vinyl compound-conjugated diene block copolymer as described above.

This hydrogenated product is at least 80%, preferably 90% or more of the double bond of the conjugated diene portion of the block B in the aromatic vinyl compound-conjugated diene block copolymer,
More preferably, 95 to 100% is hydrogenated and saturated, which improves the thermal stability during processing and the chemical resistance of the product.

The block copolymer of the present invention includes block A and block B.
Living anion polymerization of (including taper block) using an organic alkali metal compound as an initiator in an organic solvent to obtain a block copolymer, and then, if necessary, further hydrogenation of the block copolymer can get.

Preferred block copolymers used in the present invention are described below, and more preferred block copolymers are described below.
, Respectively. Use of these preferable block copolymers makes it possible to obtain a flame-retardant masterbatch having further excellent effects aimed at by the present invention.

Among the block copolymers of the present invention, an aromatic vinyl compound-conjugated diene block copolymer represented by (AB) n or (AB) nX.

In the block copolymer of the present invention, block B is a random copolymer block of a conjugated diene and an aromatic vinyl compound, or a tapered block type aromatic vinyl compound-conjugated diene block copolymer in which the aromatic vinyl compound is gradually increased. Polymer.

Further, preferably, the block copolymer is (AB) nX [wherein A is a block containing an aromatic vinyl compound as a main component, and B is an aromatic vinyl compound containing 2 to 10% by weight of an aromatic vinyl compound]. Random copolymer block with conjugated diene, X is a coupling agent residue, and n is an integer of 2 to 8].

The block copolymer is ABA, or (AB)
nX [In the formula, A is a block mainly composed of an aromatic vinyl compound, and the total amount of A is 50 to 50% of the total amount of the aromatic vinyl compound.
97% by weight of a block, B is a copolymer of a conjugated diene and an aromatic vinyl compound, the block B is composed of 2 to 10 tapered blocks in which the aromatic vinyl compound is gradually increased, and n is 3 An aromatic vinyl compound-conjugated diene block copolymer represented by the formula:

Next, as the flame retardant used in the present invention, general rubber,
Flame retardants used in polymers such as resins can be used.

Examples of the flame retardant include halogen-containing compounds, phosphorus-containing compounds, nitrogen-containing compounds, silicon-containing compounds and the like.

Among the flame retardants, examples of the halogen-containing compound include tetrabromobisphenol A or tetrabromobisphenol A-bis (2-hydroxyethyl ether) and tetrabromobisphenol A-bis (2,3-
Tetrabromobisphenol A derivative such as dibromopropyl ether), hexabromodiphenyl ether,
Octabromodiphenyl ether, decabromodiphenyl ether, bis (tribromophenoxy) ethane, hexabromocyclodecane and the like can be mentioned.

As the halogen-containing compound, for example, monobromophenol, tribromophenol, pentabromophenol, tribromocresol, dibromopropylphenol, tetrabromobisphenol S, cyanuric chloride or the like is polymerized, or these and the above halogen compounds are selected. An oligomeric halogen compound obtained by copolymerization with one or more selected halogen compounds can be used. Further, as the halogen-containing compound, a polycarbonate oligomer of tetrabromobisphenol A,
Examples thereof include a polycarbonate oligomer of tetrabromobisphenol A and bisphenol A, a polycarbonate oligomer of tetrabromobisphenol S, a polycarbonate oligomer of tetrabromobisphenol S and bisphenol S, and the like.

Furthermore, examples of the halogen-containing compound include halogenated epoxy oligomers represented by the following general formula (I).

[In the formula, R ¹ and R ² are the same or different, (Here, Y is a bromine atom or chlorine atom, j is 0 to 5
Is a bromine atom or a chlorine atom, i is an integer of 1 to 4, and m is 0 to 10. Further, among the flame retardants, examples of the phosphorus-containing compound include organic phosphate compounds represented by the following general formula (II).

(In the formula, R ^{3 to} R ⁵ are the same or different and each represents an aliphatic, alicyclic or aromatic hydrocarbon residue, and the hydrocarbon residue is substituted with a halogen atom or another substituent. Specific examples of this organic phosphate compound include triphenyl phosphate, tricresyl phosphate, trixylenyl phosphate, triisopropyl phosphate, tripentyl phosphate, trihexyl phosphate, tricyclohexyl phosphate, tris-phosphate.
In addition to (dibromopropyl) -phosphate, tris- (chlorophenyl) -phosphate, 4-chlorophenyldiphenylphosphate and the like, bisphenol A phosphate polymer, cresyldiphenylphosphate dimer and the like can be mentioned.

Examples of the phosphorus-containing compound include organic phosphate compounds represented by the following general formula (III).

(In the formula, R ⁶ represents an aliphatic or aromatic hydrocarbon residue, the aromatic hydrocarbon residue may be substituted with an alkyl group, and R ^{7 to} R ⁸ are the same or different. May be an aliphatic or aromatic hydrocarbon residue, and the aromatic hydrocarbon residue may be substituted with an alkyl group.) Of the organic phosphate compound represented by the general formula (III) Specific examples include phenylphosphonic acid, dimethyl ester, diethyl ester, dibutyl ester,
Di-n-amyl ester, diphenyl ester or di-p-butylphenyl ester; 4-methylphenylphosphonic acid diethyl ester, diphenyl ester or di-p-tolyl ester; methylphosphonic acid dimethyl ester, diethyl ester , Dipropyl ester, diisopropyl ester, diphenyl ester, di-m-tolyl ester, or di-p-tolyl ester; diethyl ester or dibutyl ester of ethylphosphonic acid; diethyl ester or dipropyl ester of propylphosphonic acid ;
Butylphosphonic acid dimethyl ester or dibutyl ester; Isobutylphosphonic acid diethyl ester or dibutyl ester, isoamylphosphonic acid diethyl ester or diphenyl ester; n-hexylphosphonic acid diethyl ester or dibutyl ester; n-heptylphosphonic acid diethyl ester or dibutyl ester; n-octylphosphonic acid diethyl ester or dibutyl ester; n-nonylphosphonic acid diethyl ester or dibutyl ester; n
-Diethylphosphonic acid diethyl ester or dibutyl ester; n-dodecylphosphonic acid diethyl ester or dibutyl ester; n-tetradecylphosphonic acid diethyl ester or dibutyl ester; n-octadecylphosphonic acid dibutyl ester Examples thereof include esters.

If necessary, a flame retardant auxiliary agent can be used in combination with the above flame retardants. Examples of the flame retardant aid include iron oxide, borax, barium metaborate, zirconium oxide, and antimony compounds such as antimony trioxide, antimony tetraoxide, antimony pentoxide, sodium antimonate, and antimony phosphate. Can be used alone or in combination of two or more. Of these flame retardant aids, antimony trioxide and sodium antimonate are preferred.

When these flame retardant aids are used together, more excellent flame retardancy can be obtained. The amount of the flame retardant aid used is usually about 10 to 40% by weight based on the flame retardant.

The flame-retardant masterbatch of the present invention is a composition containing the block copolymer and a flame retardant as main components, and the composition ratio of the block copolymer is 5 to 50% by weight, preferably 1
0-40% by weight, more preferably 15-35%, flame retardant 95-50% by weight, preferably 90-60%.
%, More preferably 85 to 65% by weight.

Less than 5% by weight of block copolymer (95% by weight of flame retardant
If it is more than 1), the masterbatch cannot be stably produced, and the effect of imparting mechanical strength is not sufficient. On the other hand, when the block copolymer exceeds 50% by weight (when the flame retardant is less than 50% by weight), in order to obtain a flame retardant resin having a predetermined flame retardant content, it is necessary to add a large amount of flame retardant masterbatch. It becomes necessary, and the economic effect peculiar to the masterbatch decreases, which is not preferable.

Various additives may be added to the flame-retardant masterbatch of the present invention, if necessary.

Examples of the additives include lubricants such as paraffin wax, stearic acid, n-butyl stearate, ketone wax, octyl alcohol, polysiloxane, ethylenebis stearamide; antioxidants such as 2,6-di-t-butyl. -4-methylphenol, 2- (1-methylcyclohexyl) -4,6-dimethylphenol,
2,2-methylene-bis- (4-ethyl-t-butylphenol), tris (dinonylphenyl) phosphite; UV absorbers such as p-t-butylphenyl salicylate, 2,2'-dihydroxy-4-methoxy. Benzophenone, 2- (2'-hydroxy-4'-m-octoxyphenyl) benzotriazole; Antistatic agents such as stearoamidopropyldimethyl-β-hydroxyethyl, ammonium urate; Stabilizers such as phosphites, epoxies Compounds, organic tin compounds and the like; coloring agents such as titanium oxide, carbon black and pigments. Further, a known plasticizer or the like can be added.

In particular, it is preferable to add the lubricant to the flame-retardant masterbatch of the present invention because the kneading temperature at the time of melt mixing the block copolymer and the flame-retardant can be lowered. The preferred blending ratio of the flame-retardant masterbatch and the lubricant is about 90 to 99.5% by weight of the flame-retardant masterbatch and about 10 to 0.5% by weight of the lubricant.

The flame-retardant masterbatch of the present invention is obtained by melt-kneading by adding the block copolymer, the flame-retardant and, if necessary, the additive.

The melt-kneading is performed using a processing machine such as a single-screw extruder, a multi-screw extruder, a Banbury mixer, or a kneader. Particularly preferably, by using a processing machine selected from a multi-screw extruder, a Banbury mixer, and a kneader, a more excellent flame retardant masterbatch of the present invention can be obtained.

As the resin to which the flame-retardant masterbatch of the present invention is added, styrene-based resins, polyphenylene ethers,
Aromatic vinyl compound-conjugated diene block copolymer,
Examples thereof include hydrogenated products of the block copolymer. Particularly preferred resins are styrene resins and polyphenylene ethers. Here, the styrene-based resin, an aromatic vinyl compound as an essential component, a homopolymer, a copolymer, a graft copolymer such as polystyrene, high impact polystyrene, styrene-methyl methacrylate copolymer, styrene-acrylonitrile Examples thereof include copolymers, ABS resins, MBS resins, AES resins, and the like, with polystyrene and high-impact polystyrene being preferred.

The polyphenylene ethers include polyphenylene ether and modified polyphenylene ether.

〔Example〕

Hereinafter, the present invention will be specifically described with reference to examples, but the present invention is not limited to these examples. The parts and% in the examples are based on weight.

In addition, each measurement item in the examples was evaluated as follows.

Evaluation of production stability of flame-retardant masterbatch The production state and shape of pellets in flame-retardant masterbatch production were visually evaluated.

That is, the production status of the pellets was evaluated as ◯ when the pellets can be stably produced, Δ when the pellets are slightly unstable, and x when the pellets cannot be produced because they are unstable. Also,
The shape of the pellets was evaluated as ◯ when the shapes were uniform, Δ when the shapes were somewhat irregular, and as × when the shapes were irregular.

Izod impact strength Measured according to JIS K7110. That is, using an N70BII type injection molding machine manufactured by Japan Steel Works, Ltd., temperature 2
At 20 ° C., an Izod impact test piece having a thickness of ¼ inch defined in JIS K7110 was prepared and evaluated.

Molding appearance Using a SAV type injection molding machine manufactured by Yamashiro Seiki Co., Ltd., vertical 9c
A flat plate having m, width 6 cm, and thickness 3 mm was prepared and evaluated.

◯: It has a smooth surface, and defects such as uneven gloss and flow marks are not recognized.

×: Defects such as uneven gloss and flow marks are observed.

Flame retardant under. Light. Based on Subject 94 defined by Laboratory (UL), the flame retardance of a test piece having a thickness of 1/8 inch was evaluated.

V-0 means self-extinguishing and BN means burning.

Reference Example The block copolymer, flame retardant and resin used in the examples are
It is as follows.

Block copolymers _{TR-1; A 1 -B 1} -A 2 -B 2 type block copolymer.

Here, A ₁ is a styrene polymer block having a bound styrene content of 15%, B ₁ is a butadiene polymer block having a bound butadiene content of 10%, A ₂ is a styrene polymer block having a bound styrene content of 25%, and B ₂ Has a bound butadiene content of 5
It is a 0% butadiene polymer block, and the weight average molecular weight of the copolymer is 150,000.

TR-2; A ₁ -B-A ₁ type block copolymer.

Here, A ₁ is a styrene polymer block having a bound styrene content of 7.5%, B is a butadiene polymer block having a bound butadiene content of 85%, and the weight average molecular weight of the copolymer is 160,000.

TR-3; A block copolymer produced by the following method, which is a block copolymer of A ₁ -B-A ₁ type, in which block B is a tapered block in which an aromatic vinyl compound gradually increases.

That is, 4,500 g of siloxane was charged into a washed and dried autoclave with a stirrer and a jacket, and then the internal temperature was set to 70 ° C. Next, a hexane solution containing 0.5 g of n-butyllithium was added, and 130 g of styrene was further added, followed by polymerization for 60 minutes. The polymerization conversion rate of styrene was 100%.

Then, a mixture of 15 g of styrene and 115 g of butadiene was added and polymerization was carried out for 60 minutes.

The polymerization conversion rate of styrene and butadiene was 100%. Furthermore, this operation was repeated twice.

Next, 115 g of butadiene was added to give a polymerization conversion rate of 1
Polymerized to 00%.

Thereafter, 130 g of styrene was further added, and polymerization was carried out for 60 minutes. The polymerization addition rate was 100%.

During the polymerization, the temperature was constantly adjusted to 70 ° C. After completion of the polymerization, 2,6-di-t-butyl-p-cresol was added to the polymer solution, and then cyclohexane was removed by heating to obtain a block copolymer. The weight average molecular weight of the block copolymer was 120,000.

TR-4: (A-B) nX type, block B is a random copolymer of styrene and butadiene, a block copolymer produced by the following method.

That is, after washing and drying an autoclave with a stirrer and a jacket, cyclohexane 6 and 1 g of tetrahydrofuran were charged under a nitrogen atmosphere, and then the internal temperature was raised to 50 ° C.

Next, after adding a hexane solution containing 1 g of n-butyllithium, 380 g of styrene was added and polymerized for 60 minutes.
The polymerization conversion rate of styrene was 100%.

Then, a mixture of 20 g of styrene and 600 g of butadiene was added and polymerized for 120 minutes.

The polymerization conversion rate of styrene and butadiene was 100%.

Then, a hexane solution containing 0.66 g of tetrachlorosilane was added, and a coupling reaction was performed for 20 minutes.

During the polymerization, the temperature was constantly adjusted to 50 ° C. After completion of the polymerization, 2,6-di-t-butyl-p-cresol was added to the polymer solution, and then cyclohexane was removed by heating to obtain a block copolymer. The weight average molecular weight of the block copolymer was 120,000.

_{TR-5; A 1 -B-} A 1 type of block copolymer.

Here, A ₁ is a styrene polymer block having a bound styrene content of 40%, B is a butadiene polymer block having a bound butadiene content of 20%, and the weight average molecular weight of the copolymer is 120,000.

TR-6; A ₁ -B-A ₁ type block copolymer.

Here, A ₁ is a styrene polymer block having a bound styrene content of 20%, B is a butadiene polymer block having a bound butadiene content of 40%, and the weight average molecular weight of the copolymer is 15,000.

Flame retardant FR-1; tetrabromobisphenol A diglycidyl ether (epoxy equivalent 372), and the following compound obtained by reacting tetrabromobisphenol A with heat,
A 3: 1 weight ratio mixture with antimony trioxide powder.

R ¹ and R ² ; m; about 1.7 softening point; 118 ° C. weight average molecular weight; about 1,700 bromine content; 50% FR-2; tetrabromobisphenol A diglycidyl ether (epoxy equivalent 372), tetrabromobisphenol A and tri A mixture of the following compound obtained by reacting bromobisphenol with heating and an antimony trioxide powder in a weight ratio of 3: 1.

R ¹ and R ² ; m; about 2.8 softening point; 140 ° C. weight average molecular weight; about 3,000 bromine content; 50% FR-3; tetrabromobisphenol A (TBA)
And an antimony trioxide powder in a weight ratio of 3: 1.

Examples 1 to 8 and Comparative Examples 1 to 5 The blending recipes shown in Table 1 were respectively mixed using a Henschel mixer, and then melt-kneaded at 180 ° C. using a 44 mmφ biaxial co-rotating extruder. To produce a pellet-shaped flame-retardant masterbatch.

The flame-retardant masterbatch thus obtained and high-impact polystyrene were mixed in the proportions shown in Table 1, and test pieces were prepared by an injection molding machine and subjected to various evaluations.

The results are shown in Table 1.

As is clear from Table 1, Examples 1 to 8 use the flame retardant masterbatch of the present invention, and the objects of the present invention are obtained.

In contrast, Comparative Example 1 is an example in which the block copolymer is below the range of the present invention, and the production stability of the flame-retardant masterbatch pellets is poor.

Comparative Example 2 is an example in which polystyrene outside the scope of the present invention was used as the base polymer of the flame-retardant masterbatch,
The production stability of the flame-retardant masterbatch pellets is poor, and the properties of the pellets are extremely brittle, so that they hardly form a pellet shape.

Comparative Example 3 is an example in which high-impact polystyrene outside the scope of the present invention was used as the base polymer of the flame-retardant masterbatch, and showed the same results as Comparative Example 2.

Comparative Example 4 is an example using a block copolymer in which the amount of bound styrene exceeds the range of the present invention, and the Izod impact strength is significantly reduced.

Comparative Example 5 is an example using a block copolymer having a weight average molecular weight less than the range of the present invention, and it can be seen that the effects intended by the present invention cannot be exhibited in each evaluation item.

[Effects of the Invention] The present invention provides a flame-retardant masterbatch that can be produced at low temperature and has excellent thermal stability by using a specific block copolymer as a base polymer. When this flame-retardant masterbatch is added to the resin, the flame-retardant masterbatch has excellent dispersibility, so that it has excellent flame-retardant properties and molding appearance, as well as excellent mechanical strength and molding processability. A flame composition is obtained.

Claims (1)

[Claims] 1. A flame-retardant masterbatch containing 5 to 50% by weight of the following block copolymer and 95 to 50% by weight of a flame retardant. The block copolymer is (AB) n, (AB) nA, or (AB) nX [In the formula, A is a block mainly containing an aromatic vinyl compound, and B is mainly a conjugated diene. Block, n is 1-8
And X is a coupling agent residue], and the content of the aromatic vinyl compound is 10 to 7
An aromatic vinyl compound-conjugated diene block copolymer and / or hydrogenated product thereof, which has an amount of 0% by weight, a conjugated diene content of 90 to 30% by weight, and a weight average molecular weight of 20,000 to 500,000.