KR20040060030A - Flameproof Thermoplastic Resin Composition - Google Patents

Abstract

PURPOSE: Provided is a flame retardant thermoplastic resin composition, which has stability against fire, excellent heat resistance, mechanical strength and moldability, and is environmental-friendly due to the absence of halogen-containing flame retardant compounds. CONSTITUTION: The flame retardant thermoplastic resin composition comprises: (A) 100 parts by weight of a rubber-modified styrene-based resin composed of (a1) 20-100 wt% of a graft copolymer resin obtained by graft polymerization of 5-65 wt% of a rubbery polymer, 30-94 wt% of an aromatic vinyl monomer, 1-20 wt% of a monomer which can be copolymerized with the aromatic vinyl monomer and 0-15 wt% of a monomer for supplementing processability and heat resistance, and (a2) 0-80 wt% of a copolymer resin obtained by copolymerization of 60-90 wt% of an aromatic vinyl monomer, 10-40 wt% of a monomer which can be copolymerized with the aromatic vinyl monomer and 0-30 wt% of a monomer for supplementing processability and heat resistance; and (B) 1-15 parts by weight of a diphosphate compound having a cyclic alkyl group.

Description

Flameproof Thermoplastic Resin Composition

Field of invention

The present invention relates to a styrene resin composition having excellent environmental friendliness and excellent flame retardancy. More specifically, the present invention is not only excellent in flame retardancy, but also excellent in heat resistance, mechanical strength and moldability by using a diphosphate ester compound and an aromatic phosphate ester compound having a cyclic alkyl group as a flame retardant in a rubber-modified styrene resin. It relates to a thermoplastic resin composition.

Background of the Invention

In general, rubber-modified styrene-based resins have a good processability, excellent physical properties, particularly impact strength and excellent appearance have been used in a variety of applications, such as electrical and electronic products and office equipment. However, the rubber modified styrene resin itself has a disadvantage in that it is combustible when used in a product that emits heat such as a computer or a fax machine. Therefore, methods for imparting flame retardancy have been developed to prevent combustibility of rubber-modified styrene resins.

A flame retardant technique commonly used to impart flame retardancy to a conventional rubber modified styrene resin composition is to mix a halogen compound which is a flame retardant with a rubber modified styrene resin composition. Commonly used halogen-based compounds include polybromodiphenyl ether, tetrabromobisphenol A, and bromine substituted epoxy compounds. It is well known to increase the flame retardancy of a resin by using an antimony compound together with these halogen compounds.

However, as described above, the method of imparting flame retardancy using a halogen compound and an antimony compound may cause the halogen compound used as a main flame retardant to volatilize during processing to generate hydrogen halide gas, which may corrode the mold, and the hydrogen halide gas generated during combustion. Is likely to have a fatal effect on the human body. Among them, polybrominated diphenyl ethers, which are the mainstay of halogen-based flame retardants, have a high possibility of generating very toxic gases such as dioxins and difurans during combustion. Therefore, halogen-based compounds have not been used in Europe since the mid 80s. Interest in flame retardant methods.

U.S. Patent No. 3,639,506 discloses an example in which a mono aromatic phosphate ester is applied to a blend of a styrene resin and a polyphenylene ether resin. However, the triphenyl phosphate used herein has a high heat resistance deterioration and a high volatility, so that liquid foreign substances are generated during the molding process of the resin and cause a cracking of the juice.

Japanese Patent No. Hei 7-043769 discloses dropping flame retardancy when applied to rubber-reinforced styrene resin (HIPS) by introducing a substituent having 12 to 25 carbon atoms to a phenyl group of triphenyl phosphate to solve the problem of volatility. It is starting.

U.S. Patent No. 4,073,767 discloses that phosphorus compounds having a cyclic alkyl structure are effective flame retardants for polyurethanes, polyesters, and polyamides, and Japanese Patent No. 5-1079 prevents the lowering of heat resistance of triphenyl phosphate and improves its volatility. A diphosphate ester structure having an aromatic phenyl group as a linking group is disclosed.

Accordingly, the present inventors have applied a diphosphate ester flame retardant having a cyclic alkyl group to a rubber-modified styrenic resin in order to solve the problem of volatility without deteriorating heat resistance, thereby achieving environmentally friendly dropping flame retardancy, forming moldability, heat resistance and It is to develop a thermoplastic resin composition excellent in mechanical properties.

An object of the present invention is to provide a flame retardant thermoplastic resin composition that is stable against fire.

Another object of the present invention is to provide an environmentally friendly thermoplastic resin composition by using a diphosphate ester compound having a cyclic alkyl group as a flame retardant, without using a halogen compound that causes environmental pollution during processing or combustion of the resin as a flame retardant. It is for.

Still another object of the present invention is to provide a thermoplastic resin composition having excellent heat resistance.

Still another object of the present invention is to provide a thermoplastic resin composition having excellent mechanical strength.

Another object of the present invention is to provide a thermoplastic resin composition excellent in moldability.

The above and other objects of the present invention can be achieved by the present invention described below. Hereinafter, the content of the present invention will be described in detail.

The flame-retardant thermoplastic resin composition of the present invention (A) (a ₁ ) 5 to 65% by weight of the rubbery polymer 30 to 94% by weight of the aromatic vinyl monomer, 1 to 20% by weight of the monomer copolymerizable with the aromatic vinyl monomer And 20 to 100% by weight of the graft copolymer resin graft-polymerized by adding 0-15% by weight of a monomer which adds processability and heat resistance, and (a ₂ ) 60 to 90% by weight of the aromatic vinyl monomer. 100 parts by weight of a rubber-modified styrene resin comprising 10 to 40% by weight of a copolymerizable copolymer and 0 to 80% by weight of a copolymer resin copolymerized by adding 0 to 30% by weight of a monomer that adds processability and heat resistance, and (B A) 1 to 15 parts by weight of a diphosphate ester compound having a cyclic alkyl group, and optionally 0 to 10 parts by weight of (C) an aromatic phosphate ester compound. Can be.

Hereinafter, the detailed description of each of these components is as follows.

(A) Rubber modified styrene resin (ABS resin)

The rubber-modified resin used in the present invention refers to a polymer in which a rubbery polymer is dispersed in the form of particles in a matrix (continuous phase) made of a vinyl aromatic polymer and copolymerized with an aromatic vinyl monomer in the presence of a rubbery polymer. It is produced by adding and polymerizing a vinyl monomer as much as possible.

Such rubber-modified styrene-based resins can be produced by known polymerization methods such as emulsion polymerization, suspension polymerization, and bulk polymerization, and are usually produced by mixed extrusion of graft copolymer resin and copolymer resin. In the case of bulk polymerization, rubber modified styrene resins are produced by only one step reaction without preparing graft copolymer resins and copolymer resins, but in any case, the rubber content of the final rubber modified styrene resin components 5-30 weight part with respect to a suitable thing.

Examples of such resins include acrylonitrile-butadiene-styrene copolymer resins (ABS), acrylonitrile-acryl rubber-styrene copolymer resins (AAS), acrylonitrile-ethylenepropylene rubber-styrene copolymer resins, and the like. .

Examples of the above resin can be applied to the graft resin alone or in combination of the graft copolymer resin and the copolymer resin, and is preferably blended in consideration of their compatibility.

(a ₁ ) Styrene-acrylonitrile-containing graft copolymer resin

Examples of the rubber used for the graft copolymer resin include diene rubbers such as polybutadiene, poly (styrene-butadiene) and poly (acrylonitrile-butadiene), saturated rubbers which are hydrogenated with the diene rubber, isoprene rubber, And acrylic rubbers such as polybutylacrylic acid, and ethylene-propylene-diene monomer terpolymer (EPDM). Of these, especially diene rubber is preferred, and more preferably butadiene rubber is suitable. The content of rubber is suitably 5 to 65% by weight of the graft copolymer resin.

As the aromatic vinyl monomer in the graft polymerizable monomer mixture, styrene, α-methylstyrene, p-methylstyrene, or the like may be added. Of these, styrene is most preferred, and one or more monomers copolymerizable with the aromatic vinyl monomers are introduced and applied thereto. As a monomer which can be introduced, vinyl cyanide-based compounds such as acrylonitrile and unsaturated nitrile-based compounds such as methacrylonitrile are preferable.

In the present invention, the gypsum copolymer is composed of 5 to 65% by weight of the rubbery polymer, 30 to 94% by weight of the aromatic vinyl monomer, and 1 to 20% by weight of the monomer copolymerizable to the aromatic vinyl monomer. Added and graft copolymerized.

In the preparation of the graft copolymer, monomers such as acrylic acid, methacrylic acid, maleic anhydride, and N-substituted maleade may be further added to give graft polymerization properties such as processability and heat resistance. The amount added is in the range of 0 to 15% by weight of the graft copolymer resin as a whole.

In consideration of the impact strength and appearance when preparing the graft copolymer, the average size of the rubber particles is suitably in the range of 0.1 to 4 μm.

(a ₂ ) Copolymer Resin

The copolymer resin is prepared according to the monomer ratio and compatibility of the graft copolymer prepared in the above composition except for rubber, and the components thereof are as follows.

As the aromatic vinyl monomer to be copolymerized, styrene, α-methyl styrene, p-methyl styrene, and the like may be added. Of these, styrene is most preferred, and the amount of the aromatic vinyl monomer in the total copolymer resin is 60 to 90% by weight. Is preferred.

One or more types of monomers copolymerizable with the aromatic vinyl monomers are introduced into the copolymer resin. The copolymerizable monomer is preferably a vinyl cyanide compound such as acrylonitrile or an unsaturated nitrile compound such as methacrylonitrile. Its monomers are introduced at 10 to 40% by weight of the total component of the copolymer resin.

The copolymer resin may be copolymerized by adding 0 to 30% by weight of monomers such as acrylic acid, methacrylic acid, maleic anhydride, and N-substituted maleade in order to impart properties such as processability and heat resistance.

In the rubber-modified styrene resin (A), the styrene-acrylonitrile-containing graft copolymer resin (a ₁ ) is 20 to 100% by weight and the styrene-acrylonitrile-containing copolymer resin (a ₂ ) is 0 to 80% by weight. %to be.

(B) diphosphate ester compound having a cyclic alkyl group

The diphosphate ester compound having a cyclic alkyl group of the present invention is represented by the following formula (1).

[Formula 1]

R ₁ and R ₂ 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.

Representative compounds of Formula 1 include bisphenol-A (di (trimethylene)) phosphate, bisphenol-A (di (2,2'-dimethyltrimethylene)) phosphate, and the like. These compounds may be applied alone or as a mixture. It is possible.

In the present invention, the diphosphate ester compound having the cyclic alkyl group is used in an amount of 1 to 15 parts by weight based on 100 parts by weight of the rubber modified styrene resin.

(C) Aromatic Phosphate Ester Compounds

The aromatic phosphate ester compound used in the present invention is represented by the following formula (2).

[Formula 2]

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 1 to 4.

When n is 1, the compound corresponding to Formula 2 is resorcinol bis (diphenyl) phosphate, resorcinol bis (2,6-dimethylphenyl) phosphate, resorcinol bis (2,4-dibutyl butylphenyl Phosphate, hydroquinolbis (2,6-dimethylphenyl) phosphate, hydroquinolbis (2,4-dibutylbutylphenyl) phosphate and the like are typical examples. These aromatic phosphate ester compounds may be applied alone or in each mixture.

In the present invention, in addition to the above components, thermal stabilizers, antioxidants, light stabilizers, organic and inorganic pigments, dyes and inorganic fillers may be added according to their respective uses. The inorganic additives to be added include asbestos, glass fibers, talc, ceramics and sulfates, which are used in an amount of 0 to 30 parts by weight based on 100 parts by weight of the base resin of the present invention.

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 the diphosphate ester compound having (A) rubber-modified styrene resin and (B) cyclic alkyl group used in the following Examples and Comparative Examples are as follows.

(A) Rubber modified styrene resin

(a ₁ ) Styrene-acrylonitrile-containing graft copolymer resin

50 parts by weight of a solid of butadiene rubber latex, 36 parts by weight of styrene as a graft polymerized monomer, 14 parts by weight of acrylonitrile, and 150 parts by weight of deionized water, and 1.0 parts by weight of potassium oleate and cumene to the total solids of the mixture. 0.4 parts by weight of hydroperoxide, 0.2 parts by weight of mercaptan-based chain transfer agent, 0.4 parts by weight of glucose, 0.01 parts by weight of iron sulfate hydrate, and 0.3 parts by weight of pyrophosphate sodium salt were added to maintain 75 ° C for 5 hours to complete the reaction. Graft copolymer (g-ABS) latex was prepared. 0.4 parts by weight of sulfuric acid was added to the prepared resin composition solid and solidified to prepare a graft copolymer resin (g-ABS) in powder form.

(a ₂ ) Styrene-acrylonitrile-containing copolymer resin

Room temperature was added by adding 75 parts by weight of styrene, 25 parts by weight of acrylonitrile, 120 parts by weight of deionized water, 0.2 parts by weight of azobisisobutyronitrile, 0.4 parts by weight of tricalcium phosphate, and 0.2 parts by weight of mercaptan-based chain transfer agent. The styrene / acrylonitrile copolymer resin (SAN) was prepared by increasing the temperature to 80 ° C. for 90 minutes and maintaining the temperature at this temperature for 180 minutes. This was washed with water, dehydrated and dried to prepare a powdered styrene / acrylonitrile copolymer resin (SAN). The weight average molecular weight of the produced styrene / acrylonitrile copolymer resin was about 80,000 to 100,000.

(B) diphosphate ester compound having a cyclic alkyl group

Bisphenol-A (di (2,2'-dimethyltrimethylene)) phosphate [product name XP-3010] of Albemarle, USA was used. It is a compound having a melting point of 180-184 ° C.

(C) Aromatic Phosphate Ester Compounds

(C ₁ ) Lesosinolbis (2,6-dimethylphenyl) phosphate [trade name PX200] was used.

(C ₂ ) Triphenyl phosphate (TPP) from Japan Co., Ltd. was used as aromatic monophosphate.

Example 1-3

Each component was added to the content shown in Table 1 below and extruded at a temperature range of 180 ~ 250 ℃ in a conventional twin screw extruder to prepare a pellet. The prepared pellets were dried at 80 ° C. for 3 hours, and then injected in a 6 Oz injection machine under conditions of a molding temperature of 180 to 280 ° C. and a mold temperature of 40 to 80 ° C. to prepare a physical specimen. The physical properties were measured by the following method.

(1) Flame retardant: Flame retardant was measured at 1/12 ", 1/8" thickness according to UL 94 VB flame retardant regulation.

(2) notched Izod impact strength: measured in ASTM 256A condition at 1/8 "thickness.

(3) Heat resistance: measured at 5 kgf load in accordance with ASTM D 1525.

(4) Volatilization amount: The resin pellets were measured using a Thermogravimetric Analysis Test while being allowed to stand for 10 minutes while flowing nitrogen at 250 ° C. under isothermal conditions.

Comparative Example 1-2

Comparative Example 1 was added to the aromatic monophosphate instead of the aromatic phosphate ester compound of the present invention as a flame retardant, Comparative Example 2 was prepared in the same manner as in Example except that only aromatic monophosphate was used as a flame retardant. .

The composition and physical properties of the resin prepared in Example 1-3 and Comparative Example 1-2 are shown in Table 1 below.

Item Example Comparative Example One 2 3 One 2 (A) Rubber modified styrene resin (a ₁ ) 30 30 30 30 30 (a ₂ ) 70 70 70 70 70 (B) XP3010 4 6 3 3 - (C ₁ ) PX200 - - 3 - - (C ₂ ) TPP - - - 3 6 UL94 flame retardant, (1/12 ") V2 V2 V2 V2 V2 UL94 flame retardant, (1/8 ") V2 V2 V2 V2 Fail Izod Impact Strength 1/8 " 21 19 20 21 17 Heat resistance degree (℃) 95 93 94 85 79 Volatility (250 degrees) 0.4% 0.6% 0.5% 2.5% 5%

From the results of Table 1, the composition prepared using a diphosphate ester compound having a cyclic alkyl group as a flame retardant was excellent dropping flame retardancy, there is no reduction in impact strength and heat resistance, and the amount of volatilization does not cause liquid phase problems And it was found. In addition, when the aromatic monophosphate ester is used as a flame retardant, not only the flame retardancy is lowered, but also the heat resistance is severely lowered, and the volatilization amount is high.

The present invention is environmentally friendly and excellent in flame retardancy and heat resistance and mechanical impact strength by applying a diphosphate ester compound having a cyclic alkyl group and optionally an aromatic phosphate ester compound as a flame retardant to a base resin made of rubber-modified styrene resin. And providing a resin composition excellent in moldability.

Simple modifications or variations of the invention may be readily made by those skilled in the art, and all such modifications or changes may be considered to be included within the scope of the present invention.

Claims (10)

(A) (a ₁ ) 30 to 94% by weight of an aromatic vinyl monomer, 1 to 20% by weight of a monomer copolymerizable with the aromatic vinyl monomer, and a monomer which adds processability and heat resistance to 5 to 65% by weight of a rubbery polymer. 20 to 100% by weight of the graft copolymer resin graft-polymerized by adding 0 to 15% by weight and (a ₂ ) 60 to 90% by weight of the aromatic vinyl monomer 10 to 10 monomers copolymerizable with the aromatic vinyl monomer 100 parts by weight of a rubber-modified styrene resin composed of 0 to 80% by weight of a copolymer resin copolymerized by adding 40% by weight and 0 to 30% by weight of a monomer which adds processability and heat resistance; And (B) 1 to 15 parts by weight of the diphosphate ester compound having a cyclic alkyl group; Flame-retardant thermoplastic resin composition, characterized in that consisting of. The flame retardant thermoplastic resin composition according to claim 1, wherein the resin composition further comprises 0 to 10 parts by weight of (C) an aromatic phosphate ester compound based on 100 parts by weight of (A). The rubbery polymer according to claim 1, wherein the rubbery polymer is selected from the group consisting of diene rubbers, saturated rubbers hydrogenated with diene rubbers, isoprene rubbers, acrylic rubbers, and ethylene / propylene / diene monomer terpolymers (EPDM). Flame retardant thermoplastic resin composition, characterized in that. The flame retardant thermoplastic resin composition of claim 1, wherein the aromatic vinyl monomer is selected from the group consisting of styrene, α-methylstyrene, and p-methylstyrene. The flame retardant thermoplastic resin composition of claim 1, wherein the monomer copolymerizable with the aromatic vinyl monomer is selected from a vinyl cyanide compound and an unsaturated nitrile compound. The flame retardant thermoplastic resin composition of claim 1, wherein the monomer adding processability and heat resistance is selected from the group consisting of acrylic acid, methacrylic acid, maleic anhydride, and N-substituted maleade. The method of claim 1 wherein the rubber modified styrene resin (A) is acrylonitrile / butadiene / styrene copolymer resin (ABS), acrylonitrile / acrylic rubber / styrene copolymer resin (AAS), acrylonitrile / ethylene propylene A flame retardant thermoplastic resin composition, characterized in that it is selected from the group consisting of rubber / styrene copolymer resins (AES). The flame retardant thermoplastic resin composition according to claim 1, wherein the diphosphate ester compound (B) having the cyclic alkyl group is represented by the following general formula (1). [Formula 1] R ₁ and R ₂ 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. The flame-retardant thermoplastic resin composition of claim 2, wherein the aromatic phosphate ester compound (C) is represented by the following Chemical Formula 2. [Formula 2] 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 1 to 4. The flame retardant thermoplastic resin composition of claim 1, wherein the resin composition further comprises 0 to 30 parts by weight of an antidripping agent, a heat stabilizer, an antioxidant, a light stabilizer, a compatibilizer, a pigment, a dye, and / or an inorganic filler. .