JPH10237291A - Flame retardant thermoplastic resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a flame retardant thermoplastic resin composition which does not suffer a juicing phenomenon, has good processability and is free from a deviation in physical properties during processing by using as the constituents a base resin consisting of a thermoplastic polycarbonate and an ABS resin having a core-shell structure, a phosphate composition, a perfluoroalkane polymer and additives. SOLUTION: A base resin consisting of 80-96wt.% aromatic polycarbonate resin and 4-20wt.% core-shell ABS resin with a graft ratio of at least 40%, obtained by grafting 25-45wt.% styrene and 10-15wt.% acrylonitrile onto 45-60wt.% butadiene rubber, in an amount of 100 pts.wt. is mixed with 5-20 pts.wt. phosphate composition of the formula (wherein R1 to R5 are each a non-halogenated 6-20C aryl, or an alkyl-substituted 6-20C aryl; and (n) is 0 to 5, with the average (n) being 0.3 to 0.8) and 0.1-2.0 pts.wt. perfluoroalkane polymer. This mixture is then mixed with additives comprising, e.g. an organic filler and a heat stabilizer in a mixer.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a thermoplastic resin composition having flame retardancy. More specifically, the present invention is a halogen-free thermoplastic polycarbonate resin and ABS (acrylo) having a core-shell structure.
The present invention relates to a flame-retardant thermoplastic resin composition composed of a base resin composed of a base resin, a phosphate composition, and a perfluoroalkane polymer.

[0002] In the thermoplastic resin composition of the present invention, an inorganic additive, a heat stabilizer, an antioxidant, a dye, and / or a pigment are added in necessary amounts depending on the intended use of the resin composition.

[0003]

2. Description of the Related Art Polycarbonate resin moldings are excellent in transparency, impact resistance and heat resistance, and are widely used for electric and electronic products and automobile parts. However, since the polycarbonate resin molded body has poor workability, it is used by being mixed with other resins. For example, a mixture of a polycarbonate resin and a styrene-based resin is a resin mixture having high notch impact strength and improved workability.

Further, another essential requirement for a polycarbonate resin composition used in household articles and computer housing materials is that the resin must have flame retardancy.

Many studies have been made on techniques for imparting flame retardancy to resin compositions. Among them, a method for imparting flame retardancy to resin compositions by melt-mixing a halogen compound and an antimony compound with a polycarbonate resin is disclosed. Is used.

In US Pat. Nos. 4,983,658 and 4,883,835, a halogen compound and a phosphate ester compound are used as a flame retardant in a polycarbonate resin, and a flow of polytetrafluoroethylene is grafted to ABS. It discloses a resin composition mixed with a resin to give flame retardancy. However, although these halogen compounds can fully exhibit the flame-retardant function in the event of a fire, decomposition gases are generated during processing of the resin, causing not only corrosion in the mold, but also bromination, which is a bromo compound. When diphonyl ether is used, there is a high possibility that toxic gas such as dioxin or difuran, which is harmful to humans, is generated.

In US Pat. No. 4,692,488, halogen-free polycarbonates, halogen-free copolymers of styrene and (meth) acrylonitrile, halogen-free phosphorus compounds, tetrafluoroethylene polymers, AB
Disclosed are compositions made from S-graft polymers.

In the US patent, the phosphorus compound and the perfluoroaurcan polymer for imparting flame retardancy to the polycarbonate / ABS resin composition play a role in preventing dripping during burning.

Although this resin composition has sufficient flame retardancy, a juicing phenomenon in which a crack occurs on the surface during molding occurs, thereby deteriorating the physical properties of the resin composition.

US Pat. No. 5,204,394 discloses the use of a phosphate oligomer or a mixture of phosphate oligomers as a flame retardant in aromatic polycarbonates, styrene-containing copolymers and / or styrene-containing graft copolymers to prevent the phenomenon of juicing. A resin composition is disclosed. The phosphorus compounds used in the aforementioned U.S. patents include triaryl phosphates and phosphate oligomers. When a triaryl phosphate is used for a polycarbonate resin, a large amount of stress is applied during processing, and therefore, there is a high possibility that a vaporized flame retardant forms a layer and causes a juicing phenomenon. In addition, the use of triaryl phosphate has a problem of lowering the heat resistance of the polycarbonate resin. When a phosphate oligomer is used for a polycarbonate resin, no juicing phenomenon occurs, but the appearance of a molded article is not good. In addition, when the same content is used as compared with the case of using a triaryl phosphate, there is a disadvantage that the flame retardancy is reduced.

In the above-mentioned US patent, a polycarbonate resin and a SAN (styrene / acrylonitrile) copolymer resin are used as the base resin, and g-ABS (graft-acrylonitrile /
butadiene / styrene) resin is used.
However, these base resins have been found to cause a phenomenon in which the grafted rubber particles are aggregated in a SAN phase depending on the processing conditions. That is, depending on the resin processing conditions
g-ABS resin is not grafted with better common affinity
It is highly likely that the resin is mainly agglomerated by the SAN resin, and the SAN resin does not have the usual utility with the polycarbonate resin, so that phase separation occurs during processing. Therefore, a phenomenon occurs in which the grafted rubber particles are not uniformly distributed over the entire resin, and are concentrated on the SAN resin having better affinity. The phenomenon in which the grafted rubber particles gather in the SAN phase causes severe deviation in the physical properties of the resin. In particular, such a phenomenon is considered to be caused by a difference in affinity between the mixed resins in response to the heat history due to the injection when a polycarbonate-based resin composition that has been sufficiently kneaded during extrusion is injected. .

In order to solve the above-mentioned problems, the present inventors have disclosed in Korean Patent Application No. 95-4542 (US Patent Application No. 08 / 449,521) a thermoplastic polycarbonate resin and a styrene-containing graft. A thermoplastic resin composition comprising a phosphate composition and a perfluoroalkane polymer as a base resin comprising a polymer resin is disclosed.

The resin composition of the above-mentioned patent application No. 95-4542 is prepared by juicing by deforming a styrene-containing graft copolymer resin constituting a base resin.
The present invention relates to a flame-retardant resin composition which does not cause phenomena, does not cause a deviation in physical properties depending on processing conditions, and has excellent workability and weld line strength.

[0014] Continuing with the above-mentioned patent application No. 95-4542, the present inventors have grafted methyl methacrylate, butyl acrylate and styrene onto butadiene rubber instead of the styrene-containing graft copolymer resin. By applying a phosphate composition and a perfluoroalkane polymer using the copolymerized resin, the grafted rubber particles are not aggregated, and a resin composition in which the rubber particles are uniformly distributed is disclosed in Korean Patent Application No. 95-. Filed 24618.

The resin composition of the present invention having the same purpose as the above-mentioned patent application is grafted by using an ABS resin having a core-shell structure in place of the above graft copolymer resin. Rubber particles are not agglomerated,
It was found that the impact strength was good.

[0016]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a polycarbonate having a core-shell structure.
By using a phosphate composition and a perfluoroalkane polymer as the base resin consisting of ABS resin, it has good workability without juicing phenomenon and has flame retardancy with no physical property deviation during the processing process It is to provide a thermoplastic resin composition.

Another object of the present invention is to use a phosphate composition and a perfluoroalkane polymer as a base resin comprising a polycarbonate and an ABS resin having a core-shell structure so that resin particles are uniformly distributed. An object of the present invention is to provide a flame-retardant thermoplastic resin composition.

Still another object of the present invention is to provide a flame-retardant thermoplastic resin composition having excellent impact strength irrespective of the thickness of a molded article.

[0019]

The thermoplastic resin composition of the present invention comprises (A) (1) 80 to 96% by weight of a halogen-free thermoplastic polycarbonate resin; and (2) butadiene rubber 45.
60% by weight to 45% to 25% by weight of styrene and acrylonitrile
ABS resin having a core-shell structure and a graft ratio of 40% or more
(B) 5 to 20 parts by weight of a phosphate composition having the structure of the following formula and (C) 0.1 to 2.0 parts by weight of a perfluoroalkane polymer. Are mixed.

[0020]

Embedded image

The flame-retardant thermoplastic resin composition of the present invention has (A) polycarbonate and a core-shell structure.
A base resin comprising an ABS resin, (B) a phosphate composition, and (C) a perfluoroalkane polymer.
The explanation for each of these components is as follows.

(A) Base Resin The base resin is a blend of polycarbonate and an ABS resin having a core-shell structure. More specifically, the base resin is a polycarbonate resin 80-96% by weight
And 4 to 20% by weight of an ABS resin having a core-shell structure.
Consists of

The polycarbonate resin includes an aromatic polycarbonate, an aliphatic polycarbonate and an aromatic / aliphatic polycarbonate, depending on the type of the substituent, and these are used alone or in a mixture (bland). Aromatic polycarbonate is preferred, among which,
Further preferred is a polycarbonate whose structural unit is bisphenol A (2,2'-bis (4-hydroxyphenyl A) propane).

The styrene-containing graft copolymer has a hemisphere structure due to the structure of its graft shell.
phere) structure and core-shell structure.

The present invention was studied with respect to ABS, which is a typical example of a styrene-containing graft polymer. As a result of experiments on ABS resins having a hemisphere structure and a core-shell structure, the core-shell structure was determined. When using ABS resin as a part of the base resin, they came to discover that rubber particles were distributed uniformly, had excellent impact strength, and were also excellent in other physical properties such as juicing phenomenon and flame retardancy. .

In the styrene-containing graft polymer,
The preparation of a graft copolymer having a hemisphere structure and a core-shell structure can be easily performed by those having ordinary skill in the art. Having a core-shell structure
ABS resin is manufactured by the usual polymerization method.
Emulsion polymerization is one of the methods most applicable to the present invention.

The ABS resin having a core-shell structure used by being mixed with the above polycarbonate resin is obtained by graft polymerization of 45 to 60% by weight of butadiene rubber, 25 to 45% by weight of styrene, and 10 to 15% by weight of acrylonitrile. ,
Preferably, the graft ratio is 40% or more, and the content of the gel that is not dissolved when dissolved in acetone is 70% by weight or more. In particular, the base resin of the resin composition of the present invention has a separately polymerized SAN to prevent the aggregation phenomenon of particles.
It is characterized in that no copolymer resin is added.

The polycarbonate resin is used in an amount of 80 to 96% by weight based on the total weight of the base resin of the present invention.
ABS resin with a shell structure is used for the entire base resin.
Use with 4-20% by weight. 80 weight of polycarbonate resin
% Or less, the flame retardancy is reduced, and if it is 96% by weight or more, the styrene-containing graft copolymer resin does not exhibit sufficient impact reinforcing effect on the polycarbonate resin.

(B) Phosphate composition The phosphate composition used in the present invention has the structure of the following formula:

[0030]

Embedded image

The average value of n of the phosphate composition of formula 1 used in the present invention is in the range of 0.3 to 0.8. That is, the phosphate composition typically has n between 0 and 5
The compounds which are present in the form of a mixture having values up to and which have an average value of from 0.3 to 0.8 are used in the present invention. When n is 0 in the above general formula (I), the phosphate composition is a monomolecular triaryl phosphate, and when n is 1, 2, 3, 4, or 5, it is an oligomeric triaryl phosphate.

Examples of the monomolecular triaryl phosphate include triphenyl phosphate, tri (2,6-dimethylphenyl) phosphate, tri (4-methylphenyl)
Phosphate, tricresyl phosphate, diphenyl
2-ethyl cresyl phosphate, diphenyl cresyl phosphate, tri (isopropylphenyl) phosphate, trigylenyl phosphate, gylenyl phenyl phosphate and the like. When n is 0, the monomolecular form of the triaryl phosphate is 200
Since it has a property of being easily volatilized at a high temperature of not less than ° C., it has a disadvantage that a flame retardant volatilized during a processing process such as injection is laminated and a juicing phenomenon occurs. When the average value of n of the oligomer is 1.2 or more, the juicing phenomenon is remarkably reduced, but the flame retardancy is reduced, which adversely affects the uniform distribution of the rubber particles grafted in the resin. As a result, mechanical properties, particularly impact strength, are reduced. Therefore, the use of a phosphate in which the average value of n in the above general formula (I) is 0.3 to 0.8 improves not only the flame retardant but also the physical properties. Phosphate compositions having an average value of n of from 0.3 to 0.8 comprise 30 to 60% by weight of monomolecular triaryl phosphate and 40 to 70% by weight of oligomeric triaryl phosphate. Also,
Synthetic triaryl phosphate oligomers having an average value of n of 0.3 to 0.8 are also used in the present invention.

The triaryl phosphate oligomer is produced by heating a solution obtained by adding phenol, resorcinol and dichloromagnesium to benzene, and then dropping trichlorophosphine oxide into the solution. The phosphate composition is 100% by weight of the base resin of the present invention.
It is preferably used in the range of 5 to 20 parts by weight with respect to

(C) Perfluoroalkane polymer The perfluoroalkane polymer may be a conventionally available resin such as polytetrafluoroethylene, polyvinylidene fluoride, a copolymer of tetrafluoroethylene vinylidene fluoride, tetrafluoroethylene and fluoroalkyl. There are copolymers of vinyl ether and copolymers of tetrafluoroethylene and hexafluoropropylene. These are used independently of each other, or a mixture of two or more different phases is used. The perfluoroalkane polymer is mixed with the resin and extruded to prevent dripping during combustion.
etwork) to reduce the flow viscosity of the resin during combustion, increase the shrinkage and prevent dripping of the resin. In order to uniformly disperse and mix in the flame-retardant resin composition, it is preferable to use a powdery perfluoroalkane polymer. The perfluoroalkane polymer preferably used in the present invention is polytetrafluoroethylene. Polytetrafluoroethylene having a particle size of 20-500 μ is suitable for mixing. The amount of the perfluoroalkane polymer used is 0.1 to 2.0 parts by weight based on 100 parts by weight of the base resin. The thermoplastic resin composition of the present invention is obtained by mixing a phosphate composition and a perfluoroalkane polymer with a base resin composed of a polycarbonate resin and an ABS resin having a core-shell structure, and adding an inorganic additive necessary for the mixture and heat stability. Agents, antioxidants, light stabilizers, pigments, and / or
Alternatively, a dye is added, and the mixture is mixed with an ordinary mixer to produce.
The mixture is again passed through an extruder to produce a resin composition in a pellet state. The thermoplastic resin composition of the present invention may contain an inorganic additive, a heat stabilizer, an antioxidant, a light stabilizer, a pigment, and / or a dye depending on the intended use. As inorganic additives to be added, there are asbestos, glass fiber, talc and ceramics, which are used in the range of 0 to 30 parts by weight based on 100 parts by weight of the base resin. The thermoplastic resin composition of the present invention can prevent the generation of toxic gas, which is a problem when a conventional halogen compound is used as a flame retardant, and a problem when only a conventional triaryl phosphate is used as a flame retardant. The problem of poor surface condition such as the juicing phenomenon and the decrease in heat resistance can be prevented, and the processability which is a problem when only an aryl phosphate oligomer excluding the conventional triaryl phosphate is used as a flame retardant is prevented. The resin composition is capable of remarkably refining the problem of surface discoloration during processing due to the reduction, and as shown in a transmission electron microscope photograph, the grafted rubber particles are uniformly distributed throughout the resin to provide uniform physical properties.

The present invention can be better understood with reference to the following examples, which are for illustrative purposes of the present invention and which are intended to limit the scope of protection limited by the appended claims. is not.

[0036]

EXAMPLES The preparation and specifications of each component used in Examples 1-2 and Comparative Examples 1-6 below are as follows.

(A) Basic resin (a ₁ ) Polycarbonate resin: L-1225L manufactured by TEIJIN of Japan
Grade was used.

(A ₂ ) ABS resin having a core-shell structure A butadiene rubber latex is charged so that the butadiene content is 50% by weight based on the whole monomer, and 12 parts by weight of styrene, 4 parts by weight of acrylonitrile and Deionized water
Mix 150 parts by weight, and use as an additive Rojon soap (Ros
in Soap) 1 part by weight, tetrasodium pyrophosphate 0.
2 parts by weight, 0.4 parts by weight of glucose, 0.006 parts by weight of iron sulfate, 0.25 parts by weight of cumene hydroperoxide and 0.2 parts by weight of a mercaptan-based chain transfer agent were mixed, and the internal temperature of the reactor was raised to 75 ° C. After maintaining at that temperature for 1 hour, a mixture of 26 parts by weight of styrene, 8 parts by weight of acrylonitrile, 0.25 parts by weight of peroxide, and 0.2 parts by weight of mercaptan-based chain transfer agent was added dropwise for 3 hours to react. Was terminated. The ABS resin thus produced had a core-shell structure, and a 1% sulfuric acid solution was added to the polymer latex, and the mixture was coagulated and dried to produce a powder.

[0039] (a ₃₎ 50 parts by weight of butadiene rubber latex ABS resin solids having a HemisFair structure, styrene
36 parts by weight, acrylonitrile 14 parts by weight, and deionized water
To 150 parts by weight of the mixture, 1.0 parts by weight of potassium oleate, 0.4 parts by weight of cumene hydroperoxide, and 0.3 parts by weight of a mercaptan-based chain transfer agent, which are necessary additives, were added.
The reaction was completed by maintaining the temperature at 75 ° C. for 5 hours.
Latex was produced. To the resulting resin composition, 0.3 parts by weight of sulfuric acid was added and coagulated to produce an ABS resin having a hemisphere structure in a powder state.

[0040] (a ₄₎ SAN copolymer resin of styrene 70 parts by weight of acrylonitrile 30 parts by weight, and azobisisobutyronitrile is necessary additives to the mixture of deionized water 120 parts by weight (azobisisobutylonitrile) 0.2
Parts by weight and 0.5 parts by weight of tricalcium phosphate were added thereto and subjected to suspension polymerization to produce a SAN copolymer resin. The copolymer was washed with water, dehydrated and dried to obtain a powdery SAN copolymer resin.

(B) Phosphate composition Triphenyl phosphate (n = 0): Triphenyl phosphate (TPP) manufactured by Daihachi Japan was used.

Aryl phosphate oligomer (n = 1.
4): CR-733S from Japan (Daihachi) was used.

The synthesized aryl phosphate oligomer (n = 0.6): 114.7 g of phenol, 220 of resorcinol
g and 0.2 g of dichloromagnesium in 100 ml of benzene
After heating to 70 ° C., 82.8 g of trichlorophosphine oxide was added dropwise at this temperature over 2 hours.

After completion of the reaction, at a temperature of 120 ° C. for 3 hours,
Stir to keep until no more hydrogen chloride gas is generated, remove solvent and impurities and remain in liquid state at actual temperature,
The freezing point is −10 ° C. or less, and the value of n is 0.1 in the above chemical formula 1.
An arylphosphate oligomer was prepared.

(C) Perfluoroalkane polymer Teflon 7AJ manufactured by Dupont of the United States was used.

(Examples 1-2 and Comparative Examples 1-6)
Composition of each component used in 1-2 and Comparative Examples 1-6 is shown in the table.
1 In Examples 1-2, no ABS or SAN copolymer having a hemisphere structure was used.In Comparative Examples 1-2, only an ABS having a hemisphere structure was used.In Comparative Examples 3-6, a hemisphere structure was used. ABS and SAN copolymers were used.

The above Examples 1 and 2 and Comparative Examples 1 to 6
Then, the respective components were mixed to produce a resin composition in an extruded pellet state. Each of the resin compositions in the form of pellets was injected at the injection temperatures shown in Table 1 to produce test pieces.

[0048]

[Table 1]

The above Examples 1 and 2 and Comparative Examples 1 to
The flame retardancy, heat resistance and impact strength of the test piece of the resin composition prepared in 6 were measured, and the juicing phenomenon and the aggregation of the grafted rubber particles were observed. Whether the grafted rubber particles are agglomerated is determined according to Examples 1 to
TEM (Transmissi
on Electron Microscope). This TE
The M photo is a 5,000 magnification photo. TEM photographs of the coupons according to Examples 1-2 show that the grafted rubber particles are uniformly distributed without agglomeration. However, TEM photographs of the coupons according to Comparative Examples 1-4 show that the grafted rubber particles are not always uniformly distributed depending on the injection temperature conditions. In Comparative Examples 3 and 4, a phenomenon occurs in which the grafted rubber particles are aggregated in the SAN phase. By the way, Comparative Example 1
Shows a uniform distribution without agglomeration of the grafted rubber particles. Comparative Example 2 shows how much the rubber particles are aggregated. This is presumed to be different depending on the temperature at which the resin composition is injected. Although TEM photographs for Comparative Examples 5 and 6 were not attached, Comparative Example 1
And similar results to 2. That is, the aggregation phenomenon did not appear in Comparative Example 5, but the aggregation phenomenon appeared in Comparative Example 6 depending on the injection operation conditions and the sample thickness. For example, in Comparative Example 6, when the thickness of the molded product was 1/4 ", the aggregation phenomenon occurred, but when it was 1/8", the aggregation phenomenon did not occur. The results are shown in Table 2.

[0050]

[Table 2]

[Brief description of the drawings]

FIG. 1 is a transmission electron microscope (TEM) of a resin composition according to Example 1 of the present invention.
ope).

FIG. 2 is a transmission electron micrograph of a resin composition according to Example 2 of the present invention.

FIG. 3 is a transmission electron micrograph of a resin composition according to Comparative Example 1 of the present invention.

FIG. 4 is a transmission electron micrograph of a resin composition according to Comparative Example 2 of the present invention.

FIG. 5 is a transmission electron micrograph of a resin composition according to Comparative Example 3 of the present invention.

FIG. 6 is a transmission electron micrograph of a resin composition according to Comparative Example 4 of the present invention.

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[Procedure amendment]

[Submission date] April 18, 1997

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Claims

[Correction method] Change

[Correction contents]

[Claims]

Embedded image (C) relative to said base resin 100 parts by weight, perfluoroalkane polymer from 0.1 to 2.0 parts by weight; the thermoplastic resin composition having flame retardant, wherein the composed this <br/> from .

Embedded image (C) 0.1 to 2.0 parts by weight based on 100 parts by weight of the base resin.
Parts perfluoroalkane polymer; (D) inorganic additives, heat stabilizers, antioxidants, light stabilizers,
Selected from the group made from pigments and mixtures thereof
Additive, which has flame retardancy
Thermoplastic resin composition.

Continuing on the front page (72) Inventor Jan Sam Ju Tayhammingok Kungki de Soo Wong Jangan Kuh Jungja Dong (No Address) Dongsin Apartment 109-70・ Do Kuompo Qemjung Dong 743-7

Claims (1)

[Claims] 1. (A) (1) 80 to 96% by weight of halogen-free thermoplastic polycarbonate resin; and (2) 45 to 60% by weight of butadiene rubber, 45 to 25% by weight of styrene and 10 to 15% by weight of acrylonitrile. (B) the base resin having a core-shell structure and having a graft ratio of 40% or more and having a core-shell structure having a core-shell structure of 4 to 20% by weight; 5 to 20 parts by weight of 30 to 60% by weight of a monomolecular triaryl phosphate and 70 to 40% by weight of an oligomeric triaryl phosphate based on 100 parts by weight of the base resin A phosphate composition; (C) 0.1 to 2.0 parts by weight of a perfluoroalkane polymer based on 100 parts by weight of the base resin; (D) an inorganic additive, a heat stabilizer, an antioxidant, a light stabilizer,
An additive selected from the group consisting of pigments and mixtures thereof; a thermoplastic resin composition having flame retardancy.