JP2001026704A - Flame-retardant polycarbonate resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a flame-retardant polycarbonate resin composition that has improved resistance to humidity, resistant to hydrolysis even when it is placed under high-humidity conditions, excellent transparency, high resistance to shock and to heat, and high thermal stability. SOLUTION: To 100 pts.wt. of a polycarbonate containing 0-80 wt.% of a straight-chain aromatic polycarbonate resin and 100-20 wt.% of an aromatic polycarbonate with a structural viscosity factor N of >=1.2, are formulated 0.1-15 pts.wt. of an organopolysiloxane and 0.01-5 pts.wt. of a metal organic sulfonate salt to give the objective polycarbonate resin composition. In this case, the organopolysiloxane has a weightaverage molecular weight of 400-1,500 and bears phenyl groups as essential substituents in the molecule, and the content of the organoxy group is <5 wt.%.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a flame-retardant polycarbonate resin composition. More specifically, a molded article made of the flame-retardant resin composition is hardly hydrolyzed even when placed under high humidity conditions, has improved hydrolysis resistance (moisture resistance), and further has a dripping prevention property during combustion. The present invention relates to an improved flame-retardant polycarbonate resin composition.

[0002]

2. Description of the Related Art Polycarbonate resins have excellent mechanical properties, and are widely used as materials for manufacturing parts in the fields of automobiles, office automation equipment, electric and electronic fields, and other industrial fields. On the other hand, there is a strong demand for flame-retardant synthetic resin materials as parts manufacturing materials, mainly for applications such as OA equipment and home appliances, and in order to meet these demands, a large number of flame retardants and flame-retardant resins Compositions have been developed and proposed.

In order to make polycarbonate resin flame-retardant,
Conventionally, compounds mainly containing halogen have been used. Halogen-containing compounds have drawbacks such as lowering the thermal stability of the resin composition containing them and corroding the screws and molding dies of molding machines. Therefore, for the purpose of reducing the amount of a compound containing a halogen, for example, a phosphate compound or a flame retardant composition using a combination of a phosphate compound and a phenol stabilizer has been proposed.
However, such a flame-retardant polycarbonate resin composition has a disadvantage that impact resistance and thermal stability are reduced.

As a technique for blending a compound containing no halogen into a base resin to make it flame-retardant, for example, an alkali (earth) metal salt of perfluoroalkanesulfonic acid, an alkoxy group as a substituent, A flame-retardant composition containing an organic siloxane having a vinyl group and a phenyl group has been proposed (Patent No. 2)
719486). The invention described in this publication intends to improve the flame retardancy by blending an organic siloxane containing a vinyl group as a substituent with a base resin. However, in this resin composition, the detailed structure of the organic siloxane used is not described, and the effect of improving the moisture resistance of the obtained resin composition is not sufficient.

On the other hand, JP-A-10-139964 discloses a flame-retardant resin obtained by adding a silicone resin having a weight-average molecular weight in the range of 10,000 to 270,000 to a non-silicone resin having an aromatic ring, which functions as a flame retardant. A composition is described. In the flame-retardant resin composition described in this publication, the flame retardancy of the non-silicone resin having an aromatic ring as the base resin is improved, but since the molecular weight of the silicone resin to be compounded is high, this molecular weight is high. When a silicone resin is mixed with a polycarbonate resin, there is a disadvantage that the transparency inherent in the polycarbonate resin itself is impaired.
In addition, when the alkoxy group content of the silicone resin having an alkoxy group is high, when the flame-retardant resin composition or a molded product obtained therefrom is placed under a high humidity condition, moisture is easily absorbed and transparency is greatly increased. (Inferior in moisture resistance).

[0006]

The objects of the present invention are as follows. 1. It is difficult to hydrolyze even when placed under high humidity conditions,
To provide a flame-retardant polycarbonate resin composition having improved hydrolysis resistance (moisture resistance). 2. To provide a flame-retardant polycarbonate resin composition excellent in impact resistance, heat resistance, heat stability and the like. 3. An object of the present invention is to provide a flame-retardant polycarbonate resin composition in which the use amount of a compound containing halogen is reduced as much as possible and the problem of corrosion of a molding machine screw, a molding die and the like is largely improved.

[0007]

In order to solve the above-mentioned problems, according to the present invention, a linear aromatic polycarbonate resin having 0 to 80% by weight and an aromatic polycarbonate resin having a structural viscosity index N of 1.2 or more are provided. Flame retardancy in which 0.1 to 15 parts by weight of an organopolysiloxane and 0.01 to 5 parts by weight of a metal salt of an organic sulfonic acid are blended with 100 parts by weight of a total of 100 to 20% by weight of a base resin. In the reactive polycarbonate resin composition, the organopolysiloxane has a weight average molecular weight of 400 to 1500, has a phenyl group as an essential substituent in the molecule, and has a content of an organooxy group of less than 5% by weight. The present invention provides a flame-retardant polycarbonate resin composition, characterized in that:

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail.
The aromatic polycarbonate resin in the present invention constitutes the base resin of the flame-retardant polycarbonate resin composition, and is produced by reacting an aromatic hydroxy compound or a small amount thereof with a phosgene or carbonic acid diester. And a thermoplastic aromatic polycarbonate polymer or copolymer which may be branched. The method for producing the resin is not particularly limited, and the resin can be produced by a conventional method such as a phosgene method (interfacial polymerization method) or a melting method (ester exchange method). Further, an aromatic polycarbonate resin produced by adjusting the amount of terminal OH groups by a melting method may be used.

The aromatic dihydroxy compounds include 2,2.
2-bis (4-hydroxyphenyl) propane (= bisphenol A), tetramethylbisphenol A, bis (4-hydroxyphenyl) -P-diisopropylbenzene, hydroquinone, resorcinol, 4,4-dihydroxydiphenyl, and the like. Of these, bisphenol A is particularly preferred.

In order to control the molecular weight of the aromatic polycarbonate resin, a monovalent aromatic hydroxy compound may be used, and m- and p-methylphenol, m- and p-
-Propylphenol, p-tert-butylphenol,
And p-long chain alkyl-substituted phenols.

The aromatic polycarbonate resin is preferably a polycarbonate resin derived from 2,2-bis (4-hydroxyphenyl) propane or 2,2-bis (4-hydroxyphenyl) propane.
Examples include polycarbonate copolymers derived from 2-bis (4-hydroxyphenyl) propane and other aromatic dihydroxy compounds. The aromatic polycarbonate resin may be a mixture of two or more polymers and / or copolymers having different raw material components. For the purpose of further increasing the flame retardancy, a compound in which one or more tetraalkylphosphonium sulfonates are bonded to the aromatic dihydroxy compound and / or a polymer or oligomer having a siloxane structure can be copolymerized.

The molecular weight of the linear aromatic polycarbonate resin is determined at a temperature of 25 using methylene chloride as a solvent.
It is preferable that the viscosity average molecular weight calculated from the solution viscosity measured at 0 ° C is in the range of 16,000 to 30,000, and particularly preferable is 18,000 to 26,000.
00 range. The structural viscosity index N of this linear aromatic polycarbonate resin is preferably 1.1 or less.

The aromatic polycarbonate resin having a structural viscosity index N of 1.2 or more constituting the base resin of the flame retardant polycarbonate resin composition includes a branched aromatic polycarbonate resin. As described in JP-A-8-245782, by selecting catalyst conditions or production conditions, a melt method (ester exchange method) can be carried out without adding a branching agent.
An aromatic polycarbonate resin having a high structural viscosity index and excellent hydrolysis stability can be obtained.

In the present invention, the “structural viscosity index N” is
Literature (Shigeharu Onoki, Rheology for Chemists, 1
Formulas (1.15) and (1.15) described in pages 5 to 16).
7) The stress σ is eliminated from the equation, and a straight line approximation between two points of a predetermined γ is obtained from the equation to obtain the slopes (1−N) / N and N.
The inclination can be evaluated in a low-shear step region where the viscosity behavior is greatly different. Incidentally, γ = 12.16 sec ^-1
And η at γ = 24.32 sec ⁻¹ can determine the N value.

[0015]

(Equation 1)

[0016]

(Equation 2)

[0017]

(Equation 3)

[0018]

(Equation 4)

[0019]

(Equation 5)

(In the above formula, N is the structural viscosity index, a is a constant, ηa is the apparent viscosity, and η is the viscosity.)

When an aromatic polycarbonate resin having a structural viscosity index N of 1.2 or more is produced by a melting method, a branching agent may be used. If necessary, for example,
The following compounds can also be used in place of part of the aromatic dihydroxy compound. Specific examples of the compound include phloroglucin, 4,6-dimethyl-2,4,
6-tri (4-hydroxyphenyl) heptene-2,
4,6-dimethyl-2,4,6-tri (4-hydroxyphenyl) heptane, 2,6-dimethyl-2,4,6-
Tri (4-hydroxyphenylheptene-3,1,3,
5-tri (4-hydroxyphenyl) benzene, 1,
Polyhydroxy compounds such as 1,1-tri (4-hydroxyphenyl) ethane, or 3,3-bis (4-hydroxyaryl) oxindole (= isatin bisphenol), 5-chlorisatin bisphenol, , 7-Dichlorisatin bisphenol, 5-
Bromoisatin bisphenol and the like. The amount used is in the range of 0.01 to 10 mol%, particularly preferably in the range of 0.1 to 2 mol%.

Similarly, in the phosgene method (interface method),
By using the compounds listed above in place of part of the aromatic dihydroxy compound, a branched aromatic polycarbonate resin can be obtained.

The aromatic polycarbonate resin having a structural viscosity index N of 1.2 or more has a viscosity average molecular weight of 16,000 to 100 calculated from a solution viscosity measured at a temperature of 25 ° C. using methylene chloride as a solvent. , 00
A range of 0 is preferable, and a range of 18,000 to 30,000 is particularly preferable.

The base resin of the flame-retardant polycarbonate resin composition according to the present invention comprises 0 to 80% by weight of a linear aromatic polycarbonate resin and 20 to 100 of an aromatic polycarbonate resin having a structural viscosity index N of 1.2 or more. % By weight. In consideration of impact resistance, fluidity, and the like of the resin composition, it is preferable to mix an aromatic polycarbonate resin having a high structural viscosity index N.

The flame-retardant polycarbonate resin composition according to the present invention comprises the above-mentioned aromatic polycarbonate resin as the base resin and an organopolysiloxane having a specific structure. As the organopolysiloxane having a specific structure, one having a phenyl group as an essential substituent in the molecule is used. In addition, a substituent other than a phenyl group may be contained. The phenyl group as a substituent of the organopolysiloxane functions to improve the compatibility between the organopolysiloxane and the aromatic polycarbonate resin and to improve the flame retardancy of the resin composition.

The above-mentioned organopolysiloxane is GPC
Weight average molecular weight of 400 to 1500
Shall be selected from the range of When the molecular weight of the organopolysiloxane is less than 400, the content of the low-molecular-weight compound increases, and the component which volatilizes out of the system when melt-mixed with the polycarbonate resin of the base resin increases, thereby exhibiting a flame retardant effect. And the molecular weight is 1500
When it exceeds, the dispersibility in the base resin becomes poor, and the transparency and impact strength of the molded article obtained from the finally obtained flame-retardant resin composition are reduced, and the surface transfer property during combustion is reduced. It becomes worse and the expected combustion effect is not exhibited, which is not preferable. The weight average molecular weight of the organopolysiloxane is
Preferably it is 400 to 1400, more preferably 5
00 to 1300.

In the organopolysiloxane, the proportion of the phenyl group in the total weight of all the organic groups bonded to the silicon atom and all the substituents including the organic group bonded to the silicon atom via the oxygen atom of the organooxy group is as follows. , 30 to 70% by weight. If the proportion of the phenyl group in all the substituents in the organopolysiloxane molecule is less than 30% by weight, the flame retardant effect of the finally obtained flame retardant resin composition will not be sufficiently exerted, and the base resin The compatibility with the aromatic polycarbonate resin is reduced, resulting in non-uniform dispersion, which causes a deterioration in appearance (transparency), impact resistance, and the like of a molded product obtained from the flame-retardant resin composition. On the other hand, if the ratio of the phenyl group to all the substituents exceeds 70% by weight, the compatibility of the base resin with the aromatic polycarbonate resin becomes too high, and the surface transfer during combustion becomes poor. The combustion effect will be reduced.

It is preferable that the organopolysiloxane further has an alkoxy group content of less than 5% by weight in the molecule. The alkoxy group in the organopolysiloxane exerts an effect of suppressing drip during combustion.On the other hand, when the flame-retardant resin composition or a molded article obtained therefrom is placed under high humidity conditions, In addition, there is a possibility that the hydrolysis reaction with the absorbed moisture generates an alcohol, thereby inferior in moisture resistance and impair the transparency of the molded article. Therefore, from the viewpoint of moisture resistance, the content of the alkoxy group in the molecule of the organopolysiloxane is set to less than 5% by weight to reduce the amount of the alkoxy group contributing to the above hydrolysis reaction, whereby the flame-retardant resin composition is obtained. It is possible to greatly improve the moisture resistance of the product or a molded product obtained therefrom, and to obtain a molded product excellent in transparency.

The organopolysiloxane containing a phenyl group in the molecule and having an alkoxy group content of less than 5% by weight is essentially non-reactive and has high heat resistance. Therefore, the structure hardly changes in a temperature range of 300 ° C. or lower, and thus it can be used as a raw material resin for producing a flame-retardant polycarbonate resin molded product that can be reused (recycled). The alkoxy group has 2 to 3 carbon atoms selected from an isopropoxy group, a 2-butoxy group, a tert-butoxy group, a cyclohexyloxy group and the like from the viewpoint of reactivity and flame retardancy.
It is preferably a primary and / or tertiary alkoxy group.

Further, the organopolysiloxane has a hydroxyl group content as a Si—OH group contained in its molecule of 2%.
% By weight or less is preferred. This is because, when the content of the hydroxyl group contained in the molecule exceeds 2% by weight, a condensation reaction between Si-OH groups tends to occur when melt-mixed with the polycarbonate resin of the base, and the organopolysiloxane has a high molecular weight. In addition, the dispersibility becomes poor, and the transparency and impact strength of the finally obtained flame-retardant resin composition and molded article are reduced, and the surface transfer property during combustion is deteriorated, and the flame retardancy is also reduced. Because.

The organopolysiloxane as an essential component in the present invention can be easily produced by a conventionally known method. That is, according to the molecular structure and molecular weight of the target organopolysiloxane, an appropriate alcohol and water are reacted with an organochlorosilane having a phenyl group, and then, if necessary, an organic solvent added, hydrochloric acid produced as a by-product, and low boiling water. By removing the component, an organopolysiloxane containing a phenyl group can be produced. In the case where the alkoxysilane having a phenyl group is used as a starting material, it can be produced by a method in which a predetermined amount of water is added and the hydrolysis reaction proceeds similarly according to the molecular weight of the target organopolysiloxane. In this case, an acid catalyst such as hydrochloric acid or acetic acid or a basic catalyst such as ammonia or sodium hydroxide can be used.

In this case, the content of the residual alkoxy group is reduced by using various silylating agents,
It is preferable to cap the generated Si-OH group, and by removing impurities such as by-produced alcohol, an organopolysiloxane can be similarly produced. In any case, the content of the phenyl group, the type and content of the alkoxy group, and the molecular weight can be easily adjusted by selecting the type and amount of each raw material.

A phenyl group or an alkoxy group as a substituent contained in the molecule of the organopolysiloxane is represented by N
It can be measured by MR. Si contained in the molecule
The content (% by weight) of the hydroxyl group as an —OH group can be measured by reacting a predetermined amount of an organopolysiloxane with a methyl Grignard reagent and quantifying the generated methane gas according to the Grignard method.

The flame-retardant polycarbonate resin composition according to the present invention comprises an aromatic polycarbonate resin 10 as a base resin.
The above organopolysiloxane was added in an amount of 0.1 part by weight to 0 part by weight.
It is blended in the range of 1 to 15 parts by weight. If the amount is less than 0.1 part by weight, the flame retardant effect of the finally obtained flame retardant resin composition is insufficient, and if it exceeds 15 parts by weight, the flame retardant effect is not improved. In addition, mechanical properties such as impact strength are significantly reduced, which is not preferable. The compounding amount of the organopolysiloxane is preferably 0.2 to 10
Parts by weight, more preferably 0.3 to 5 parts by weight.

The flame-retardant polycarbonate resin composition according to the present invention further contains a metal salt of an organic sulfonic acid.
Examples of the organic sulfonic acid metal salt include an aliphatic sulfonic acid metal salt and an aromatic sulfonic acid metal salt. The metal of the organic sulfonic acid metal salt preferably includes an alkali metal, an alkaline earth metal and the like. Alkali metals and alkaline earth metals include sodium, lithium, potassium, rubidium, cesium, beryllium,
Magnesium, calcium, strontium and barium and the like. The metal organic sulfonic acid salt may be a mixture of two or more kinds.

Examples of the organic sulfonic acid metal salt include perfluoroalkane-sulfonic acid metal salt, aromatic sulfone sulfonic acid metal salt and the like. Among them, preferred is
The former is a perfluoroalkane-sulfonic acid metal salt. Specific examples of perfluoroalkane-sulfonic acid metal salts include perfluoroalkane-sulfonic acid alkali metal salts and perfluoroalkane-sulfonic acid alkaline earth metal salts. Among them, preferred is
Examples thereof include alkali metal sulfonic acid salts having a perfluoroalkane group having 1 to 8 carbon atoms, and alkaline earth metal sulfonic acid salts having a perfluoroalkane group having 1 to 8 carbon atoms.

Specific examples of perfluoroalkane-sulfonic acid include perfluoromethane-sulfonic acid, perfluoroethane-sulfonic acid, perfluoropropane-sulfonic acid, perfluorobutane-sulfonic acid, perfluorohexane-sulfonic acid, Perfluoroheptane-sulfonic acid, perfluorooctane-sulfonic acid and the like can be mentioned.

Preferred examples of the metal salt of aromatic sulfonsulfonic acid include alkali metal salts of aromatic sulfonsulfonic acid and alkaline earth metal salts of aromatic sulfonesulfonic acid. The alkaline earth metal sulfonate sulfonate may be a polymer.

Specific examples of the metal salt of aromatic sulfonsulfonic acid include sodium salt of diphenylsulfon-3-sulfonic acid, potassium salt of diphenylsulfon-3-sulfonic acid, and 4,4′-dibromodiphenyl-sulfon-3.
Sodium salt of sulfone, potassium salt of 4,4′-dibromodiphenyl-sulfone-3-sulfone, calcium salt of 4-chloro-4′-nitrodiphenylsulfon-3-sulfonic acid, diphenylsulfone-3,3′-disulfone Disodium salt of acid, diphenyl sulfone-3
And dipotassium salt of 3'-disulfonic acid.

The amount of the metal organic sulfonic acid is based on 100 parts by weight of the aromatic polycarbonate resin as the base resin.
It shall be selected in the range of 0.01 to 5 parts by weight. When the amount of the organic sulfonic acid metal salt is less than 0.01 parts by weight,
The flame retardancy of the finally obtained flame-retardant resin composition is not sufficient, and if it exceeds 5 parts by weight, the thermal stability decreases, and neither is preferred. The amount of the organic sulfonic acid metal salt is preferably 0.01 to 4 parts by weight in the above range, and particularly preferably 0.02 to 3 parts by weight.

The flame-retardant polycarbonate resin composition according to the present invention may contain, if necessary, stabilizers such as ultraviolet absorbers, antioxidants and heat stabilizers, pigments, dyes, lubricants, flame retardants other than those described above, Additives such as anti-drip agents, release agents, and slidability improvers, glass fibers, glass flakes, carbon fibers, potassium titanate, aluminum borate, whiskers, and other reinforcing materials, or aromatic polycarbonates constituting the base resin A thermoplastic resin other than the resin can be added and blended.

Other thermoplastic resins that can be blended include polyester resins such as polybutylene terephthalate and polyethylene terephthalate, nylon 6, nylon 6 and the like.
・ Polyamide resin such as 6, rubber-reinforced polystyrene,
Thermoplastic resins such as styrene resins such as ABS resins and polyolefin resins such as polyethylene and polypropylene are exemplified. The blending amount of the other thermoplastic resin is 40% by weight or less, more preferably 30% by weight or less, of the finally obtained flame-retardant polycarbonate resin composition.

In the flame-retardant polycarbonate resin composition according to the present invention, the base resin as a main component is preferably an aromatic polycarbonate resin containing no halogen,
In addition, it is preferable that the components containing halogen be minimized in the components contained in the base resin or be non-halogen compounds. A flame-retardant resin composition in which such a compound containing halogen has been reduced as much as possible or a non-halogen compound has a small decrease in heat stability, impact resistance and heat resistance,
The problem of corrosion of the screw and the molding die of the molding machine and the problem of environmental pollution hardly occur, which is preferable.

The method for preparing the flame-retardant polycarbonate resin composition according to the present invention is not particularly limited. For example, (1)
A method of weighing predetermined amounts of an aromatic polycarbonate resin, an organopolysiloxane and a metal sulfonic acid salt of a base resin, and further, if necessary, other additives, etc., and mixing and kneading them all at once, (2) fragrance of the base resin. A method of melt-kneading an aromatic polycarbonate resin, an organopolysiloxane, a metal sulfonic acid salt and the like in advance, and further blending other additives as necessary, and then melt-kneading.

Mixing and kneading at the time of preparing the flame-retardant polycarbonate resin composition according to the present invention are carried out by a conventionally known mixer / kneader, for example, a ribbon blender, a Henschel mixer, a Banbury mixer, a single screw. It can be performed using an extruder, a twin-screw extruder, a multi-screw extruder, a co-kneader or the like. The heating temperature at the time of kneading varies depending on the type and ratio of the raw materials constituting the flame-retardant polycarbonate resin composition.
It is selected in the range of 40 to 300 ° C.

The flame-retardant polycarbonate resin composition according to the present invention thus obtained can be obtained by an extrusion molding method, an injection molding method,
A molded product such as a target product or part can be easily manufactured by a conventionally known molding method such as a compression molding method, a blow molding method, a gas injection molding method, and a precision injection molding method. The obtained molded product has mechanical strength, heat resistance, moisture resistance,
It has excellent properties such as heat stability during molding, as well as excellent surface appearance, flame retardancy, and non-drip properties during combustion of molded products. It can be used as a material for manufacturing products and parts in a wide range of fields such as the home appliance field.

[0047]

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to the following description unless it departs from the gist.

The components used in the examples and comparative examples are as follows. (1) Linear aromatic polycarbonate resin: poly-4,4
-Isopropylidene diphenyl carbonate,
The viscosity average molecular weight is 21,000 and the structural viscosity index N is 1.
0 (Mitsubishi Engineering Plastics,
Trade name: Iupilon S-3000, hereinafter referred to as "linear P
C ”). (2) Polycarbonate resin having a structural viscosity index N of 1.2 or more: prepared by the method described in the following synthesis examples of N-PC-1 to N-PC-3 (hereinafter, "N-PC")
Abbreviated).

(3) Organopolysiloxane: Organopolysiloxanes (S-1 to S-5) having various physical properties shown in Table 1 were synthesized according to the above-mentioned method for producing an organopolysiloxane. The phenyl group content (% by weight) in all the substituents in each organopolysiloxane
And the alkoxy group content (% by weight) in the molecule was measured by NMR, and the weight average molecular weight was measured by GPC. Furthermore, the hydroxyl group content (% by weight) as a Si—OH group in the molecule was measured by reacting a predetermined amount of an organopolysiloxane with a methyl Grignard reagent and quantifying the generated methane gas according to the Grignard method. (4) Metal salt of organic sulfonic acid-1: potassium perfluorobutanesulfonic acid (F-114, manufactured by Dainippon Ink and Chemicals, Inc.).

[0050]

[Table 1]

The physical properties of the obtained flame-retardant polycarbonate resin composition were evaluated by the methods described below. (a) Flammability test: UL 1.6 mm and 1.2 mm thick
A vertical combustion test was performed on the standard test piece. For the UL class, "V0" passes V0, "V2" passes V2,
"V2NG" means that V2 is not passed, respectively. (b) Deflection temperature under load (° C.): Using a bending test piece having a thickness of 6.4 mm, the deflection temperature under a load of 18.5 kg / cm ² was measured.

(C) Izod impact strength (kg-cm / cm ² ): Impact strength was measured on an impact test piece having a thickness of 3.2 mm and a 0.25R notch cut. (d) Haze of molded article (%): A pressure cooker (hereinafter, referred to as a 3 mm thick plate molded by an injection molding machine)
PCT) (after "PCT") and after a test at 120 ° C for 5 hours ("P
After CT), the haze was measured with a haze meter. The greater the value after PCT, the lower the moisture resistance of the molded product.

<N-PC having a structural viscosity index N of 1.2 or more
Synthesis of N-PC-1] Bisphenol A (BPA) and diphenyl carbonate (DPC) in a nitrogen gas atmosphere
And a molten mixture obtained by mixing and adjusting a constant molar ratio (DPC / BPA = 1.040) at a flow rate of 88.7 kg / hr, at a normal pressure and a nitrogen atmosphere at 140 ° C. under a nitrogen atmosphere through a raw material introduction pipe. The liquid was continuously supplied into one vertical stirring polymerization tank, and the liquid level was kept constant while controlling the valve opening provided in the polymer discharge line at the bottom of the tank so that the average residence time was 60 minutes. At the same time as starting the supply of the raw material mixture, a 0.02 wt% cesium carbonate aqueous solution was used as a catalyst at a rate of 320 ml / hr (1 × 10 ⁻⁶ mol per mol of BPA).
At a constant flow rate.

The polymerization liquid discharged from the bottom of the first polymerization tank was continuously and successively supplied to the second, third, and fourth vertical polymerization tanks and the fifth horizontal polymerization tank arranged in series. In each tank, the liquid level was controlled so that the average residence time was 60 minutes during the reaction, and at the same time, the by-product phenol was distilled off. The polymerization conditions were respectively set in the second polymerization tank (220
C, 100 Torr, 160 rpm), third polymerization tank (240 C,
15 Torr, 130 rpm), 4th polymerization tank (270 ° C, 0.5
Torr, 44 rpm), 5th polymerization tank (285 ° C, 0.5 Torr,
5 rpm), and the conditions were set to a high temperature, a high vacuum, and a low stirring speed with the progress of the polymerization reaction.

The production rate of polycarbonate is 50 kg / h
r. The viscosity average molecular weight (Mv) of the polycarbonate resin thus obtained was 27000. The obtained polycarbonate resin is supplied in a molten state to a twin-screw extruder having a three-stage vent port and having an acidic compound injection hole in front of the vent port closest to the resin supply port, and continuously supplying the acidic compound. Solution (acetone 600ml, pure water 500m
l, 7 g of butyl paratoluenesulfonate) were added at a flow rate of 35 g / hr, and the mixture was devolatilized and pelletized. When the structural viscosity index N of the obtained branched polycarbonate resin (N-PC-1) was measured by the above-mentioned evaluation method, it was 1.46.

[Synthesis of N-PC-2] Under a nitrogen gas atmosphere, bisphenol A (BPA) and diphenyl carbonate (DPC) are mixed at a fixed molar ratio (DPC / BPA =
1.08.7) and the molten mixture was adjusted to 88.7 kg / h.
At a flow rate of r, under normal pressure and nitrogen atmosphere through the raw material introduction pipe,
The liquid was continuously supplied into the first vertical stirring polymerization tank controlled at 210 ° C., and the liquid level was controlled while controlling the valve opening provided on the polymer discharge line at the bottom of the tank so that the average residence time was 60 minutes. Kept constant. At the same time as starting the supply of the raw material mixture, a 0.02 wt% cesium carbonate aqueous solution was used as a catalyst at a rate of 320 ml / hr (per mole of BPA,
(1 × 10 ⁻⁶ mol).

The polymerization liquid discharged from the bottom of the first polymerization tank was continuously and successively supplied to the second, third and fourth vertical polymerization tanks and the fifth horizontal polymerization tank arranged in series. In each tank, the liquid level was controlled so that the average residence time was 60 minutes during the reaction, and at the same time, the by-product phenol was distilled off. The polymerization conditions were set in the second polymerization tank (210
C, 100 Torr, 200 rpm), third polymerization tank (240 C,
15 Torr, 100 rpm), 4th polymerization tank (270 ° C, 0.5
Torr, 44 rpm), 5th polymerization tank (285 ° C, 0.5 Torr,
55 rpm), and the conditions were set to high temperature, high vacuum, and low stirring speed as the polymerization reaction progressed.

The production rate of polycarbonate is 50 kg / h
r. M of the polycarbonate resin thus obtained
v was 22,500. The obtained polycarbonate resin is supplied in a molten state to a twin-screw extruder having a three-stage vent port and having an acidic compound injection hole in front of the vent port closest to the resin supply port, and continuously supplying the acidic compound. (600 ml of acetone, 500 ml of pure water, 7 g of butyl paratoluenesulfonate) was added at a flow rate of 35 g / hr, devolatilized and pelletized. When the structural viscosity index N of the obtained branched polycarbonate resin (N-PC-2) was measured by the above-mentioned evaluation method, it was 1.28.

[Synthesis of N-PC-3] In a reaction vessel equipped with a stirrer, 250 kg of BPA, 1.678 kg of 1,1,1-tris (4-hydroxyphenyl) -ethane as a branching agent, 1220 l of aqueous sodium hydroxide solution and chloride 550 liters of methylene and 450 liters of deionized water were charged. While stirring the contents of the reaction vessel, 123 kg of phosgene was blown thereinto, the aqueous phase and the organic phase were separated, and the upper solution was collected.
100 liters of deionized water, 275 liters of methylene chloride, and 6.414 kg of p-tert-butylphenol were respectively charged and allowed to stand for 5 minutes, and then stirred for 10 minutes.
Triethylamine was added, and a polycondensation reaction was performed for 1 hour.

The obtained reaction solution was allowed to stand and separated into an aqueous phase and an organic phase containing the produced polymer. The upper solution was collected, and 800 l of methylene chloride was added thereto while stirring, followed by discharging.
After washing with water and an acid, methylene chloride was removed from the obtained organic phase under reduced pressure to obtain a branched polycarbonate resin having Mv of 26,600. When the structural viscosity index N of the obtained branched polycarbonate resin (N-PC-3) was measured by the above-mentioned evaluation method, it was 1.39.

Examples 1 to 5 PCs (N-PC-1, N-PC-) having a structural viscosity index N of 1.2 or more with respect to 0 to 100 parts by weight of a linear aromatic polycarbonate resin.
2, N-PC-3), the organopolysiloxanes (S-1 to S-5) listed in Table 1, and metal salts of organic sulfonic acids were weighed at the ratios shown in Table 2, respectively. Mix by tumbler for 20 minutes. The obtained mixture was melted and kneaded by a twin screw extruder having a cylinder temperature of 270 ° C. and a diameter of 30 mm to form pellets. Using the obtained pellets as raw materials, combustion test pieces having thicknesses of 1.6 mm and 1.2 mm were molded by an injection molding machine having a cylinder temperature of 270 ° C. Further, with the same injection molding machine, the cylinder temperature was set to 270 ° C., and an Izod impact test piece, a bending test piece, and a plate having a thickness of 3 mm were formed. The above-described evaluation test was performed on the obtained test piece and plate. Table 2 shows the evaluation test results.

Comparative Examples 1 to 3 In the example described in Example 1, except that the kind and the amount of the organopolysiloxane were changed as shown in Table 2, the same as in Example 1 was used. A pellet was formed by the procedure, a test piece was formed, and an evaluation test was similarly performed on the obtained test piece. Table 2 shows the evaluation test results.

[0063]

[Table 2]

The following is clear from Tables 1 and 2. (1) An organopolysiloxane compounded in an aromatic polycarbonate resin as a base resin has one or more methoxy groups as substituents.
% (Examples 1 and 2), and when the alkoxy group is 2% by 2-butoxy group (Example 3), the resulting flame-retardant polycarbonate resin compositions all have an impact strength. And flame retardancy is V-0 even with test pieces of different thickness
The molded article before and after PCT had a low haze and was excellent in moisture resistance.

(2) A material obtained by changing the branched PC-1 to the branched PC-3 produced by the phosgene method (Example 4), and a material comprising only the branched PC-2 produced by the melting method (Example 5) All were good in flame retardancy, impact resistance and moisture resistance. (3) On the other hand, from the formulation of Example 1, the branched PC
With the material excluding -1 (Comparative Example 1), the flammability at 1.2 mm is V-2 (drop cotton ignition), which is not sufficient from the viewpoint of flame retardancy. From Example 5 and Comparative Example 1, when it is necessary to improve the flammability of a thinner molded product, it is necessary to mix an aromatic polycarbonate resin having a structural viscosity index N of 1.2 or more. I understand.

(4) Further, when the molecular weight of the organopolysiloxane was as large as 1600 (Comparative Example 2), the impact strength was low, and the flame retardancy was inferior to V-2 in any thickness of the test piece. The haze before PCT of the molded article is large and the transparency is poor. From these results, it can be seen that in order to improve the moisture resistance (change in haze before and after PCT) of the molded article, it is preferable that the molecular weight of the organopolysiloxane be 1000 or less. (5) When a compound containing 36% of a methoxy group as a substituent and 40% of a phenyl group is blended as an organopolysiloxane (Comparative Example 3), the haze before PCT of the molded article is low and the transparency is low. Although unaffected, the haze after PCT is high and the moisture resistance is poor. From these results, it can be seen that in order to improve the moisture resistance (change in haze before and after PCT) of the molded article, it is necessary to reduce the amount of the alkoxy group as a substituent of the organopolysiloxane.

[0067]

As described in detail above, the present invention has the following particularly advantageous effects, and its industrial value is extremely large. 1. The flame-retardant polycarbonate resin composition according to the present invention uses an aromatic polycarbonate resin containing 20% by weight or more of a branched aromatic polycarbonate resin having a structural viscosity index N of 1.2 or more as a base resin. In addition to its excellent mechanical strength, it exhibits excellent flame retardancy even with thin molded products. 2. The molded article obtained from the flame-retardant polycarbonate resin composition according to the present invention, since the organopolysiloxane and the metal salt of the organic sulfonic acid are blended in a specific range, even when placed under high humidity conditions. Hard to hydrolyze,
Excellent moisture resistance.

3. The flame-retardant polycarbonate resin composition according to the present invention has excellent compatibility between the base resin and the organopolysiloxane, and therefore has excellent mechanical strength such as impact resistance. 4. The flame-retardant polycarbonate resin composition according to the present invention is excellent not only in flame retardancy in a thin molded product, but also in heat stability and impact strength. 5. The flame-retardant polycarbonate resin composition according to the present invention is characterized in that a halogen-free polycarbonate resin is used as a base resin, and a halogen-free organic sulfonic acid metal salt is combined. Corrosive problems such as are greatly improved.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Kuniyo Mimura 5-6-1-2 Higashi-Hachiman, Hiratsuka-shi, Kanagawa Prefecture Inside the Technology Center of Mitsubishi Engineering-Plastics Corporation (72) Inventor Takashi Miyajima 5 Higashi-Yawata, Hiratsuka-shi, Kanagawa 6-6-2 Mitsubishi Engineering Plastics Corporation Technology Center F term (reference) 4J002 CG01W CG01X CG03W CP033 CP063 EV256 FD133 FD136 GN00 GQ00

Claims (7)

[Claims] 1. A straight-chain aromatic polycarbonate resin
A total of 100 parts by weight of a base resin comprising 80% by weight and 100 to 20% by weight of an aromatic polycarbonate resin having a structural viscosity index N of 1.2 or more, 0.1 to 15 parts by weight of an organopolysiloxane, Sulfonic acid metal salt
In the flame-retardant polycarbonate resin composition, each of which contains 0.01 to 5 parts by weight, the organopolysiloxane has a weight average molecular weight of 400 to 1500 and has a phenyl group as an essential substituent in the molecule, and A flame-retardant polycarbonate resin composition having a content of an organooxy group of less than 5% by weight. 2. A linear aromatic polycarbonate resin having a viscosity average molecular weight of 16,000 to 30,000.
The flame-retardant polycarbonate resin composition according to claim 1. 3. An aromatic polycarbonate resin having a structural viscosity index N of 1.2 or more has a viscosity average molecular weight of 1
The flame-retardant polycarbonate resin composition according to claim 1 or 2, which has a molecular weight of 6,000 to 100,000. 4. The organopolysiloxane has a phenyl group in the total weight of all organic groups bonded to a silicon atom and all substituents including an organic group bonded to a silicon atom via an oxygen atom of the organooxy group. The flame-retardant polycarbonate resin composition according to any one of claims 1 to 3, wherein the proportion is 30 to 70% by weight. 5. The method according to claim 5, wherein the residual organooxy group of the organopolysiloxane is a secondary and / or tertiary group having 3 to 6 carbon atoms.
The flame-retardant polycarbonate resin composition according to any one of claims 1 to 4, which is a higher-grade alkoxy group. 6. An organopolysiloxane containing S in the molecule.
The flame-retardant polycarbonate resin composition according to any one of claims 1 to 5, which contains a hydroxyl group as an i-OH group in a range of 2% by weight or less. 7. The flame-retardant polycarbonate resin composition according to claim 1, wherein the metal organic sulfonic acid salt is a perfluoroalkane-sulfonic acid metal salt.