KR100572738B1 - Flameproof Styrenic Resin Composition - Google Patents

Abstract

Flame retardant styrene resin composition of the present invention (A) 80 to 97% by weight of rubber reinforced polystyrene (HIPS) resin; (B) 40 to 90% by weight of the (B ₁ ) aromatic phosphate ester compound and 10 to 60% by weight of the (B ₂ ) phosphazene compound.

Flame retardant styrene resin composition, aromatic phosphate ester compound, phosphazene compound, flame retardant HIPS resin

Description

Flame retardant styrene resin composition {Flameproof Styrenic Resin Composition}

Field of invention

The present invention relates to a styrene resin composition excellent in flame retardancy, heat resistance and fluidity. More specifically, the present invention relates to a flame retardant styrene resin composition based on a rubber-reinforced polystyrene (HIPS) resin and to which a mixture of an aromatic phosphate ester and a phosphazene compound is applied as a flame retardant.

Background of the Invention

Generally, styrene-based resins are used in almost all electronic products because of their excellent processability and mechanical properties, and are particularly used for exterior materials of electronic products. However, the styrene resin itself has a property of easy combustion and is not resistant to fire. Therefore, the styrene-based resin can be easily burned by the external ignition source, and may play a role of further spreading the fire. In view of this, the United States, Japan and Europe, etc., regulate the law to use only polymer resin that meets the flame retardant specification as an exterior material in order to ensure the safety of fire of electronic products.

The most widely known flame retardant method is to impart flame retardant properties by applying a halogen-based compound and an antimony-based compound together to the rubber-reinforced styrene resin. As the halogen-based compound, polybromodiphenyl ether, tetrabromobisphenol A, brominated substituted epoxy compound, chlorinated polyethylene and the like are mainly used. In addition, as the antimony compound, antimony trioxide and antimony pentoxide are mainly used.

However, the method of imparting flame retardancy by applying a halogen and an antimony compound together has an advantage of easily obtaining flame retardancy and hardly deteriorating physical properties. However, hydrogen halide gas generated during processing is likely to have a fatal effect on the human body. In particular, polybrominated diphenyl ethers, which are mainly halogen-based flame retardants, have a high possibility of generating very toxic gases such as dioxins and furans during combustion. Therefore, attention has been focused on flame-retardant methods that do not apply such halogen-based compounds. .

As a halogen-free flame retardant, a method of adding flame retardance to a resin composition by adding a monophosphate ester compound such as triphenyl phosphate has been studied.

In US Patent No. 4,526,917, flame retardancy was improved by using a monophosphate ester compound having TPP and mesityl groups in polyphenylene ether and styrene resin. However, in the above patent, the amount of polyphenylene ether used is 20% or more, and in such a composition, it is very difficult to achieve drop-type flame retardancy while maintaining flowability, as well as severely lowering heat resistance when using TPP. Has its drawbacks.

In the present invention, in order to overcome the above problems, by using an aromatic phosphate ester and a phosphazene compound as a flame retardant in a rubber-reinforced polystyrene (HIPS) resin that is a base resin, dropping not only excellent flame retardancy, but also excellent flow and heat resistance It has begun to develop a type flame retardant styrene resin composition.

An object of the present invention is to provide an environmentally friendly flame retardant styrene resin composition that does not generate toxic gases during processing and combustion.

Another object of the present invention is to provide a flame retardant styrene resin composition having excellent flowability.

Still another object of the present invention is to provide a dropping flame retardant styrene resin composition having excellent heat resistance.

The above and other objects of the present invention can be achieved by the present invention described below.

The thermoplastic resin composition of the present invention (A) the rubber-reinforced polystyrene (HIPS) resin of 80 to 97% by weight and (B) (B ₁₎ an aromatic phosphoric acid ester compound 40 to 90% by weight, and (B ₂₎ a cyclic phosphazene compound 10 to It consists of 3 to 20% by weight of the phosphorus compound consisting of 60% by weight, the detailed description of each of these components are as follows.

(A) Rubber reinforced polystyrene (HIPS) resin

The rubber-reinforced polystyrene (HIPS) resin used as the base resin according to the present invention is prepared by mixing and thermally polymerizing a rubber with an aromatic monoalkenyl monomer and / or an alkyl ester monomer, or polymerizing it using a polymerization initiator.

The rubber is selected from the group consisting of butadiene rubbers, isoprene rubbers, copolymers of butadiene and styrene, alkyl acrylate rubbers, and the like, and preferably 3 to 30 parts by weight, preferably 5 to 15 parts by weight.

In addition, the monomer is selected from the group consisting of aromatic monoalkenyl monomers, alkyl ester monomers of acrylic acid or methacrylic acid, 70 to 97 parts by weight, preferably 85 to 95 parts by weight of one or more monomers selected from the group. do.

The rubber-reinforced polystyrene (HIPS) resins of the present invention can be polymerized by thermal polymerization without the presence of an initiator upon polymerization, and can also be polymerized in the presence of a polymerization initiator. The polymerization initiator may be selected from at least one of an azo initiator such as a peroxide initiator consisting of benzoyl peroxide, t-butyl hydroperoxide, acetyl peroxide, cumenehydro peroxide and azobis isobutyronitrile (AIBN). Can be used.

The rubber-reinforced polystyrene (HIPS) resin may be prepared using bulk polymerization, suspension polymerization, emulsion polymerization, or a mixture thereof, and among these polymerization methods, bulk polymerization may be preferably used.

In the present invention, in order to give optimum physical properties in the blend of rubber-reinforced polystyrene (HIPS) resin and polyphenylene ether resin, the rubber particle size is preferably 0.5 to 2.0 µm.

(B) phosphorus compounds

Phosphorus-based compound used as a flame retardant in the present invention comprises 40 to 90% by weight of (B ₁ ) aromatic phosphate ester compound and 10 to 60% by weight of (B ₂ ) phosphazene compound, 3 to 20% by weight of the total resin composition Use in%. Detailed description of each of these is as follows.

(B ₁ ) Aromatic Phosphate Ester Compounds

The aromatic phosphate ester compound of the present invention is represented by the following formula (1).

[Formula 1]

Wherein R ₃ , R ₄ and R ₅ are independently of each other hydrogen or an alkyl group of C ₁ -C ₄ and X is a C ₆ -C ₂₀ aryl group or a C ₆ -C ₂₀ aryl group substituted with an alkyl group. It is derived from dialcohols of knol, hydroquinol, bisphenol-A. Also n ranges from 0 to 4. Examples of the compound represented by Chemical Formula 2 include triphenyl phosphate, tricresyl phosphate, trigylenyl phosphate, tri (2,6-dimethylphenyl) phosphate, and tri (2,4,6-trimethylphenyl) when n is 0. Phosphate, tri (2,4-dibutylbutylphenyl) phosphate, tri (2,6-dibutylbutylphenyl) phosphate, and the like, when n is 1, resorcinol bis (diphenyl) phosphate, resorcinol Bis (2,6-dimethylphenyl) phosphate, resorcinolbis (2,4-dibutylbutyl) phosphate, hydroquinolbis (2,6-dimethylphenyl) phosphate, hydroquinolbis (2,4-diary) Butylphenyl) phosphate etc. are typical examples. These aromatic phosphoric acid ester compounds may be applied alone or may be applied to each mixture.

(B ₂ ) Cyclic phosphazene compound

Cyclic phosphazene compound of the present invention is a compound having the formula (2) of the cyclic phosphazene compound of the cyclic phosphazene compound consisting of a linking group (linking group) having a -R ₂ -group Mixture.

[Formula 2]

Wherein R ₁ represents a substituent optionally selected from an alkyl group, an aryl group, an alkyl substituted aryl group, an aralkyl group, an alkoxy group, an aryloxy group, an amino group or a hydroxy group, where k and m are integers from 0 or 1 to 10 . The alkoxy group or aryloxy group of the above formula may be substituted with an alkyl group, an aryl group, an amino group, a hydroxyl group or the like. R ₂ is a C ₆ -C ₃₀ dioxyaryl or alkyl substituted C ₆ -C ₃₀ dioxyaryl group derivative, n is a number average degree of polymerization, and the average value of n is 0.3 to 3.

For example, when (n + 1) cyclic phosphazene compounds are linked to each other, an oligomeric compound of cyclic phosphazene, in which the number average degree of polymerization of the structure of Formula 2 may be represented by n Becomes

Preferred cyclic phosphazene oligomeric compounds are mixtures of cyclic phosphazene oligomeric compounds having a number average degree of polymerization of n of 0.3 to 3, in the present invention alone or in a mixture of oligomeric compounds having a degree of polymerization of 0 to 10. It may be used as, it is also preferable to use a mixture of the respective components when prepared in the polymerization process, or to use a mixture of cyclic phosphazene oligomeric compounds having a different number average degree of polymerization, respectively. In the present invention, not only the cyclic phosphazene compound is linearly connected, but also the cyclic phosphazene oligomeric compound having a branched structure may be used.

Preferred R ₁ in Formula 2 includes an alkoxy group, an aryloxy group, and the like, and more preferably a phenoxy group.

Preferred R ₂ include those derived from catechol, resorcinol, hydroquinone and bisphenylenediol represented by the following formula (3).

[Formula 3]

Wherein Y represents C _1-5 alkylene, C _1-5 alkylidene, C _5-6 cycloalkylidene, -S- or -SO _2- , z is 0 or 1.

The method for producing the cyclic phosphazene oligomeric compound used in the present invention is not particularly limited and may be prepared by the following method.

The alkyl alcohol (or aryl alcohol) is first reacted with an alkali metal hydroxide such as sodium hydroxide or lithium hydroxide to obtain an alkali metal alkylate (or alkali metal arylate). In the same manner, an alkali metal diphenolate can be obtained by reacting diols having an R ₂ group with an alkali metal hydroxide. After reacting the cyclic dichlorophosphazene compound with a mixture of an alkali metal alkylate (or alkali metal arylate) and an alkali metal diphenolate in an appropriate ratio, it is further added with an alkali metal alkylate (or alkali metal arylate). By reaction, a cyclic phosphazene oligomeric compound can be obtained.

Flame retardant thermoplastic resin composition of the present invention, in addition to the above components may be added to the anti-dropping agent, impact enhancer, inorganic additives, heat stabilizer, antioxidant, light stabilizer, pigment, and dye according to each use. The inorganic additives to be added include asbestos, glass fibers, talc, ceramics, sulfates, and the like, which may be used within the range of 0 to 50 parts by weight based on 100 parts by weight of the base resin.

The invention can be better understood by the following examples, which are intended for the purpose of illustration of the invention and are not intended to limit the scope of protection defined by the appended claims.

Example

The specifications of (A) rubber-reinforced polystyrene (HIPS) resin and (B) phosphorus-based compound used in the following Examples and Comparative Examples are as follows.

(A) Rubber reinforced polystyrene (HIPS) resin

HR-1380F manufactured by Cheil Industries Co., Ltd. was used.

(B) phosphorus compounds

(B ₁ ) As an aromatic phosphate ester compound, resorcinol (di (2,6-dimethylphenyl)) phosphate (trade name PX200, manufactured by Japan Topal Chemical Co., Ltd.) was used.

(B ₂ ) As a cyclic phosphazene compound, in Formula 2, R ₁ is a phenoxy group, k and m are 1 or 2, and n is 0, 66.5 wt%, R ₁ is a phenoxy group, and R ₂ Is derived from resorcinol, the value of k and m is 1 or 2, the value of n is 20.3% by weight, R ₁ is phenoxy, R ₂ is derived from resorcinol and the value of k and m Is 1 or 2 and the value of n is 2.9, and R ₁ is a phenoxy group, R ₂ is derived from resorcinol, the values of k and m are 1 or 2 and the value of n is 3 or more. A mixture of oligomeric compounds of cyclic phosphazene contained in 8.3% by weight was used.

Examples 1-5

Each component was added to 100 parts by weight of HIPS, which is a basic resin, in an amount as shown in Table 1 below, followed by extrusion at a temperature in the range of 200 to 280 ° C. in a conventional twin screw extruder, to prepare pellets in pellet form.

The prepared pellet was dried at 80 ° C. for 3 hours, and then injected into a 6 Oz injection machine at a molding temperature of 180-280 ° C. and a mold temperature of 40 ° C. to 80 ° C. to prepare a specimen for flame retardancy. Flame retardancy was measured at 1/8 ″ thickness according to UL94 VB standard. Flowability (MFI) was measured under 200 ℃ and 5kgf load according to ASTM D 1238. Heat resistance (VST) was measured according to ASTM D 1525. Were measured at 5 kgf load.

Comparative Examples 1 to 4

Comparative Example 1-2 was used only an aromatic phosphate ester compound as a flame retardant, Comparative Example 3-4 was carried out in the same manner as in Example except that only the phosphazene compound was added as a flame retardant.

Table 1 shows the composition and test results of each component used in Example 1-5 and Comparative Example 1-4.

Item Example Comparative Example One 2 3 4 5 One 2 3 4 (A) HIPS 100 100 100 100 100 100 100 100 100 (B) Phosphorus Compound (B ₁ ) One 2 2 3 4 5 7 - - (B ₂ ) 5 4 3 3 3 - - 5 7 UL94 Flame Retardant (1/8 ") V-2 V-2 V-2 V-2 V-2 FAIL FAIL FAIL FAIL Melt Flow Index (g / ml) 15 14 14 15 16 11 15 11 15 Vicat Softening Tempeature (℃) 84 84 84.5 84 83 86 83 86 83

From the results of Table 1 above, when the aromatic phosphate ester compound and the phosphazene compound are used as the flame retardant by mixing the flame retardant, the flame retardancy is excellent at a thickness of 1/8 "than when the aromatic phosphate ester compound or the phosphazene compound is applied alone. It was found that there was no decrease in flowability and heat resistance.

The present invention by applying an aromatic phosphate ester compound and a phosphazene compound at the same time as a flame retardant to a rubber-reinforced polystyrene (HIPS) resin that is a base resin, not only excellent flame resistance, but also provides an effect of providing a styrene resin composition excellent in heat resistance and fluidity Have

Simple modifications or changes of the present invention can be easily carried out by those skilled in the art, and all such modifications or changes can be seen to be included in the scope of the present invention.

Claims (4)

(A) 80 to 97% by weight rubber reinforced polystyrene (HIPS) resin; (B) 3 to 20% by weight of a phosphorus compound consisting of 40 to 90% by weight of (B ₁ ) aromatic phosphate ester compound and 10 to 60% by weight of (B ₂ ) phosphazene compound; Flame-retardant styrene resin composition, characterized in that consisting of. The flame-retardant styrene resin composition according to claim 1, wherein the aromatic phosphate ester compound (B ₁ ) is represented by the following general formula ( ₁ ). [Formula 1]

R ₃ , R ₄ and R ₅ are each independently hydrogen or an alkyl group of C ₁ -C ₄ ; X is a C ₆ -C ₂₀ aryl group which is substituted with a C ₆ -C ₂₀ aryl group or an alkyl group and is derived from dialshol of resorcinol, hydroquinol, bisphenol-A; n ranges from 0 to 4. The flame-retardant styrene resin composition of claim 1, wherein the phosphazene compound (B ₂ ) is represented by the following Chemical Formula 2. [Formula 2]

Wherein R ₁ represents a substituent optionally selected from an alkyl group, an aryl group, an alkyl substituted aryl group, an aralkyl group, an alkoxy group, an aryloxy group, an amino group or a hydroxy group, and k and m are 0 or an integer from 1 to 10 ; The alkoxy group or the aryloxy group of the formula may be substituted with an alkyl group, an aryl group, an amino group, a hydroxyl group or the like; R ₂ is a C ₆ -C ₃₀ dioxyaryl or alkyl substituted C ₆ -C ₃₀ dioxyaryl group derivative, n is a number average degree of polymerization, and the average value of n is 0.3 to 3. According to claim 1, wherein the resin composition is from 0 to 50 parts by weight of anti-dropping agent, impact modifier, inorganic additives, heat stabilizer, antioxidant, light stabilizer, pigment or dye based on 100 parts by weight of rubber modified styrene resin (A) The thermoplastic resin composition further comprises in a range.