JP2005263902A - Transparent thermoplastic resin composition and molded product - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide transparent thermoplastic resin compositions having good color tone and well balanced and excellent weather resistance, impact resistance and rigidity, and to provide molded products comprising the composition. <P>SOLUTION: The transparent thermoplastic resin composition and molded products contain, based on 100 pts.wt. rubber-reinforced styrene copolymer (I), 0.01-3 pts.wt. ultraviolet light absorber (II) and 0.01-3 pts.wt. specific phosphorus compound (III), wherein the contents of (II) and (III) satisfy 0.1<content of (III)/content of (II)<2. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a transparent thermoplastic resin composition having good color tone and excellent balance of weather resistance, impact resistance and rigidity, and a molded article comprising the same.

  Rubber polymers such as diene rubbers, aromatic vinyl such as styrene and α-methylstyrene; unsaturated carboxylic acid esters such as methyl methacrylate; vinyl monomers such as vinyl cyanide such as acrylonitrile and methacrylonitrile A rubber-reinforced styrene-based thermoplastic resin using a rubber-containing graft copolymer obtained by graft copolymerization is excellent in impact resistance, moldability, appearance, and the like. And widely used in various applications such as general goods. Some of these rubber-reinforced styrene resins have high transparency, and these are widely used in fields such as toys and building materials.

  As a method for imparting weather resistance to this rubber-reinforced styrene-based thermoplastic resin, a method of blending a UV absorber such as a benzotriazole type (for example, see Non-Patent Document 1) is generally used. When it is applied to rubber-reinforced styrene-based thermoplastic resins that have the properties, the appearance and color tone of the molded product are important, but yellowing occurs due to the addition of such UV absorbers, and the appearance There was a problem that was disturbed.

  Further, as shown in Patent Document 1, a rubber-reinforced styrene-based thermoplastic resin having excellent weather resistance obtained by using an acrylic rubber as a rubber polymer (for example, see Patent Document 1) is known. However, this resin has a problem in terms of balance of physical properties such as extremely poor impact resistance.

Furthermore, a method for imparting impact resistance without reducing the weather resistance and transparency of an acrylic resin using an enlarged polybutadiene rubber is also known (for example, see Non-Patent Document 2). However, there was a problem that transparency and weather resistance were still insufficient.
By Management Development Center Publishing Department Polymer troubleshooting / disintegration trouble countermeasures and latest reforming / stabilizing technology comprehensive collection (P863) JP-A-12-26618 (Claim 1) JP-A-10-245468 (Claim 1)

  An object of the present invention is to provide a transparent thermoplastic resin composition that eliminates the above-mentioned drawbacks of the prior art, has good color tone, and is well balanced in weather resistance, impact resistance, and rigidity, and a molded article comprising the same. There is.

  As a result of intensive studies to achieve the above object, the present inventors have blended a specific phosphorus compound into a rubber-reinforced styrene-based transparent resin containing an ultraviolet absorber, so that the color tone is good, weather resistance, The present inventors have found that a transparent thermoplastic resin composition and a molded product having excellent balance of impact resistance and rigidity can be obtained, and the present invention has been made.

  That is, in order to achieve the above object, according to the present invention, there is provided a resin composition containing a rubber-reinforced styrene copolymer (I) reinforced with a rubbery polymer, comprising an acetone-soluble resin component and acetone. The refractive index difference of the insoluble resin component is less than 0.03, and the acetone-soluble resin component contained in the resin composition is an aromatic vinyl monomer (a1) of 5 to 70% by weight, an unsaturated carboxylic acid. Acid alkyl ester monomer (a2) 30 to 95% by weight, vinyl cyanide monomer (a3) 0 to 50% by weight and other monomers copolymerizable therewith (a4) 0 to 50% % Of the UV-absorbing agent (II) in an amount of 0.01 to 3 parts by weight based on 100 parts by weight of the rubber-reinforced styrene copolymer (I). A phosphorus compound (III) represented by the formula 1 to 3 parts by weight, and the content of the ultraviolet absorber (II) and the phosphorus compound (III) is the formula 0.1 <content of phosphorus stabilizer (III) (parts by weight) / ultraviolet absorption A transparent thermoplastic resin composition satisfying the content (parts by weight) <2 of the agent (II) is provided.

  (In the formula, R 1 and R 2 represent an alkyl group having 1 to 25 carbon atoms or a substituted or unsubstituted phenyl group.)

In the transparent thermoplastic resin composition of the present invention,
Furthermore, it contains at least one stabilizer selected from phosphorus stabilizers (IV) other than the phosphorus compound (III), phenol stabilizers (V) and sulfur stabilizers (VI),
Presence of 10 to 95 parts by weight of a copolymer (A) obtained by copolymerizing the vinyl monomer mixture (a) with the rubber-reinforced styrene copolymer (I) and a rubbery polymer (b) A rubber-containing graft copolymer (B) formed by graft polymerization of a vinyl-based monomer mixture (c) below, comprising 90 to 5 parts by weight;
The vinyl-based monomer mixture (a) and the vinyl-based monomer mixture (c), which are raw materials for the rubber-reinforced styrene-based copolymer (I), are aromatic vinyl-based monomers (a1) of 5 to 70 weights. %, Unsaturated carboxylic acid alkyl ester monomer (a2) 30 to 95% by weight, vinyl cyanide monomer (a3) 0 to 50% by weight and other monomers copolymerizable therewith (a4) ) Having a monomer composition consisting of 0 to 50% by weight, and substantially comprising an unsaturated carboxylic acid monomer (excluding the unsaturated carboxylic acid alkyl ester monomer (a2)) (a5) The monomer mixture does not contain,
The ultraviolet absorber (II) is a compound (VII) represented by the following formula 2, and

(In the formula, R 1 and R 2 represent an alkyl group having 1 to 25 carbon atoms or a substituted or unsubstituted phenyl group.)
A preferable condition is that the difference in refractive index between the acetone-soluble resin component and the acetone-insoluble resin component is less than 0.03.

  Moreover, the molded article of the present invention is characterized by comprising the above-described transparent thermoplastic resin composition.

  According to the present invention, as described below, it is possible to obtain a transparent thermoplastic resin composition having a good color tone and excellent balance of weather resistance, impact resistance and rigidity, and a molded product comprising the same.

  The present invention will be specifically described below.

  The resin composition containing the rubber-reinforced styrene copolymer (I) referred to in the present invention is a resin composition containing a styrene copolymer imparted with impact resistance by a rubbery polymer. However, the rubbery polymer contains aromatic vinyl monomers such as styrene and α-methylstyrene; unsaturated carboxylic acid ester monomers such as methyl methacrylate; and vinyl cyanide such as acrylonitrile and methacrylonitrile. It is preferable to use a styrene copolymer obtained by copolymerizing a vinyl monomer mixture containing a monomer.

  Particularly, the vinyl monomer mixture (c) in the presence of 10 to 95 parts by weight of the copolymer (A) obtained by copolymerizing the vinyl monomer mixture (a) and the rubbery polymer (b). The rubber-containing graft copolymer (B) obtained by graft polymerization) is preferably a rubber-reinforced styrene-based transparent resin (I) comprising 90 to 5 parts by weight, wherein the vinyl monomer mixture (a) And vinyl monomer mixture (c) is aromatic vinyl monomer (a1) 5 to 70% by weight, unsaturated carboxylic acid alkyl ester monomer (a2) 30 to 95% by weight, vinyl cyanide. A monomer composition comprising 0 to 50% by weight of the monomer (a3) and another monomer (a4) copolymerizable therewith, and an unsaturated carboxylic acid monomer -Mer (excluding unsaturated carboxylic acid alkyl ester monomer (a2)) a5) is preferably substantially monomer mixture containing no to the.

  In the present invention, the acetone-soluble resin component contained in the transparent thermoplastic resin composition is an aromatic vinyl monomer (a1) 5 to 70% by weight, an unsaturated carboxylic acid alkyl ester monomer (a2). ) 30 to 95% by weight, vinyl cyanide monomer (a3) 0 to 50% by weight and other monomer copolymerizable with these (a4) 0 to 50% by weight It has been done.

  The monomer composition of the acetone-soluble resin component is aromatic vinyl monomer (a1) 5 to 70% by weight, unsaturated carboxylic acid alkyl ester monomer (a2) 30 to 95% by weight, vinyl cyanide The monomer (a3) 0 to 50% by weight and the other monomer (a4) 0 to 50% by weight copolymerizable therewith indicate that the resin composition has transparency, color tone, and impact resistance. Etc. are necessary for making the balance excellent.

  The content of the aromatic vinyl monomer (a1) in the monomer composition of the acetone-soluble resin component is in the range of 5 to 70% by weight with respect to the entire monomer composition. If it is less than 5% by weight, the resulting transparent thermoplastic resin composition is inferior in impact resistance, and if it exceeds 70% by weight, it tends to be inferior in transparency. From the viewpoint of transparency and impact resistance, it is preferably 9 to 50% by weight, particularly preferably 14 to 35% by weight.

  The amount of the unsaturated carboxylic acid alkyl ester monomer (a2) is 30 to 95% by weight based on the whole monomer composition of the acetone-soluble resin component. If it is less than 30% by weight, the transparency of the obtained transparent thermoplastic resin composition is inferior, and if it exceeds 95% by weight, the impact resistance is inferior. From the viewpoint of impact resistance and transparency, it is preferably 35 to 90% by weight, particularly preferably 40 to 85% by weight.

  The presence of the vinyl cyanide monomer (a3) is not essential, but the amount thereof is in the range of 0 to 50% by weight with respect to the whole monomer composition of the acetone-soluble resin component. If it exceeds 50% by weight, the color tone of the resin composition tends to deteriorate. From the viewpoint of color tone and impact resistance, it is preferably 0.1 to 45% by weight, particularly preferably 1 to 40% by weight.

  In addition to the aromatic vinyl monomer (a1), unsaturated carboxylic acid alkyl ester monomer (a2), and vinyl cyanide monomer (a3), the acetone-soluble resin component of the present invention includes Although not essential, the other monomer (a4) copolymerizable with can be present in the range of 0 to 50% by weight based on the whole monomer composition of the acetone-soluble resin component.

The composition of the acetone-soluble resin component of the present invention may be determined quantitatively from the following peak appearing on the FT-IR chart.
Aromatic vinyl monomer (a1): peak at 1605 cm ⁻¹ attributed to vibration of the benzene nucleus,
Unsaturated carboxylic acid alkyl ester monomer (a2): peak at 1730 cm ⁻¹ attributed to C═O stretching vibration of the carbonyl group of the ester,
-Vinyl cyanide monomer (a3): ^- A peak at 2240 cm ^-1 attributable to CN stretching.

  In the monomer composition constituting the acetone-soluble resin component in the resin composition of the present invention, the copolymer (A) and the graft component (b) of the rubber-containing graft copolymer (B) are constituted. Aromatic vinyl monomers (a1), unsaturated carboxylic acid alkyl ester monomers (a2), vinyl cyanide monomers (a3), and copolymers thereof used in preferred monomer compositions Specific examples of possible other monomers (a4) include the following compounds, respectively.

  Examples of the aromatic vinyl monomer (a1) include styrene, α-methylstyrene, p-methylstyrene, vinyltoluene, t-butylstyrene, o-ethylstyrene, o-chlorostyrene, and o, p-dichlorostyrene. Among them, styrene and α-methylstyrene are particularly preferable. These can use 1 type (s) or 2 or more types.

  Examples of the unsaturated carboxylic acid alkyl ester monomer (a2) include methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, n-butyl (meth) acrylate, (meth ) T-butyl acrylate, n-hexyl (meth) acrylate, cyclohexyl (meth) acrylate, glycidyl (meth) acrylate, hydroxyethyl (meth) acrylate, chloromethyl (meth) acrylate and (meth) acrylic Examples include 2-chloroethyl acid, and methyl methacrylate is particularly preferable. These can use 1 type (s) or 2 or more types.

  Examples of the vinyl cyanide monomer (a3) include acrylonitrile, methacrylonitrile and ethacrylonitrile, with acrylonitrile being particularly preferred. These can use 1 type (s) or 2 or more types.

  Examples of other monomers (a4) copolymerizable with these include maleimide compounds such as N-methylmaleimide, N-cyclohexylmaleimide, N-phenylmaleimide, and unsaturated amides such as acrylamide. 1 type (s) or 2 or more types can be used.

  Although there is no restriction | limiting in particular in the composition of the vinyl-type monomer mixture (a) used as the polymerization raw material of a copolymer (A), Aromatic vinyl-type monomer (a1) 5-70 weight%, unsaturated alkyl carboxylate From 30 to 95% by weight of the ester monomer (a2), 0 to 50% by weight of the vinyl cyanide monomer (a3) and 0 to 50% by weight of other monomers copolymerizable therewith (a4) From the viewpoint of impact resistance, the aromatic vinyl monomer (a1) is preferably 9 to 50% by weight, and the unsaturated carboxylic acid alkyl ester monomer (a2) 35 to 90. A monomer composition comprising 0.1% to 45% by weight of vinyl cyanide monomer (a3) and 0% to 50% by weight of other monomer copolymerizable with these (a4), Preferably, aromatic vinyl monomer (a1) 14 to 35% by weight, unsaturated 40 to 85% by weight of rubonic acid alkyl ester monomer (a2), 1 to 40% by weight of vinyl cyanide monomer (a3) and other monomers copolymerizable with these (a4) 0 to 50 It is a monomer composition consisting of% by weight.

  The vinyl-based monomer mixture (a) substantially contains an acidic monomer such as an unsaturated carboxylic acid-based monomer (excluding the unsaturated carboxylic acid alkyl ester-based monomer (a2)) (a5). It is especially preferable not to contain it in order to make the acid value of the acetone-soluble resin component in the rubber-reinforced styrene-based transparent resin composition a desired level and to improve the color tone. Here, “substantially not containing” means that these acidic monomers are not intentionally added as a monomer mixture. For example, 0.01% or more with respect to the monomer mixture (a). Addition can be considered intentional addition. The unsaturated carboxylic acid derived from impurities in each monomer of the monomer mixture (a), for example, 0.01 contained as an impurity in the unsaturated carboxylic acid alkyl ester monomer (a2). Less than% unsaturated carboxylic acids are not intentionally added. Examples of the unsaturated carboxylic acid monomer (a5) include acrylic acid and methacrylic acid.

  The rubbery polymer (b) constituting the rubbery-containing graft copolymer (B) in the present invention is not particularly limited, but examples thereof include diene rubber, acrylic rubber, and ethylene rubber. Include polybutadiene, poly (butadiene-styrene), poly (butadiene-acrylonitrile), polyisoprene, poly (butadiene-butyl acrylate), poly (butadiene-methyl acrylate), poly (butadiene-methyl methacrylate), poly (Butadiene-ethyl acrylate), ethylene-propylene rubber, ethylene-propylene-diene rubber, poly (ethylene-isobutylene), poly (ethylene-methyl acrylate), poly (ethylene-ethyl acrylate), and the like. These rubbery polymers are used in one kind or a mixture of two or more kinds. Among these, polybutadiene and styrene-butadiene copolymer rubber are particularly preferably used from the viewpoint of impact resistance improvement effect.

  The weight average particle size of the rubber polymer (b) is 0.1 to 1.5 μm from the viewpoint of impact resistance, molding processability, fluidity and appearance of the rubber-reinforced styrene resin composition (I) to be obtained. Preferably, it is in the range of 0.15 to 1.2 μm.

  The composition of the vinyl monomer mixture (c) used as a polymerization raw material for the graft component of the rubber-containing graft copolymer (B) is not particularly limited, but the transparency and impact resistance of the resulting transparent thermoplastic resin composition are not limited. Aromatic vinyl monomer (a1) 5 to 70% by weight, unsaturated carboxylic acid alkyl ester monomer (a2) 30 to 95% by weight, vinyl cyanide based on the balance of physical properties and rigidity It is preferable to contain 0 to 50% by weight of the monomer (a3) and 0 to 50% by weight of another monomer (a4) copolymerizable therewith. The monomer composition constituting the vinyl monomer mixture (c) may be the same as or different from the vinyl monomer mixture (a) constituting the copolymer (A).

  Further, in this vinyl monomer mixture (c), as in the case of the vinyl monomer mixture (a) as a polymerization raw material of the styrene copolymer, an unsaturated carboxylic acid monomer (but unsaturated) is used. The acid value of the acetone-soluble resin component in the rubber-reinforced styrene-based transparent resin composition is desired to be substantially free of acidic monomers such as (a5) except for the carboxylic acid alkyl ester monomer (a2). It is particularly preferable for achieving a level and improving the color tone. Here, “substantially not containing” is the same as in the case of the vinyl monomer mixture (a) as a polymerization raw material of the styrene copolymer.

  The intrinsic viscosity of the rubber-containing graft copolymer (B) is not particularly limited, but a range of 0.05 to 1.2 dl / g is preferable from the viewpoint of the balance between impact resistance and moldability, and further 0.1 The range of -0.7 dl / g is more preferable.

  This rubber-containing graft copolymer (B) is obtained by graft polymerization of the vinyl monomer mixture (c) in the presence of the rubber polymer (b). It is not necessary that the total amount of the mixture (c) is grafted. Usually, the mixture (c) obtained as a mixture with an ungrafted copolymer is used. This mixture is originally a composition, but in the present invention, it is collectively referred to as a rubber-containing graft copolymer (B) for convenience. The graft ratio of the rubber-containing graft copolymer (B) is not limited, but is preferably 5 to 150% by weight, more preferably 10 to 100% by weight from the viewpoint of impact resistance.

  The ratio of the rubber-like polymer (b) in the rubber-containing graft copolymer (B) is preferably 5 to 80 parts by weight, more preferably from the viewpoint of mechanical strength and moldability of the resulting resin composition. Is in the range of 20 to 70 parts by weight.

  The method of graft polymerization at the time of production of the rubber-containing graft copolymer (B) is not limited, but by any method such as a known emulsion polymerization method, suspension polymerization method, continuous bulk polymerization method, and continuous solution polymerization method. Preferably, it is produced by an emulsion polymerization method or a bulk polymerization method. Among them, in order to suppress deterioration and coloring of the rubber component due to excessive heat history, hydrolysis of the unsaturated carboxylic acid alkyl ester monomer (a2) in the melt-kneading step with the copolymer (A) is also performed. In order to control, it is most preferable to manufacture by an emulsion polymerization method from the viewpoint that it is easy to adjust the emulsifier content and the water content in the rubber-containing graft copolymer (B).

  The transparent thermoplastic resin composition of the present invention needs to contain an ultraviolet absorber (II). As the ultraviolet absorber (II), one or a mixture of two or more commonly used ultraviolet absorbers such as benzotriazole, benzophenone, and salicylate can be used. Of these, the use of a benzotriazole-based ultraviolet absorber (VII) represented by the following formula 2 is preferred.

  (In the formula, R 1 and R 2 represent an alkyl group having 1 to 25 carbon atoms or a substituted or unsubstituted phenyl group.)

  Moreover, content of ultraviolet absorber (II) is the range of 0.01-3 weight part with respect to 100 weight part of rubber reinforced styrene-type copolymers (I).

  Moreover, the transparent thermoplastic resin composition of this invention needs to contain 0.01-3 weight part of phosphorus compound (III) shown by following formula 1. If the content is less than 0.01 parts by weight, the color tone is inferior, and if it exceeds 3 parts by weight, the transparency is inferior, which is not preferable. Preferably it is 0.05-2 weight part, More preferably, it is the range of 0.1-1 weight part.

  (In the formula, R 1 and R 2 represent an alkyl group having 1 to 25 carbon atoms or a substituted or unsubstituted phenyl group.)

  Specific examples of the phosphorus compound (III) represented by the above formula 1 include bis-n-octylpentaerythritol diphosphite, bis-n-nonylpentaerythritol diphosphite, bis-n-decylpentaerythritol diphosphite. , Diphenylpentaerythritol diphosphite, bis-n-undecylpentaerythritol diphosphite, bis-n-dodecylpentaerythritol diphosphite, bis-n-octadecylpentaerythritol diphosphite, diphenylpentaerythritol diphosphite, bis ( Methylphenyl) pentaerythritol diphosphite, bis (ethylphenyl) pentaerythritol diphosphite, bis (nonylphenyl) pentaerythritol diphosphite, bis (t-butylpheny ) Having a phenyl group such as pentaerythritol diphosphite, bis (2,4-t-butylphenyl) pentaerythritol diphosphite, bis (2,6-t-butyl-4-methylphenyl) pentaerythritol diphosphite Things. In particular, in terms of color, bis (2,4-t-butylphenyl) pentaerythritol diphosphite, bis (2,6-t-butyl-4-methylphenyl) pentaerythritol diphosphite, and bis-n-octadecyl Preference is given to using pentaerythritol diphosphite. Moreover, about the addition amount, the range of 0.01-3 weight part is required with respect to 100 weight part of rubber-reinforced styrene-type copolymers (I). If the content is less than 0.01 parts by weight, the color tone of the obtained transparent thermoplastic resin composition is remarkably inferior, and if it exceeds 3 parts by weight, the transparency is remarkably inferior. Preferably it is 0.05-2 weight part, More preferably, it is the range of 0.1-1 weight part.

  The content of the ultraviolet absorber (II) and the phosphorus compound (III) is expressed by the formula 0.1 <content of the phosphorus stabilizer (III) (part by weight) / content of the ultraviolet absorber (II) (weight) Part) <2 must be satisfied. When (III) / (II) is 0.1 or less, the color tone of the thermoplastic resin composition is inferior, and when it is 2 or more, transparency is inferior, which is not preferable. Preferably, (III) / (II) is in the range of 0.1 to 1.5, more preferably 0.2 to 1.0.

  Furthermore, in the transparent thermoplastic resin composition of the present invention, the difference in refractive index between the acetone-soluble resin component and the acetone-insoluble resin component is preferably less than 0.03. It is excellent in transparency as it is less than 0.03. More preferably, it is less than 0.025, More preferably, it is less than 0.02.

  In the transparent thermoplastic resin composition of the present invention, at least one selected from a phosphorus stabilizer (IV) other than the phosphorus compound (III), a phenol stabilizer (V), and a sulfur stabilizer (VI). It is preferred to contain a seed stabilizer. By containing these stabilizers, color tone and thermal stability are further improved. As these stabilizers, commercially available ones can be used. Although there is no restriction | limiting in particular as addition amount, The range of 0.01-2 weight part is preferable with respect to 100 weight part of rubber reinforced styrene-type copolymers (I). If it is less than 0.01 part by weight, the effect is small, and if it exceeds 2 parts by weight, the transparency tends to be remarkably lowered.

  The transparent thermoplastic resin composition of the present invention includes a polyolefin such as vinyl chloride, polyethylene and polypropylene, a polyamide such as nylon 6 and nylon 66, a polyethylene terephthalate, a polybutylene terephthalate, a poly, within the range not impairing the object of the present invention. Polyester such as cyclohexanedimethyl terephthalate, polycarbonate, various elastomers and the like can be added to improve the performance as a molding resin. If necessary, various stabilizers such as sulfur-containing organic compound-based antioxidants, phenol-based, acrylate-based heat stabilizers, organic nickel-based, hindered amine-based light stabilizers, and higher fatty acid metals. Lubricants such as salts, higher fatty acid amides, plasticizers such as phthalates and phosphates, halogenated compounds such as polybromodiphenyl ether, tetrabromobisphenol-A, brominated epoxy oligomers, brominated polycarbonate oligomers, Flame retardants and flame retardant aids such as phosphorus compounds and antimony trioxide, antistatic agents, titanium oxide, other pigments and dyes can also be added. Furthermore, reinforcing agents and fillers such as glass fibers, glass flakes, glass beads, carbon fibers, and metal fibers can be added.

  With respect to the method for producing the transparent thermoplastic resin composition of the present invention, various methods such as melt kneading with a Banbury mixer, a roll, and a single-screw or multi-screw extruder can be employed.

  By using the transparent thermoplastic resin composition of the present invention for molding such as injection molding and extrusion molding, it is possible to obtain a molded product having good color tone and excellent balance of weather resistance, impact resistance and rigidity. .

  In order to describe the present invention more specifically, examples and comparative examples will be described below, but these examples do not limit the present invention. Unless otherwise specified, “%” means% by weight and “parts” means parts by weight. The measurement methods of characteristics and physical properties used in the examples are shown below.

(1) Weight average rubber particle diameter of rubber polymer Polymerized by the sodium alginate method described in “Rubber Age Vol.88 p. The particle diameter of 50% cumulative weight fraction was obtained from the weight ratio of cream and the cumulative weight fraction of sodium alginate concentration by utilizing the difference in the polybutadiene particle diameter.

(2) Graft ratio of rubber-containing graft copolymer (B) 100 ml of acetone was added to a predetermined amount (m; about 1 g) of the rubber-containing graft copolymer (B) that had been vacuum-dried at 80 ° C. for 4 hours. The solution was refluxed in a hot water bath at 70 ° C. for 3 hours, and the solution was centrifuged at 8800 rpm (10000 G) for 40 minutes. The insoluble matter was filtered, and the insoluble matter was vacuum-dried at 80 ° C. for 4 hours. (N) was measured. The graft ratio was calculated from the following formula. Here, L is the rubber content of the graft copolymer.
Graft rate (%) = {[(n) − (m) × L] / [(m) × L]} × 100.

(3) Reduced viscosity ηsp / c of acetone-soluble resin component
The measurement sample was dissolved in methyl ethyl ketone, and the reduced viscosity ηsp / c was measured at 30 ° C. using a Ubbelohde viscometer as a 0.4 g / 100 ml methyl ethyl ketone solution.

(4) Monomer composition of acetone-soluble resin component 100 ml of acetone was added to 1 g of a resin composition sample and refluxed in a 70 ° C. water bath for 3 hours, and this solution was centrifuged at 8800 rpm (10000 G) for 40 minutes. Then, insoluble matter was filtered. The filtrate was concentrated with a rotary evaporator, and a film with a thickness of 30 ± 5 μm was prepared by using a heated press set at 220 ° C. using a precipitate dried in vacuo at 80 ° C. for 4 hours (acetone-soluble resin component). The monomer composition was determined from the area of each peak appearing on the chart obtained by analyzing this film as a sample by FT-IR. The correspondence between each monomer and peak is as follows.
Methyl methacrylate monomer unit: peak at 3460 cm ⁻¹ which is a harmonic overtone peak at 1730 cm ⁻¹ attributed to C═O stretching vibration of the carbonyl group of the ester,
Methacrylic acid monomer unit: peak at 1690 cm ⁻¹ attributed to C═O stretching vibration of carbonyl group of carboxylic acid,
Styrene monomer unit: peak of 1605 cm ⁻¹ attributed to vibration of benzene nucleus,
Acrylonitrile monomer unit: A peak at 2240 cm ⁻¹ attributed to CN stretching.

(5) Refractive index To 1 g of the thermoplastic resin composition, 200 ml of acetone was added and refluxed in a 70 ° C. hot water bath for 3 hours. p. m. After centrifuging at (10000 G) for 40 minutes, the insoluble matter was filtered. The filtrate was concentrated with a rotary evaporator to obtain a precipitate (acetone soluble matter). Each sample was dried under reduced pressure at 60 ° C. for 5 hours to form a film sample. A small amount of 1-bromonaphthalene was dropped into this measurement sample, and the refractive index was measured using an Abbe refractometer under the following conditions.
Light source: Sodium lamp D line Measurement temperature: 20 ° C.

(6) Izod Impact Strength of Resin Composition Measured by ASTM D256 (23 ° C., with V notch).

(7) Tensile strength of resin composition Measured according to ASTM 638.

(8) Color tone Using an injection molded product having a thickness of 2.5 mm, X, Y and Z values were measured using a color computer manufactured by Dainichi Seika Co., Ltd., and the YI value was calculated from the following formula.
YI value = 100 × (1.28X−1.06Z) / Y.

(9) Transparency evaluation method (haze value)
Using a direct reading haze meter manufactured by Toyo Seiki Co., Ltd., the haze value [%] of a 2.5 mm thick square plate was measured. The lower the haze value, the better the resin.

(10) Weather resistance After irradiating under the conditions of a black panel temperature of 63 ° C./no rain / 300 h using a sunshine weatherometer manufactured by Suga Test Instruments Co., Ltd., X using a color computer manufactured by Dainichi Seika Co., Ltd. Y and Z values were measured to determine ΔE * before and after irradiation.

[Reference Example 1] Production of copolymer (A) by copolymerizing vinyl monomer mixture (a) (1) Production of vinyl copolymer (A-1) Baffle with a capacity of 20 liters And 0.05 part of a methyl acrylate / acrylamide copolymer produced by the method described in Example 1 of Japanese Patent Publication No. 45-24151 was dissolved in 165 parts of ion-exchanged water in a stainless steel autoclave equipped with a Foudra type stirring blade. The solution was added and stirred at 400 rpm, and the system was replaced with nitrogen gas. Next, the following mixed substances were added while stirring the reaction system, and the temperature was raised to 60 ° C. to initiate polymerization.
Methyl methacrylate 70 parts Styrene 25 parts Acrylonitrile 5 parts t-Dodecyl mercaptan 0.05 part 2,2'-azobisisobutyronitrile 0.4 part Deionized water 150 parts.

  That is, after raising the reaction temperature to 65 ° C. over 15 minutes, the temperature was raised to 100 ° C. over 50 minutes. Thereafter, the reaction system was cooled, the polymer was separated, washed, and dried according to the usual method to obtain a vinyl copolymer (A-1). The reduced viscosity ηsp / c of this vinyl copolymer (A-1) was 0.33 dl / g.

(2) Production of vinyl copolymer (A-2) A vinyl copolymer (A-) was produced in the same manner as A-1, except that the monomer composition of methyl methacrylate, styrene, and acrylonitrile was changed as follows. 2) was obtained. The reduced viscosity ηsp / c of this vinyl copolymer (A-2) was 0.34 dl / g.
Methyl methacrylate 20 parts Styrene 75 parts Acrylonitrile 5 parts.

[Reference Example 2] Production of rubber-containing graft copolymer (B) (1) Production of graft copolymer (B-1) 50 parts of polybutadiene latex (rubber particle diameter 0.3 μm, gel content 85%) (In terms of solid content), 180 parts of pure water, 0.4 part of sodium formaldehyde sulfoxylate, 0.1 part of sodium ethylenediaminetetraacetate, 0.01 part of ferrous sulfate and 0.1 part of sodium phosphate are charged into a reaction vessel. After nitrogen substitution, the temperature was adjusted to 65 ° C., and a mixture of 11.5 parts of styrene, 4.0 parts of acrylonitrile, 34.5 parts of methyl methacrylate and 0.3 part of n-dodecyl mercaptan was continuously added over 4 hours with stirring. It was dripped. At the same time, a mixture of 0.25 parts cumene hydroperoxide, 2.5 parts sodium oleate as an emulsifier and 25 parts pure water was continuously added dropwise over 5 hours, and after completion of the addition, the mixture was further maintained for 1 hour for polymerization. Ended.

  The latex product obtained after completion of polymerization was coagulated by pouring into 2000 parts of 95 ° C. water to which 1.0 part of sulfuric acid was added, and then neutralized with 0.8 part of sodium hydroxide. Thus, a coagulated slurry was obtained. This was centrifuged, washed in 2000 parts of water at 40 ° C. for 5 minutes, centrifuged, and dried in a hot air dryer at 60 ° C. for 12 hours to obtain a powdery graft copolymer (B-1). Prepared. Table 2 shows the graft characteristics and graft components of the obtained graft copolymer (B-1).

[Examples 1 to 11 and Comparative Examples 1 to 4]
Rubber reinforced thermoplastic resin (I) prepared in Reference Examples 1 and 2, the following ultraviolet absorber (II), phosphorus compound (III) <other phosphorus stabilizer (IV), phenol stabilizer (V), And a sulfur-based stabilizer (VI) in a mixing ratio shown in Table 3, and using a vented 30 mmφ twin-screw extruder (Ikegai Iron Works, PCM-30), melting and kneading and extruding the pellets A molded resin composition was produced.

UV absorber (II)
Ultraviolet absorber (II-1): Biosorb 520 (manufactured by Kyodo Pharmaceutical Co., Ltd.)
Ultraviolet absorber (II-2): Seasorb 709 (manufactured by Cii Kasei Co., Ltd.).

Phosphorus compound (III)
Phosphorus compound (III-1): bis (2,4-t-butylphenyl) pentaerythritol diphosphite (Asahi Denka Kogyo PEP24G)
Phosphorus compound (III-2): bis (2,6-t-butyl-4-methylphenyl) pentaerythritol diphosphite (Asahi Denka Kogyo PEP36)
Phosphorus compound (III-3): Bis-n-octadecylpentaerythritol diphosphite (PEP8 manufactured by Asahi Denka Kogyo Co., Ltd.).

  Other phosphorus stabilizer (IV): Tris (2,4-t-butylphenyl) phosphite (2112 manufactured by Asahi Denka Kogyo Co., Ltd.).

Phenolic stabilizer (V)
Phenol stabilizer (V-1): AO50F manufactured by Asahi Denka Kogyo Co., Ltd.
Phenol stabilizer (V-2): “Yoshinox” 425 manufactured by Yoshitomi Pharmaceutical Co., Ltd.

 Sulfur-based stabilizer (VI): DMTP manufactured by Yoshitomi Pharmaceutical.

  Subsequently, each test piece was shape | molded on the conditions which made the injection pressure into the minimum pressure + 1MPa with the injection molding machine (the Sumitomo Heavy Industries make, Promat 40/25), and measured the physical property. The results are shown in Table 4.

  The rubber-reinforced styrene-based transparent resin compositions of the present invention in Examples 1 to 9 were excellent in terms of weather resistance, transparency, color tone, impact resistance and rigidity, with a good balance of physical properties. However, the resin composition obtained in Comparative Example 1 is inferior in weather resistance because the ultraviolet absorber was outside the range specified in the present invention. Comparative Examples 2, 3, 5, and 6 are inferior in color tone. Moreover, since the comparative example 4 is outside the range which the phosphorus stabilizer specified by this invention, transparency is inferior.

  Since the transparent thermoplastic resin composition and molded product of the present invention have good color tone and excellent balance of weather resistance, impact resistance and rigidity, such as OA equipment, home appliances, general goods, toys and building materials, etc. Can be widely applied in the field.

Claims (6)

A resin composition containing a rubber-reinforced styrene copolymer (I) reinforced with a rubbery polymer, wherein the difference in refractive index between the acetone-soluble resin component and the acetone-insoluble resin component is less than 0.03, and The acetone-soluble resin component contained in the resin composition is an aromatic vinyl monomer (a1) 5 to 70% by weight, an unsaturated carboxylic acid alkyl ester monomer (a2) 30 to 95% by weight, It is produced from a monomer composition consisting of 0 to 50% by weight of vinyl cyanide monomer (a3) and another monomer (a4) copolymerizable with these, The ultraviolet absorber (II) is 0.01 to 3 parts by weight and the phosphorus compound (III) represented by the following formula 1 is 0.01 to 3 parts by weight with respect to 100 parts by weight of the rubber-reinforced styrene copolymer (I). Part of these UV absorbers (II And phosphorous compound (III) content satisfying formula 0.1 <phosphorus stabilizer (III) content (parts by weight) / ultraviolet absorber (II) content (parts by weight) <2. Thermoplastic resin composition.

(In the formula, R 1 and R 2 represent an alkyl group having 1 to 25 carbon atoms or a substituted or unsubstituted phenyl group.) Furthermore, it contains at least one stabilizer selected from a phosphorus stabilizer (IV), a phenol stabilizer (V) and a sulfur stabilizer (VI) other than the phosphorus compound (III). Transparent thermoplastic resin composition. Presence of 10 to 95 parts by weight of a copolymer (A) obtained by copolymerizing the vinyl monomer mixture (a) with the rubber-reinforced styrene copolymer (I) and a rubbery polymer (b) The transparent thermoplastic resin composition according to claim 1 or 2, comprising 90 to 5 parts by weight of a rubber-containing graft copolymer (B) formed by graft polymerization of a vinyl monomer mixture (c). The vinyl-based monomer mixture (a) and the vinyl-based monomer mixture (c), which are raw materials for the rubber-reinforced styrene-based copolymer (I), are aromatic vinyl-based monomers (a1) of 5 to 70 weights. %, Unsaturated carboxylic acid alkyl ester monomer (a2) 30 to 95% by weight, vinyl cyanide monomer (a3) 0 to 50% by weight and other monomers copolymerizable therewith (a4) ) Having a monomer composition consisting of 0 to 50% by weight, and substantially comprising an unsaturated carboxylic acid monomer (excluding the unsaturated carboxylic acid alkyl ester monomer (a2)) (a5) The transparent thermoplastic resin composition according to claim 3, which is a monomer mixture not containing. The transparent thermoplastic resin composition according to any one of claims 1 to 4, wherein the ultraviolet absorber (II) is a compound (VII) represented by the following formula 2.

(In the formula, R 1 and R 2 represent an alkyl group having 1 to 25 carbon atoms or a substituted or unsubstituted phenyl group.) The molded article manufactured from the transparent thermoplastic resin composition of any one of Claims 1-6.