JPH07118485A - Low-gloss thermoplastic resin composition - Google Patents

Abstract

PURPOSE:To obtain a thermoplastic composition having low glossiness and excellent mechanical properties and weather resistance by compounding a polycarbonate resin containing a specific composite rubber-based graft copolymer with a specific addition polymer and a specific compound. CONSTITUTION:This thermoplastic resin composition is produced by compounding (A) 100 pts.wt. of a composition composed of (a) a polycarbonate resin and (b) a composite rubber-based graft copolymer obtained by grafting a vinyl monomer to a composite rubber composed of (i) a polyorganosiloxane rubber component having the unit of the formula I, II or III (R<1> is lower alkyl; R<2> is H or CH3; (n) is 0-2; (p) is 1-6) and (ii) a polyalkyl (meth)acrylate rubber component with (B) 1-30 pts.wt. of an addition polymer containing a unit derived from glycidyl (meth)acrylate and (C) 0.001-1 pt.wt. of an organic acid, phosphoric acid, (hypo)phosphorous acid and/or a compound having functional group selected from amino, OH, etc., and other than organic acid.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a low gloss aromatic polycarbonate resin composition.

[0002]

2. Description of the Related Art Aromatic polycarbonate is
It is widely used because of its excellent mechanical strength, weather resistance, light stability and heat resistance, but its molded product often has luster. While glossy is desirable for some applications, matte or matte surfaces are often preferred in products such as computer terminal housings, typewriters, numerous electrical appliances and certain automotive parts.

Surface embossing is one of the methods for removing the gloss of a molded product, but this method requires a separate step, which increases the cost. Moreover, subsequent abrasion can cause the embossed matte surface to disappear, recreating the gloss. On the other hand, the addition of matting agents such as finely divided silica, silicates, alumina or other mineral fillers often adversely affects physical properties such as impact strength of molded articles. Attempts to add polymeric matting agents can also sometimes adversely affect not only impact strength, but also physical properties such as heat distortion temperature, weather resistance, photostability, and other important properties. .

As an aromatic polycarbonate resin composition having low gloss and excellent mechanical strength and heat resistance, a composition obtained by blending a butadiene rubber polymer and other components is disclosed in, for example, JP-A-59-193950. Bulletin,
It is known from JP-A-60-020955, JP-A-61-174257 and JP-A-63-156851. But,
Polycarbonate-based resin compositions containing butadiene-based rubber polymers often show insufficient weather resistance and are therefore not suitable for applications requiring high weather resistance. As described above, it has been difficult for a conventional polycarbonate resin composition to simultaneously satisfy excellent mechanical properties, excellent weather resistance and low gloss.

Therefore, an object of the present invention is to provide a polycarbonate resin composition having low gloss and excellent mechanical properties and weather resistance.

[0006]

The present inventors have found that an addition polymer containing a unit derived from glycidyl (meth) acrylate in an aromatic polycarbonate resin containing a specific composite rubber-based graft copolymer, and It was found that the addition of a compound having a specific acid or a specific group can reduce the gloss without impairing the characteristics of the aromatic polycarbonate resin composition.

That is, the present invention relates to a composite rubber system obtained by grafting a vinyl monomer onto a composite rubber containing (A) (1) a polycarbonate resin and (2) a polyorganosiloxane and a polyalkyl (meth) acrylate. With respect to 100 parts by weight of the composition comprising the graft copolymer, (B) 1 to 30 parts by weight of an addition polymer containing a unit derived from glycidyl (meth) acrylate and (C) (i) an organic acid, ( ii) phosphoric acid, (iii) phosphorous acid, (iv) hypophosphorous acid, and / or
(v) A thermoplastic resin composition comprising 0.001 to 1 part by weight of a compound other than an organic acid having at least one functional group selected from the group consisting of an amino group, a hydroxyl group, an acid anhydride group and a mercapto group. Provide things.

Here, the above-mentioned component (A) (2) and the component
The combined use of (B) and (C) is an important requirement of the present invention. With these combinations, the gloss can be significantly reduced without impairing the excellent mechanical properties and weather resistance of the polycarbonate-based resin. This is totally unexpected.

The polycarbonate resin as the component (A) (1) used in the present invention is an aromatic polycarbonate produced by a known phosgene method or a melting method (see, for example, JP-A-63-215763). Kaihei 2-124934 reference). The polycarbonate resin is composed of a carbonate component and a diphenol component. Examples of the precursor for introducing the carbonate component include phosgene and diphenyl carbonate. Suitable diphenols include, for example, 2,2-bis (4-hydroxyphenyl) propane (so-called bisphenol A); 2,2-
Bis (3,5-dibromo-4-hydroxyphenyl) propane; 2,2-bis (3,5-dimethyl-4-hydroxyphenyl)
Propane; 1,1-bis (4-hydroxyphenyl) cyclohexane; 1,1-bis (3,5-dimethyl-4-hydroxyphenyl) cyclohexane; 1,1-bis (4-hydroxyphenyl) decane; 1,4 -Bis (4-hydroxyphenyl) propane; 1,1-bis (4-hydroxyphenyl) cyclododecane; 1,1-bis (3,5-dimethyl-4-hydroxyphenyl)
Cyclododecane; 4,4-dihydroxydiphenyl ether; 4,4-thiodiphenol; 4,4-dihydroxy-3,3-dichlorodiphenyl ether; and 4,4-dihydroxy-
2,5-dihydroxydiphenyl ether and the like can be mentioned. These can be used alone or in combination.
In addition to this, it is also possible to use a compound having three or more phenolic hydroxyl groups.

Next, the component (A) (2) used in the present invention
I will describe. Component (A) (2) is, for example, JP-A-64-79257
In a composite rubber having a structure in which a polyorganosiloxane rubber component and a polyalkyl (meth) acrylate rubber component are alternately intertwined with each other to be compositely integrated as described in Japanese Patent Publication No. It is a composite rubber-based graft copolymer obtained by graft-polymerizing a vinyl-based monomer.

It is suitable that such a composite rubber is produced by an emulsion polymerization method. First, a latex of polyorganosiloxane rubber is prepared, and then a monomer for synthesizing an alkyl (meth) acrylate rubber is impregnated into rubber particles of the polyorganosiloxane rubber latex. It is preferred to polymerize the monomer.

The polyorganosiloxane rubber component can be prepared by emulsion polymerization using, for example, the following organosiloxane and cross-linking agent (I), in which case a graft crossing agent (I) can be used in combination. .

Examples of the organosiloxane include chain organosiloxanes such as dimethylsiloxane. Further, various cyclic organosiloxanes having a 3-membered ring or more, preferably a 3 to 6-membered ring can also be used. Examples thereof include hexamethylcyclotrisiloxane, octamethylcyclotetrasiloxane, decamethylcyclopentasiloxane, dodecamethylcyclohexasiloxane, trimethyltriphenylcyclotrisiloxane, tetramethyltetraphenylcyclotetrasiloxane and octaphenylcyclotetrasiloxane. These organosiloxanes may be used alone or in admixture of two or more. The amount of these used is preferably 50% by weight or more, and more preferably 70% by weight or more in the polyorganosiloxane rubber component.

The cross-linking agent (I) may be trifunctional or tetrafunctional.
Functional silane-based crosslinking agents such as trimethoxymethylsilane, triethoxyphenylsilane, tetramethoxysilane, tetraethoxysilane, tetra-n-propoxysilane, tetrabutoxysilane and the like can be used.
Particularly, a tetrafunctional crosslinking agent is preferable, and tetraethoxysilane is particularly preferable. The crosslinking agents may be used alone or in combination of two or more. The amount of the crosslinking agent used is 0.1 to 30% by weight in the polyorganosiloxane rubber component.
Is preferred.

The graft crossing agent (I) has the following formula:

[0016]

Embedded image CH ₂ ═C (R ² ) —COO— (CH ₂ ) _p —SiR ¹ _n O _{(3-n) / 2} (I-1)

[0017]

Embedded image CH ₂ ═CH—SiR ¹ _n O _{(3-n) / 2} (I-2) or

[0018]

Embedded image HS- (CH ₂ ) _p —SiR ¹ _n O _{(3-n) / 2} (I-3) (In the above formula, R ¹ is a lower alkyl group such as a methyl group,
Represents an ethyl group, a propyl group or the like or a phenyl group, R ²
Represents a hydrogen atom or a methyl group, and n is 0, 1 or 2
And p represents an integer of 1 to 6) is used. Since the (meth) acryloyloxysiloxane capable of forming the unit of the above formula (I-1) has high grafting efficiency, it is possible to form an effective graft chain, which is advantageous in that it exhibits high impact resistance. Is. In addition, methacryloyloxysiloxane is particularly preferable as a unit capable of forming the unit of the formula (I-1). Specific examples of methacryloyloxysiloxane include β-methacryloyloxyethyldimethoxymethylsilane, γ-methacryloyloxypropylmethoxydimethylsilane, γ-methacryloyloxypropyldimethoxymethylsilane, γ-methacryloyloxypropyltrimethoxysilane, γ-methacryloyloxypropyl silane. Examples thereof include ethoxydiethylsilane, γ-methacryloyloxypropyldiethoxymethylsilane and δ-methacryloyloxybutyldiethoxymethylsilane. These may be used alone or in combination of two or more. The amount of the graft crossing agent used is preferably 0 to 10% by weight in the polyorganosiloxane rubber component.

For the production of the latex of the polyorganosiloxane rubber component, the method described in, for example, US Pat. Nos. 2891920 and 3294725 can be used. In the practice of the present invention, for example, an organosiloxane, a cross-linking agent (I), and optionally a mixed solution of a graft crossing agent (I), an alkylbenzene sulfonic acid,
It is preferably produced by a method of shear mixing with water in the presence of a sulfonic acid-based emulsifier such as an alkyl sulfonic acid using, for example, a homogenizer. Alkylbenzene sulfonic acid is suitable because it acts as an emulsifier of the organosiloxane and at the same time serves as a polymerization initiator. At this time, it is preferable to use a metal salt of alkylbenzene sulfonic acid, a metal salt of alkyl sulfonic acid, or the like, because it is effective in maintaining the polymer stably during the graft polymerization.

Next, the polyalkyl (meth) acrylate rubber component constituting the above composite rubber may be synthesized by using the following alkyl (meth) acrylate, crosslinking agent (II) and graft crossing agent (II). it can.

As the alkyl (meth) acrylate,
Examples thereof include alkyl acrylates such as methyl acrylate, ethyl acrylate, n-propyl acrylate, n-butyl acrylate, and 2-ethylhexyl acrylate, and hexyl methacrylate, 2-ethylhexyl methacrylate, alkyl methacrylates such as n-lauryl methacrylate, and particularly n-butyl. The use of acrylates is preferred.

Examples of the cross-linking agent (II) include ethylene glycol dimethacrylate, propylene glycol dimethacrylate, 1,3-butylene glycol dimethacrylate, and 1,4-butylene glycol dimethacrylate.

Examples of the graft crossing agent (II) include allyl methacrylate, triallyl cyanurate, triallyl isocyanurate and the like. Allyl methacrylate can also be used as a cross-linking agent. These crosslinking agents and graft crossing agents may be used alone or in combination of two or more. The total amount of the cross-linking agent and the graft crossing agent used is preferably polyalkyl (meth)
It is 0.1 to 20% by weight in the acrylate rubber component.

The polymerization of the polyalkyl (meth) acrylate rubber component is carried out by adding the above alkyl (meth) acrylate into the latex of the polyorganosiloxane rubber component neutralized by the addition of an aqueous solution of an alkali such as sodium hydroxide, potassium hydroxide or sodium carbonate. ) An acrylate, a crosslinking agent and a graft crossing agent are added and impregnated into the polyorganosiloxane rubber particles, and then a normal radical polymerization initiator is allowed to act. As the polymerization proceeds, a crosslinked network of polyalkyl (meth) acrylate rubber entwined with each other is formed in the crosslinked network of polyorganosiloxane rubber, and it is practically impossible to separate.
A latex of a composite rubber of a polyorganosiloxane rubber component and a polyalkyl (meth) acrylate rubber component is obtained. In the practice of the present invention, as the composite rubber, the main skeleton of the polyorganosiloxane rubber component has a repeating unit of dimethylsiloxane, and the main skeleton of the polyalkyl (meth) acrylate rubber component is a repeating unit of n-butyl acrylate. A composite rubber having is preferably used.

The composite rubber thus prepared by emulsion polymerization can be graft-copolymerized with a vinyl monomer. The gel content measured by extracting this composite rubber with toluene at 90 ° C. for 12 hours is preferably 80% by weight or more.

The ratio of the polyorganosiloxane rubber component and the polyalkyl (meth) acrylate rubber component in the above composite rubber is preferably 3 to 90% by weight for the former and 97 to 10% by weight for the latter. The average particle size of the composite rubber is preferably 0.08 to 0.6 μm.

Vinyl-based monomers to be graft-polymerized on the above composite rubber include styrene, α-methylstyrene,
Aromatic alkenyl compounds such as vinyltoluene; methacrylic acid esters such as methyl methacrylate and 2-ethylhexyl methacrylate; acrylic acid esters such as methyl acrylate, ethyl acrylate and butyl acrylate; vinyl cyanide compounds such as acrylonitrile and methacrylonitrile. Examples thereof include vinyl monomers, which may be used alone or in combination of two or more. A particularly preferred vinyl monomer is methyl methacrylate. The vinyl-based monomer is the above-mentioned composite rubber 30-
It is preferably contained in a proportion of 5 to 70% by weight with respect to 95% by weight.

The composite rubber-based graft copolymer is a composite rubber-based graft copolymer latex obtained by adding the above-mentioned vinyl-based monomer to the above-mentioned composite rubber latex and polymerizing it in a single stage or multiple stages by a radical polymerization technique. It can be separated and recovered by pouring it into hot water in which a metal salt such as calcium chloride or magnesium sulfate is dissolved and salting out and coagulating.

Such a composite rubber-based graft copolymer is commercially available from, for example, Mitsubishi Rayon Co., Ltd.
It is commercially available as 2001.

The above component (A) (2) is the component (A) (1) 2
80 to 1% by weight, preferably 0 to 99% by weight,
(A) (1) It is mixed in a proportion of 70 to 10% by weight with respect to 30 to 90% by weight. If the blending amount of (A) (2) is too small, the gloss will not be lowered so much, and if it is too large, heat resistance and rigidity will tend to be lowered.

Next, the component (B) used in the present invention will be described. In the present invention, the component (B) addition polymer containing units derived from glycidyl (meth) acrylate includes all polymers containing units derived from glycidyl (meth) acrylate, In addition to homopolymers of glycidyl acid (GMA) or glycidyl acrylate and copolymers thereof, copolymers with other monomers may be used. When the component (B) is a copolymer, such a copolymer preferably contains 1% by weight or more of a unit derived from glycidyl (meth) acrylate, and more preferably 2 to 30% by weight. %contains.
As other constituent monomers, aromatic vinyl compounds (eg styrene), vinyl cyanide compounds (eg acrylonitrile), unsaturated carboxylic acids (eg (meth) acrylic acid) or their alkyl esters (eg methyl methacrylate, acrylic acid) A compound selected from the group consisting of methyl) can be used alone or in combination of two or more. More preferably, GMA-styrene copolymer, GMA-styrene-acrylonitrile copolymer,
Used as component (B). These components (B) are the components (A)
(That is, the total of the components (A) (1) and (A) (2)) is blended in an amount of 1 to 30 parts by weight, preferably 3 to 20 parts by weight, per 100 parts by weight. When the amount of the component (B) is less than 1 part by weight, the gloss does not decrease so much, and when it exceeds 30 parts by weight, the mechanical strength of the composition decreases.

The compound used as the component (C) is (i) organic acid, (ii) phosphoric acid, (iii) phosphorous acid, (iv) hypophosphorous acid,
Alternatively, (v) a compound other than an organic acid, which is a compound having at least one functional group selected from the group consisting of an amino group, a hydroxyl group, an acid anhydride group and a mercapto group.
Only one of these compounds may be used, or two or more thereof may be used in combination. The (i) organic acid used here is not particularly limited, and various known ones can be used. Examples include acetic acid, propionic acid, malonic acid, succinic acid, stearic acid, maleic acid, fumaric acid, itaconic acid, citric acid, benzoic acid, phthalic acid, isophthalic acid,
Examples thereof include, but are not limited to, carboxylic acids such as terephthalic acid, and sulfonic acids such as benzenesulfonic acid and toluenesulfonic acid. These organic acids may further have other functional groups such as an amino group, a hydroxyl group, an acid anhydride group and a mercapto group. (ii) Phosphoric acid, (iii) phosphorous acid, and (iv) hypophosphorous acid are all well known and need not be particularly described here. (v) The compound having one or more functional groups selected from the group consisting of an amino group, a hydroxyl group, an acid anhydride group and a mercapto group may have, for example, two or more such functional groups. The two or more functional groups may be the same or different. Moreover, you may have another functional group. Examples of these compounds include diethylenetriamine, m-phenylenediamine, hexamethylenediamine, hydroxyethylmethacrylate, maleic anhydride, phthalic anhydride, hexahydrophthalic anhydride,
Pyromellitic dianhydride, dodecyl succinic anhydride, ethanethiol, phenylthiol and the like can be mentioned, but not limited thereto. Ingredient (C) is based on 100 parts by weight of ingredient (A) (that is, the sum of ingredients (A) (1) and (A) (2)).
It is contained in the resin composition of the present invention in an amount of 0.001 to 1 part by weight, preferably 0.01 to 0.5 part by weight. Component (C) is 0.0
If it is less than 01 parts by weight, the gloss of the composition is not sufficiently reduced, and if it exceeds 1 part by weight, the properties of the composition such as mechanical strength and heat resistance are deteriorated.

Further, the resin composition of the present invention contains other resins, particularly rubber-like substances, conventional additives such as pigments, dyes, reinforcing agents and fillers at the time of mixing and molding of the resins as long as the physical properties thereof are not impaired. , Heat-resistant agents, antioxidants, weathering agents, lubricants, mold release agents, crystal nucleating agents, plasticizers, fluidity improvers,
Antistatic agents and the like can be added.

Reinforcing fillers include finely ground aluminum, iron or nickel, metal oxides and non-metals such as carbon filaments, silicates such as mica, aluminum silicate (clay), talc, asbestos, titanium dioxide, Selected from wollastonite, novaculite, potassium titanate and titanate whiskers, glass flakes, glass beads and glass fibers and polymer fibers,
Alternatively, it may be a combination of these.

The reinforcing filler may be used in an amount capable of exerting a reinforcing action, and is usually 1 to 60% by weight based on the total weight of the composition. The preferred range is 5 to 50% by weight. The preferred toughening agent is glass.

When the composition of the present invention contains a polycarbonate composed of brominated bisphenol, an inorganic or organic antimony compound is further added to the composition of the present invention in order to synergistically enhance the flame retardancy achieved thereby. You can

As stabilizers and antioxidants, hindered phenols, phosphites, metal phosphates, metal phosphites and the like can be mixed.

In producing the resin composition of the present invention, the respective components can be mixed by a conventionally known method. For example, a method in which each component is dispersed and mixed by a turnable mixer, a Henschel mixer, a ribbon blender, a high speed mixer typified by a super mixer, and then melt-kneaded by an extruder, a Banbury mixer, a roll or the like is appropriately selected.

[0039]

EXAMPLES In the following examples and comparative examples, the following components were used. Component (A) (1): Aromatic Polycarbonate (PC): Lexan 141 (Trademark;
General Electric Co., manufactured from bisphenol A and phosgene, intrinsic viscosity in methylene chloride at 25 ° C .: 0.51 dl / g) Component (A) (2): METABLEN S-2001: Trademark, methyl methacrylate-butyl acrylate -Dimethylsiloxane copolymer, manufactured by Mitsubishi Rayon Co., Ltd. Component (B): G-1005SA (trademark; manufactured by NOF Corporation, 5% by weight GM)
A-containing styrene-acrylonitrile-based copolymer) G-1005S (trademark; NOF Corporation, 5 wt% GMA)
Styrene-based Copolymer Contained) Component (C): Citric Acid, Phosphorous Acid, Maleic Anhydride Other Components (Used in Comparative Examples) ABS Resin: Bredex 301 [Trademark; Borg Wagner Chemical Co., about 24% Powdered ABS copolymer containing acrylonitrile monomer units, 34% butadiene monomer units and 42% styrene monomer units (rubber content 34
%)] Examples 1 to 5 and Comparative Examples 1 to 10 Components in the proportions (weight ratios) shown in Table 1 are melt-kneaded at a kneading temperature of 260 ° C and a rotation speed of 290 rpm in a 50 mm twin-screw extruder to prepare pellets. It was Using this pellet, set temperature 260
A molded product was prepared under the conditions of ℃ and mold temperature of 60 ℃, and the physical properties were measured according to the following criteria. -Notched Izod impact strength ... ASTM D256-Tensile strength and tensile elongation ... ASTM D638-Bending strength and flexural modulus ... ASTM D790 The results are shown in Tables 1 and 2.

Further, the glossiness of the surface of the molded product (50 × 50 × 3 mm square plate) was measured using a digital variable angle gloss meter (UGV-40, manufactured by Suga Test Instruments Co., Ltd.). The results are also shown in Tables 1 and 2.

Furthermore, a gray colored molded product (50 × 50
* 3 mm square plate, made in the same way as the molded product used for measuring glossiness), weather tester (Ci35 manufactured by Atlas Co., Ltd.)
Type), and a black panel temperature of 63 ° C. and a humidity of 50% were used to perform irradiation with a xenon arc lamp with an emission wavelength of 340 nm and irradiance of 0.39 W / m ² . Then, the color difference value (ΔE) with respect to the initial hue was measured using a spectrophotometer (CA35 type manufactured by Murakami Color Research Laboratory). The results are also shown in Tables 1 and 2.

[0042]

[Table 1]

[0043]

[Table 2]

[0044]

EFFECTS OF THE INVENTION According to the present invention, it is possible to provide an aromatic polycarbonate resin composition having a sufficiently low glossiness and excellent mechanical strength and weather resistance.

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Claims (3)

[Claims] 1. A composite rubber-based graft copolymer obtained by grafting a vinyl-based monomer onto a composite rubber containing (A) (1) a polycarbonate resin and (2) a polyorganosiloxane and a polyalkyl (meth) acrylate. Based on 100 parts by weight of the composition comprising the polymer, (B) an addition polymer containing a unit derived from glycidyl (meth) acrylate 1 to 30
Parts by weight and (C) (i) organic acid, (ii) phosphoric acid, (iii) phosphorous acid, (iv) hypophosphorous acid, and / or (v) amino group,
A compound other than an organic acid having at least one functional group selected from the group consisting of a hydroxyl group, an acid anhydride group and a mercapto group.
A thermoplastic resin composition comprising 0.001 to 1 part by weight. 2. An aromatic vinyl compound in which the addition polymer containing a unit derived from glycidyl (meth) acrylate (B) contains 1% by weight or more of a unit derived from glycidyl (meth) acrylate. The thermoplastic resin composition according to claim 1, which is a polymer of a compound selected from the group consisting of a vinyl cyanide compound and an unsaturated carboxylic acid or an alkyl ester compound thereof. 3. The component (A) is (1) a polycarbonate resin.
Composition consisting of 99 to 20% by weight and (2) 1 to 80% by weight of a composite rubber graft copolymer obtained by grafting a vinyl monomer to a composite rubber containing a polyorganosiloxane and a polyalkyl (meth) acrylate. Claim 1 which is a thing
The thermoplastic resin composition described.