KR20050049786A - Flame retardant styrene resin composition - Google Patents

Abstract

The flame-retardant styrene-based thermoplastic resin composition of the present invention (A) 100 parts by weight of rubber-reinforced polystyrene resin prepared by mixing and polymerizing rubber and aromatic monoalkenyl monomer and / or alkyl ester monomer; (B) 10 to 15 parts by weight of a brominated epoxy oligomer compound; And (C) 1 to 3 parts by weight of a flame retardant aid.

Description

Flame Retardant Styrene Resin Composition

Field of invention

The present invention relates to a styrene resin composition having flame retardancy. More specifically, the present invention relates to a styrene resin composition comprising a brominated epoxy oligomer compound and a flame retardant aid in a rubber-reinforced polystyrene resin copolymer, having flame retardancy and excellent thermal stability.

Background of the Invention

In general, styrene-based resins have good processability and mechanical strength, and are mainly used as exterior materials for electrical and electronic products. However, the resin itself is not resistant to the flame, and when the spark is ignited by an external ignition source, the resin itself acts as an energy to assist combustion, thereby continuously spreading the fire. In recent years, in the case of television among electronic products, molded products are becoming larger and thinner, and colors are also widening from dark black to pale bright colors. Therefore, the styrene-based resins applied to these fields have a problem in that not only flame retardancy but also injection molding moldability and thermal stability must be simultaneously satisfied.

Generally, the method of imparting flame retardancy to a resin may be divided into an additional flame retardant method in which a flame retardant and a flame retardant aid are added, and a polymerized flame retardant method in which a resin is prepared using a special monomer containing a flame retardant atom during polymerization. Among them, polymerized flame retardation has been studied in a pilot scale stage, but commercialized products have not been released due to high cost and difficulty in achieving flame retardancy. Therefore, most commercialized flame retardant resins are prepared by an additive flame retardant method in which a flame retardant containing halogen or phosphorus, which is an inactive element, is added during compounding.

An additional flame retardant method in which a flame retardant is added to impart flame retardancy to a styrene resin is prepared by adding at least one component selected from a halogen-containing organic compound and an antimony-containing inorganic compound to the resin. By the way, the halogen-containing organic compound is mainly bromine or chlorine compound, when added to the styrene resin is very excellent in flame retardancy, but causes serious degradation in the overall physical properties. In addition, there is a problem that the thermal stability is lowered. Therefore, in manufacturing a flame retardant resin, a technique of minimizing physical properties and side effects while maintaining excellent flame retardancy is very important.

Conventional UL94 V-2 products are designed to cause drips of the resin in a short time during combustion by promoting decomposition of the resin by decomposition of the flame retardant. Due to this feature, the flame retardant is designed to cause thermal decomposition quickly.However, this characteristic causes the decomposition of the flame retardant at the normal processing temperature of the resin, which lowers the thermal stability of the resin itself, resulting in poor silver streak. Or, there is a drawback of thermal discoloration from bright to dark red.

Conventional melt type aliphatic halogen flame retardants mainly used to maintain the flame retardancy of UL94 V-2 products include tetrabromo bisphenol A bis (2,3-dibromopropyl ether) compounds, which are aliphatic The flame retardant effect is good because it has a structure, but injection molding at a high temperature to process a large thin-film molded article has a disadvantage that a large problem in thermal stability occurs. Therefore, in order to increase the thermal stability while maintaining the flame retardancy of the UL94 V-2 product, the selection of the flame retardant is important, as well as the combination of the rubber-reinforced polystyrene resin copolymer with the flame retardant and the flame retardant aid.

On the other hand, the present inventors, through the combination of the flame retardant brominated epoxy oligomer and the flame retardant aid in the rubber-reinforced polystyrene resin copolymer in order to overcome the above problems, while maintaining the flame resistance of the UL94 V-2 product and thermal stability during injection molding It has led to the development of flame-retardant thermoplastic resin compositions suitable for injection molded articles of large products, especially large televisions, by greatly improving the flow characteristics.

An object of the present invention is to provide a flame-retardant styrene-based resin composition excellent in injection molding molding properties to be applied to large thin-film molded article.

Another object of the present invention is to enable injection processing at low temperature by improving the fluidity of the flame retardant styrene resin composition.

Still another object of the present invention is to provide a flame retardant styrene resin composition capable of making a molded article having a good appearance by using flame retardant properties.

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

Summary of the Invention

The flame-retardant styrene-based thermoplastic resin composition of the present invention (A) 100 parts by weight of rubber-reinforced polystyrene resin prepared by mixing and polymerizing rubber and aromatic monoalkenyl monomer and / or alkyl ester monomer; (B) 10 to 15 parts by weight of the brominated epoxy oligomer compound; And (C) 1 to 3 parts by weight of a flame retardant aid.

Hereinafter, the detailed description of each component of the flame-retardant styrene resin composition of the present invention is as follows.

Detailed Description of the Invention

(A) Rubber reinforced polystyrene resin

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

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

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

The resin may be prepared by bulk polymerization using one or more initiators selected from benzoyl peroxide, t-butyl hydroperoxide, acetyl peroxide, and cumene hydroperoxide.

The rubber-reinforced polystyrene resin may be prepared using a bulk polymerization, suspension polymerization, emulsion polymerization or a mixture thereof, in the embodiment of the polymerization method used a rubber-reinforced polystyrene resin produced by the bulk polymerization method.

(B) brominated epoxy oligomers

In the present invention, by using a brominated epoxy oligomer to improve the fluidity while maintaining the flame retardancy of UL94 V-2 products, it is possible to injection molding at low temperatures to improve the physical stability. In addition, a molded article having a good appearance can be manufactured by using a brominated epoxy oligomer having excellent appearance characteristics than a flame retardant having an aliphatic structure.

The brominated epoxy oligomer (B) is a material represented by the following formula (1).

[Formula 1]

The brominated epoxy oligomer (B) is preferably used 10 to 15 parts by weight based on 100 parts by weight of the rubber-reinforced polystyrene resin (A). If less than 10 parts by weight is added, the flame retardant effect is insufficient, and when used in excess of 15 parts by weight is not preferable because it impairs the balance of mechanical properties.

(C) flame retardant supplements

The flame retardant adjuvant is a combination selected from antimony trioxide, paraffin chloride, and potassium sulfone sulfate, It is added to further improve the flame retardancy of the bromine flame retardant. The antimony trioxide is preferably used 1 to 3 parts by weight based on 100 parts by weight of the base resin (A) of the present invention. If the amount is less than 1 part by weight, a sufficient flame retardant effect cannot be obtained. If the content is more than 3 parts by weight, the balance of the physical properties of the resin composition is impaired, which is not preferable.

In addition to the above components, the flame retardant thermoplastic resin composition of the present invention may add inorganic additives, antioxidants, other light stabilizers, pigments, and dyes in required amounts depending on their respective uses.

The resin composition of the present invention can be used for molding various products, and in particular, it has high fluidity and flame retardancy, so that molding at low temperature is possible, and housing manufacturing of all V-2 electric and electronic products requiring flame retardancy and appearance characteristics is required. Suitable for

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

In Examples 1 to 3 and Comparative Examples 1 to 5 of the present invention, (A) rubber-reinforced polystyrene resin was used as HR-1360 of Cheil Industries, and (B) a brominated epoxy represented by Formula 1 as an aromatic halogen flame retardant. An oligomer was used, and (B ') tetrabromo bisphenol A bis (2,3-dibromopropyl ether) compound represented by the following Chemical Formula 2 was used as an aliphatic halogen flame retardant, and (C) trioxide was used as a flame retardant aid. Antimony was used.

[Formula 2]

Examples 1 to 3

The resin composition obtained by mixing according to the composition of each component of the composition shown in Table 1 was uniformly mixed with a Tumbler mixer, then extruded with a twin screw extruder to produce pellets, and from the prepared pellets to injection molding 1/8 "thick flame retardant specimens, physical properties specimens and thermal stability test specimens were prepared and evaluated.

Comparative Examples 1 to 5

Comparative Examples 1 to 5 were prepared in the same manner as in Examples 1 to 3 except that the composition of each component was changed as described.

ingredient Example Comparative Example One 2 3 One 2 3 4 5 (A) Rubber reinforced styrene resin 2 types 100 100 100 100 100 100 100 100 (B) brominated epoxy oligomer 15 13 10 - 17 8 15 10 (B ') tetra bromo bisphenol A bis (2,3-dibromopropyl ether) compound - - - 13 - - - - (C) antimony trioxide 3 2 One 3 3 One 5 0.5

   (Unit is by weight)

Measurement of the flame retardancy of the resin composition prepared by the above method was carried out according to the UL-94 determination test method. For reference, the V-2 grade is given to resins that extinguish a flame by dropping it on the specimen within a specified time when the specimen is ignited. In order to evaluate the mechanical properties, a notch was made in a 1/8 "IZOD specimen by ASTM D256 evaluation method. The evaluation of the appearance was determined by injection molding using an appearance mold. 10 minutes in the cylinder cylinder 250 ℃ after measuring the degree of thermal stability appearing on the specimen during injection molding was evaluated.

Table 2 shows the physical properties of the resins prepared in Examples 1-3 and Comparative Examples 1-5. Examples 1-3 are the case where a flame retardant and a flame retardant adjuvant are used in the range by this invention, and Comparative Examples 1-5 are the case where it used out of the said range.

ingredient Example Comparative Example One 2 3 One 2 3 4 5 (1) Flame retardant V-2 V-2 V-2 V-2 V-2 Fail V-2 Fail (2) Total burning time (seconds) 120 130 150 145 115 200 115 200 (3) Injection stay result ○ ◎ ○ × ◎ ◎ △ ○ (4) mechanical properties 9.8 10.0 10.5 9.0 8.5 10.8 9.2 10.7 Note: (3) Thermal stability after 10 minutes of injection retention at 250 ° C.-◎ (very good), ○ (good), △ (normal), × (poor) (4) ASTM D256 Izod IZOD Impact Strength

From the results of Table 2, the halogen-based flame retardant brominated epoxy oligomer (B) and the flame retardant adjuvant antimony trioxide (C) was used in the composition range of the present invention was excellent in flame retardancy, appearance characteristics and mechanical properties all . Comparative Example 1 using a large amount of tetra bromo bisphenol A bis (2,3-dibromopropyl ether) compound was excellent in flame retardancy, but the appearance characteristics were not good. In Comparative Examples 2 and 4, the mechanical properties and appearance characteristics tend to be slightly lowered due to the excessive effects of the flame retardant and antimony trioxide. In Comparative Examples 3 and 5, the flame retardant problem occurs due to the lack of the flame retardant and antimony trioxide.

The present invention uses a combination of a brominated epoxy oligomer compound and antimony trioxide in combination with a rubber-reinforced polystyrene resin copolymer, thereby improving the fluidity and enabling injection molding at low temperatures, as well as providing a thermoplastic resin composition having excellent flame retardancy, appearance and mechanical properties. Has the effect of providing.

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 (3)

(A) 100 parts by weight of rubber-reinforced polystyrene resin prepared by mixing and polymerizing rubber with aromatic monoalkenyl monomer and / or alkyl ester monomer; (B) 10 to 15 parts by weight of a brominated epoxy oligomer compound which is a halogen-based flame retardant represented by Formula 1; And [Formula 1] (C) 1-3 parts by weight of flame retardant aids; Flame-retardant styrene resin composition, characterized in that consisting of. The rubber of claim 1, wherein the rubber of the polystyrene resin (A) comprises 5 to 15 parts by weight of a rubber selected from the group consisting of butadiene rubber, isoprene rubber, a copolymer of butadiene and styrene, and an alkyl acrylate rubber. Flame retardant styrene resin composition. The flame retardant styrene resin composition according to claim 1, wherein the flame retardant auxiliary agent is one or more selected from the group consisting of antimony trioxide, paraffin chloride, and potassium sulfon sulfate.