KR100425984B1 - flameproof thermoplastic polycarbonate resin composition with high impact strength - Google Patents

Abstract

The present invention contains (A) 45 to 95% by weight of a thermoplastic polycarbonate resin containing no halogen, (B) 5 to 50% by weight of a rubber modified styrene containing graft copolymer resin containing no halogen, and (C) a halogen. (D) 1 to 20 parts by weight of talc having an apparent specific gravity of 0.4 to 0.6 g / cc and a particle size of 2.0 to 3.0 탆, based on 100 parts by weight of a basic resin composed of 0 to 30% by weight of styrene-containing copolymer resin, It is related with the polycarbonate-type thermoplastic resin composition which has the flame resistance excellent in impact resistance characterized by consisting of 2-20 weight part of (E) phosphate ester compounds, and 0-2 weight part of (F) fluorinated polyolefin resin.

Description

Flameproof thermoplastic polycarbonate resin composition with high impact strength

Field of invention

The present invention relates to a polycarbonate-based thermoplastic resin composition having flame retardancy. More specifically, the present invention relates to a polycarbonate-based thermoplastic resin composition having flame resistance and excellent impact resistance. More specifically, the present invention is flame retardant excellent impact resistance made of polycarbonate resin, rubber modified styrene-containing graft copolymer, styrene-containing copolymer, talc, phosphate ester and fluorinated polyolefin resin having a specific size and high specific gravity It relates to a polycarbonate-based thermoplastic resin composition having.

Background of the Invention

Polycarbonate resins have excellent transparency, mechanical strength and heat resistance, and are used in many applications such as electric and electronic products and automobile parts. However, polycarbonate resins themselves have disadvantages of low notch impact strength and poor workability. Therefore, in order to improve workability and notch impact strength, it is blended with other kinds of resins. For example, the mixture of polycarbonate resin and styrene resin is a resin mixture which maintains high notch impact strength and improves workability. It is essential that the resin of this polycarbonate composition is flame retardant and maintains high mechanical strength because it is usually applied to large heat dissipating products such as computer housings or other office equipment. In particular, in recent years, as the thickness of the housing becomes thinner and the tendency to demand dimensional stability increases, an inorganic filler must be added to increase the flexural modulus and dimensional stability of the resin.

However, when glass fiber is added as an inorganic filler, the appearance of the molded product is deteriorated. In Japanese Patent Laid-Open No. 7-126510, the appearance of the molded product is improved by adding talc instead of glass fiber, but the impact of the resin due to talc The fall of strength was severe and it was difficult to use actually. On the other hand, Japanese Patent Application Laid-Open No. 8-176339 minimizes the decrease in impact strength by using talc having a high apparent specific gravity instead of the talc generally used.

Therefore, the present inventors have added a talc having a high apparent specific gravity and a specific particle size to the polycarbonate resin composition, thereby improving the impact resistance, minimizing the drop in impact strength, and improving the anti-dripping property. It was found that can be prepared.

An object of the present invention is to provide a polycarbonate-based thermoplastic resin composition which is excellent in impact resistance and minimizes the drop in impact strength.

Another object of the present invention is to provide a polycarbonate-based thermoplastic resin composition having excellent anti-dripping properties.

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

The polycarbonate-based thermoplastic resin composition of the present invention is (A) polycarbonate resin, (B) rubber modified styrene-containing graft copolymer, (C) styrene-containing copolymer, (D) apparent specific gravity is 0.4 to 0.6 g / cc It consists of a talc of particle size 2.0-3.0 micrometers, (E) phosphate ester, and (F) fluorinated polyolefin type resin, A detailed description of each of these components is as follows.

(A) polycarbonate resin

The polycarbonate resin (A) of the present invention is an aromatic polycarbonate which does not contain a halogen and is produced by the reaction of a divalent phenol compound with phosgene or diester carbonate. The structure of the divalent phenolic compound is represented by the following formula (I):

In the formula (Ⅰ) A is a single bond, C ₁ ~C ₅ alkylene, C ₂ ~C cycloalkylidene of ₅ alkylidene, C ₅ ~C ₆ a, S or SO _2.

Examples of the dihydric phenol compound represented by formula (I) include hydroquinone, resorcinol, 4,4'-dihydroxydiphenyl, 2,2'-bis (4-hydroxyphenyl) propane, and 1,1'- Bis (4-hydroxyphenyl) cyclohexane and the like. Bisphenols are preferable, and 2,2'-bis (4-hydroxyphenyl) propane, ie, bisphenol A is more preferable. Polycarbonate is prepared by reacting the divalent phenolic compound with phosgene on an interface or in a uniform phase. Polycarbonates of a specific molecular weight can be obtained by controlling the amount of chain terminators reacted with monophenols such as phenol, paracresol, paraisooctylphenol. The polycarbonate resin (A) of the present invention has a weight average molecular weight (M _w ) of 10,000 to 200,000, preferably 20,000 to 80,000. Meanwhile, the polycarbonate may be a homopolymer or a copolymer of a dihydric phenol compound.

The polycarbonate resin (A) together with the rubber modified styrene-containing graft copolymer (B) and / or the styrene-containing copolymer (C) constitutes a base resin. Polycarbonate is used in the range of 45 to 95% by weight in the total base resin.

(B) Rubber Modified Styrene-Containing Graft Copolymer

The rubber modified styrene-containing graft copolymer resin used in the present invention has a core shell structure in which a styrene monomer has a core structure and a vinyl cyanide monomer forms a shell in 5 to 95% by weight of the rubber modified polymer. It is a copolymer which grafted the mixture which has 95 to 5 weight%.

The rubber modified polymer is butadiene rubber, acrylic rubber, ethylene / propylene rubber, styrene / butadiene rubber, acrylonitrile / butadiene rubber, butadiene / styrene rubber, polyisoprene, ethylene-propylene-diene monomer terpolymer (EPDM), polio One or more rubbers selected from the group consisting of organosiloxanes and polyalkyl (meth) acrylate composite rubbers can be used.

As the styrene monomer, one or more monomers selected from the group consisting of styrene, α-methylstyrene, nuclear substituted styrene, and methyl methacrylate may be used.

In addition, as the vinyl cyanide monomer, one or more monomers selected from the group consisting of acrylonitrile, methacrylonitrile, methyl methacrylate, butyl acrylate, maleic anhydride and N-substituted maleimide may be used.

The graft copolymer resin may be prepared by a conventional polymerization method, but is preferably one synthesized by emulsion polymerization or bulk polymerization. Acrylonitrile / butadiene / styrene (ABS) resins in which acrylonitrile and styrene are grafted to butadiene rubber are widely used.

The rubber modified styrene-containing graft copolymer is used in the range of 5 to 50% by weight in the total base resin. The average size of the rubber particles in the preparation of the graft copolymer is in the range of 0.05 to 4㎛ considering the impact strength and appearance.

(C) styrene-containing copolymer

The styrenic-containing copolymer used in the present invention is 50 to 95% by weight of at least one of styrene, α-methylstyrene and nuclear substituted styrene, and acrylonitrile, methyl methacrylate, butyl acrylate, maleic hydride and At least one of the N-substituted maleimides consists of 5 to 50% by weight. As the styrene-containing copolymer resin, one produced by a conventional polymerization method can be used, and one synthesized by suspension polymerization or bulk polymerization is particularly suitable.

(D) Talc

In the present invention, talc is used as the inorganic filler. The talc used in the present invention preferably has an apparent specific gravity of 0.4 to 0.6 g / cc and a particle size of 2.0 to 3.0 mu.

(E) phosphate ester

Phosphate esters used in the present invention are represented by the following structural formula (II):

In the formula (II), Ar ¹ to Ar ⁴ are each independently a C _{6 to} C ₂₀ aryl group containing no halogen, or a C ₆ to C ₂₀ aryl group having 1 to 3 alkyl groups substituted, R Is arylene, and n is a number from 0 to 5. In the formula (II), when n is 0, it is a conventional monomolecular phosphorus flame retardant, and when n> 0, it is an oligomeric phosphorus flame retardant.

Phosphate esters used in the present invention are triphenylphosphate mixtures substituted with alkyl groups such as triphenylphosphate, t-butyl or isopropyl, resorcinol diphosphate, bisphenol-A oligomeric phosphate esters, tri (2,6-dimethyl Selected from mono- or oligomeric phosphate esters of phenyl) phosphate, tri (4-methylphenyl) phosphate, tricresylphosphate, diphenylcresylphosphate, triisopropylphenylphosphate, trigylenylphosphate, and xylenyldiphenylphosphate One or more mixtures.

(F) fluorinated polyolefin resin

Fluorinated polyolefin resins used in the present invention are conventionally available resins such as polytetrafluoroethylene, polyvinylidene fluoride, copolymers of tetrafluoroethylene and vinylidene fluoride, and tetrafluoroethylene and hexafluoro There is a copolymer of ropropylene. These may be used independently from each other, or a mixture of two or more different from each other may be used.

The fluorinated polyolefin resin which can be preferably used in the present invention is polytetrafluoroethylene. Polytetrafluoroethylene having a particle size of 0.05 to 1,000 mu is suitable for mixing. The usage-amount of fluorinated polyolefin resin is 0-2.0 weight part with respect to 100 weight part of base resins.

The fluorinated polyolefin resin prevents the dropping of the resin by decreasing the flow viscosity and increasing the shrinkage rate of the resin during combustion by forming a fibrous net in the resin during mixed extrusion. When the fluorinated polyolefin resin in an emulsion state is used, the dispersibility of the fluorinated polyolefin resin with respect to the entire resin is good, but there is a disadvantage in that the process is complicated.

The thermoplastic resin composition of the present invention is mixed in a conventional mixer after adding an inorganic additive, a heat stabilizer, an antioxidant, a light stabilizer, a pigment and / or a dye according to each use. This mixture is prepared into a resin composition in pellet form through an extruder.

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

(A) polycarbonate resin, (B) rubber modified styrene-containing graft copolymer, (C) styrene-containing graft copolymer, (D) talc used in Examples 1 to 3 and Comparative Examples 1 to 5 below The specification of (E) phosphate ester and (F) fluorinated polyolefin resin is as follows.

(A) polycarbonate resin

A bisphenol A polycarbonate having a weight average molecular weight (M _w ) of the polycarbonate resin is 10,000 to 200,000, preferably 20,000 to 80,000.

(B) Rubber modified styrene-containing graft copolymer (g-ABS)

Butadiene rubber latex was added so that the content of butadiene was 45 parts by weight with respect to the entire monomer, 1.0 parts by weight of potassium oleate, 1.0 part by weight of urea peroxide, and 0.4 parts by weight of cuene hydroperoxide By weight, 0.3 parts by weight of mercaptan-based chain transfer agent was added to maintain the reaction at 75 ℃ for 5 hours to prepare a g-ABS latex. The resulting polymer latex was added to 1% sulfuric acid solution and dried after coagulation to prepare a graft copolymer resin in powder form.

(C) Styrene-containing copolymer resin (SAN)

A SAN copolymer resin was prepared by suspension polymerization by adding 0.2 parts by weight of azobisisobutyronitrile and 0.5 parts by weight of tricalcium phosphate, which are necessary additives to a mixture of 70 parts by weight of styrene, 30 parts by weight of acrylonitrile, and 120 parts by weight of deionized water. . The copolymer was washed with water, dehydrated and dried to obtain a SAN copolymer resin in powder form.

(D) talc

Talc having an apparent specific gravity of 0.5 g / cc and an average particle size of 2.5 mu was used.

(E) phosphate ester

Commercially available resorcinol diphosphate (RDP) was used.

(F) fluorinated polyolefin resin

Polytetrafluoroethylene having an average particle size of 10 to 50 µm was used.

The composition and measured physical properties of each component used in Examples 1 to 3 and Comparative Examples 1 to 5 are shown in Table 1. Examples 1 to 3 are inorganic fillers with an apparent specific gravity of 0.5 g / cc and an average particle size. It is the resin composition which mixed and used the talc which is 2.0-3.0 micrometers. Comparative Examples 1-5 are resin compositions using a mixture of talc, clay and calcium carbonate (CaCO ₃ ).

As shown in Table 1, each component was mixed and the antioxidant and heat stabilizer were added, mixed in a conventional mixer, and then introduced into a twin screw extruder having a L / D of 29 and ￠ = 45 mm. The mixture was prepared into a resin composition in pellet form through an extruder, and a specimen was prepared at an injection temperature of 250 ° C., and then left at 23 ° C. and a relative humidity of 50% for 40 hours to measure physical properties.

TABLE 1

Property measurement

(1) Flame retardancy: measured according to the UL94 method.

(2) Impact strength: measured by ASTM method.

As shown in Table 1, Examples 1 to 3 according to the present invention have impact strength and flame retardancy compared to Comparative Examples 1 to 5 by using talc having an apparent specific gravity of 0.5 g / cc and an average particle size of 2.0 to 3.0 μ. This much superior resin composition could be manufactured.

The present invention has excellent impact resistance and minimizes the impact strength by using talc having an apparent specific gravity of 0.4 to 0.6 g / cc and a particle size of 2.0 to 3.0 μ as an inorganic filler, and has an anti-drip property. It has the effect of providing the polycarbonate-based thermoplastic resin composition having excellent flame retardancy.

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)

45 to 95% by weight of (A) halogen-free thermoplastic polycarbonate resin, (B) 5 to 50% by weight of rubber-modified styrene-containing graft copolymer resin containing no halogen, and (C) free of halogen 100 parts by weight of a base resin composed of 0 to 30% by weight of a styrene-containing copolymer resin; (D) 1 to 20 parts by weight of talc having an apparent specific gravity of 0.4 to 0.6 g / c.c and a particle size of 2.0 to 3.0 mu; (E) 2-20 weight part of phosphate ester; And 0 to 2 parts by weight of (F) fluorinated polyolefin resin; Polycarbonate-based thermoplastic resin composition having a flame resistance excellent in impact resistance. The polycarbonate-based thermoplastic resin composition of claim 1, wherein the phosphate ester compound is represented by the following structural formula (II): In formula (II), Ar ¹ to Ar ⁴ are one or more mixtures of cresyl, phenyl, xylene, propylphenyl, butylphenyl, and bromine or chlorine substituent, R is arylene, and n is 0 Number from 5 to 5. The method of claim 1, wherein the fluorinated polyolefin resin (F) is polytetrafluoroethylene, polyvinylidene fluoride, a copolymer of tetrafluoroethylene and hexafluoropropylene, and tetrafluoroethylene and hexafluoropropylene. Polycarbonate-based thermoplastic resin composition having a flame retardancy excellent in impact resistance, it is selected from the group consisting of a copolymer of. The polycarbonate-based thermoplastic resin composition of claim 1, wherein the resin composition further comprises an inorganic additive, a heat stabilizer, an antioxidant, a light stabilizer, a pigment, and / or a dye.