JP2001098141A - Flame-retardant thermoplastic resin composition and extruded plate of flame-retardant thermoplastic resin - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a flame-retardant thermoplastic resin composition capable of providing an extruded plate having excellent fabrication quality such as vacuum molding, pressure forming, etc., excellent balance of physical properties of flame retardance, impact strength, heat distortion temperature, etc. SOLUTION: This flame-retardant thermoplastic resin composition is obtained by compounding a resin composition composed of 30-70 pts.wt. of an ABS-based resin and 70-30 pts.wt. of a percarbonate-based resin (the total of both the resins is 100 pts.wt.) with 1.0-10.0 pts.wt. of a composition composed of an acrylic copolymer having a higher molecular weight than those of the ABS-resin resin and the percarbonate-based resin, <=18 pts.wt. of a bromine-based flame retardant having >=60% bromine content and 180 deg.C to 240 deg.C melting point, antimony trioxide as a flame-retardant auxiliary in an amount of 1/5 to 1/3 the amount of the bromine-based flame retardant. The composition composed of the acrylic copolymer has a linear structure and 1,000,000 to 5,000,000 weight- average molecular weight.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flame-retardant thermoplastic resin composition and a flame-retardant thermoplastic resin extruded plate which can be used for a plate material subjected to secondary processing involving heating such as vacuum forming and pressure forming. More specifically, the present invention relates to an improvement in an alloy (hereinafter, abbreviated as PC / ABS alloy) composition of an ABS resin and a polycarbonate (PC) resin, and more specifically, it is excellent in impact resistance and flame retardancy. The present invention relates to a flame-retardant thermoplastic resin composition for an extruded plate and a flame-retarded thermoplastic resin extruded plate having good vacuum moldability.

[0002]

2. Description of the Related Art A sheet obtained by extruding an ABS resin has excellent characteristics such as impact resistance, water resistance, oil resistance, chemical resistance, dimensional stability and appearance quality. It has the feature that the physical properties of the resin can be adjusted over a wide range by changing the composition. However, depending on the application, the heat resistance and the impact resistance are basically inferior, so that the use may be restricted.

Further, in order to impart sufficient flame retardancy to a plate made of ABS resin, it is necessary to add a large amount of a flame retardant, in which case the physical properties are significantly reduced and even if flame retardancy can be secured. In addition, problems such as a decrease in impact strength and heat deformation temperature occur, and it is difficult to achieve both of these properties. further,
Vacuum forming has drawbacks such as draw-down, that is, bending of the central portion of the plate due to heating by a heater is large, and forming is difficult, and since the moisture absorption rate is high, appearance defects are likely to occur due to foaming.

On the other hand, a plate formed by extruding a PC resin is
It has excellent characteristics such as heat resistance, impact resistance, transparency, and dimensional stability. The oxygen index of the resin itself is higher than that of the ABS resin. Although it is easier than this, there is a problem that the chemical resistance is inferior and the impact strength has a large thickness dependency. Furthermore, there is a problem that the tensile elongation at break in the vacuum forming temperature range is basically insufficient, and deep forming (deep drawing) cannot be performed.

[0005] In order to make use of the advantages of the two types of resins and to compensate for the disadvantages, polymer alloy materials comprising both have been put to practical use, and those obtained by adding a flame retardant to the alloy materials have already been widely used in injection molding applications and the like. Have been.

Hitherto, as a bromine-based flame retardant generally added to a PC resin or an ABS resin, a high melting point flame retardant such as decabromodiphenyl ether has been used, but a PC / ABS alloy composition has been used. Since it does not melt at the extrusion molding temperature, the particles are dispersed in the base resin, and there have been problems such as a reduction in impact strength and a break start point during vacuum molding.

Accordingly, a molecular weight of 1,000 to 4, having a form in which a plurality of 4-brominated bisphenol A structures, 4-brominated bisphenol A / diglycidyl ether structures, and the like are polymerized.
So-called oligomer type flame retardants of about 30,000 have been developed. This form of flame retardant can be used to adjust the melting point by adjusting the number of polymerizations of the basic structure, and it can be expected to improve the flowability of PC resin in injection molding of PC resin, etc. It is becoming.

[0008]

However, an extruded plate formed of a composition obtained by simply alloying an ABS resin and a PC resin does not provide good vacuum moldability and air pressure moldability. No good extruded plate could be used.

In addition, the brominated oligomer type flame retardant can be melted at the extrusion molding temperature of the PC / ABS resin by adjusting the melting point, and can be dispersed not in particles but in molecules. But PC / AB
With respect to the extruded plate of the S-based resin, it was not always possible to obtain a satisfactory impact strength.

That is, the melting point of the brominated oligomer type flame retardant is slightly lower than the extrusion molding temperature of the PC / ABS resin.
To set the temperature to about 0 ° C. to 240 ° C., it is necessary to set a high molecular weight. However, when the molecular weight is increased in the structure, the linear structure of the molecule becomes remarkable, and in the base resin during extrusion molding, Since the molecular orientation occurs, a remarkable difference in impact strength between the flow direction (MD direction) and the direction perpendicular to the direction (TD direction) at the time of extrusion molding occurs.

Further, since these brominated oligomer type flame retardants have a low bromine content, they need to be added in a larger amount than when other types of brominated flame retardants are used, and this also makes physical properties more evident. Acts in the direction.

The present invention has been made in view of the above problems, and a first object of the present invention is to provide excellent secondary workability such as vacuum forming and pressure forming, flame retardancy, impact strength, and heat deformation temperature. It is an object of the present invention to provide a flame-retardant thermoplastic resin composition which can obtain an extruded plate excellent in balance of various physical properties such as the above. A second object is to provide a flame-retardant thermoplastic resin extruded plate obtained by extruding the composition.

[0013]

According to the first aspect of the present invention, an ABS resin 30 is provided.
An acrylic copolymer having a molecular weight higher than that of the ABS resin and the polycarbonate resin is added to a resin composition containing 70 to 30 parts by weight of the polycarbonate resin and 70 to 30 parts by weight of the polycarbonate resin (the total of both is 100 parts by weight). 1.0 to 10.0 parts by weight of a composition comprising: and 18 parts by weight or less of a bromine-based flame retardant having a bromine content of 60% or more and a melting point in the range of 180 ° C. to 240 ° C. A combustion aid was added.

According to a second aspect of the present invention, in the first aspect of the present invention, antimony trioxide is used as the flame retardant auxiliary, and the amount of the antimony trioxide is 1/5 or more of the amount of the brominated flame retardant. is there.

According to a third aspect of the present invention, in the first or second aspect of the invention, the composition comprising the acrylic copolymer is a copolymer of a methacrylic ester and an acrylic ester, Alternatively, a copolymer of methacrylic esters of different types is used as a basic component, has a linear structure, and has a weight average molecular weight in the range of 1,000,000 to 5,000,000.

According to a fourth aspect of the present invention, there is provided the flame-retardant thermoplastic resin composition according to any one of the first to third aspects, wherein the flame-retardant thermoplastic resin composition is extruded by an extruder. It was extruded into a plate shape.

Therefore, in the extruded plate molded from the resin composition of the first aspect of the present invention, the presence of the composition composed of an acrylic copolymer having a higher molecular weight than that of the ABS resin and the polycarbonate resin. In the heating temperature range at the time of secondary processing such as vacuum forming and pressure forming, even if the temperature is uneven, the fluidity does not change excessively even if the temperature is uneven, and the thickness is not uniform at the time of forming, or molding is impossible due to breakage. Is suppressed. In addition, molding failure due to an increase in drawdown and insufficient breaking elongation during molding is prevented. Further, the bromine content is 60% or more and the melting point is 180 ° C to 2 ° C.
Since the bromine-based flame retardant in the range of 40 ° C. and the flame retardant aid are added in an amount of 18 parts by weight or less, the flame retardancy is ensured in a state in which a decrease in physical properties is suppressed.

According to a second aspect of the present invention, in the first aspect of the present invention, antimony trioxide is used as the flame retardant auxiliary, and the amount of the antimony trioxide is 1/5 or more of the amount of the brominated flame retardant. For this reason, the use of readily available flame-retardant auxiliaries achieves a flame-retardant level above the UL standard of 94V-2 class.

According to a third aspect of the present invention, in the first or second aspect, a copolymer of a methacrylate and an acrylate or a copolymer of methacrylates of different types is used. As a basic component, having a linear structure, and having a weight average molecular weight of 1,000,000 to
By adding the composition in the range of 5,000,000, a sufficient effect of improving the vacuum formability and the pressure forming property can be obtained.

According to the fourth aspect of the invention, the function of an extruded plate obtained from the flame-retardant thermoplastic resin composition according to any one of the first to third aspects is obtained.

[0021]

Embodiments of the present invention will be described below. The ABS resin used in the present invention includes:
In the presence of a rubbery polymer, styrene, an aromatic vinyl monomer represented by α-methylstyrene and the like, and acrylonitrile, a vinyl cyanide monomer represented by methacrylonitrile and the like are polymerized. And a free polymer containing no rubber obtained by polymerization of an aromatic vinyl monomer and a vinyl cyanide monomer. Examples of the rubbery polymer include a diene type and an acrylic type. ABS (acrylonitrile-butadiene-styrene) resin, AES (acrylonitrile-ethylene-propylene-diene-styrene) resin, A
AS (acrylonitrile-acrylstyrene) resin and the like are included.

A copolymer obtained by copolymerizing a third component copolymerizable with the above monomer component can also be used as an ABS resin. The type of the rubbery polymer may be a single type or a plurality of types. In addition to the ABS resin, an additive having a rubber component such as a so-called impact modifier may be used in combination.

As the ABS resin, those commercially available from various companies can be used. The composition and molecular weight of the ABS resin that can be used in the present invention are not particularly limited, but generally, the difference in flow characteristics from the polycarbonate resin under molding temperature and shear stress conditions in an extruder for thermoplastic resin. From the viewpoint, it is preferable that the weight average molecular weight of the AS resin (acrylonitrile / styrene copolymer resin) -free polymer is 150,000 or more. Further, the rubber content of the ABS resin is preferably 25% by weight or more from the viewpoint of not lowering the Izod (with notch) impact strength of the obtained composition, and AN from the viewpoint of compatibility with the PC resin.
The content of the resin (acrylonitrile resin) is preferably at least 23% by weight.

Various commercially available PC resins can be used. A structure having a bisphenol A skeleton as a main component and a carbonate bond in the main chain is generally used and can be suitably used. However, a PC resin having another structure may be used.

The molecular weight of the PC resin is preferably in the range of 23,000 to 30,000 in terms of the viscosity average molecular weight. If the molecular weight is smaller than this, the impact strength of the plate obtained from the composition is undesirably low. Further, when the molecular weight is larger than this, problems such as a decrease in fluidity, deterioration of extrusion moldability, and a significant difference in melt viscosity from ABS resin become difficult, and it is difficult to form a good alloy structure. Occurs and is not preferred.

The ratio between the PC resin and the ABS resin is 30 parts by weight based on 100 parts by weight of the total amount of both resins.
The range is preferably from 70 to 70 parts by weight and the amount of the PC resin from 70 to 30 parts by weight. When the amount of the ABS resin is larger than this, it is necessary to add a large amount of a flame retardant for flame retardation. As a result, physical properties such as impact strength are remarkably reduced, which is not preferable. On the other hand, if the amount of the ABS-based resin is smaller than this, it is not preferable because problems such as the thickness dependence of the impact strength and the decrease in elongation during heating and stretching become apparent.

From the viewpoint of exhibiting the characteristics of both the PC resin and the ABS resin, the ABS resin is 40 to 60 parts by weight,
The content of the PC resin is particularly preferably in the range of 60 to 40 parts by weight.
In the present invention, a specific acrylic copolymer and a specific bromine-based flame retardant are added to an alloy composition of a PC-based resin and an ABS-based resin having the above composition range,
A flame-retardant thermoplastic resin composition for extruded plates for molding, which has excellent secondary workability and a good balance of physical properties such as flame retardancy, impact strength, and heat distortion temperature.

That is, even if the PC-based resin and the ABS-based resin are simply alloyed to form a plate-shaped body, the vacuum / pressure forming properties thereof are not sufficient, and for the purpose of improving this,
Acrylic copolymer having a higher molecular weight than PC resin and ABS resin is used. Also, a problem of a resin composition containing a brominated flame retardant, which is a problem that occurs, such as a decrease in impact strength,
A specific flame retardant composition is used for the purpose of imparting sufficient flame retardancy while suppressing a decrease in pressure formability.

Examples of the acrylic copolymer having a higher molecular weight than the PC resin and the ABS resin include a copolymer of methacrylate and acrylate, or a different type of methacrylate (for example, methyl methacrylate and methacrylate). Butyl and the like, and a block copolymer and a random copolymer having a linear structure having a larger molecular weight than an ABS resin or a PC resin serving as a matrix resin.

The acrylic copolymer having the above constitution has good compatibility with both the PC resin and the ABS resin, so that when the acrylic copolymer is added to the PC / ABS alloy composition, the alloy composition is heated and kneaded. Entanglement between the constituent matrix resin (PC resin and ABS resin) and molecules,
The formation of the pseudo-crosslinking points produces effects such as an increase in melt tension and an increase in elongation at break during heat stretching.

As the acrylic copolymer having the above structure, a so-called processing aid used for improving the processability of a vinyl chloride resin can be suitably used. The preferred molecular weight range of the acrylic copolymer is 1,000,000 to 500
And more preferably 3,000,000 to 5,000,000.
When the molecular weight is smaller than this, the effect of entanglement becomes insufficient, it is difficult to obtain the effect of improving moldability at the time of vacuum forming, and even when the molecular weight is larger than this, the effect of breaking the molecular chains during heating and kneading becomes large, Alternatively, extrusion molding with an extruder having a low kneading degree is not preferred because sufficient molecular entanglement cannot be imparted.

The preferred amount of the acrylic copolymer is 1.0 to 10.0 parts by weight, more preferably 100 to 100 parts by weight of ABS resin and PC resin in total.
2.5 to 6.0 parts by weight. At less than this,
A sufficient effect of improving the vacuum formability and the compressed air formability cannot be obtained, and the addition of more than this is not preferable because the effect is saturated and only the cost is increased.

The flame retardant composition comprises 7.0 to 18.0 parts by weight of a bromine flame retardant having a bromine content of 60% or more and a melting point in the range of 180 ° C. to 240 ° C .; Of antimony trioxide (Sb ₂ O)
₃ ) Consists of However, the total amount of the PC resin and the ABS resin is 100 parts by weight.

By using a bromine-based flame retardant having a bromine content of 60% or more, a decrease in physical properties due to a large amount of addition can be suppressed, and by specifying the melting point range, it can be molecularly dispersed in the base resin and extruded. An example of a brominated flame retardant that does not cause a problem during molding but satisfies this condition is brominated triazine “Pyroguard” SR-245.
(Daiichi Kogyo Seiyaku).

The amount of the flame retardant main agent (bromine flame retardant) added depends on the required level of flame retardancy (flame retardant class), PC resin and ABS.
The necessary addition amount is determined by the ratio of the base resin, the degree of kneading during extrusion molding, the addition amount of the flame retardant aid, and the like. As the proportion of the flammable ABS resin increases, the amount added increases,
Increasing the amount of the flame retardant aid makes it possible to reduce the amount of the main agent added.

The preferred addition amount of the flame retardant is 7.0-1.
8.0 parts by weight (total amount of PC resin and ABS resin is 1
If it is less than this, it is difficult to impart sufficient flame retardancy, and if it is more than this, the resulting PC /
It is not preferable because the physical properties of the ABS alloy plate decrease. In addition, the value of 7.0% of the addition amount is UL94V-UL standard.
It is an estimated value from the oxygen index of each of the PC resin and the ABS resin to secure two classes.

Antimony trioxide, a flame retardant aid, is a flame retardant aid generally used in combination with a bromine-based flame retardant, and the amount of addition is determined according to a general flame retardant prescription. 1/5
Up to れ ば may be added, and if less than this, the flame retardancy is reduced, and if more than this, the effect of addition is saturated.

The smaller the particle size of antimony trioxide is, the less the impact strength of the obtained PC / ABS alloy plate is reduced. This is for the same reason as the impact strength reduction due to the molecular dispersion of the high-melting-point bromine-based flame retardant, but conversely, even if the particle size is too small, the specific surface area of the antimony trioxide particles increases. In addition, the heat degradation catalytic action on the PC-based resin becomes remarkable, which results in promoting the reduction of the molecular weight of the PC-based resin due to heating and kneading during extrusion molding, resulting in a reduction in impact strength.

In addition to the above components, the thermoplastic resin composition of the present invention may further comprise a lactone-based or phenol acrylate-based heat stabilizer, a phenol-based, phosphorus-based, polyphenol-based, tocopherol-based antioxidant, or a synthetic zeolite. It is preferable to add a halogen, a catalyst residue adsorbent, a metal catalyst deactivator, and the like. Further, if necessary, additives added to a plate material made of a usual thermoplastic resin such as an ultraviolet absorber, a lubricant, an antistatic agent, a pigment such as an extender pigment and a color pigment, and the like may be contained.

The plate obtained by extruding the resin composition of the present invention may be provided on one surface or both surfaces.
It may have a configuration in which a thermoplastic resin film or the like having a composition different from that of the composition of the present invention is laminated, or two or more layers having different compositions are formed within the scope of the claims of the present invention. You may.

(Examples) Hereinafter, the present invention will be described in more detail with reference to examples. Each sample used in Examples 1 to 3 and Comparative Examples 1 to 7 was prepared by the following method.

[Ingredients used in Examples 1 to 3 and Comparative Examples 1 to 7] (a) PC resin: NOVAREX 7027 (Mitsubishi Engineering Plastics) bisphenol A type Weight average molecular weight of about 27000 (b) ABS resin: UX-050 (A from Ube Sicon)
BS resin) and SR-65B (AS resin from Ube Sykon)
(C) Acrylic copolymer: (c) -A: Metablen P-531 (Mitsubishi Rayon)
Molecular weight 4.7 million (c) -B: Metablen P-551A (Mitsubishi Rayon)
Molecular weight 1.45 million (c) -C: Metablen P-550 (Mitsubishi Rayon)
Molecular weight 950,000 (d-1) Flame retardant agent: A: "Pyroguard" SR-245 (Daiichi Kogyo Pharmaceutical Co., Ltd.) Brominated triazine molecular weight 1067 Bromine content 67% Melting point 230 ° C B: Decabromo diphenyl ether molecular weight 959 bromine Content: 83% Melting point: 308 ° C. C: Brominated bisphenol A / epoxy oligomer type (I) Molecular weight: about 10,000 Bromine content: 52% Melting point: about 189
° C D: Brominated bisphenol A / epoxy oligomer type (II) Molecular weight about 3000 Bromine content 55% Melting point about 140
° C E: Brominated bisphenol A / epoxy oligomer type (III) Molecular weight about 1600 Bromine content 50% Melting point about 116
° C (d-2) Flame retardant aid: "Pyroguard" AN-800T (Daiichi Kogyo Seiyaku) Antimony trioxide (e) Other additive components: (e) -1: Heat stabilizer Irganox 1076: Irgafos 168 = 2: 1 blend product (Ciba Specialty Chemicals) (e) -2: Adsorbent MC-56G (Mitsui Organic Synthesis) Synthetic zeolite (e) -3: Lubricant METABLEN L-1000 (Mitsubishi Rayon) Acrylic lubricant The components are blended in the weight ratios shown in Tables 1 and 2,
Blend in 75 liter Henschel mixer.

[0043]

[Table 1]

[0044]

[Table 2] [Preparation of Plates Used in Examples 1 to 3 and Comparative Examples 1 to 7] The compounds shown in Tables 1 and 2 were extruded by a T-die by the following method to obtain plates having a thickness of 5.0 mm and 3.0 mm. I got a body.

Extruder: Cylinder inner diameter 65 mm, single axis vent type mouthpiece: lip width 460 mm, lip gap 5.5 mm
Extrusion moldability was good for Examples 1 to 3 and Comparative Examples 1 to 6, but for Comparative Example 7, poor feeding of the raw material powder occurred, and the amount of extrusion was large. Saw a significant drop. It is considered that a large amount of a low-melting-point flame retardant was added.

[Evaluation of Various Physical Properties] The extruded plates of the above Examples and Comparative Examples were evaluated for the following physical properties. <Izod impact strength> According to JIS-K-7110 (with V notch) measurement method, a plate having a thickness of 5.0 mm was used.
Measurement was performed at a measurement temperature of 23 ° C. in each direction of D and TD.

<Load Deflection Temperature> According to JIS-K-7207, a plate having a thickness of 5.0 mm was used, and the temperature was raised at a rate of 120 ° C.
/ Hr and a load of 181.3 N / cm ² .

<High-speed tensile test> JIS-K-7113
The tensile elongation at break was measured at a measurement temperature of 140 ° C., 160 ° C., 180 ° C., and 200 ° C. in each direction of MD and TD at a tensile speed of 50 cm / sec using a 5.0 mm thick plate.

<Evaluation of Vacuum Formability> Using a small vacuum forming machine, evaluation was performed using an extruded plate having a thickness of 3.0 mm × 400 mm × 600 mm. The vacuum forming was performed at a surface temperature of about 190 ° C. of the plate.

Vacuum forming was performed using a convex trapezoidal forming die to form a molded product V having the shape shown in FIG. The surface area of the molded article after vacuum molding was about 3.5 times that before molding, and the appearance (visual observation) and the change in thickness (measured by a micrometer) after molding were evaluated. The site where the thickness was measured is shown in FIG.

Visual evaluation of the appearance of the molded product was as follows: "O" indicates that the surface has no streaks or wrinkles and no break, and "X" indicates that the surface has breaks or has significant streaks or wrinkles. The middle one was marked with “△”.

Since it was difficult to measure the drawdown due to the heating of the heater as a numerical value, the drawdown was visually observed. Visual evaluation of the drawdown was performed by holding the periphery of the plate for evaluation in a mold of a vacuum forming machine, and the surface temperature of the plate was 190 °.
In the state heated to C, those that clearly caused a large bending were marked with “x”, those that could not be visually confirmed to be bent were marked with “○”, and those in the middle were marked with “△”.

<Evaluation of flammability> The flammability was evaluated according to the UL94 vertical combustion test. The sum of the first and second burning times (the burning time after the first flame contact x 5 times and the burning time after the second flame contact x 5 times), the presence or absence of dripping, UL
The class was shown.

[Results of Evaluation of Physical Properties] Tables 3 and 4 show the evaluation results of the physical properties of each of the examples and comparative examples. 2A to 2C show measurement results of the thickness distribution after vacuum forming.

[0055]

[Table 3]

[0056]

[Table 4] As is evident from the results of the high-speed tensile tests in Tables 3 and 4, Examples 1 to 3 using the compounded composition of the present invention show good elongation at break in the molding temperature range. On the other hand, in Comparative Example 1 in which the acrylic copolymer (C) was not added, sufficient elongation at break was not obtained, and good moldability was obtained even when the PC resin and the ABS resin were simply alloyed. Is not obtained.

Comparative Example 2 used an acrylic copolymer (C) having a lower molecular weight than the range of claim 3 of the present invention. Although the elongation at break was improved as compared with the case where no acrylic copolymer was added, Not enough.

In Comparative Examples 3 to 7, the molecular weight and the amount of the acrylic copolymer (C) were the same as in Example 1 except that the type of the flame retardant (d-1) was changed.・ Diphenyl ether (abbreviated as DBDE in Table 2)
In Comparative Example 3 using No. 3, the elongation at break was generally reduced, and there is a possibility that the particles of the flame retardant acted as a breaking start point.

Comparative Example 4 was obtained by adding the same amount of the oligomer type flame retardant (I) as the flame retardant of the example. The elongation at break shows the same value as in examples 1 to 3, but the bromine content Comparative Example 5 in which the addition amount of the flame retardant was increased so that
In Table 1, the elongation at break is slightly lowered, indicating that the addition of a large amount of the flame retardant deteriorates the moldability.

In Comparative Examples 6 and 7, another type of oligomer type flame retardant was added in such a manner that the bromine content was adjusted so that the bromine content was equal to that in the Example, and the results were also compared. The same tendency as in Example 5 is shown.

Tables 3 and 4 showing the evaluation results of vacuum formability
As is clear from the results of the visual evaluation of the drawdown of
In Examples 1 to 3 of the present invention, the bending was effectively suppressed, but in Comparative Example 1 in which the acrylic copolymer (C) was not added, significant bending occurred, and claims of the present invention were made. Also in Comparative Example 2 using the acrylic copolymer (C) having a molecular weight lower than the range of 3, a warp that can be visually confirmed is generated.

In Comparative Examples 3 to 6, no bending was observed, but in Comparative Example 7, bending was observed. This is thought to be related to the addition of a large amount of a flame retardant having a low melting point.
Further, as is apparent from the results of the visual evaluation of the appearance of the molded product, the molded products of Examples 1 and 2 of the present invention had a very good appearance. On the other hand, in the comparative example, a result correlated with the result of the high-speed tensile test was obtained.

As is clear from FIG. 2A, in Examples 1 to 3 of the present invention, the whole is relatively uniformly stretched.
The difference in thickness between locations is small. On the other hand, Comparative Example 1,
In FIG. 2, as is clear from FIG. 2 (b), the trapezoidal top surface is not stretched much and remains thick, but the vicinity near the side top surface is extremely stretched, and depending on the location, The difference in thickness is significant. In Comparative Example 1, the thinnest portion was broken.

Comparative Examples 3 to 7 are also correlated with the results of the high-speed tensile test. Although good results were obtained in Comparative Example 4 in which the amount of the flame retardant (d-1) was the same as in the Examples, In Comparative Examples 5 to 7 in which the amount of the flame retardant was increased, the difference in thickness depending on the location was slightly remarkable.

As is clear from Tables 3 and 4, in Examples 1 to 3, although the strength in the MD direction is large, sufficient strength is obtained also in the TD direction. In Comparative Examples 1 and 2 in which the type and amount of the flame retardant were the same as in the example, almost the same level of values were obtained.

On the other hand, in Comparative Example 3, the strength was slightly lower in both the TD direction and the MD direction, which is considered to be due to the effect of the particle dispersion of the high-melting flame retardant. In Comparative Example 4 using the oligomer type flame retardant (I), the value in the TD direction was reduced by half compared to the example, and in Comparative Example 5 in which the amount of the flame retardant was increased, the absolute value of the strength was also reduced. Comparative Example 6 shows a similar tendency.

In Comparative Example 7, in which a oligomer having a relatively low molecular weight was added among the oligomer type flame retardants, the absolute value of the strength and the directionality were at the same level as those of the example, but as described above, there was a problem at the time of extrusion molding. .

In the flammability test, except for Comparative Example 4,
Since the addition amount of the flame retardant was adjusted so that the bromine content of the flame retardant became equal, the combustion situation was almost the same. As a situation, the combustion stops immediately after the first flame contact and the continuation of the combustion for several seconds after the second flame contact is recognized. Except for Comparative Example 1, the UL class had a flammability of 94V-0 class. In Comparative Example 1, there was one in which the burning time was almost the same, but dripping occurred after the second flame contact, and the UL class was 94V-2 class. There is a possibility that the addition of the acrylic copolymer is suppressing the generation of drip.

In Comparative Example 4, the amount of the flame retardant added was basically insufficient, and the burning time was prolonged. In addition, dripping was observed, and the UL class was 94V-2 class.

Despite the fact that considerable amounts of various flame retardants having different melting points were added, no difference was observed in the deflection temperature under load between the examples and comparative examples. Table 5 summarizes the results of the above physical property evaluations.

[0071]

[Table 5] This embodiment has the following effects.

(1) A resin composition mainly composed of 30 to 70 parts by weight of an ABS resin and 70 to 30 parts by weight of a polycarbonate resin (total of 100 parts by weight) is added to the ABS resin and the polycarbonate. 1.0 to 10.0 parts by weight of a composition comprising an acrylic copolymer having a higher molecular weight than that of the base resin, a bromine content of 60% or more, and a melting point of 180 ° C to 240 ° C. A brominated flame retardant was added in an amount of 18 parts by weight or less and a flame retardant aid was added. Therefore, it is possible to obtain an extruded plate excellent in secondary workability such as vacuum formability and compressed air formability, and excellent in balance of various physical properties such as flame retardancy, impact strength, and heat deformation temperature.

(2) Since antimony trioxide is used as a flame retardant aid and the amount of addition is 1/5 or more of the amount of the above-mentioned brominated flame retardant, the use of a flame retardant aid which is easily available has a UL standard. Of the above-mentioned 94V-2 class.

(3) Since the amount of antimony trioxide to be added is 1/3 or less of the amount of the above-mentioned brominated flame retardant, deterioration in physical properties due to the addition of a large amount of antimony trioxide can be suppressed. (4) The composition comprising an acrylic copolymer has a linear structure with a copolymer of methacrylic acid ester and acrylic acid ester or a copolymer of different types of methacrylic acid ester as a basic component. In addition, since the weight-average molecular weight is in the range of 1,000,000 to 5,000,000, a linear composition is easily available, and a sufficient effect of improving vacuum formability and pressure forming property can be obtained.

The embodiment is not limited to the above, and may be embodied as follows, for example. ○ Fine antimony trioxide treated with a silane coupling agent is used as a flame retardant aid. PC / AB antimony trioxide used as a flame retardant aid
In order to uniformly disperse molecules in the S-based alloy plate, it is preferable to reduce the particle size of antimony trioxide. However, conventionally, even if the particle size is too small, the specific surface area of the antimony trioxide particles becomes large, so that the catalytic effect of heat deterioration on the PC-based resin becomes remarkable.
As a result, a reduction in the molecular weight of the C-based resin was promoted, resulting in a reduction in impact strength. To work around this problem,
Fine particle antimony trioxide subjected to a surface treatment is used.

As the surface treatment, treatments such as an epoxy silane treatment and an alkyl silane treatment using a silane coupling agent are performed. It has been confirmed that the treatment with the silane coupling agent has a sealing effect of a thermal degradation catalytic action, in addition to an improvement in dispersibility in the resin and an improvement in the affinity between the matrix resin and the particle surface.

Except for the type of antimony, each of the compositions having the same composition as that of the examples was subjected to surface treatment and was not subjected to the surface treatment.
After kneading at 0 ° C. for 20 minutes, the kneaded material was taken out, and the fluidity was measured by a flow tester. In addition, the fluidity was similarly measured with the same composition without adding antimony trioxide. The results are shown in FIG. In the display of the vertical and horizontal axes in FIG. 3, for example, 1.E + 01 represents 1 × 10 ¹ and 1.E +
04 represents 1 × 10 ⁴ .

When untreated antimony trioxide was used, the apparent viscosity was lower than when no antimony was added. This is because the molecular weight of PC was reduced by the catalytic action of thermal degradation, and the impact strength was reduced. On the other hand, when antimony trioxide having been subjected to surface treatment is used, the apparent viscosity is slightly lower than that without antimony added, but the apparent viscosity is slightly smaller than that of untreated antimony, and the decrease in the molecular weight of PC is suppressed. Was confirmed.

The flame-retardant aid is not limited to antimony trioxide, and other substances such as zinc borate-based ones may be used. Technical ideas (inventions) other than those described in the claims that can be grasped from the embodiment will be described below together with their effects.

(1) In the invention according to any one of claims 1 to 3, the ABS resin has a rubber content of 25% or more and an acrylonitrile resin content of 2% or more.
3% or more. In this case, the Izod (notched) impact strength is not reduced, and the compatibility with the polycarbonate resin is improved.

(2) In any one of claims 1 to 3 and (1), the ABS resin is
The weight average molecular weight of the acrylonitrile / styrene copolymer resin free polymer is 150,000 or more. In this case, the difference in the flow characteristics between the ABS-based resin and the polycarbonate-based resin under a molding temperature and a shear stress condition at the time of the extrusion molding by the extruder is reduced, and the moldability is further improved.

(3) Claims 1 to 3 and (1),
In any one of the inventions described in (2), the polycarbonate resin has a molecular weight of 2300 in terms of viscosity average molecular weight.
The range is from 0 to 30,000. In this case, problems such as a decrease in fluidity, deterioration in extrusion moldability, and difficulty in forming an alloy structure with the ABS resin are unlikely to occur, and there is no decrease in impact strength.

(4) In any one of the first to third aspects of the present invention, antimony trioxide surface-treated with a silane coupling agent is used as the flame retardant auxiliary. In this case, the catalytic effect of antimony trioxide on the thermal degradation of the PC resin is suppressed, and even if the particle size of antimony trioxide is reduced and the molecules are dispersed, the reduction in molecular weight due to heating and kneading during extrusion molding is promoted. Is prevented.

[0084]

As described in detail above, claims 1 to 4 are provided.
According to the invention described in (1), it is possible to obtain an extruded plate excellent in secondary workability such as vacuum formability and compressed air formability, and excellent in balance of various properties such as flame retardancy, impact strength, heat deformation temperature and the like. Can be.

According to the second aspect of the present invention, a flame retardant level higher than the UL standard of 94V-2 class can be achieved by using an easily available flame retardant aid. According to the third aspect of the present invention, the linear composition is easily available, and a sufficient effect of improving vacuum formability and pressure forming property can be obtained.

[Brief description of the drawings]

FIG. 1A is a schematic perspective view of a vacuum-formed molded product, and FIG. 1B is a cross-sectional view showing a thickness measurement site.

2A is a graph showing a thickness distribution of a molded article of each example, and FIGS. 2B and 2C are graphs showing a thickness distribution of a molded article of each comparative example.

FIG. 3 is a graph showing the effect of surface-treated antimony on fluidity.

[Explanation of symbols]

 V: Molded product.

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (reference) C08L 69/00 C08L 69/00 // (C08L 55/02 (C08L 55/02 69:00 69:00 33:06) 33:06) B29K 55:02 B29K 55:02 69:00 69:00 B29L 7:00 B29L 7:00 F term (reference) 4F207 AA13 AA21E AA28 AB05 AB06 AB07 AB21 AE10 AG02 AH46 KA01 KA17 KF02 KL41 KL84 KW41 4J002 BG043 BG053 BN06W BN12W BN15W CG00X CG01X DE127 ED076 EJ056 EU186 FD136 FD137

Claims (4)

[Claims] 1. An ABS resin of 30 to 70 parts by weight and a polycarbonate resin of 70 to 30 parts by weight (the total of both is 10 to 10 parts by weight).
0 to 1 part by weight), 1.0 to 10.0 parts by weight of a composition comprising an acrylic copolymer having a higher molecular weight than the ABS resin and the polycarbonate resin, and a bromine content. Is more than 60% and melting point is 180 °
A flame-retardant thermoplastic resin composition comprising 18 parts by weight or less of a bromine-based flame retardant in the range of C to 240 ° C. and a flame retardant aid. 2. The flame-retardant thermoplastic resin composition according to claim 1, wherein antimony trioxide is used as the flame-retardant aid, and the amount of the additive is not less than 1/5 of the amount of the bromine-based flame retardant. 3. The composition comprising an acrylic copolymer, comprising a copolymer of methacrylic acid ester and acrylic acid ester or a copolymer of methacrylic acid esters of different types as a basic constituent, The flame-retardant thermoplastic resin composition according to claim 1, having a structure, and having a weight average molecular weight in a range of 1,000,000 to 5,000,000. 4. An extruded flame-retardant thermoplastic resin sheet obtained by extruding the flame-retardant thermoplastic resin composition according to claim 1 into a plate shape using an extruder.