JP7045994B2 - Methacrylic resin composition and its manufacturing method, molded body, film, laminated film, laminated molded body - Google Patents

Description

The present invention relates to a methacrylic resin composition, a method for producing the same, a molded body, a film, a laminated film, and a laminated molded body.

The methacrylic resin has high transparency and is suitable as a material for optical members, lighting members, signboard members, decorative members and the like. However, since the general-purpose methacrylic resin has a low glass transition temperature (Tg) of about 110 ° C. and poor heat resistance, the dimensional stability of the molded product with respect to heat is not good. As a methacrylic resin having a high Tg, a methacrylic resin having a high syndiotacticity (rr) is known. Examples of the method for producing a methacrylic resin having a high syndiotacticity (rr) include an anion polymerization method (see Patent Documents 1 and 2). However, the methacrylic resin having high syndiotacticity (rr) obtained by this method has poor moldability, and the obtained molded product tends to be inferior in surface smoothness and the like. Although the moldability can be improved by lowering the molecular weight, the mechanical strength of the obtained molded product tends to decrease. Therefore, at present, a molded product made of a methacrylic resin having a high syndiotacticity (rr) has not been put into practical use.

In Patent Document 3, a methacrylic resin [1] having a triplet-labeled syndiotacticity (rr) of 65% or more and a triplet-labeled syndiotacticity (rr) of 45 to 58%. A methacrylic resin composition containing a methacrylic resin [2] in a mass ratio of 40/60 to 70/30 of the methacrylic resin [1] / methacrylic resin [2] is disclosed (claim 1). By blending the methacrylic resin [1] having a high syndiotacticity (rr) and the atactic methacrylic resin [2] in the above mass ratio, it is possible to achieve both improvement in heat resistance and good moldability.

Japanese Unexamined Patent Publication No. 3-263421 Japanese Unexamined Patent Publication No. 2002-327012 International Publication No. 2014/185509

As described above, in general, in methacrylic resin, heat resistance (dimensional stability against heat) and moldability are contradictory characteristics, and it is difficult to achieve both of them. Further, in recent years, there have been increasing demands for molded products such as complicated shapes and high dimensional stability against heat. Therefore, it has been required to be able to mold a molded product having good moldability at high temperature and high dimensional stability with respect to heat.

The present invention has been made in view of the above problems, and a methacrylic resin composition capable of obtaining a molded product having good high-temperature moldability and high dimensional stability with respect to heat and a method for producing the same. The purpose is to provide.

The present invention provides the following methacrylic resin composition, a method for producing the same, a molded product, a film, a laminated film, and a laminated molded product.
[1] Acrylic resin (M1) having an α relaxation temperature T _α1 of 137 ° C. or higher when measured dynamically viscoelasticity in a tensile mode at 1 Hz.
A methacrylic resin composition with a methacrylic resin (M2) having an α relaxation temperature T _α2 of 132 ° C. or lower when measured in a tensile mode at 1 Hz for dynamic viscoelasticity.
When the melt viscosities of the methacrylic resin (M1) and the methacrylic resin (M2) at 260 ° C. and a shear rate of 122 sec ^-1 are η ₁ and η ₂ , respectively, η ₁ > η ₂ .
A methacrylic resin composition having a mass ratio of methacrylic resin (M1) / methacrylic resin (M2) of 2/98 to 29/71.

[2] The methacrylic resin composition according to [1], wherein the methacrylic resin (M1) has a molecular weight distribution (Mw / Mn) of 1.0 to 1.4.
[3] The methacrylic resin composition of [1] or [2], wherein the methacrylic resin (M1) has a weight average molecular weight (Mw) of 40,000 to 200,000.
[4] The methacrylic resin composition according to any one of [1] to [3], wherein the content of the methyl methacrylate monomer unit of the methacrylic resin (M2) is 99% by mass or more.
[5] The methacrylic resin composition according to any one of [1] to [4], further comprising a polycarbonate resin (PC) and / or a phenoxy resin (PR).
[6] The methacrylic resin composition according to any one of [1] to [5], further comprising a crosslinked rubber (CR) and / or a block copolymer (BP).
[7] The methacrylic resin composition according to any one of [1] to [6], further comprising an ultraviolet absorber (LA).

[8] When the melt viscosities of the methacrylic resin (M1) and the methacrylic resin (M2) at 260 ° C. and a shear rate of 122 sec ^-1 are η ₁ and η ₂ , η ₁ > η ₂ .
Acrylic resin (M1) having an α relaxation temperature T _α1 of 137 ° C or higher when measured dynamically viscoelasticity in a tensile mode at 1 Hz.
Acrylic resin (M2) having an α relaxation temperature T _α2 of 132 ° C or lower when measured dynamically viscoelasticity in a tensile mode at 1 Hz.
A method for producing a methacrylic resin composition, which is melt-kneaded at a mass ratio of methacrylic resin (M1) / methacrylic resin (M2) of 2/98 to 29/71.

[9] A molded product made of the methacrylic resin composition according to any one of [1] to [7].
[10] A film comprising the methacrylic resin composition according to any one of [1] to [7].
[11] The film of [10] which is a stretched film.
[12] A laminated film having a layer composed of the film of [10] or [11].
[13] The laminated film of [12] further having a layer composed of a metal and / or a metal oxide.
[14] The laminated film of [12] or [13] further having an adhesive layer.
[15] A laminated molded product in which the laminated film according to any one of [12] to [14] is laminated on a base material.

In the present specification, "α relaxation temperature (T _α )", "melt viscosity (η)", "weight average molecular weight (Mw)", and "molecular weight distribution (Mw / Mn)" are referred to as "Examples". It shall be measured by the method described in.

INDUSTRIAL APPLICABILITY According to the present invention, it is possible to provide a methacrylic resin composition capable of obtaining a molded product having good high-temperature moldability and high dimensional stability with respect to heat, and a method for producing the same.

"Methyl resin composition"
The methacrylic resin composition of the present invention comprises a methacrylic resin (M1) having an α relaxation temperature T _α1 of 137 ° C. or higher when measured in a tensile mode at 1 Hz and a dynamic viscoelasticity measurement in a tensile mode at 1 Hz. It contains a methacrylic resin (M2) having an α relaxation temperature T _α2 of 132 ° C. or lower.

As used herein, the “α relaxation temperature (T _α )” is the temperature at the peak of relaxation (α relaxation) caused by the segment motion of the polymer backbone. The α relaxation temperature (T _α ) can be measured by the method described in the section of [Example].
In general, a correlation is observed between the glass transition temperature (Tg) and the α relaxation temperature (T _α ) obtained from the DSC curve, but in the present invention, the α relaxation temperature (T _α ) is used instead. Tg is not used as an index.

(Methacrylic resin (M1))
The methacrylic resin (M1) is not particularly limited as long as the α relaxation temperature T _α1 when dynamic viscoelasticity is measured in a tensile mode and a sine wave of 1 Hz is 137 ° C. or higher. One type or two or more types of methacrylic resin (M1) can be used. The methacrylic resin (M1) contains one or more methacrylic ester monomer units such as a methyl methacrylate (MMA) monomer unit. Examples of the methacrylic acid ester include methacrylic acid alkyl esters such as MMA, ethyl methacrylate, and butyl methacrylate; methacrylic acid aryl esters such as phenyl methacrylate; cycloalkyl esters of methacrylic acid such as cyclohexyl methacrylate and norbornenyl methacrylate. Can be mentioned. Of these, methacrylic acid alkyl esters are preferred, and MMA is most preferred.

The content of the methacrylic acid ester monomer unit in the methacrylic resin (M1) is preferably 20% by mass or more, more preferably 50% by mass or more. The main chain of the methacrylic resin (M1) is a methacrylic copolymer (A1) containing an MMA monomer unit and a monomer unit that raises the α relaxation temperature (T _α ), an MMA monomer unit, and a ring structure. Examples thereof include a methacrylic copolymer (A2) containing the structural unit having the same structure, and a methacrylic resin (A3) having a high syndiotacticity (rr) of triplet display.

<Methacrylic copolymer (A1)>
As the monomer unit for increasing the α relaxation temperature (T _α ) in the methacrylic acid copolymer (A1), 2-isobornyl methacrylate and 8-tricyclo methacrylate [5.2.1.0 ^2,6 ] decanyl are used. , 2-Norbornyl Methacrylate, and methacrylic acid cycloalkyl esters such as 2-adamantyl Methacrylic Acid; (meth) acrylic acids such as acrylic acid and methacrylic acid; acrylamide, methacrylamide, N-methylmethacrylamide, and N, N- Examples thereof include structural units derived from monomers such as (meth) acrylamides such as dimethylmethacrylamide.

<Methacrylic copolymer (A2)>
Examples of the structural unit having a ring structure in the main chain of the methacrylic copolymer (A2) include a lactone ring unit, a maleic anhydride unit, a glutaric anhydride unit, a glutaricimide unit, and an N-substituted maleimide unit. Alternatively, structural units containing tetrahydropyran ring units are preferred. As a method for producing the methacrylic copolymer (A2), a method of copolymerizing a cyclic monomer having a polymerizable unsaturated carbon-carbon double bond such as maleic anhydride and N-substituted maleimide with MMA or the like; polymerization Examples thereof include a method of intramolecularly cyclizing a part of the molecular chain of the methacrylic resin obtained by the above method.

The content of the MMA monomer unit of the methacrylic copolymer (A2) is preferably 20 to 99% by mass, more preferably 30 to 95% by mass, and particularly preferably 40 to 90% by mass, and mainly has a ring structure. The content of the structural unit contained in the chain is preferably 1 to 80% by mass, more preferably 5 to 70% by mass, and particularly preferably 10 to 60% by mass. The content of the MMA monomer unit in the methacrylic copolymer (A2) includes the MMA monomer unit converted into a structural unit having a ring structure in the main chain by intramolecular cyclization. Not included.

As a structural unit having a ring structure in the main chain, a structural unit containing a> CH—OC (= O) -group in the ring structure and a —C (= O) -OC (= O) -group as a ring. Structural units included in the structure, -C (= O) -NC (= O) -groups in the ring structure, or> CH-O-CH <groups in the ring structure are preferred.

> CH-OC (= O) -Structural units containing a group in the ring structure include β-propiolactone diyl (also known as oxooxetandyl) structural unit and γ-butyrolactone diyl (also known as 2-oxodihydrofurangue). Il) structural units, and lactone-diyl structural units such as δ-valerolactone diyl (also known as 2-oxodihydropyrandiyl) structural units. In addition, "> C" in the formula means that the carbon atom C has two bonds.

Examples of the δ-valerolactone diyl structural unit include structural units represented by the following formula (I).

In formula (I), R ¹⁴ and R ¹⁵ are each independently a hydrogen atom or an organic residue having 1 to 20 carbon atoms, and it is preferable that R ¹⁴ is a hydrogen atom and R ¹⁵ is a methyl group. R ¹⁶ is −COOR, and R is a hydrogen atom or an organic residue having 1 to 20 carbon atoms, preferably a methyl group. "*" Means a bond.
Examples of the organic residue include a linear or branched alkyl group, a linear or branched alkylene group, an aryl group, an -OAc group, a -CN group and the like. The organic residue may contain an oxygen atom. "Ac" indicates an acetyl group. The carbon number of the organic residue is preferably 1 to 10, more preferably 1 to 5.
The δ-valerolactone diyl structural unit can be contained in the methacrylic resin by intramolecular cyclization of two MMA monomer units adjacent to each other.

The structural unit containing the -C (= O) -OC (= O) -group in the ring structure includes a 2,5-dioxodihydrofrangyl structural unit, a 2,6-dioxodihydropyrandiyl structural unit, and the like. And 2,7-dioxooxepangyl structural units and the like.

Examples of the 2,5-dioxodihydrofrangyl structural unit include structural units represented by the following formula (II).

In formula (II), R ²¹ and R ²² are independent hydrogen atoms or organic residues having 1 to 20 carbon atoms, respectively. "*" Means a bond.
Examples of the organic residue include a linear or branched alkyl group, a linear or branched alkylene group, an aryl group, an -OAc group, a -CN group and the like. The organic residue may contain an oxygen atom. "Ac" indicates an acetyl group. The carbon number of the organic residue is preferably 1 to 10, more preferably 1 to 5.
It is preferable that both R ²¹ and R ²² are hydrogen atoms. In that case, it is preferable that styrene or the like is copolymerized from the viewpoint of ease of production, adjustment of natural birefringence, and the like. Specific examples thereof include the copolymer having a styrene monomer unit, an MMA monomer unit, and a maleic anhydride monomer unit described in International Publication No. 2014/021264.
The 2,5-dioxodihydrofrangyl structural unit can be contained in the methacrylic resin by copolymerization with maleic anhydride or the like.

Examples of the 2,6-dioxodihydropyrandiyl structural unit include structural units represented by the following formula (III).

In formula (III), R ³³ and R ³⁴ are independent hydrogen atoms or organic residues having 1 to 20 carbon atoms, respectively. "*" Means a bond.
Examples of the organic residue include a linear or branched alkyl group, a linear or branched alkylene group, an aryl group, an -OAc group, a -CN group and the like. The organic residue may contain an oxygen atom. "Ac" indicates an acetyl group. The organic residue preferably has 1 to 10 carbon atoms, more preferably 1 to 5 carbon atoms, and particularly preferably a methyl group.
The 2,6-dioxodihydropyrandiyl structural unit can be contained in the methacrylic resin by intramolecular cyclization of two MMA monomers adjacent to each other.

The structural unit containing the -C (= O) -NC (= O) -group in the ring structure (note that the other bond possessed by N is omitted) is 2,5-dioxopyrrolidine. Examples thereof include a diyl structural unit, a 2,6-dioxopiperidine diyl structural unit, and a 2,7-dioxoazepandiyl structural unit.

Examples of the 2,6-dioxopiperidinediyl structural unit include structural units represented by the following formula (IV).

In formula (IV), R ⁴¹ and R ⁴² are each independently a hydrogen atom or an alkyl group having 1 to 8 carbon atoms, and R ⁴³ is a hydrogen atom, an alkyl group having 1 to 18 carbon atoms, and 3 to 12 carbon atoms. It is a cycloalkyl group or an aryl group having 6 to 10 carbon atoms. "*" Means a bond.
From the viewpoint of easy availability of raw materials, cost, heat resistance, etc., it is preferable that R ⁴¹ and R ⁴² are independently hydrogen atoms or methyl groups, respectively, where R ⁴¹ is a methyl group and R ⁴² is a hydrogen atom. Is more preferable. R ⁴³ is preferably a hydrogen atom, a methyl group, an n-butyl group, a cyclohexyl group, or a benzyl group, and more preferably a methyl group.

Examples of the 2,5-dioxopyrrolidinediyl structural unit include structural units represented by the following formula (V).

In formula (V), R ⁵² and R ⁵³ are independently hydrogen atoms, alkyl groups having 1 to 12 carbon atoms, or alkyl groups having 6 to 14 carbon atoms, respectively. R ⁵¹ is an arylalkyl group having 7 to 14 carbon atoms, or an aryl group having an unsubstituted or substituent and having 6 to 14 carbon atoms. The substituent referred to here is a halogeno group, a hydroxyl group, a nitro group, an alkoxy group having 1 to 12 carbon atoms, an alkyl group having 1 to 12 carbon atoms, or an arylalkyl group having 7 to 14 carbon atoms. "*" Means a bond. R ⁵¹ is preferably a phenyl group or a cyclohexyl group, and both R ⁵² and R ⁵³ are preferably hydrogen atoms.
The 2,5-dioxopyrrolidinediyl structural unit can be contained in the methacrylic resin by copolymerization using N-substituted maleimide or the like.

> CH—O—CH <Structural unit containing a group in the ring structure includes an oxetane diyl structural unit, a tetrahydrofuran diyl structural unit, a tetrahydropyran diyl structural unit, an oxepan diyl structural unit, and the like. In addition, "> C" in the formula means that the carbon atom C has two bonds.

Examples of the tetrahydropyrandiyl structural unit include structural units represented by the following formula (VI).

In formula (VI), R ⁶¹ and R ⁶² are independently hydrogen atoms, linear or branched hydrocarbon groups having 1 to 20 carbon atoms, or hydrocarbon groups having a ring structure and having 3 to 20 carbon atoms, respectively. Is. "*" Means a bond. R ⁶¹ and R ⁶² are independently tricyclo [5.2.1.0 ^2,6 ] decanyl group, 1,7,7-trimethylbicyclo [2.2.1] heptane-3-yl group, t. -Butyl group and 4-t-butylcyclohexanyl group are preferable.

Among the structural units having the above ring structure in the main chain, the δ-valerolactone diyl structural unit and the 2,5-dioxodihydrofrangyl structural unit are preferable from the viewpoint of raw materials and ease of manufacture.

The molecular weight distribution of the methacrylic copolymers (A1) and (A2) (ratio of weight average molecular weight (Mw) to number average molecular weight (Mn), Mw / Mn) is preferably 1.2 to 5.0, more preferably. Is 1.3 to 3.5. The lower the Mw / Mn, the better the impact resistance and toughness of the obtained molded product. The higher the Mw / Mn, the higher the melt fluidity of the methacrylic resin composition, and the better the surface smoothness of the obtained molded product tends to be.
In the present specification, Mw and Mn are values obtained by converting chromatograms measured by gel permeation chromatography (GPC) into molecular weights of standard polystyrene. Mw and Mw / Mn can be measured by the method described in the [Examples] section.

The glass transition temperature (Tg) of the methacrylic copolymer (A2) is preferably 120 ° C. or higher, more preferably 123 ° C. or higher, and particularly preferably 124 ° C. or higher. The upper limit of Tg of the methacrylic copolymer (A2) is preferably 160 ° C.
In the present specification, the glass transition temperature (Tg) shall be measured at a temperature of room temperature or higher in accordance with JIS K7121. The first temperature rise (1st run) was performed at a temperature rise rate of 10 ° C./min to 230 ° C., and after cooling to room temperature, the temperature was raised from room temperature to 230 ° C. for the second time at a temperature rise rate of 10 ° C./min. (2nd run) is carried out. The midpoint glass transition temperature of the 2nd run is determined as Tg.

<Metal resin (A3)>
The methacrylic resin (A3) has a syndiotacticity (rr) of 65% or more, preferably 70 to 90%, and more preferably 72 to 85% in triplet display. When the syndiotacticity (rr) is 65% or more, the α relaxation temperature (T _α ) is significantly increased, and the surface hardness of the obtained molded product is significantly increased.
The molecular weight distribution (Mw / Mn) of the methacrylic resin (A3) is preferably 1.0 to 1.8, more preferably 1.0 to 1.4, and particularly preferably 1.03 to 1.3. When a methacrylic resin (A3) having a molecular weight distribution (Mw / Mn) within such a range is used, the obtained methacrylic resin composition has excellent mechanical strength. Mw and Mw / Mn can be controlled by adjusting the type and / or amount of the polymerization initiator used in the production.

The methacrylic resin (M1) may contain one or more other monomer units other than the above-mentioned monomer units listed in the methacrylic copolymers (A1), (A2) and the methacrylic resin (A3). good. Other monomer units include acrylic acid alkyl esters such as methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, and 2-ethylhexyl acrylate; acrylic acid aryl esters such as phenyl acrylate; Acrylic acid cycloalkyl esters such as cyclohexyl acrylate and norbornenyl acrylate; aromatic vinyl compounds such as styrene and α-methylstyrene; nitriles such as acrylonitrile and methacrylonitrile, etc., polymerizable carbon in one molecule -A structural unit derived from a vinyl-based monomer having only one carbon double bond can be mentioned.

The Mw of the methacrylic resin (M1) is preferably 40,000 to 200,000, more preferably 40,000 to 150,000, and particularly preferably 50,000 to 120,000. When Mw is 40,000 or more, the mechanical strength (impact resistance, toughness, etc.) of the obtained molded product tends to be improved, and when it is 200,000 or less, the fluidity of the methacrylic resin composition is improved and the moldability is improved. Tends to improve.
The melt flow rate (MFR) measured under the conditions of 230 ° C. and a 3.8 kg load of the methacrylic resin (M1) is preferably 0.1 g / 10 minutes or more, more preferably 0.2 to 30 g / 10 minutes, particularly. It is preferably 0.5 to 20 g / 10 minutes, and most preferably 1.0 to 15 g / 10 minutes.

The methacrylic resin (M1) can be produced by a known polymerization method of a radical polymerization method and an anion polymerization method. The radical polymerization method should be selected from a polymerization method such as a bulk polymerization method, a solution polymerization method, a suspension polymerization method, and an emulsion polymerization method, and the anion polymerization method should be selected from a polymerization method such as a bulk polymerization method and a solution polymerization method. Can be done.
The radical polymerization method can be carried out without a solvent or in a solvent, and it is preferable to carry out the radical polymerization method without a solvent because a methacrylic resin (M1) having a low impurity concentration can be obtained. From the viewpoint of silvering or suppressing coloring of the molded product, it is preferable to carry out the polymerization reaction in an atmosphere of an inert gas such as nitrogen gas with a low dissolved oxygen content.

Examples of the polymerization initiator used in the radical polymerization method include t-hexylperoxyisopropyl monocarbonate, t-hexylperoxy2-ethylhexanoate, and 1,1,3,3-tetramethylbutylperoxy2-ethylhexanoate. Noate, t-butylperoxypivalate, t-hexylperoxypivalate, t-butylperoxyneodecanoate, t-hexylperoxyneodecanoate, 1,1,3,3-tetra Methylbutylperoxyneodecanoate, 1,1-bis (t-hexylperoxy) cyclohexane, benzoyl peroxide, 3,5,5-trimethylhexanoyl peroxide, lauroyl peroxide, 2,2'-azobis ( 2-Methylpropionitrile), 2,2'-azobis (2-methylbutyronitrile), dimethyl 2,2'-azobis (2-methylpropionate) and the like. Of these, t-hexylperoxy 2-ethylhexanoate, 1,1-bis (t-hexylperoxy) cyclohexane, and dimethyl 2,2'-azobis (2-methylpropionate) are preferred. One kind or two or more kinds of polymerization initiators can be used.

The 1-hour half-life temperature of the polymerization initiator is preferably 60 to 140 ° C, more preferably 80 to 120 ° C. The polymerization initiator has a hydrogen extraction ability of preferably 20% or less, more preferably 10% or less, and particularly preferably 5% or less. The amount of the polymerization initiator used is preferably 0.0001 to 0.02 parts by mass, more preferably 0.001 to 0.01, based on 100 parts by mass of one or more types of monomers subjected to the polymerization reaction. It is by mass, particularly preferably 0.005 to 0.007 parts by mass.

The hydrogen extraction capacity can be known from the technical data of the polymerization initiator manufacturer (for example, the technical data of Nippon Oil & Fat Co., Ltd. "Hydrogen extraction capacity and initiator efficiency of organic peroxides" (created in April 2003)). Can be done. Further, it can be measured by a radical trapping method using an α-methylstyrene dimer (α-methylstyrene dimer trapping method). This measurement is generally performed as follows. First, the polymerization initiator is cleaved in the coexistence of α-methylstyrene dimer as a radical trapping agent to generate a radical fragment. Among the generated radical fragments, the radical fragment having a low hydrogen extraction ability is added to and captured by the double bond of α-methylstyrene dimer. On the other hand, a radical fragment having a high hydrogen abstraction ability abstracts hydrogen from cyclohexane to generate a cyclohexyl radical, and this cyclohexyl radical is added to and trapped in the double bond of α-methylstyrene dimer to generate a cyclohexane trapping product. Therefore, the ratio (molar fraction) of radical fragments having high hydrogen extraction ability to the theoretical amount of radical fragment generation, which is obtained by quantifying cyclohexane or cyclohexane capture product, is determined as hydrogen extraction ability.

Chain transfer agents used in the radical polymerization method include n-octyl mercaptan, n-dodecyl mercaptan, t-dodecyl mercaptan, 1,4-butanedithiol, 1,6-hexanedithiol, ethylene glycol bisthiopropionate, butane. Didiol bisthioglycolate, butanediol bisthiopropionate, hexanediol bisthioglycolate, hexanediol bisthiopropionate, trimetylolpropanthris- (β-thiopropionate), and pentaerythritol tetrakisthiopropio. Examples thereof include alkyl mercaptans such as nate. Of these, monofunctional alkyl mercaptans such as n-octyl mercaptan and n-dodecyl mercaptan are preferable. The chain transfer agent may be used alone or in combination of two or more.

From the viewpoint of the moldability of the resin and the mechanical strength of the molded product, the amount of the chain transfer agent used is preferably 0.01 to 1 mass by mass with respect to 100 parts by mass of one or more types of monomers subjected to the polymerization reaction. Parts, more preferably 0.05 to 0.8 parts by mass, particularly preferably 0.1 to 0.6 parts by mass, and most preferably 0.10 to 0.5 parts by mass. The amount of the chain transfer agent used is preferably 2500 to 10000 parts by mass, more preferably 3000 to 9000 parts by mass, and particularly preferably 3500 to 6000 parts by mass with respect to 100 parts by mass of the polymerization initiator.

As the solvent used in the radical polymerization method, aromatic hydrocarbons such as benzene, toluene, and ethylbenzene are preferable. One kind or two or more kinds of solvents can be used. The amount of the solvent used is preferably 100 parts by mass or less, more preferably 90 parts by mass or less, based on 100 parts by mass of the polymerization reaction raw material from the viewpoint of the viscosity and productivity of the reaction solution.

The polymerization reaction temperature is preferably 100 to 200 ° C, more preferably 110 to 180 ° C. When the polymerization temperature is 100 ° C. or higher, the productivity tends to be improved by improving the polymerization rate and lowering the viscosity of the polymerization liquid. When the polymerization temperature is 200 ° C. or lower, the polymerization rate can be easily controlled, the formation of by-products can be suppressed, and the coloring of the resin can be suppressed. From the viewpoint of production efficiency, the polymerization reaction time is preferably 0.5 to 4 hours, more preferably 1.5 to 3.5 hours, and particularly preferably 1.5 to 3 hours. The polymerization reaction time in the case of the continuous flow type reactor is the average residence time in the reactor.

The polymerization conversion rate in the radical polymerization method is preferably 20 to 80% by mass, more preferably 30 to 70% by mass, and particularly preferably 35 to 65% by mass. When the polymerization conversion rate is 20% by mass or more, the remaining unreacted monomers can be easily removed, and the appearance of the obtained molded product tends to be good. When the polymerization conversion rate is 70% by mass or less, the viscosity of the polymerization solution tends to be low and the productivity tends to be improved.

The reactor may be either a batch reactor or a continuous flow reactor, and a continuous flow reactor is preferable from the viewpoint of productivity. In the continuous flow reaction, a polymerization reaction raw material (a mixed solution containing one or more monomers, a polymerization initiator, a chain transfer agent, etc.) is prepared under an inert atmosphere such as nitrogen, and this is fixed in a reactor. It is supplied at a flow rate, and the liquid in the reactor is drained at a flow rate corresponding to the supply amount. Examples of the reactor include a tube-type reactor that can be in a state close to a plug flow and a tank-type reactor that can be in a state close to complete mixing. The number of reactors may be one or two or more, and it is preferable to adopt a continuous flow type tank reactor for at least one reactor. The amount of liquid in the tank reactor at the time of the polymerization reaction is preferably 1/4 to 3/4, more preferably 1/3 to 2/3 with respect to the volume of the tank reactor. The reactor is usually equipped with a stirrer. Examples of the stirring device include a static stirring device and a dynamic stirring device. Examples of the dynamic agitator include a max blend type agitator, a agitator having a grid-like blade rotating around a centrally arranged vertical rotating shaft, a propeller type agitator, a screw type agitator, and the like. Above all, the Max Blend type agitator is preferable from the viewpoint of uniform mixing.

After completion of the polymerization, if necessary, volatile components such as unreacted monomers are removed. As a removal method, a heat devolatile method is preferable. Examples of the devolatile method include a balanced flash method and an adiabatic flash method. The volatilization temperature by the adiabatic flash method is preferably 200 to 280 ° C, more preferably 220 to 260 ° C. The heating time of the resin in the adiabatic flash method is preferably 0.3 to 5 minutes, more preferably 0.4 to 3 minutes, and particularly preferably 0.5 to 2 minutes. By devolatile in such a temperature range and heating time, it is easy to obtain a methacrylic resin (M1) with less coloring. The removed unreacted monomer can be recovered and used again in the polymerization reaction. The yellow index of the recovered monomer may be increased by the heat applied during the recovery operation or the like. It is preferable to purify the recovered monomer by a known method to reduce the yellow index.

Examples of the method for controlling the molecular weight distribution (Mw / Mn) include a controlled polymerization method, and a living radical polymerization method and a living anionic polymerization method are preferable. Examples of the living radical polymerization method include atom transfer radical polymerization (ATRP) method, reversible addition fragmentation chain transfer polymerization (RAFT) method, nitroxide-mediated polymerization (NMP) method, boron-mediated polymerization method, and catalytic transfer polymerization (CCT) method. Can be mentioned. (Living) As an anionic polymerization method, an organic alkali metal compound is used as a polymerization initiator and anion polymerization is carried out in the presence of a mineral salt such as a salt of an alkali metal or an alkaline earth metal (see Japanese Patent Publication No. 7-25859). ), A method of anion polymerization using an organic alkali metal compound as a polymerization initiator in the presence of an organic aluminum compound (see JP-A-11-335432), and a method of anion polymerization using an organic rare earth metal complex as a polymerization initiator (special feature). Kaihei 6-93060 (see Japanese Patent Publication No. 6-93060) and the like.

As the polymerization initiator used in the anionic polymerization method, alkyllithium such as n-butyllithium, sec-butyllithium, isobutyllithium, and tert-butyllithium are preferable. From the viewpoint of productivity, it is preferable to allow organoaluminum compounds to coexist.
Examples of the organic aluminum compound include compounds represented by the formula: Al R ¹ R ² R ³ (in the formula, R ¹ to R ³ are independently unsubstituted or an alkyl group having a substituent, and an unsubstituted or substituent. Cycloalkyl group with substituent, aryl group with unsubstituted or substituent, aralkyl group with unsubstituted or substituent, alkoxyl group with unsubstituted or substituent, aryloxy group with unsubstituted or substituent , Or N, N-disubstituted amino groups; R ² and R ³ may be unsubstituted or allylenedoxy groups having a substituent which are bonded to each other).
Organoaluminium compounds include isobutylbis (2,6-di-tert-butyl-4-methylphenoxy) aluminum, isobutylbis (2,6-di-tert-butylphenoxy) aluminum, and isobutyl [2,2'-. Methylenebis (4-methyl-6-tert-butylphenoxy)] Aluminum and the like can be mentioned.
In the anionic polymerization method, ether, a nitrogen-containing compound and the like can coexist in order to control the polymerization reaction.

(Methacrylic resin (M2))
The methacrylic resin (M2) is not particularly limited as long as the α relaxation temperature T _α2 when dynamic viscoelasticity is measured in a tensile mode and a sine wave of 1 Hz is 132 ° C. or lower. One type or two or more types of methacrylic resin (M2) can be used. The methacrylic resin (M2) contains one or more methacrylic acid ester monomer units such as MMA monomer units. Examples of the methacrylic acid ester include methacrylic acid alkyl esters such as MMA, ethyl methacrylate, and butyl methacrylate; methacrylic acid aryl esters such as phenyl methacrylate; cycloalkyl esters of methacrylic acid such as cyclohexyl methacrylate and norbornenyl methacrylate. Can be mentioned. Of these, methacrylic acid alkyl esters are preferred, and MMA is most preferred.

The content of the methacrylic acid ester monomer unit in the methacrylic resin (M2) is preferably 90% by mass or more, more preferably 95% by mass or more, still more preferably 98% by mass or more, and particularly preferably 99% by mass or more. Most preferably, it is 100% by mass.
The content of the MMA monomer unit in the methacrylic resin (M2) is preferably 90% by mass or more, more preferably 95% by mass or more, still more preferably 98% by mass or more, and particularly preferably 99% by mass or more, most preferably. Is 100% by mass.

The methacrylic resin (M2) may contain one or more monomer units other than the methacrylic acid ester monomer unit. Other monomer units include acrylic acid alkyl esters such as methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, and 2-ethylhexyl acrylate; acrylic acid aryl esters such as phenyl acrylate; Acrylic acid cycloalkyl esters such as cyclohexyl acrylate and norbornenyl acrylate; aromatic vinyl compounds such as styrene and α-methylstyrene; acrylamides and methacrylicamides; nitriles such as acrylonitrile and methacrylates in one molecule. Examples thereof include structural units derived from vinyl-based monomers having only one polymerizable carbon-carbon double bond.

The Mw of the methacrylic resin (M2) is preferably 40,000 to 200,000, more preferably 50,000 to 150,000, and particularly preferably 50,000 to 120,000. When Mw is 40,000 or more, the mechanical strength (impact resistance, toughness, etc.) of the obtained molded product tends to be improved, and when it is 200,000 or less, the fluidity of the methacrylic resin composition is improved and the moldability is improved. Tends to improve.

The molecular weight distribution (Mw / Mn) of the methacrylic resin (M2) is preferably 1.6 to 5.0, more preferably 1.7 to 4.0, and particularly preferably 1.7 to 3.0. When a methacrylic resin (M2) having a molecular weight distribution (Mw / Mn) within such a range is used, the obtained molded product has excellent mechanical strength. Mw and Mw / Mn can be controlled by adjusting the type and / or amount of the polymerization initiator used in the production of the methacrylic resin (M2).

The melt flow rate (MFR) measured under the conditions of 230 ° C. and a 3.8 kg load of the methacrylic resin (M2) is preferably 0.1 g / 10 minutes or more, more preferably 0.2 to 30 g / 10 minutes, particularly. It is preferably 0.5 to 20 g / 10 minutes, and most preferably 1.0 to 15 g / 10 minutes.

As a method for producing the methacrylic resin (M2), the polymerization temperature, the polymerization time, the type and / or amount of the chain transfer agent, the type and / or the amount of the polymerization initiator, etc. are adjusted in the radical polymerization method from the viewpoint of productivity. The method of The details of the radical polymerization method are as described above.

(Mass ratio)
The methacrylic resin composition of the present invention has a mass ratio of methacrylic resin (M1) / methacrylic resin (M2) of 2/98 to 29/71, preferably 5/95 to 28/72, and particularly preferably 10/90 to 25. / 75. The methacrylic resin (M1) having a high α relaxation temperature (T _α ) and a low thermostable decomposition property improves the heat resistance of the resin composition. However, if the amount of the methacrylic resin (M1) having a high α relaxation temperature (T _α ) is excessive, the viscosity of the resin composition at the time of molding becomes high and the moldability deteriorates. Further, since the methacrylic resin (M1) having a high α relaxation temperature (T _α ) has low heat-resistant decomposition resistance, if the amount is excessive, it may be decomposed and foamed during high-temperature molding, and the appearance of the obtained molded product may be deteriorated. .. If the amount of methacrylic resin (M1) is too small, dimensional stability with respect to desired heat cannot be obtained. The methacrylic resin (M2) having a low α relaxation temperature (T _α ) improves the moldability of the resin composition. When the mass ratios of the methacrylic resins (M1) and (M2) are in the above range, a methacrylic resin composition having both good high-temperature moldability and high dimensional stability with respect to heat of the molded body can be obtained.

The methacrylic resin composition of the present invention has η ₁ > η ₂ when the melt viscosities of the methacrylic resin (M1) and the methacrylic resin (M2) at 260 ° C. and a shear rate of 122 sec ^-1 are η ₁ and η ₂ , respectively. Is. The melt viscosity η ₁ of the methacrylic resin (M1), which has a higher α relaxation temperature than the methacrylic resin (M2), is higher than the melt viscosity η ₂ of the methacrylic resin (M2). The resulting molded product can exhibit good mechanical strength and high dimensional stability because it is easy to orient and difficult to relax. It should be noted that such an action effect can be exhibited even if the content ratio of the methacrylic resin (M1) is not large.

The total amount of the methacrylic resin (M1) and (M2) in the methacrylic resin composition of the present invention is preferably 80% by mass or more, more preferably 85% by mass or more, particularly preferably 90% by mass or more, and most preferably 92. It is mass% or more.
The methacrylic resin composition composed of only the methacrylic resins (M1) and (M2) has a Mw of preferably 50,000 to 200,000, more preferably 52,000 to 150,000, and particularly preferably 55,000 to 120,000, and has a molecular weight distribution (Mw / Mn). It is preferably 1.2 to 2.0, more preferably 1.3 to 1.8. When the Mw and the molecular weight distribution (Mw / Mn) are in such a range, the moldability of the methacrylic resin composition becomes good, and it becomes easy to obtain a molded body having excellent mechanical strength (impact resistance, toughness, etc.).
The methacrylic resin composition consisting only of the methacrylic resin (M1) and (M2) has a melt flow rate (MFR) measured at 230 ° C. and a load of 3.8 kg, preferably 0.1 g / 10 minutes or more. It is preferably 0.2 to 30 g / 10 minutes, particularly preferably 0.5 to 20 g / 10 minutes, and most preferably 1.0 to 10 g / 10 minutes.

(Other polymers)
The methacrylic resin composition of the present invention may contain one or more other polymers other than the methacrylic resin (M1) and (M2), if necessary. The other polymer may be added during or after the polymerization of the methacrylic resin (M1) and / or the methacrylic resin (M2), or may be added at the time of kneading the methacrylic resin (M1) and (M2). good.

Other polymers include polyolefin resins such as polyethylene, polypropylene, polybutene-1, poly-4-methylpentene-1, and polynorbornene; ethylene-based ionomers; polystyrene, styrene-maleic anhydride copolymers, high-impact polystyrene. , AS resin, ABS resin, AES resin, AAS resin, ACS resin, and styrene resin such as MBS resin; polyester resin such as polyethylene terephthalate and polybutylene terephthalate; polyamide resin such as nylon 6, nylon 66, and polyamide elastomer; Polycarbonate; Polyvinyl chloride, polyvinylidene chloride, polyvinylidene fluoride, polyvinyl alcohol, polyvinyl butyral, polyvinyl acetal, polyvinyl phenol, and ethylene-vinyl alcohol copolymer; polyacetal; polyurethane; modified polyphenylene ether and polyphenylene sulfide; silicone-modified resin; Acrylic rubbers, acrylic thermoplastic elastomers, and silicone rubbers; styrene-based thermoplastic elastomers such as SEPS, SEBS, and SIS; olefin-based rubbers such as IR, EPR, and EPDM. The amount of the other polymer in the methacrylic resin composition of the present invention is preferably 10% by mass or less, more preferably 5% by mass or less, and particularly preferably 0% by mass.

(Preferable aspect)
In a preferred embodiment, the methacrylic resin composition of the present invention can include a methacrylic resin (M1), (M2) and a polycarbonate resin (PC) and / or a phenoxy resin (PR). Both the polycarbonate resin (PC) and the phenoxy resin (PR) can be used alone or in combination of two or more. By including the polycarbonate resin (PC) and / or the phenoxy resin (PR), a methacrylic resin composition whose phase difference can be easily adjusted can be obtained. The amount of the polycarbonate resin (PC) and / or the phenoxy resin (PR) is preferably 1.0 to 10 parts by mass, more preferably 1 part by mass with respect to 100 parts by mass of the total amount of the methacrylic resin (M1) and (M2). .5 to 7 parts by mass, particularly preferably 2.0 to 6 parts by mass.

<Polycarbonate resin (PC)>
Examples of the polycarbonate resin (PC) include a polymer obtained by reacting a polyfunctional hydroxy compound with a carbonic acid ester-forming compound. From the viewpoint of compatibility with the methacrylic resin and the transparency of the obtained molded product, an aromatic polycarbonate resin is preferable.
Polycarbonate resin (PC) is a melt volume flow rate (MVR) measured under the conditions of 300 ° C. and 1.2 kg load from the viewpoint of compatibility with methacrylic resin and the transparency and surface smoothness of the obtained molded product. However, preferably 130-250 cm ^3/10 minutes,
It is more preferably 150 to 230 cm ^3/10 minutes, and particularly preferably 180 to 220 cm ^3/10 minutes.
The polycarbonate resin (PC) has a polystyrene-equivalent Mw of preferably 15,000 to 28,000, more preferably 18,000 to 27,000, particularly from the viewpoint of compatibility with the methacrylic resin and the transparency and surface smoothness of the obtained molded product. It is preferably 20000 to 24000.
The MVR and Mw of the polycarbonate resin (PC) can be controlled by adjusting the amount of the terminal terminator and / or the branching agent.
The Tg of the polycarbonate resin (PC) is preferably 130 ° C. or higher, more preferably 135 ° C. or higher, and particularly preferably 140 ° C. or higher. The upper limit of Tg is usually 180 ° C.

Examples of the method for producing the polycarbonate resin (PC) include a phosgene method (interfacial polymerization method) and a melt polymerization method (transesterification method). The aromatic polycarbonate resin can be produced by subjecting a polycarbonate resin raw material produced by a melt polymerization method to a treatment for adjusting the amount of terminal hydroxy groups.
The polycarbonate resin (PC) may contain other structural units such as polyester, polyurethane, polyether, or polysiloxane in addition to the polycarbonate structural unit.

<Phenoxy resin (PR)>
The phenoxy resin (PR) is a thermoplastic polyhydroxypolyether resin. The phenoxy resin (PR) can contain 50% by mass or more of one or more structural units represented by the following formula (1).

In formula (1), X is a divalent group containing at least one benzene ring, and R is a linear or branched alkylene group having 1 to 6 carbon atoms. The structural units represented by the formula (1) may be connected in any form of random, alternating, or block.
The phenoxy resin (PR) contains preferably 10 to 1000 structural units, more preferably 15 to 500, and particularly preferably 30 to 300 structural units represented by the formula (1).

It is preferable that the phenoxy resin (PR) does not have an epoxy group at the terminal because it is easy to obtain a molded product having few gel defects.
The polystyrene-equivalent Mn of the phenoxy resin (PR) is preferably 3000 to 20000000, more preferably 5000 to 100,000, and particularly preferably 10000 to 50000. When Mn is in such a range, a methacrylic resin composition having high heat resistance and high strength can be obtained.
The Tg of the phenoxy resin (PR) is preferably 80 ° C. or higher, more preferably 90 ° C. or higher, and particularly preferably 95 ° C. or higher. If the Tg of the phenoxy resin (PR) is too low, the heat resistance of the methacrylic resin composition tends to be low. The upper limit of Tg is preferably 150 ° C. If the Tg of the phenoxy resin (PR) is too high, the obtained molded product tends to be brittle.

The phenoxy resin (PR) can be obtained, for example, from a condensation reaction between a divalent phenol compound and epihalohydrin, or a double addition reaction between a divalent phenol compound and a bifunctional epoxy resin. This reaction can be carried out in no solvent or in a solvent.

Examples of the dihydric phenol compound include hydroquinone, resorcin, 4,4-dihydroxybiphenyl, 4,4'-dihydroxydiphenylketone, 2,2-bis (4-hydroxyphenyl) propane, and 1,1-bis (4-hydroxyphenyl). ) Cyclohexane, 1,1-bis (4-hydroxyphenyl) -3,3,5-trimethylcyclohexane, bis (4-hydroxyphenyl) methane, 1,1-bis (4-hydroxyphenyl) ethane, 2,2- Bis (4-hydroxyphenyl) butane, 1,1-bis (4-hydroxyphenyl) -1-phenylethane, bis (4-hydroxyphenyl) diphenylmethane, 2,2-bis (4-hydroxy-3-methylphenyl) Propane, 2,2-bis (3-phenyl-4-hydroxyphenyl) propane, 2,2-bis (4-hydroxy-3-tert-butylphenyl) propane, 1,3-bis (2- (4-hydroxy) Phenyl) propyl) benzene, 1,4-bis (2- (4-hydroxyphenyl) propyl) benzene, 2,2-bis (4-hydroxyphenyl) -1,1,1-3,3,3-hexafluoro Examples thereof include propane and 9,9'-bis (4-hydroxyphenyl) fluorene. Among them, 4,4-dihydroxybiphenyl, 4,4'-dihydroxydiphenylketone, 2,2-bis (4-hydroxyphenyl) propane, and 9,9'-bis (4-hydroxyphenyl) from the viewpoint of physical properties and cost. Fluorene is preferred.

Examples of the bifunctional epoxy resins include epoxy oligomers obtained by a condensation reaction between the above divalent phenol compound and epihalohydrin. Specifically, hydroquinone diglycidyl ether, resorcin diglycidyl ether, bisphenol S type epoxy resin, bisphenol A type epoxy resin, bisphenol F type epoxy resin, methylhydroquinone diglycidyl ether, chlorohydroquinone diglycidyl ether, 4,4'-. Dihydroxydiphenyl oxide diglycidyl ether, 2,6-dihydroxynaphthalenediglycidyl ether, dichlorobisphenol A diglycidyl ether, and tetrabromobisphenol A type epoxy resin, 9,9'-bis (4) -hydroxyphenyl) full orange glycidyl ether And so on. Among them, from the viewpoint of physical properties and cost, bisphenol A type epoxy resin, bisphenol S type epoxy resin, hydroquinone diglycidyl ether, bisphenol F type epoxy resin, tetrabromobisphenol A type epoxy resin, and 9,9'-bis (4 -hydroxy). Phenyl) full orange glycidyl ether is preferred.

Examples of the solvent used for producing the phenoxy resin (PR) include aprotic organic solvents such as methyl ethyl ketone, dioxane, tetrahydrofuran, acetophenone, N-methylpyrrolidone, dimethyl sulfoxide, N, N-dimethylacetamide, and sulfolane.
Examples of the catalyst used for producing the phenoxy resin (PR) include alkali metal hydroxides, tertiary amine compounds, tetraammonium compounds, tertiary phosphine compounds, and quaternary phosphonium compounds.

It is preferable that X in the formula (1) is a divalent group derived from the compounds represented by the following formulas (2) to (4). The positions of the two bonds constituting the divalent group are not particularly limited as long as they are chemically possible positions. It is preferable that X in the formula (1) is a divalent group having two bonds formed by extracting two hydrogen atoms from the benzene ring in the compounds represented by the formulas (2) to (4). In particular, it is preferable that the divalent group has two bonds formed by extracting one hydrogen atom from any two benzene rings in the compounds represented by the formulas (3) to (4).

式（２）中、Ｒ^４は、水素原子、炭素数１～６の直鎖若しくは分岐鎖のアルキル基、または炭素数２～６の直鎖若しくは分岐鎖のアルケニル基である。ｐは、１～４の整数である。

In formula (2), ^R4 is a hydrogen atom, a linear or branched alkyl group having 1 to 6 carbon atoms, or a linear or branched alkenyl group having 2 to 6 carbon atoms. p is an integer of 1 to 4.

式（３）中、Ｒ^１は、単結合、炭素数１～６の直鎖若しくは分岐鎖のアルキレン基、炭素数３～２０のシクロアルキレン基、または炭素数３～２０のシクロアルキリデン基である。式（３）および（４）中、Ｒ^２及びＲ^３はそれぞれ独立に、水素原子、炭素数１～６の直鎖若しくは分岐鎖のアルキル基、または炭素数２～６の直鎖若しくは分岐鎖のアルケニル基である。ｎおよびｍはそれぞれ独立に、１～４の整数である。

In formula (3), R ¹ is a single bond, a linear or branched alkylene group having 1 to 6 carbon atoms, a cycloalkylene group having 3 to 20 carbon atoms, or a cycloalkylidene group having 3 to 20 carbon atoms. .. In formulas (3) and (4), R ² and R ³ are independently hydrogen atoms, linear or branched alkyl groups having 1 to 6 carbon atoms, or linear or branched chains having 2 to 6 carbon atoms. It is an alkenyl group of. n and m are each independently an integer of 1 to 4.

In the formula (1), X may be a divalent group derived from a compound formed by condensing a plurality of benzene rings with an alicyclic or a heterocycle. For example, a divalent group derived from a compound having a fluorene structure or a carbazole structure can be mentioned.

The structural unit represented by the formula (1) is preferably a structural unit represented by the following formulas (5) and (6), and more preferably a structural unit represented by the following formula (7). The phenoxy resin (PR) of the preferred embodiment preferably contains 10 to 1000 such structural units.

In formula (5), R ⁹ is a single bond, a linear or branched alkylene group having 1 to 6 carbon atoms, a cycloalkylene group having 3 to 20 carbon atoms, or a cycloalkylidene group having 3 to 20 carbon atoms. .. In formulas (5) and (6), R ¹⁰ is a linear or branched alkylene group having 1 to 6 carbon atoms.

Examples of commercially available phenoxy resins (PR) include YP-50 and YP-50S manufactured by Nippon Steel & Sumitomo Metal Corporation, jER series manufactured by Mitsubishi Chemical Corporation, PKFE and PKHJ manufactured by InChem, and the like.

(Preferable other embodiment)
In another preferred embodiment, the methacrylic resin composition of the present invention can include methacrylic resin (M1), (M2) and crosslinked rubber (CR) and / or block copolymer (BP). Both the crosslinked rubber (CR) and the block copolymer (BP) can be used alone or in combination of two or more.

<Crosslinked rubber (CR)>
The crosslinked rubber (CR) is a polymer having rubber elasticity in which a plurality of polymer chains are crosslinked by a crosslinkable monomer having a plurality of polymerizable functional groups in one monomer. The cross-linked rubber (CR) includes an acrylic cross-linked rubber containing an acrylic acid alkyl ester monomer unit and a cross-linking monomer unit, and a diene-based rubber containing a conjugated diene-based monomer unit and a cross-linking monomer unit. Examples thereof include crosslinked rubber, crosslinked rubber containing an acrylic acid alkyl ester monomer unit, a conjugated diene-based monomer unit, and a crosslinkable monomer unit. These crosslinked rubbers can contain other vinyl-based monomer units, if necessary.

The crosslinked rubber (CR) is preferably in the form of particles. The crosslinked rubber particles (CRp) may be single-layer particles composed of only the crosslinked rubber polymer, or may be two or more layers of multilayer particles composed of the crosslinked rubber polymer and another polymer. As the multilayer particles, core-shell type particles composed of a core portion made of a crosslinked rubber polymer and a shell portion made of another polymer are preferable. In the core-shell type particles, the core portion may have a center core portion and, if necessary, one or more inner shell layers covering the center core portion, and the shell portion may have one outer shell layer covering the core portion. .. It is preferable that there are no gaps between the layers. As the core-shell type particles, acrylic multilayer polymer particles (CRa) are particularly preferable.

In the core-shell type particles, at least a part of the core portion composed of the center core portion and, if necessary, one or more inner shell layers, contains the crosslinked rubber polymer (i). If there is a residue in the core that does not contain the crosslinked rubber polymer (i), this residue contains the other polymer (iii). When a plurality of portions of the core portion contain the crosslinked rubber polymer (i), the type and physical properties of the crosslinked rubber polymer (i) contained therein may be the same or non-identical. Similarly, when the plurality of remnants of the core portion contain other polymers (iii), the types and physical properties of the other polymers (iii) contained therein may be the same or non-identical.

The crosslinked rubber polymer (i) preferably contains an acrylic acid alkyl ester monomer unit and / or a conjugated diene-based monomer unit and a crosslinkable monomer unit. The alkyl group of the acrylic acid alkyl ester monomer used in the crosslinked rubber polymer (i) preferably has 1 to 8 carbon atoms. Examples of such acrylic acid alkyl ester monomers include methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, and 2-ethylhexyl acrylate. These can be used alone or in combination of two or more. Examples of the conjugated diene-based monomer include butadiene and isoprene. These can be used alone or in combination of two or more. The amount of the acrylic acid alkyl ester monomer unit and / or the conjugated diene-based monomer unit in the crosslinked rubber polymer (i) is preferably 60% by mass or more, more preferably 70 to 99% by mass, and particularly preferably. It is 80 to 98% by mass.

Examples of the crosslinkable monomer include allyl acrylate, allyl methacrylate, 1-acryloxy-3-butene, 1-methacryloxy-3-butene, 1,2-diacryloxy-ethane, 1,2-dimethacryloxy-ethane, 1, 2-Diacryloxy-Propane, 1,3-Diacryloxy-Propane, 1,4-Diacryloxy-Butane, 1,3-Dimethacryloxy-Propane, 1,2-Dimethacryloxy-Propane, 1,4-Dimethacryloxy-butane, Triethyleneglycoldi Examples thereof include methacrylate, hexanediol dimethacrylate, triethylene glycol diacrylate, hexanediol diacrylate, divinylbenzene, 1,4-pentadiene, and triallyl isocyanate. These can be used alone or in combination of two or more. The amount of the crosslinkable monomer unit in the crosslinked rubber polymer (i) is preferably 0.05 to 10% by mass, more preferably 0.5 to 7% by mass, and particularly preferably 1 to 5% by mass. ..

The crosslinked rubber polymer (i) can contain other vinyl-based monomer units, if necessary. Other vinyl-based monomers include methacrylic acid ester monomers such as MMA, ethyl methacrylate, butyl methacrylate, and cyclohexyl methacrylate; aromatic vinyls such as styrene, p-methylstyrene, and o-methylstyrene. Monomer; Maleimide-based monomers such as N-propylmaleimide, N-cyclohexylmaleimide, and NO-chlorophenylmaleimide can be mentioned. These can be used alone or in combination of two or more.

As the other polymer (iii), one having a methacrylic acid alkyl ester monomer unit is preferable. The other polymer (iii) can optionally contain crosslinkable monomer units and / or other vinyl-based monomer units.
The methacrylic acid alkyl ester monomer used in the other polymer (iii) has preferably 1 to 8 carbon atoms. Examples of such methacrylic acid alkyl ester monomers include MMA, ethyl methacrylate, butyl methacrylate and the like, and MMA is preferable. These can be used alone or in combination of two or more. The amount of the methacrylic acid alkyl ester monomer unit in the other polymer (iii) is preferably 80 to 100% by mass, more preferably 85 to 99% by mass, and particularly preferably 90 to 98% by mass.
As the crosslinkable monomer used for the other polymer (iii), the same crosslinkable monomer as the crosslinkable monomer exemplified in the crosslinked rubber polymer (i) can be used. The amount of the crosslinkable monomer unit in the other polymer (iii) is preferably 0 to 5% by mass, more preferably 0.01 to 3% by mass, and particularly preferably 0.02 to 2% by mass. ..

Other vinyl-based monomers used in the other polymer (iii) include methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, hexyl acrylate, cyclohexyl acrylate, phenyl acrylate, and acrylate. Acrylic acid ester monomers such as benzyl and 2-ethylhexyl acrylate; vinyl acetate; aromatic vinyl such as styrene, p-methylstyrene, m-methylstyrene, o-methylstyrene, and α-methylstyrene, vinylnaphthalene. Monomers; nitriles such as acrylonitrile and methacrylonitrile; α, β-unsaturated carboxylic acids such as acrylic acid, methacrylic acid, and crotonic acid; maleimide-based monomers such as N-ethylmaleimide and N-cyclohexylmaleimide. Can be mentioned. These can be used alone or in combination of two or more.

In the core-shell type particles, the shell portion composed of one or more outer shell layers preferably contains a thermoplastic polymer (ii). The thermoplastic polymer (ii) preferably has a methacrylic acid alkyl ester monomer unit and, if necessary, contains another vinyl-based monomer unit. It is preferable that at least a part of the thermoplastic polymer (ii) is grafted to the center core layer or the inner shell layer adjacent to the inside.

The carbon number of the methacrylic acid alkyl ester monomer unit in the thermoplastic polymer (ii) is preferably 1 to 8. Examples of such methacrylic acid alkyl ester monomers include MMA and butyl methacrylate, and MMA is preferable. These can be used alone or in combination of two or more. The amount of the methacrylic acid alkyl ester monomer unit in the thermoplastic polymer (ii) is preferably 80% by mass or more, more preferably 85% by mass or more, and particularly preferably 90% by mass or more.

As the other vinyl-based monomer used for the thermoplastic polymer (ii), the same ones as those of the other vinyl-based monomers exemplified in the above-mentioned other polymer (iii) can be used. The amount of the other vinyl-based monomer unit in the thermoplastic polymer (ii) is preferably 20% by mass or less, more preferably 15% by mass or less, and particularly preferably 10% by mass or less.

As for the configuration of the core portion and the shell portion in the core-shell type particles, the center core portion is composed of the crosslinked rubber polymer (i) and the outer shell layer is composed of the thermoplastic polymer (ii). Is composed of another polymer (iii), the inner shell layer is composed of the crosslinked rubber polymer (i), and the outer shell layer is composed of the thermoplastic polymer (ii). Three-layer polymer particles consisting of a type of crosslinked rubber polymer (i), an inner shell layer consisting of another type of crosslinked rubber polymer (i), and an outer shell layer consisting of a thermoplastic polymer (ii); Three-layer polymer particles in which the center core portion is made of a crosslinked rubber polymer (i), the inner shell layer is made of another polymer (iii), and the outer shell layer is made of a thermoplastic polymer (ii); the center core portion. Is composed of the crosslinked rubber polymer (i), the first inner shell layer is composed of another polymer (iii), the second inner shell layer is composed of the crosslinked rubber polymer (i), and the outer shell layer is thermoplastic. Examples thereof include 4-layer polymer particles made of coalesced (ii).

Among the above, the center core portion is made of another polymer (iii), the inner shell layer is made of a crosslinked rubber polymer (i), and the outer shell layer is made of a thermoplastic polymer (ii). Combined particles are preferred. Further, the other polymer (iii) in the center core portion has an MMA monomer unit of 80 to 99.95% by mass and an alkyl group having 1 to 8 carbon atoms, and the acrylic acid alkyl ester monomer unit has 0 to 19. Acrylic acid which is a copolymer of 95% by mass and 0.05 to 2% by mass of a crosslinkable monomer unit, and the crosslinked rubber polymer (i) of the inner shell layer has an alkyl group having 1 to 8 carbon atoms. It is a copolymer of an alkyl ester monomer unit of 80 to 98% by mass, an aromatic vinyl monomer unit of 1 to 19% by mass, and a crosslinkable monomer unit of 1 to 5% by mass, and has a thermoplastic weight of the outer shell layer. The coalescence (ii) is an acrylic three-layered polymer in which the MMA monomer unit is 80 to 100% by mass and the acrylic acid alkyl ester monomer unit having an alkyl group having 1 to 8 carbon atoms is 0 to 20% by mass. Combined particles are particularly preferred.

From the viewpoint of the transparency of the core-shell type particles, the difference in the refractive index of the adjacent layers is preferably less than 0.005, more preferably less than 0.004, and particularly preferably less than 0.003. It is preferable to select a polymer.
The proportion of the outer shell layer in the core-shell type particles is preferably 10 to 60% by mass, more preferably 15 to 50% by mass, and particularly preferably 20 to 40% by mass. The proportion of the portion containing the crosslinked rubber polymer (i) in the core portion is preferably 20 to 100% by mass, more preferably 30 to 70% by mass.

The volume-based average particle diameter of the crosslinked rubber particles (CRp) is preferably 0.02 to 1 μm, more preferably 0.05 to 0.5 μm, and particularly preferably 0.1 to 0.3 μm. When crosslinked rubber particles (CRp) having such a volume-based average particle diameter are used, the appearance defects of the obtained molded product can be significantly reduced. In the present specification, the "volume-based average particle size" is a value calculated based on the particle size distribution data measured by the light scattered light method.

As a method for producing crosslinked rubber particles (CRp), an emulsification polymerization method or a seed emulsification polymerization method is preferable from the viewpoint of controlling the particle size and easiness of producing a multilayer structure. The emulsion polymerization method is a method for producing an emulsion containing polymer particles by emulsion-polymerizing one or more kinds of raw material monomers. In the seed emulsion polymerization method, one or more kinds of raw material monomers are emulsified and polymerized to obtain seed particles, and then other raw material monomers are emulsified and polymerized in the presence of the seed particles to obtain the seed particles and the seed particles. An emulsion containing core-shell polymer particles comprising a shell layer covering the above can be produced. An emulsion containing core-shell multilayer polymer particles composed of seed particles and a plurality of shell layers covering the seed particles by repeating the step of emulsion-polymerizing one or more kinds of raw material monomers in the presence of the obtained core-shell polymer particles. Can be manufactured.

Examples of the emulsifier used in the emulsification polymerization method include anionic emulsifiers, nonionic emulsifiers, and nonionic / anionic emulsifiers. Examples of the anionic emulsifier include dialkyl sulfosuccinates such as sodium dioctyl sulfosuccinate and sodium dilauryl sulfosuccinate; alkylbenzene sulfonates such as sodium dodecylbenzene sulfonate; and alkyl sulfates such as sodium dodecyl sulphate. Examples of the nonionic emulsifier include polyoxyethylene alkyl ether and polyoxyethylene nonylphenyl ether. Nonionic anionic emulsifiers include polyoxyethylene nonylphenyl ether sulfates such as polyoxyethylene nonylphenyl ether sodium sulfate; polyoxyethylene alkyl ether sulfates such as polyoxyethylene alkyl ether sodium sulfate: polyoxyethylene tridecyl ethers. Examples thereof include alkyl ether carboxylates such as sodium acetate. These can be used alone or in combination of two or more. The average number of repeating units of ethylene oxide (EO) in the examples of the nonionic emulsifier and the nonionic / anion emulsifier is preferably 30 or less, more preferably 30 or less, in order to prevent the emulsifier from becoming extremely foamable. It is 20 or less, particularly preferably 10 or less.
Examples of the polymerization initiator used for emulsion polymerization include persulfate-based initiators such as potassium persulfate and ammonium persulfate; and redox-based initiators such as persulfoxylate / organic peroxide and persulfate / sulfate. Be done.

Examples of the method for separating crosslinked rubber particles (CRp) from the emulsion obtained by emulsion polymerization include a salting out coagulation method, a freeze coagulation method, and a spray drying method. Among them, the salting out coagulation method and the freeze coagulation method are preferable, and the freeze coagulation method is more preferable, because impurities contained in the crosslinked rubber particles (CRp) can be easily removed by washing with water. According to the freeze-coagulation method that does not use a flocculant, it is easy to obtain a resin composition having excellent water resistance. It is preferable to filter the emulsion with a wire mesh having a mesh size of 50 μm or less before the solidification step because foreign substances mixed in the emulsion can be removed.

From the viewpoint of particle dispersibility in the melt-kneading of the methacrylic resin (M1) and (M2) and the crosslinked rubber particles (CRp), the crosslinked rubber particles (CRp) are preferably compacted with a diameter of 1000 μm or less, more preferably 500 μm or less. It is preferable to take it out in the form of an aggregate. Examples of the aggregated form include a form in which the shell portions are mutually fused. Examples of the shape of the crosslinked rubber particle aggregate include pellets, powders, granules, and the like.

The amount of the crosslinked rubber (CR) in the methacrylic resin composition of the present invention is preferably 5 to 30 parts by mass, more preferably 10 to 10 parts by mass with respect to 100 parts by mass of the total amount of the methacrylic resin (M1) and (M2). It is 25 parts by mass, particularly preferably 15 to 20 parts by mass.

Dispersion auxiliary particles (DA) such as methacrylic resin particles can be added to the methacrylic resin composition of the present invention in order to enhance the uniform dispersibility of the crosslinked rubber particles (CRp). The volume-based average particle size of the dispersion auxiliary particles (DA) is preferably smaller than that of the crosslinked rubber particles (CRp), preferably 0.04 to 0.12 μm, and more preferably 0.05 to 0.1 μm. From the viewpoint of the effect of improving dispersibility and the like, the mass ratio of the dispersion auxiliary particles (DA) / crosslinked rubber particles (CRp) is preferably 0/100 to 60/40, more preferably 10/90 to 50/50, and particularly preferably. Is 20/80 to 40/60.

<Block Copolymer (BP)>
A block copolymer (BP) is a copolymer in which a plurality of types of polymer molecular chains (polymer blocks) are connected in a chain or radial manner as a whole. From the viewpoint of compatibility with the methacrylic resins (M1) and (M2), at least one of the polymer blocks constituting the block copolymer (BP) contains 90% by mass or more of the methacrylic acid ester monomer unit. Combined, polymer containing styrene monomer unit and acrylonitrile monomer unit, polymer containing styrene monomer unit and anhydrous maleic acid monomer unit, styrene monomer unit and anhydrous maleic acid monomer It is preferable to contain a polymer containing a unit and an MMA monomer unit, or polyvinyl butyral.

From the viewpoint of improving the strength of the molded product, the block copolymer (BP) is one or more polymer blocks (b1) (methacrylic acid ester polymers) made of a polymethacrylic acid ester such as polymethylmethacrylate (PMMA). A block copolymer (BPa) containing one or more polymer blocks (b2) (acrylic acid ester polymer blocks) composed of a polyacrylic acid ester and a polyacrylic acid ester is preferable.
As a method for producing a block copolymer (BPa), a living polymerization is used to create a polymerization start point at the end of one polymer block, and a monomer is polymerized from this start point to connect the other polymer blocks. Method for producing; Examples thereof include a method in which a plurality of types of polymer blocks are prepared and these are subjected to an addition reaction or a condensation reaction.

The amount of the block copolymer (BP) is preferably 0.1 to 30 parts by mass, more preferably 0.5 to 25 parts by mass with respect to 100 parts by mass of the total amount of the methacrylic resin (M1) and (M2). Particularly preferably 1 to 20 parts by mass.

(Other optional ingredients)
The methacrylic resin composition of the present invention may contain other optional components, if necessary. Other optional ingredients include fillers, antioxidants, thermal degradation agents, UV absorbers, light stabilizers, lubricants, mold release agents, polymer processing aids, antistatic agents, flame retardants, dyes and pigments, and light diffusion. Examples thereof include various additives such as agents, organic pigments, matting agents, impact resistance modifiers, and phosphors. The total amount of these various additives is preferably 7% by mass or less, more preferably 5% by mass or less, and particularly preferably 4% by mass or less.

<Ultraviolet absorber (LA)>
If the molecular weight of the ultraviolet absorber (LA) is too small, foaming may occur during molding of the methacrylic resin composition. Therefore, the molecular weight of the ultraviolet absorber (LA) is preferably more than 200, more preferably 300 or more, particularly preferably 500 or more, and most preferably 600 or more.
An ultraviolet absorber (LA) is a compound that is said to have a function of converting light energy into heat energy. Examples of the ultraviolet absorber (LA) include benzophenones, benzotriazoles, triazines, benzoates, salicylates, cyanoacrylates, oxalic acid anilides, malonic acid esters, and formamidines. These can be used alone or in combination of two or more. Benzotriazoles (compounds having a benzotriazole skeleton) and triazines (compounds having a triazine skeleton) are preferable because they have a high effect of suppressing deterioration (yellowing and the like) of the resin due to ultraviolet rays.

Examples of benzotriazoles include 2- (2H-benzotriazole-2-yl) -4- (1,1,3,3-tetramethylbutyl) phenol (manufactured by BASF; trade name: TINUVIN329), 2- (2H-). Benzotriazole-2-yl) -4,6-bis (1-methyl-1-phenylethyl) phenol (manufactured by BASF; trade name: TINUVIN234), 2,2'-methylenebis [6- (2H-benzotriazole-2) -Il) -4-tert-octylphenol] (manufactured by ADEKA; LA-31), 2- (5-octylthio-2H-benzotriazole-2-yl) -6-tert-butyl-4-methylphenol, etc. Can be mentioned.

Examples of triazines include 2,4,6-tris (2-hydroxy-4-hexyloxy-3-methylphenyl) -1,3,5-triazine (made by ADEKA; LA-F70) and its analogs. Certain hydroxyphenyltriazine-based ultraviolet absorbers (manufactured by BASF; CGL777, TINUVIN460, TINUVIN479, etc.), 2,4- diphenyl -6- (2-hydroxy-4-hexyloxyphenyl) -1,3,5-triazine, etc. Can be mentioned.

In addition, an ultraviolet absorber having a maximum molar absorption coefficient ε _max at a wavelength of 380 to 450 nm of 1200 dm ³ · mol ^-1 cm ^-1 or less can be mentioned. Examples of such an ultraviolet absorber include 2-ethyl-2'-ethoxy-oxalanilide (manufactured by Clariant Japan Co., Ltd .; trade name: Sandeuboa VSU) and the like.

In addition, International Publication No. 2011/087944, International Publication No. 2012/12395, Japanese Patent Application Laid-Open No. 2012-012476, Japanese Patent Application Laid-Open No. 2013-0234661, Japanese Patent Application Laid-Open No. 2013-112790, Japanese Patent Application Laid-Open No. 2013-194037, Examples thereof include metal complexes having a ligand having a heterocyclic structure described in JP-A-2014-62228, JP-A-2014-88542, JP-A-2014-88543 and the like. Examples of such a metal complex include a compound represented by the following formula (A).

In formula (A), M is a metal atom. Y ¹ to Y ⁴ are independently divalent groups other than carbon atoms (oxygen atom, sulfur atom, NH, NR ⁵ , etc.). R ⁵ is a substituent such as an alkyl group, an aryl group, a heteroaryl group, a heteroaralkyl group, and an aralkyl group. The substituent may further have a substituent. Z ¹ and Z ² are independently trivalent groups (nitrogen atom, CH, CR ⁶ , etc.). R ⁶ is a substituent such as an alkyl group, an aryl group, a heteroaryl group, a heteroaralkyl group, and an aralkyl group. The substituent may further have a substituent. R ¹ to R ⁴ are independently hydrogen atom, alkyl group, hydroxyl group, carboxyl group, alkoxyl group, halogeno group, alkylsulfonyl group, monophorinosulfonyl group, piperidinosulfonyl group, thiomorpholinosulfonyl group, and It is a substituent such as a piperadinosulfonyl group. The substituent may further have a substituent. a to d represent the numbers of R ¹ to R ⁴ , respectively, and are independently integers of 1 to 4.

Examples of the ligand having a heterocyclic structure in the above metal complex include 2,2'-imidazolebenzothiazole, 2- (2-benzothiazolylamino) benzoxazole, and 2- (2-benzothiazolylamino) benzo. Imidazole, (2-benzothiazolyl) (2-benzoimidazolyl) methane, bis (2-benzoxazolyl) methane, bis (2-benzothiazolyl) methane, bis [2- (N-substituted) benzoimidazolyl] methane, and derivatives thereof. And so on. As the central metal of the metal complex, copper, nickel, cobalt, zinc and the like are preferable. The metal complex is preferably used by being dispersed in a medium such as a small molecule compound or a polymer. The amount of the metal complex added is preferably 0.01 to 5 parts by mass, more preferably 0.1 to 2 parts by mass with respect to 100 parts by mass of the methacrylic resin composition of the present invention. Since the metal complex has a large molar absorption coefficient at a wavelength of 380 to 400 nm, a small amount can be added to obtain a desired ultraviolet absorption effect. Therefore, deterioration of the appearance of the molded product due to bleed-out or the like can be suppressed. Further, since the metal complex has high heat resistance, there is little deterioration and decomposition during molding. Further, since the metal complex has high light resistance, the ultraviolet absorption performance can be maintained for a long period of time.

The maximum value ε _max of the molar extinction coefficient of the ultraviolet absorber can be measured as follows. 10.00 mg of an ultraviolet absorber is added to 1 L of cyclohexane and dissolved by visual observation so that there are no undissolved substances. This solution is injected into a quartz glass cell of 1 cm × 1 cm × 3 cm, and the absorbance at a wavelength of 380 to 450 nm is measured using a U-4341 spectrophotometer manufactured by Hitachi, Ltd. From the molecular weight (MUV) of the _ultraviolet absorber and the maximum value (A _max ) of the measured absorbance, the maximum value ε _max of the molar extinction coefficient is calculated by the following equation.
ε _max = [A _max / (10 × 10 ^-3 )] × M _UV

<Polymer processing aid (PA)>
As the polymer processing aid (PA), polymer particles (non-crosslinked rubber particles) having a particle diameter of 0.05 to 0.5 μm, which can be produced by an emulsification polymerization method, can be used. The polymer particles may be single-layer particles composed of a polymer having a single composition and a single extreme viscosity, or may be two or more layers of multilayer particles composed of two or more kinds of polymers having different compositions or extreme viscosities. You may. Among them, particles having a two-layer structure having a polymer layer having a low ultimate viscosity in the inner layer and a polymer layer having a high ultimate viscosity of 5 dl / g or more in the outer layer are preferable. The polymer processing aid (PA) preferably has an ultimate viscosity of 3 to 6 dl / g. If the ultimate viscosity is too small, the effect of improving the moldability may be insufficient, and if it is too large, the moldability of the methacrylic resin composition may be deteriorated. Specific examples thereof include the Metabren-P series manufactured by Mitsubishi Rayon and the Pararoid series manufactured by Dow. The amount of the polymer processing aid (PA) is preferably 0.1 to 5 parts by mass with respect to 100 parts by mass of the total amount of the methacrylic resin (M1) and (M2). If the blending amount is too small, good processing characteristics cannot be obtained, and if the blending amount is too large, the appearance of the molded product may be deteriorated.

<Other additives>
Examples of the filler include calcium carbonate, talc, carbon black, titanium oxide, silica, clay, barium sulfate, magnesium carbonate and the like. The amount of the filler in the methacrylic resin composition of the present invention is preferably 3% by mass or less, more preferably 1.5% by mass or less.

Examples of the antioxidant include phosphorus-based antioxidants, hindered phenol-based antioxidants, and thioether-based antioxidants. One or more kinds of antioxidants can be used. Among them, phosphorus-based antioxidants and hindered phenol-based antioxidants are preferable, and the combined use of phosphorus-based antioxidants and hindered phenol-based antioxidants is more preferable, from the viewpoint of the effect of preventing deterioration of optical properties due to coloring. When a phosphorus-based antioxidant and a hindered phenol-based antioxidant are used in combination, the mass ratio of the phosphorus-based antioxidant: the hindered phenol-based antioxidant is preferably 1: 5 to 2: 1, preferably 1: 2. ~ 1: 1 is more preferable.
Phosphorus antioxidants include 2,2-methylenebis (4,6-dit-butylphenyl) octylphosphite (manufactured by ADEKA; trade name: ADEKA STAB HP-10), tris (2,4-dit-). Butylphenyl) phosphite (manufactured by BASF; trade name: IRGAFOS168), and 3,9-bis (2,6-di-tert-butyl-4-methylphenoxy) -2,4,8,10-tetraoxa3 9-Diphosphaspiro [5.5] Undecan (manufactured by ADEKA; trade name: ADEKA STAB PEP-36) and the like can be mentioned.
Examples of the hindered phenolic antioxidant include pentaerythrityl-tetrakis [3- (3,5-dit-butyl-4-hydroxyphenyl) propionate] (manufactured by BASF; trade name IRGANOX1010) and octadecyl-3-3. Examples thereof include (3,5-dit-butyl-4-hydroxyphenyl) propionate (manufactured by BASF; trade name IRGANOX1076).

The thermal degradation inhibitor can prevent thermal degradation of the resin by capturing the polymer radicals generated when exposed to high heat under substantially oxygen-free conditions. Examples of the heat deterioration inhibitor include 2-t-butyl-6- (3'-t-butyl-5'-methyl-hydroxybenzyl) -4-methylphenyl acrylate (manufactured by Sumitomo Chemical Co., Ltd .; trade name: Sumilyzer GM), and 2,4-dit-amyl-6- (3', 5'-dit-amyl-2'-hydroxy-α-methylbenzyl) phenyl acrylate (manufactured by Sumitomo Chemical Co., Ltd .; trade name Sumilyzer GS) and the like can be mentioned. ..

The light stabilizer is a compound that is said to have a function of capturing radicals generated by oxidation by light. Examples thereof include hindered amines such as compounds having a 2,2,6,6-tetraalkylpiperidine skeleton.
Examples of the lubricant include stearic acid, behenic acid, stearoamic acid, methylenebisstearoamide, hydroxystearic acid triglyceride, paraffin wax, ketone wax, octyl alcohol, and hydrogenated oil.
Examples of the release agent include higher alcohols such as cetyl alcohol and stearyl alcohol; and glycerin higher fatty acid esters such as stearic acid monoglyceride and stearic acid diglyceride. The combined use of higher alcohols and glycerin fatty acid monoester is preferable. The mass ratio of the higher alcohols / glycerin fatty acid monoester is preferably 2.5 / 1 to 3.5 / 1, more preferably 2.8 / 1 to 3.2 / 1.

As the organic dye, a compound that converts ultraviolet rays into visible light is preferably used.
Examples of the light diffusing agent and the matting agent include glass fine particles, polysiloxane-based crosslinked fine particles, crosslinked polymer fine particles, talc, calcium carbonate, barium sulfate and the like.
Examples of the fluorescent substance include fluorescent pigments, fluorescent dyes, fluorescent white dyes, fluorescent whitening agents, fluorescent bleaching agents and the like.

(Physical characteristics of methacrylic resin composition)
The methacrylic resin composition of the present invention preferably has Mw of 50,000 to 200,000, more preferably 55,000 to 160,000, particularly preferably 60,000 to 120,000, most preferably 70,000 to 100,000, and preferably has a molecular weight distribution (Mw / Mn). It is 1.0 to 5.0, more preferably 1.2 to 3.0, particularly preferably 1.3 to 2.0, and most preferably 1.3 to 1.7. When the Mw and the molecular weight distribution (Mw / Mn) are in such a range, the moldability of the methacrylic resin composition becomes good, and it becomes easy to obtain a molded body having excellent mechanical strength (impact resistance, toughness, etc.).

The melt flow rate (MFR) measured under the conditions of 230 ° C. and a 3.8 kg load of the methacrylic resin composition of the present invention is preferably 0.1 to 30 g / 10 minutes, more preferably 0.5 to 20 g / 10. Minutes, particularly preferably 1.0 to 15 g / 10 minutes.
The methacrylic resin composition of the present invention has a haze of preferably 3.0% or less, more preferably 2.0% or less, and particularly preferably 1.5% or less when processed into a film having a thickness of 3.2 mm. be.

(Manufacturing method of methacrylic resin composition)
Examples of the method for producing the methacrylic resin composition of the present invention include a method of melt-kneading the methacrylic resin (M1), (M2) and, if necessary, another polymer. The melt-kneading can be performed by using a melt-kneading device such as a kneader luda, an extruder, a mixing roll, and a Banbury mixer. The kneading temperature can be appropriately adjusted according to the softening temperature of the methacrylic resin (M1), (M2), and other polymers used as needed, and is usually in the range of 150 ° C to 300 ° C. The shear rate during kneading can be adjusted within the range of 10 to 5000 sec ^-1 .
As another method for producing the methacrylic resin composition of the present invention, in the presence of one of the methacrylic resins (M1) and (M2) and, if necessary, another polymer used, the other methacrylic There is a method of polymerizing the resin. Compared with the above-mentioned production method, this production method has a shorter heat history applied to the methacrylic resin, so that thermal decomposition of the methacrylic resin is suppressed, and a methacrylic resin composition with less coloring and foreign matter can be easily obtained.
The methacrylic resin composition of the present invention can be in the form of pellets or the like in order to enhance convenience during storage, transportation, or molding.

"Molded body"
The molded product of the present invention is a molded product of the above-mentioned methacrylic resin composition of the present invention. The molding method includes a T-die method (lamination method, coextrusion method, etc.), inflation method (coextrusion method, etc.), compression molding method, blow molding method, calendar molding method, vacuum molding method, injection molding method (insert method, etc.). A melt molding method such as a two-color method, a pressing method, a core back method, and a sandwich method); a solution casting method and the like can be mentioned. Among them, the T-die method, the inflation method, the injection molding method and the like are preferable from the viewpoint of productivity, cost and the like.

"the film"
The form of the molded body is arbitrary, and examples thereof include a film. The film of the present invention is a film made of the above-mentioned methacrylic resin composition of the present invention. Normally, a planar molded product having a thickness of 5 to 250 μm is mainly classified as a “film”, and a planar molded product having a thickness of more than 250 μm is mainly classified as a “sheet”. And it is called "film".

Examples of the film forming method include a melt film forming method and a solution film forming method, and the melt film forming method is preferable from the viewpoint of productivity. Examples of the melt film forming method include an inflation method, a T-die method, a calendar method, and a cutting method. Above all, the T-die method is preferable. Examples of the melt film forming apparatus include an extruder type melt extrusion apparatus having a single-screw or biaxial extrusion screw. The melt extrusion temperature is preferably 150 to 350 ° C, more preferably 200 to 300 ° C. When melt-kneading using a melt extruder, it is preferable to perform melt-kneading under reduced pressure or under an inert atmosphere such as nitrogen from the viewpoint of suppressing coloring. It is preferable to install a polymer filter for removing foreign matter and a gear pump for improving the thickness accuracy in the melt extruder.

Since the extrusion molding method provides a film with good surface smoothness, good mirror gloss, and low haze, the methacrylic resin composition is extruded from the T-die in a molten state, which is then subjected to one or more cooling mirror surfaces. A method of cooling by contacting or sandwiching the roll or mirror surface belt is preferable. The mirror surface roll or mirror surface belt preferably has at least a mirror surface made of chrome-plated metal.

The thickness of the methacrylic resin film (unstretched film) formed by the above method is preferably 10 to 500 μm, more preferably 20 to 200 μm from the viewpoint of mechanical strength, film uniformity, and winding property. .. The thickness distribution is preferably within ± 10%, more preferably within ± 5%, and particularly preferably within ± 3% with respect to the average value. If the thickness distribution exceeds ± 10%, uneven stretching may occur when the stretching treatment is performed.

The methacrylic resin film (unstretched film) formed by the above method may be subjected to a stretching treatment. By the stretching treatment, the mechanical strength (impact resistance, toughness, etc.) and thermal characteristics are increased, and a film that is not easily cracked can be obtained. The stretching process includes a stretching step, a heat fixing step, and a relaxing step. Examples of the stretching method include a sequential biaxial stretching method, a simultaneous biaxial stretching method, and a tuber stretching method.

In the case of the sequential biaxial stretching method, the stretching speed is preferably 1 to 8,000% / min, more preferably 100 to 6,000% / min in any stretching direction. The stretching speed may be the same or non-same in the two directions. In the case of the simultaneous biaxial stretching method, the stretching speed is preferably 1 to 8,000% / min, more preferably 50 to 6,000% / min. In either method, if the stretching speed is too low, the productivity is not good, and if the stretching speed is too high, film breakage may occur.

The stretching temperature is preferably Tg to (Tg + 30 ° C.), more preferably (Tg + 5 ° C.) to (Tg + 25 ° C.) in any of the sequential / simultaneous biaxial stretching methods based on Tg of the methacrylic resin composition of the present invention. Is. In such a range, thickness unevenness is suppressed. If the stretching temperature is too low, the film may break, and if the stretching temperature is too high, the effect of improving the mechanical strength and thermal characteristics of the stretching treatment may be insufficient.

The area magnification of the stretched film with respect to the unstretched film is preferably 1.01 to 12.25 times, more preferably 1.10 to 9 times. If the draw ratio is less than 1.01 times, the effect of improving the mechanical strength of the film is insufficient, and if it exceeds 12.25 times, the mechanical strength may decrease. In the case of biaxial stretching, the stretching ratio in each axial direction is preferably 1.01 to 3.5 times.

The film of the present invention is coated with a polarizing element protective film, a retardation film, a liquid crystal protective film, a surface material of a portable information terminal, a display window protective film of a portable information terminal, a light guide film, silver nanowires or carbon nanotubes on the surface. It is suitable for a transparent conductive film, a front film of various displays, and the like, and is particularly suitable for a polarizing element protective film and the like.
In addition, the film of the present invention includes IR (infrared) cut film, security film, shatterproof film, decorative film, metal decorative film, solar cell back sheet, flexible solar cell front sheet, shrink film, in-mold. It is suitable for a label film, a gas barrier film, and the like.
The film of the present invention is also suitable for an optical film for an organic electroluminescence (EL) illuminator.

"Laminate film"
The film of the present invention (unstretched film or stretched film) may be in the form of a laminated film in which another layer is laminated on at least one surface. The laminated film of the present invention has a layer made of the above-mentioned film of the present invention (unstretched film or stretched film).
Examples of other layers include various functional layers. Examples of the functional layer include a hard coat layer, an anti-glare layer, an antireflection layer, an anti-sticking layer, a diffusion layer, an antiglare layer, an antistatic layer, an antifouling layer, and an easily slippery layer containing fine particles and the like.

The other layer may be a stator made of an iodine-doped polyvinyl alcohol film. The polarizing plate, which is one aspect of the laminated film of the present invention, has the above-mentioned polarizing element and the stator-protecting film made of the above-mentioned film of the present invention laminated on at least one surface thereof. In the embodiment in which the film of the present invention is laminated on one surface of the polarizing element, any optical film other than the film of the present invention can be laminated on the other surface of the polarizing element, if necessary. Examples of the optional optical film include a polarizing element protective film other than the film of the present invention, a viewing angle adjusting film, a retardation film, a brightness improving film, and the like. Lamination can be done via an adhesive layer, if desired.

The polarizing plate of the above aspect can be used for an image display device. Examples of the image display device include a self-luminous display device such as an (organic) electroluminescence display (ELD), a plasma display (PD), and a field emission display (FED); a liquid crystal display device (LCD) and the like. Will be. The LCD has a liquid crystal cell and a polarizing plate arranged on at least one side thereof.

The other layer may be a layer composed of a metal and / or a metal oxide. Examples of the metal include aluminum, silicon, magnesium, palladium, zinc, tin, nickel, silver, copper, gold, indium, stainless steel, chromium, titanium and the like. Examples of the metal oxide include aluminum oxide, zinc oxide, antimony oxide, indium oxide, calcium oxide, cadmium oxide, silver oxide, gold oxide, chromium oxide, silicon oxide, cobalt oxide, zirconium oxide, tin oxide and titanium oxide. Examples thereof include iron oxide, copper oxide, nickel oxide, platinum oxide, palladium oxide, bismuth oxide, magnesium oxide, manganese oxide, molybdenum oxide, vanadium oxide, and barium oxide. These metals and metal oxides can be used alone or in combination of two or more. Among them, indium has excellent designability because it has excellent luster, and is preferable because luster is not easily lost even when a laminated film in which a metal layer is laminated on the film of the present invention is formed by deep drawing. Further, since aluminum has excellent gloss and has excellent designability and can be obtained industrially at low cost, it is particularly preferable for applications that do not require deep drawing. The vacuum deposition method is usually used as a method for forming a layer composed of a metal and / or a metal oxide, but a method such as ion plating, sputtering, and CVD (Chemical Vapor Deposition) may also be used. good. Before forming a layer made of a metal and / or a metal oxide, the film of the present invention may be subjected to a surface treatment such as a corona treatment in advance. The thickness of the layer made of a metal and / or a metal oxide is generally about 5 to 100 nm, and 5 to 250 nm is preferable when deep drawing is performed after the layer is formed.

The other layer may be a layer made of another thermoplastic resin. Other thermoplastic resins suitable for lamination include polycarbonate resin, polyethylene terephthalate resin, polyamide resin, polyethylene resin, polypropylene resin, polystyrene resin, polyvinyl chloride resin, other (meth) acrylic resin, and ABS (acrylonitrile-butadiene-). Examples thereof include styrene copolymer resin, ethylene vinyl alcohol resin, polyvinyl butyral resin, polyvinyl acetal resin, styrene-based thermoplastic elastomer, olefin-based thermoplastic elastomer, and acrylic-based thermoplastic elastomer. The thickness of the layer made of these thermoplastic resins is appropriately designed according to the intended use and is not particularly limited, and is preferably 500 μm or less from the viewpoint of secondary processability.
The method for producing a laminated film having a layer made of another thermoplastic resin is not particularly limited. For example, (1) a method of continuously laminating a separately prepared film of the present invention and another thermoplastic resin film between a pair of heating rolls; (2) separately prepared films of the present invention and others. (3) The film of the present invention and another thermoplastic resin film are prepared separately, and one film is pressure-pneumatically or vacuum-formed at the same time as the other. (4) A method of laminating a separately prepared film of the present invention and another thermoplastic resin film via an adhesive layer (wet lamination method); (5) a book prepared in advance. A method of laminating another thermoplastic resin melt-extruded from a T-die onto the film of the present invention; (6) a method of co-extruding the methacrylic resin composition of the present invention with another thermoplastic resin and the like can be mentioned.

"Laminate molded body"
The laminated molded article of the present invention is obtained by laminating the above-mentioned film of the present invention or the above-mentioned laminated film of the present invention on a base material. The base material is not particularly limited, and examples thereof include other thermoplastic resin base materials, thermosetting resin base materials, wood base materials, and non-wood fiber base materials. Examples of other thermoplastic resins used for the base material are the same as those described above as the material of the other layers constituting the laminated film. Other thermosetting resins used for the substrate include epoxy resins, phenolic resins, melamine resins and the like.
The manufacturing method of the laminated molded product is not particularly limited. For example, a laminated molded product can be obtained by subjecting the (laminated) film of the present invention to the above-mentioned substrate, if necessary, via an adhesive layer, vacuum forming, vacuum forming, compression molding, or the like under heating. can.
As another manufacturing method, the (laminated) film of the present invention is inserted between male and female molds for injection molding, and the molten thermoplastic resin is injected into one surface side of the (laminated) film in the mold. It is also preferable to use an injection-molded simultaneous bonding method in which the injection-molded body is formed and the injection-molded body and the (laminated) film are bonded at the same time. The (laminated) film of the present invention used in this method may be a flat film, or may be preformed by vacuum forming, pneumatic forming or the like and shaped into an arbitrary uneven shape. good. The (laminated) film of the present invention may be preformed in the mold of the injection molding machine used in the injection molding simultaneous bonding method, or may be performed using another molding machine. A method of pre-molding a (laminated) film and then injecting a molten resin onto one side thereof is called an insert molding method.
In the laminated molded product of the present invention, it is preferable that the layer made of the film of the present invention is the outermost layer. The laminated molded product of the present invention is excellent in surface smoothness, surface hardness, surface gloss and the like. When the laminated film of the present invention has a print layer, a pattern or the like is clearly displayed. Further, when a laminated film having a layer made of a metal or a metal oxide is used, a mirror surface gloss comparable to that of a metal can be obtained.

As described above, according to the present invention, it is possible to provide a methacrylic resin composition capable of obtaining a molded product having good high-temperature moldability and high dimensional stability with respect to heat. Since the methacrylic resin composition of the present invention has good moldability even when exposed to a higher temperature than before, even if it has a thermal history of, for example, about 280 ° C. when passing through a polymer filter, for example, it has a shape of a molded product. It can also handle complications. Further, the obtained molded product can have high dimensional stability even with heat of about 130 ° C.
According to the present invention, a methacrylic resin composition capable of obtaining a molded product having good high-temperature moldability, transparency, dimensional stability against heat, and mechanical strength (impact resistance, toughness, etc.). Can provide things.

Hereinafter, Examples and Comparative Examples according to the present invention will be described.
[Evaluation items and evaluation methods]
The evaluation items and evaluation methods are as follows.
(Polymerization conversion rate)
A gas chromatograph GC-14A manufactured by Shimadzu Corporation was used as a column on GL Sciences Inc. The Inert CAP 1 (df = 0.4 μm, ID = 0.25 mm, length = 60 m) was connected. The injection temperature was 180 ° C. and the detector temperature was 180 ° C. The column temperature was kept at 60 ° C. for 5 minutes, then raised from 60 ° C. to 200 ° C. at a heating rate of 10 ° C./min, and held at 200 ° C. for 10 minutes. Measurements were performed under these conditions, and the polymerization conversion rate was calculated based on the obtained results.

(Weight average molecular weight (Mw), molecular weight distribution (Mw / Mn))
A sample solution was prepared by dissolving 4 mg of the resin to be measured in 5 ml of tetrahydrofuran (THF) and filtering with a filter having a pore size of 0.1 μm. As the GPC device, "HLC-8320" manufactured by Tosoh Corporation equipped with a differential refractive index detector (RI detector) was used. As the column, two "TSKgel Super Multipore HZM-M" manufactured by Tosoh Corporation and "Super HZ4000" were connected in series. Tetrahydrofuran (THF) was used as the eluent. The temperature of the column oven was set to 40 ° C., the eluent flow rate was 0.35 ml / min, 20 μl of the sample solution was injected into the apparatus, and the chromatogram was measured. The chromatogram is a chart in which the electric signal value (intensity Y) derived from the difference in refractive index between the sample solution and the reference solution is plotted against the retention time X.
GPC measurement was performed using 10 points of standard polystyrene having a molecular weight in the range of 400 to 500000, and a calibration curve showing the relationship between the retention time and the molecular weight was prepared. Based on this calibration curve, Mw and Mw / Mn of the resin to be measured were determined. The chromatogram baseline is the point where the slope of the peak on the high molecular weight side of the GPC chart changes from zero to positive when viewed from the one with the earlier retention time, and the slope of the peak on the low molecular weight side is the one with the earlier retention time. It is a line connecting the points that change from minus to zero when viewed from. If the chromatogram shows multiple peaks, the line connecting the point where the slope of the peak on the highest molecular weight side changes from zero to plus and the point where the slope of the peak on the lowest molecular weight side changes from minus to zero. It was the baseline.

(Shinji Ikari City (rr) in triplet display)
^{1 1} H-NMR measurement was carried out for the resin to be measured. As a measuring device, a nuclear magnetic resonance device (“ULTRA SHIELD 400 PLUS” manufactured by Bruker) was used. 1 mL of deuterated chloroform was used as a deuterated solvent with respect to 10 mg of the sample. The measurement temperature was room temperature (20 to 25 ° C.), and the number of integrations was 64 times. The area (X) in the region of 0.6 to 0.95 ppm and the area (Y) in the region of 0.6 to 1.35 ppm when the reference substance (TMS) was set to 0 ppm were measured, and the formula: (X /). The value calculated by Y) × 100 was defined as the syndiotacticity (rr) (%) of the triplet display.

(Dynamic viscoelasticity measurement)
A strip-shaped test piece having a width of 5 mm was cut out from a heat press-molded film having a thickness of 1 mm, and dynamic viscoelasticity measurement was performed. As the measuring device, a forced vibration type dynamic viscoelasticity measuring device (“Rheogel-E4000” manufactured by UBM Co., Ltd.) was used. The test piece was set in the device with a distance between chucks of 20 mm. Fundamental frequency: 1Hz, measurement mode: tensile mode, strain control: 5 μm, strain waveform: sine wave, static load control: under automatic conditions, the temperature rise rate is increased from 50 ° C to 230 ° C at 3 ° C / min. , Temperature dependence was measured. The storage modulus (E'), loss modulus (E''), and tan δ were plotted, and the peak of tan δ appearing at 100 ° C to 180 ° C was defined as the α relaxation peak. The peak top temperature of this α relaxation was defined as the α relaxation temperature.

(Melt flow rate (MFR))
According to JIS K7210, the MFR of the resin to be measured was measured under the conditions of 230 ° C., 3.8 kg load and 10 minutes.
(Melting viscosity η)
After the resin to be measured was dried at 80 ° C. for 12 hours, the melt viscosity η was measured using “Capillograph 1D” manufactured by Toyo Seiki Co., Ltd. under the conditions of 260 ° C. and a shear rate of 122 sec ^-1 .

(High temperature moldability (thermogravimetric retention rate))
As a measuring device, a thermogravimetric measuring device (“TGA-50” manufactured by Shimadzu Corporation) was used. The thermogravimetric reduction of the resin to be measured was measured by a temperature profile in which the temperature was raised from 50 ° C. to 290 ° C. at a heating rate of 20 ° C./min and then held at 290 ° C. for 20 minutes in an air atmosphere. Using the weight at 50 ° C. as a reference (retention rate 100%), the weight retention rate after holding at 290 ° C. for 20 minutes was determined, and the high-temperature formability (heat-decomposability) was evaluated according to the following criteria. It can be said that the higher the thermogravimetric retention rate, the higher the heat-decomposability and the better the high-temperature moldability.
<Judgment criteria>
A (good): Thermal weight retention rate of 80% or more,
B (defective): Thermogravimetric retention rate is less than 80%.

(Haze)
The haze of the biaxially stretched film was measured using a haze meter (HM-150, manufactured by Murakami Color Research Institute) in accordance with JIS K7136.
(Total light transmittance)
The total light transmittance of the biaxially stretched film was measured using a haze meter (HM-150, manufactured by Murakami Color Research Institute) according to JIS K7361-1.

(Dimensional stability (coefficient of linear thermal expansion))
A test piece having a width of 4 mm, a length of 20 mm, and a thickness of 40 μm was cut out from the biaxially stretched film. As a measuring device, a thermomechanical analysis TMA (“Q400EM” manufactured by TA Instruments) was used. Under the conditions of a chuck distance of 8 mm and a load of 0.01 N, the temperature was raised from 25 ° C. to 130 ° C. at a heating rate of 10 ° C./min, and the amount of dimensional change of the test piece was measured. The coefficient of linear thermal expansion was calculated from the slope of the amount of dimensional change in the temperature range of 50 to 90 ° C.

(Impact resistance (impact resistance value))
A test piece having a size of 80 mm × 80 mm × thickness 40 μm was cut out from the biaxially stretched film. Using a film impact tester (manufactured by Yasuda Seiki Co., Ltd.), the impact resistance value when the test piece was broken by a sphere having a diameter of 12.7 ± 0.2 mmφ was measured.

(Phase difference in film thickness direction (Rth))
A 40 mm × 30 mm test piece was cut out from the obtained biaxially stretched film. This test piece was set in an automatic birefringence meter (“KOBRA-WR” manufactured by Oji Measurement Co., Ltd.). The phase difference in the 40 ° tilt direction was measured under the conditions of a temperature of 23 ± 2 ° C., a humidity of 50 ± 5%, and a wavelength of the measurement light of 590 nm. The refractive index n _x , n _y , n _z was calculated from this value and the average refractive index n, and the phase difference Rth (= ((n _x + n _y ) / 2-n _z ) × d) in the thickness direction was calculated. .. In addition, n _x is the refractive index in the in-plane slow phase axis direction, n _y is the refractive index in the in-plane slow phase axis orthogonal direction, n _z is the refractive index in the thickness direction, and d is the thickness [nm] of the test piece. be. The thickness d [nm] of the test piece was measured using a digital indicator (manufactured by Mitutoyo Co., Ltd.). The average refractive index n was measured using a digital precision refractometer (“KPR-20” manufactured by Carnew Optical Industry Co., Ltd.).

(Manufacturing Example 1) (Manufacturing of methacrylic resin (M1-1))
The inside of the autoclave equipped with the stirring blade and the three-way cock was replaced with nitrogen. To this, at room temperature, 1600 kg of toluene, 80 kg of 1,2-dimethoxyethane, and 73.3 kg of a toluene solution of isobutylbis (2,6-di-t-butyl-4-methylphenoxy) aluminum having a concentration of 0.45 M (2,6-di-t-butyl-4-methylphenoxy) ( 42.3 mol) and a solution of sec-butyllithium having a concentration of 1.3 M (solvent: cyclohexane 95% by mass / n-hexane 5% by mass) 8.44 kg (14.1 mmol) were charged. While stirring, 550 kg of distilled and purified MMA was added dropwise to this at 15 ° C. over 30 minutes. After completion of the dropping, the mixture was stirred at 15 ° C. for 90 minutes. The color of the solution changed from yellow to colorless. The polymerization conversion rate of MMA at this time was 100%. 1500 kg of toluene was added to the obtained solution to dilute it. The diluted solution was then poured into a large amount of methanol to give a precipitate. The obtained precipitate was dried at 80 ° C. and 140 Pa for 24 hours to obtain a methacrylic resin (M1-1).
The methacrylic resin (M1-1) has a Mw of 70,000, a melt viscosity η of 1200 Pa · s, a Mw / Mn of 1.06, a syndiotacticity (rr) of 75%, and an α relaxation temperature of 142 ° C. The content of the MMA monomer unit was 100% by mass (polymethyl methacrylate (PMMA)). Table 1 shows the physical characteristics of the methacrylic resin (M1-1).

(Manufacturing Example 2) (Manufacturing of methacrylic resin (M1-2))
The inside of the autoclave equipped with the stirring blade and the three-way cock was replaced with nitrogen. To this, at room temperature, 1600 kg of toluene, 60 kg of 1,2-dimethoxyethane, and 73.3 kg of a toluene solution of isobutylbis (2,6-di-t-butyl-4-methylphenoxy) aluminum having a concentration of 0.45 M (2,6-di-t-butyl-4-methylphenoxy) ( 42.3 mol) and a solution of sec-butyllithium having a concentration of 1.3 M (solvent: cyclohexane 95% by mass / n-hexane 5% by mass) 4.22 kg (7.1 mmol) were charged. While stirring, 550 kg of distilled and purified MMA was added dropwise to this at 15 ° C. over 30 minutes. After completion of the dropping, the mixture was stirred at 15 ° C. for 90 minutes. The color of the solution changed from yellow to colorless. The polymerization conversion rate of MMA at this time was 100%. 1500 kg of toluene was added to the obtained solution to dilute it. The diluted solution was then poured into a large amount of methanol to give a precipitate. The obtained precipitate was dried at 80 ° C. and 140 Pa for 24 hours to obtain a methacrylic resin (M1-2).
The methacrylic resin (M1-2) has a Mw of 36000, a melt viscosity η of 400 Pa · s, a Mw / Mn of 1.07, a syndiotacticity (rr) of 75%, and an α relaxation temperature of 138 ° C. The content of the MMA monomer unit was 100% by mass (polymethyl methacrylate (PMMA)). Table 1 shows the physical characteristics of the methacrylic resin (M1-2).

(Manufacturing Example 3) (Manufacturing of methacrylic resin (M2-1))
The inside of the autoclave equipped with a stirrer and a sampling tube was replaced with nitrogen. To this, 100 parts by mass of purified MMA, 0.0054 parts by mass of 2,2'-azobis (2-methylpropionitrile (hydrogen extraction capacity: 1%, 1 hour half-life temperature: 83 ° C.)), and n-octyl. 0.200 parts by mass of mercaptan was added and stirred to obtain a raw material solution. Nitrogen was sent into this raw material solution to remove dissolved oxygen.
The above raw material liquid was put into a tank reactor connected to the autoclave by a pipe up to 2/3 of the capacity. While the temperature was maintained at 140 ° C., the polymerization reaction was first started by a batch method. When the polymerization conversion rate reaches 55% by mass, the raw material liquid is supplied from the autoclave to the tank reactor at a flow rate with an average residence time of 150 minutes while maintaining the temperature at 140 ° C., and at the same time, it corresponds to the supply flow rate of the raw material liquid. The reaction solution was withdrawn from the tank reactor at the desired flow rate, and the polymerization reaction was switched to the continuous flow method. After switching, the polymerization conversion rate in the steady state was 48% by mass.
The reaction solution extracted from the tank-type reactor in a steady state was supplied to a multi-tube heat exchanger having an internal temperature of 230 ° C. at a flow rate having an average residence time of 2 minutes and heated. Then, the heated reaction solution was introduced into a flash evaporator, and the volatile matter containing the unreacted monomer as a main component was removed to obtain a molten resin. The molten resin from which the volatile components had been removed was supplied to a twin-screw extruder having an internal temperature of 260 ° C., discharged into a strand shape, and cut with a pelletizer to obtain a pellet-shaped methacrylic resin (M2-1).
The methacrylic resin (M2-1) has an Mw of 112000, a melt viscosity η of 1000 Pa · s, a Mw / Mn of 1.86, a syndiotacticity (rr) of 52%, and an α relaxation temperature of 129 ° C. The content of the MMA monomer unit was 100% by mass (polymethyl methacrylate (PMMA)). Table 1 shows the physical characteristics of the methacrylic resin (M2-1).

(Manufacturing Example 4) (Manufacturing of methacrylic resin (M2-2))
The inside of the autoclave equipped with a stirrer and a sampling tube was replaced with nitrogen. To this, 100 parts by mass of purified MMA, 0.0065 parts by mass of 2,2'-azobis (2-methylpropionitrile (hydrogen extraction capacity: 1%, 1 hour half-life temperature: 83 ° C.)), and n-octyl. 0.290 parts by mass of mercaptan was added and stirred to obtain a raw material solution. Nitrogen was sent into this raw material solution to remove dissolved oxygen.
The raw material liquid was put into a tank reactor connected to the autoclave by piping up to 2/3 of the capacity. First, the polymerization reaction was started by a batch method while maintaining the temperature at 120 ° C. When the polymerization conversion rate reaches 55% by mass, the raw material liquid is supplied from the autoclave to the tank reactor at a flow rate with an average residence time of 120 minutes while maintaining the temperature at 120 ° C., and at the same time, it corresponds to the supply flow rate of the raw material liquid. The reaction solution was withdrawn from the tank reactor at the desired flow rate, and the polymerization reaction was switched to the continuous flow method. After switching, the polymerization conversion rate in the steady state was 45% by mass.
The reaction solution extracted from the tank-type reactor in a steady state was supplied to a multi-tube heat exchanger having an internal temperature of 230 ° C. at a flow rate having an average residence time of 2 minutes and heated. Then, the heated reaction solution was introduced into a flash evaporator, and the volatile matter containing the unreacted monomer as a main component was removed to obtain a molten resin. The molten resin from which the volatile components had been removed was supplied to a twin-screw extruder having an internal temperature of 230 ° C., discharged in a strand shape, and cut with a pelletizer to obtain a pellet-shaped methacrylic resin (M2-2).
The methacrylic resin (M2-2) has an Mw of 83000, a melt viscosity η of 700 Pa · s, a Mw / Mn of 1.87, a syndiotacticity (rr) of 55%, and an α relaxation temperature of 130 ° C. The content of the MMA monomer unit was 100% by mass (polymethyl methacrylate (PMMA)). Table 1 shows the physical characteristics of the methacrylic resin (M2-2).

(Polycarbonate resin (PC))
The following polycarbonate resin (PC) was prepared.
(PC-1): Linear polycarbonate resin (measured under the conditions of "SD POLYCA TR-2201" manufactured by Sumika Stylon Polycarbonate Co., Ltd., MVR (based on JIS K7210, 300 ° C., load 1.2 kg, 10 minutes)) = 210 cm ^3/10 minutes, Mw = 22000, Mw / Mn = 2.0).

(Production Example 5) (Production of Crosslinked Rubber Particle Composition (CD-1))
<Manufacturing Example 5-1>
48 kg of ion-exchanged water was charged into a glass-lined 100 L reaction vessel equipped with a condenser, a thermometer, and a stirrer, and then 416 g of sodium stearate, 128 g of sodium lauryl sarcosinate, and 16 g of sodium carbonate were charged. And dissolved. Then, 11.2 kg of MMA and 110 g of allyl methacrylate were added, and the temperature was raised to 70 ° C. with stirring. Then, 560 g of a 2% potassium persulfate aqueous solution was added to initiate emulsion polymerization. The internal temperature rose due to the heat generated by the polymerization, and then the internal temperature began to fall. After the temperature was lowered to 70 ° C., the mixture was stirred at 70 ° C. for 30 minutes for emulsion polymerization to obtain an emulsion containing seed particles.
720 g of a 2% aqueous sodium persulfate solution was added to the emulsion containing the seed particles. Then, a mixture consisting of 12.4 kg of butyl acrylate, 1.76 kg of styrene, and 280 g of allyl methacrylate was added dropwise over 60 minutes. After completion of the dropping, the mixture was stirred for 60 minutes and subjected to emulsion polymerization to obtain an emulsion containing core-shell two-layer particles.
To the emulsion containing the core-shell two-layer particles, 320 g of a 2% aqueous potassium persulfate solution was added, and a mixture consisting of 6.2 kg of MMA, 0.2 kg of methyl acrylate, and 200 g of n-octyl mercaptan was added over 30 minutes. After the addition was completed, the mixture was stirred for 60 minutes for emulsion polymerization, and then cooled to room temperature. As described above, an emulsion containing 40% by mass of crosslinked rubber particles (acrylic three-layer polymer particles) (CR-1) having a core-shell three-layer structure having a volume-based average particle diameter of 0.23 μm was obtained.

<Manufacturing Example 5-2>
48 kg of ion-exchanged water is charged into a glass-lined 100 L reaction tank equipped with a condenser, a thermometer, and a stirrer, and then 252 g of a surfactant (Kao Corporation "Perex SS-H") is charged. And dissolved. After raising the temperature of the reaction vessel to 70 ° C., 160 g of a 2% potassium persulfate aqueous solution was added thereto, and then a mixture consisting of 3.04 kg of MMA, 0.16 kg of methyl acrylate, and 15.2 g of n-octyl mercaptan was collectively added. It was added to initiate emulsion polymerization. Stirring was continued for 30 minutes from the time when the heat generation due to the polymerization reaction disappeared.
After adding 160 g of a 2% potassium persulfate aqueous solution to this, a mixture consisting of 27.4 kg of MMA, 1.44 kg of methyl acrylate, and 98 g of n-octyl mercaptan was continuously added dropwise over 2 hours. After completion of the dropping, the mixture was stirred for 60 minutes to carry out emulsion polymerization. The resulting emulsion was cooled to room temperature. As described above, an emulsion containing 40% by mass of acrylic polymer particles (dispersion auxiliary particles) (DA-1) having a volume-based average particle size of 0.12 μm and an ultimate viscosity of 0.44 g / dl was obtained.

<Manufacturing example 5-3>
The emulsion containing the crosslinked rubber particles (acrylic three-layer polymer particles) (CR-1) obtained in Production Example 5-1 and the acrylic polymer particles (dispersion auxiliary particles) obtained in Production Example 5-2. ) (DA-1) was mixed so that the mass ratio of the particles (CR-1): particles (DA-1) was 2: 1. The mixed emulsion was frozen at −20 ° C. for 2 hours. The frozen mixed emulsion was put into twice the amount of warm water at 80 ° C. and thawed to obtain a slurry. The slurry was held at 80 ° C. for 20 minutes, then dehydrated, dried at 70 ° C. and pulverized. As described above, a crosslinked rubber particle composition (CD-1) containing crosslinked rubber particles (CR-1) and dispersion auxiliary particles (DA-1) was obtained.

(Production Example 6) (Production of Block Copolymer (BP-1))
In a three-necked flask whose inside was replaced with nitrogen, 735 kg of dry toluene, 36.75 kg of 1,2-dimethoxyethane and isobutylbis (2,6-di-t-butyl-) were placed at room temperature (20 to 25 ° C.). 4-Methylphenoxy) 20 mol of aluminum in a toluene solution was added with 39.4 kg. To this, 1.17 mol of sec-butyllithium was added. Further, 39.0 kg of MMA was added and reacted at room temperature for 1 hour to obtain an MMA polymer (methacrylic acid ester polymer) (b1-1). The Mw of the MMA polymer (b1-1) was 45,800.
Next, the reaction solution was cooled to −25 ° C., and a mixed solution of 29.0 kg of n-butyl acrylate and 10.0 kg of benzyl acrylate was added dropwise over 0.5 hours to obtain the MMA polymer (b1-1). The polymerization reaction was continued from the end of. Then, 4 kg of methanol was added to the reaction solution to stop the polymerization reaction, and the reaction solution was poured into a large amount of methanol to precipitate a block copolymer (BP-1). The obtained precipitate was filtered off and dried at 80 ° C. and 1 torr (about 133 Pa) for 12 hours.
As described above, a diblock copolymer composed of an MMA polymer block (b1-1) and an acrylic acid ester polymer block (b2-1) composed of n-butyl acrylate units and benzyl acrylate units (b2-1). BP-1) was obtained. The block copolymer (BP-1) had Mw of 92000 and Mw / Mn of 1.06. Since the Mw of the MMA polymer (b1-1) was 45800, the Mw of the acrylic acid ester polymer (b2-1) was determined to be 46200. The proportion of the benzyl acrylate unit in the acrylic acid ester polymer (b2-1) was 25.6% by mass. The mass ratio of (b1-1) / (b2-1) was 50/50.

(Ultraviolet absorber (LA))
The following ultraviolet absorbers (LA) were prepared.
(LA-31): 2,2'-methylenebis [6- (2H-benzotriazole-2-yl) -4-t-octylphenol] (manufactured by ADEKA),
(LA-F70): 2,4,6-tris (2-hydroxy-4-hexyloxy-3-methylphenyl) -1,3,5-triazine (manufactured by ADEKA).

(Polymer processing aid (PA))
The following polymer processing aids (PA) were prepared.
(PA-1): "Metabrene P550A" manufactured by Mitsubishi Rayon Co., Ltd. (average degree of polymerization: 7734, content of MMA monomer unit: 88% by mass, content of butyl acrylate monomer unit: 12% by mass).

(Example 1)
20 parts by mass of methacrylic resin (M1-1), 80 parts by mass of methacrylic resin (M2-1), 1.0 part by mass of block copolymer (BP-1), 0.9 parts by mass of ultraviolet absorber (LA-F70) , And 2 parts by mass of the polymer processing aid (PA-1), and melt-kneaded at 250 ° C. using a twin-screw extruder (“KZW20TW-45MG-NH-600” manufactured by Technobel Co., Ltd.). , The melt-kneaded product was extruded to produce a methacrylic resin composition (R11). The physical characteristics of the methacrylic resin composition (R11) were evaluated. Table 2 shows the composition and evaluation results of the methacrylic resin composition (R11).
The obtained methacrylic resin composition (R11) was dried at 80 ° C. for 12 hours. Using a 20 mmφ single-screw extruder (manufactured by OCS), the methacrylic resin composition (R11) is extruded from a T-die having a width of 150 mm at a resin temperature of 260 ° C. An unstretched film having a temperature of 160 μm was obtained.
The obtained unstretched film was cut out to a size of 100 mm × 100 mm. This film was subjected to biaxial stretching using a bitank batch biaxial stretching tester. Simultaneous biaxial stretching was carried out in the first tank under the conditions of stretching temperature Tg + 20 ° C., stretching speed 860% / min, stretching ratio 2 × 2, and then heat fixing temperature Tg-10 ° C. for 90 seconds in the second tank. After heat-fixing under the conditions, the film was rapidly cooled to obtain a biaxially stretched film (F11) having a thickness of 40 μm. Table 3 shows the stretching conditions and the evaluation results of the biaxially stretched film. Further, one side of the obtained biaxially stretched film (F11) was subjected to a corona discharge treatment, and then aluminum was vapor-deposited to a thickness of 30 nm by a vacuum vapor deposition method. The laminated film thus obtained had excellent mirror gloss.

(Examples 2 to 4)
In each of Examples 2 to 4, the methacrylic resin compositions (R12) to (R14) and the biaxially stretched films (F12) to (F14) are the same as in Example 1 except that the composition and stretching conditions are changed. ) Was obtained and evaluated. The composition, stretching conditions and evaluation results are shown in Tables 2 and 3.
(Comparative Examples 1 to 4)
In each of Comparative Examples 1 to 4, the methacrylic resin compositions (R21) to (R24) and the biaxially stretched films (F21) to (F24) were the same as in Example 1 except that the composition and stretching conditions were changed. ) Was obtained and evaluated. The composition, stretching conditions and evaluation results are shown in Tables 2 and 3.

(result)
In Examples 1 to 4, a methacrylic resin (M1) having an α relaxation temperature of 137 ° C. or higher and a methacrylic resin (M2) having an α relaxation temperature of 132 ° C. or lower are included, and the melt viscosity η of the methacrylic resin (M1) is contained. ₁ is larger than the melt viscosity η ₂ of the methacrylic resin (M2), and the mass ratio of the methacrylic resin (M1) / the methacrylic resin (M2) is 2/98 to 29/71. ) Was manufactured. All of the methacrylic resin compositions (R11) to (R14) obtained in Examples 1 to 4 had a high thermogravimetric retention rate and good high-temperature moldability. The biaxially stretched films (F11) to (F14) obtained in Examples 1 to 4 all had high transparency, a small coefficient of linear thermal expansion, good dimensional stability, and good impact resistance. ..

In Comparative Example 1 in which only the methacrylic resin (M2) was used as the methacrylic resin, the obtained biaxially stretched film (F21) had a large coefficient of linear thermal expansion, poor dimensional stability, and poor impact resistance. rice field. Although the methacrylic resin (M1) and the methacrylic resin (M2) were used in combination as the methacrylic resin, in Comparative Examples 2 and 3 in which the blending amount of the methacrylic resin (M1) was larger than that in Examples 1 to 3, the obtained methacrylic resin was obtained. All of the compositions (R22) to (R23) had a low heat weight retention rate and poor high-temperature moldability. In Comparative Example 4 in which the melt viscosity η ₁ of the methacrylic resin (M1) is smaller than the melt viscosity η ₂ of the methacrylic resin (M2), the coefficient of linear expansion is large, so that the dimensional stability is inferior and the impact resistance is also inferior.

The present invention is not limited to the above embodiments and examples, and the design can be appropriately changed as long as the gist of the present invention is not deviated.

This application claims priority on the basis of Japanese application Japanese Patent Application No. 2016-150205 filed on July 29, 2016 and incorporates all of its disclosures herein.

Claims (13)

A methacrylic resin having a weight average molecular weight of 40,000 to 200,000, a molecular weight distribution of 1.0 to 1.4, and an α relaxation temperature T _α1 of 137 ° C. or higher when measured in dynamic viscoelasticity in a tensile mode at 1 Hz. M1) and
It is a methacrylic resin composition with a methacrylic resin (M2) having a weight average molecular weight of 112000 to 200,000 and an α relaxation temperature T _α2 of 132 ° C. or lower when measured in a tensile mode and dynamic viscoelasticity at 1 Hz.
When the melt viscosities of the methacrylic resin (M1) and the methacrylic resin (M2) at 260 ° C. and a shear rate of 122 sec ^-1 are η ₁ and η ₂ , respectively, η ₁ > η ₂ .
A methacrylic resin composition having a mass ratio of methacrylic resin (M1) / methacrylic resin (M2) of 10/90 to 25/75. The methacrylic resin composition according to claim 1 , wherein the content of the methyl methacrylate monomer unit of the methacrylic resin (M2) is 99% by mass or more. The methacrylic resin composition according to claim 1 or 2 , further comprising a polycarbonate resin and / or a phenoxy resin. The methacrylic resin composition according to any one of claims 1 to 3 , further comprising a crosslinked rubber and / or a block copolymer. The methacrylic resin composition according to any one of claims 1 to 4 , further comprising an ultraviolet absorber. When the melt viscosities of the methacrylic resin (M1) and the methacrylic resin (M2) at 260 ° C. and a shear rate of 122 sec ^-1 are η ₁ and η ₂ , η ₁ > η ₂ .
A methacrylic resin having a weight average molecular weight of 40,000 to 200,000, a molecular weight distribution of 1.0 to 1.4, and an α relaxation temperature T _α1 of 137 ° C. or higher when measured in dynamic viscoelasticity in a tensile mode at 1 Hz. M1) and
A methacrylic resin (M2) having a weight average molecular weight of 112,000 to 200,000 and an α relaxation temperature T _α2 of 132 ° C. or lower when measured in a tensile mode and dynamic viscoelasticity at 1 Hz.
A method for producing a methacrylic resin composition, which is melt-kneaded at a mass ratio of methacrylic resin (M1) / methacrylic resin (M2) from 10/90 to 25/75. A molded product made of the methacrylic resin composition according to any one of claims 1 to 5 . A film comprising the methacrylic resin composition according to any one of claims 1 to 5 . The film according to claim 8 , which is a stretched film. A laminated film having a layer composed of the film according to claim 8 or 9 . The laminated film according to claim 10 , further comprising a layer composed of a metal and / or a metal oxide. The laminated film according to claim 10 or 11 , further comprising an adhesive layer. A laminated molded product in which the laminated film according to any one of claims 10 to 12 is laminated on a base material.