KR960012457B1 - Flame-retardant thermoplastic resin composition - Google Patents

Abstract

The resin composition is excellent in mechanical strength and flame retardance which can be used as housing for electrics and electronics. The resin composition is made by employing as a base resin, 20 to 70 wt. % of polycarbonate, 20 to 70 wt. % of acrylonitrile-butadien-styrene graft copolymer resin and 10 to 20 wt. % of bromide system epoxy resin of the formula(I), as well as containing, per 100 parts by weight of said base resin composition, 0.3 to 1.0 parts by weight of tefron 6 resin, 0.1 to 1.0 parts by weight of polyethylene system wax and 0.1 to1.0 parts by weight of thio-di-profionate and 4,4-thio-bis(6-tertiary-butyl-3 methylphenol) respectly.

Description

Flame Retardant Thermoplastic Composition

The present invention relates to a flame retardant thermoplastic resin composition, and more particularly, to a polycarbonate (hereinafter, referred to as PC) resin, an acrylonitrile-butadiene-styrene graft copolymer (hereinafter referred to as ABS), and a bromine epoxy resin. Teflon 6 resin as a driping agent, polyethylene-based wax as lubricant, di-stearyl-thio-di-propionate as antioxidant, and 4,4'-dio-bis (6-tertiary-) Butyl-3-methylphenol) relates to a flame-retardant thermoplastic resin composition that is excellent in mechanical strength and flame retardancy can be usefully used in the housing of electrical and electronic products.

Conventionally, the blend composition of PC and ABS has been widely used in combination with the excellent mechanical properties of PC and the processability of ABS, and studies on the flame retardancy required for the use of such resins in housings such as electronic products It is also actively underway.

As an example of the improved resin composition as part of such research and development, US Patent No. 3,852,393 mentions a technique for imparting flame retardancy by adding a halogen compound and antimony trioxide to a PC and an ABS resin composition. Since the added antimony trioxide has a problem of reducing the overall physical properties by acting to cut the ester linkage group of the PC during the extrusion and molding process, bromine contains relatively stable bromine in the halogen element and has a small decrease in the overall physical properties of the composition. Recently, research on the epoxy resin has been actively conducted.

However, this also has a problem that the improvement of the drifting that causes the flame retardant weakening during combustion is not enough.

Accordingly, the present inventors have made efforts to solve the above problems. As a result, bromine-based epoxy resins as flame retardants in PC and ABS resins, Teflon 6 resins as dripping improvers in combustion, polyethylene waxes as lubricants, as di-stearyl- By using thio-di-propionate and 4,4'-thio-bis (6-tertary-butyl-3-methylphenol), thermoplastic resins not only having excellent mechanical properties and heat resistance but also excellent flame retardancy, particularly dripping resistance The present invention has been completed by preparing the composition.

An object of the present invention is to provide a thermoplastic resin composition having excellent mechanical strength and excellent flame retardancy.

Hereinafter, the present invention will be described in detail.

The present invention relates to a flame-retardant thermoplastic resin composition comprising a polycarbonate, an acrylonitrile-butadiene-styrene graft copolymer, and a bromine epoxy resin as a basic resin composition, wherein the polycarbonate (PC) resin is 20 to 70% by weight, atrylonitrile Teflon 6 resin 0.3 to 100 parts by weight of the basic resin composition composed of 20 to 70% by weight of butadiene-styrene (ABS) graft copolymer resin and 10 to 20% by weight of bromine epoxy resin represented by the following structural formula (I): -1.0 parts by weight, 0.1-1.0 parts by weight polyethylene wax, and thio-di-propionate and 4,4'-thio-bis (6-tert-butyl-3-methylphenol) as antioxidants, respectively. It is characterized by containing 0.1-1.0 weight part.

Wherein n is an integer of 100 to 150.

Referring to the present invention in more detail as follows.

The present invention is composed of a PC resin, ABS resin and bromine epoxy resin as a main component, and a thermoplastic resin composition having excellent mechanical strength and excellent flame retardancy by adding Teflon 6 resin as a dripping agent and polyethylene wax and antioxidant as a lubricant. In the present invention, the PC resin used in the present invention is used at 20 to 70% by weight in the basic resin composition, the content is less than 20% by weight impact resistance and heat resistance is lowered, if it exceeds 70% by weight of the resin Flowability and processability will be poor.

In addition, the PC resin has a viscosity average molecular weight of 18,000 to 30,000 by methylene chloride. When the viscosity average molecular weight is 18,000 or less, the mechanical properties are extremely low, and when it exceeds 30,000, the processability is poor. It causes problems such as increasing the defective rate during processing.

In addition, ABS resin is used in the base resin composition of 20 to 70% by weight, the content of less than 20% by weight does not improve the impact resistance and processability, and exceeds 70% by weight of the heat resistance and mechanical properties The ABS resin used in the present invention is composed of 5 to 7% by weight of diene rubber, 20 to 70% by weight of aromatic vinyl compound, and 10 to 50% by weight of vinyl cyanide compound. It is preferable in terms of preventing heat resistance.

As the diene rubber constituting the ABS resin, polybutadiene, butadiene-styrene copolymer or butadiene-acrylic copolymer can be used, and as an aromatic vinyl compound, styrene, alpha-methylstyrene, dimethyl styrene or vinyltoluene, cyan compound As the acrylonitrile or methyl methacrylonitrile can be used.

In addition, the bromine-based epoxy resin of the formula (I) is used in the amount of 10 to 20% by weight of the base resin, if the content is less than 10% by weight can not expect a sufficient flame retardant effect and exceed 20% by weight In this case, there is no synergistic effect of flame retardancy on the amount added. If the repeating unit (n) in the structural formula (I) is less than 100, there is a problem that the mechanical strength of the resin composition is lowered, and if it exceeds 150, the mechanical strength of the resin composition is excellent but the flowability is deteriorated.

Meanwhile, the Teflon 6 resin used as the anti-driping agent in the present invention is used in an amount of 0.3 to 10 parts by weight with respect to 100 parts by weight of the base resin composed of PC, ABS, and bromine epoxy resin, and the amount of addition thereof is 0.3% by weight. If it is less than the part%, the improvement of the dripping property at the time of combustion is not achieved, and when it exceeds 1.0 weight%, it will cause the extruder load increase at the time of extrusion, and the general physical properties of a resin composition will become bad.

In addition, the polyethylene wax used as a lubricant may have a molecular weight of 1,000 to 4,000 but using more than 2,000 may prevent thermal decomposition during the processing process, 0.1 to 1.0 parts by weight relative to 100 parts by weight of the base resin When used as, the content is less than 0.1 parts by weight, there is no effect of improving the releasability at the time of injection and melt flow of the resin, and when the content exceeds 1.0 parts by weight, the heat resistance is lowered. As the antioxidant, di-stearyl-thio-di-propionate is used in an amount of 0.1 to 1.0 parts by weight based on 100 parts by weight of the base resin, and if the content is 0.1 parts by weight or less, the thermal stability of the resin If this becomes poor and exceeds 1.0 parts by weight, no increase in effect due to the excessive addition amount is expressed, and another antioxidant used in the present invention is 4,4'-thio-di (6-tertiary-). Butyl-3-methylphenol) is used in an amount of 0.1 to 1.0 parts by weight based on 100 parts by weight of the basic resin. If the content is less than 0.1 parts by weight, mechanical properties due to oxidation of the resin during processing are caused. If it exceeds 1.0 weight part, since an increase of an addition effect cannot be expected, it is preferable to use in the said range of each component.

In order to obtain the flame retardant thermoplastic resin composition according to the present invention using the resin composition as described above, the composition mixture is extruded with a melt kneading extruder at a temperature of 210 to 230 ° C. to produce a pellet for molding, followed by drying with hot air for injection molding. do.

As described above, the flame retardant thermoplastic resin composition obtained according to the present invention can be widely used in an area of high impact resistance, heat resistance, and flame retardancy, and particularly in flame retardancy due to improved dripping resistance during combustion, and particularly useful for housings of electrical and electronic products. Can be.

Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited by Examples.

Examples 1-4

Next, the composition and the content shown in Table 1 were extruded and kneaded at a temperature of 210 to 230 ° C., hot air dried at 120 ° C. for 4 hours, followed by injection molding at a temperature of 240 ° C., and then the impact strength was ASTM. D 256, tensile strength of ASTM D 638, heat deformation temperature of ASTM D 648 (applied to 18.6kg load), and workability and flowability according to ASTM D 1238, but melt flow by applying a load of 7.6kg at 2645 ℃. Evaluation was made by index.

Meanwhile, flame retardancy was measured and evaluated by the method according to UL 94, and the evaluation results are shown in Table 1 below.

Comparative Examples 1 to 7

Next, the composition and the content shown in Table 1 were melt-kneaded, injection molded, and evaluated in the same manner as in Example 1, and the physical properties were evaluated. The evaluation results are shown in Table 1 below.

TABLE 1

(1) Polycarbonate resins with average molecular weights of 30,000

(2) Acrylonitrile-butadiene-styrene graft copolymer resin.

(3) The bromine epoxy resin has an average molecular weight of about 80,000.

(4) A polyethylene wax having a molecular weight of 3,000 was used.

(5) di-stearyl-thio-di-propionate

(6) 4,4'-thio-bis (6-tert-butyl-3-methylphenol).

(7) Heat deflection temperature.

(8) Melt Flow Index.

(9) Flame retardant grade is evaluation of flame retardant grade according to UL standard, and excellent order is V-0, V-1, V-2, HB.

As can be seen from the above examples and comparative examples, the composition tool to be added in the present invention should be added in the range according to the present invention, it can be seen that the flame retardancy and heat resistance, etc. are balanced in a state in which all the physical properties are excellent.

Claims (2)

In a flame-retardant resin composition comprising a polycarbonate resin, an acrylonitrile-butadiene-styrene graft copolymer resin, and a bromine-based epoxy resin as a basic resin composition, 20 to 70% by weight of polycarbonate and atrylonitrile-butadiene-styrene graft 0.3 to 1 part by weight of Teflon 6 resin and 0.1 to 0.4% by weight of polyethylene resin based on 100 parts by weight of the base resin composition composed of 20 to 70% by weight of the copolymer resin and 10 to 20% by weight of the bromine epoxy resin of the following formula (I): 1.0 part by weight, 0.1 to 1.0 part by weight of di-stearyl-thio-di-propionate and 4,4'-thio-bis (6-pentyl-butyl-3-methylphenol) as antioxidants Flame retardant thermoplastic resin composition characterized in that it contains. Wherein n is an integer of 100 to 150. The flame retardant thermoplastic resin composition of claim 1, wherein the polycarbonate resin has a viscosity molecular weight of 18,000 to 30,000.