JP4329578B2 - Method for producing thermoplastic copolymer - Google Patents

Description

  The present invention relates to a method for producing a thermoplastic copolymer excellent in heat resistance and colorless transparency.

  Amorphous resins such as polymethyl methacrylate (hereinafter referred to as PMMA) and polycarbonate (hereinafter referred to as PC) make use of their transparency and dimensional stability to make various parts such as optical materials, household electrical appliances, office automation equipment and automobiles. Used in a wide range of fields.

  In recent years, these resins have been widely used in higher performance optical materials such as optical lenses, prisms, mirrors, optical disks, optical fibers, liquid crystal display sheets and films, light guide plates, etc. The optical properties, moldability, and heat resistance required for these products are also higher.

  At present, these transparent resins are also used as lamp members for automobiles such as tail lamps and head lamps, but in recent years, tail lamp lenses, inner lenses, There is a tendency to reduce the distance between various light sources such as headlamps and shield beams and the light source, and to reduce the thickness of the parts, and excellent moldability is required. Further, since the vehicle is used under severe conditions, it is required to have a small shape change under high temperature and high humidity, and excellent scratch resistance, weather resistance, and oil resistance.

  However, although PMMA resin has excellent transparency and weather resistance, there is a problem that heat resistance is not sufficient. On the other hand, PC resin is excellent in heat resistance and impact resistance, but has a large birefringence, which is an optical distortion, and has optical anisotropy in the molded product, remarkably in moldability, scratch resistance, and oil resistance. There was a problem of being inferior.

  Therefore, for the purpose of improving the heat resistance of PMMA, a resin in which a maleimide monomer or a maleic anhydride monomer is introduced as a heat resistance imparting component has been developed. However, maleimide monomers are expensive and have low reactivity, and maleic anhydride has a problem of poor thermal stability.

  As a method for improving the heat resistance of PMMA, a copolymer containing an unsaturated carboxylic acid monomer unit is heated using an extruder and cyclized to obtain a copolymer containing glutaric anhydride units. A polymer is disclosed (see, for example, Patent Document 1). However, when an ordinary extruder is used as the heat treatment apparatus disclosed in these patent documents, extreme shearing heat generation cannot be avoided, and the copolymer having glutaric anhydride units thus obtained is markedly colored. There was a problem. Further, in this method, the reaction time (residence time) in the extruder is short, the cyclization reaction cannot sufficiently proceed, and a large amount of unreacted unsaturated carboxylic acid monomer units remain. In addition, there are problems that silver or the like is generated during the heat forming process, or that the film is remarkably colored when heated.

  Further, as a method for solving these problems, a specific reaction accelerating catalyst is added when a copolymer containing an unsaturated carboxylic acid monomer unit is heated and cyclized by using an extruder. A method is disclosed (for example, see Patent Documents 2, 3, 4, and 5). However, in the methods disclosed in these patent documents, a reaction promoting catalyst such as a large amount of a basic inorganic compound is required to sufficiently advance the cyclization reaction, and coloring due to this is observed. Alternatively, the reaction promoting catalyst remaining in the polymer acts as a foreign substance, and there is a problem that high transparency cannot be obtained.

One technique for suppressing shear heat generation in an extruder is to use an extruder equipped with a single screw instead of a twin screw. Further, as one of methods for increasing the reaction time (residence time) in the extruder, there is a method using an extruder with a flow rate adjusting mechanism. For example, when manufacturing a filler-containing thermoplastic resin composition, a technique of using a kneading extruder composed of a biaxial kneading part having a flow rate adjusting mechanism and a single screw extrusion part as a kneading extruder is disclosed. (For example, refer to Patent Document 6). This patent document discloses that when a filler is contained in a thermoplastic resin at a high concentration, the productivity can be improved and the filler can be well dispersed. In this patent document, it is disclosed that the kneading extruder can adjust the residence time by a flow rate adjusting mechanism. However, in the production of a thermoplastic copolymer containing glutaric anhydride units, There is no disclosure that a kneading extruder having a simple structure can be used.
JP-A-49-85184 (page 1-2, Examples) JP-A-1-103612 (page 1-2, Examples) JP-A-61-254608 (page 1-2, Examples) JP 61-261303 A (page 1-2, Examples) JP-A-8-301931 (Page 1-2, Examples) JP 2002-79515 A (Page 1-2, Examples)

  Accordingly, an object of the present invention is to provide a process for producing a thermoplastic copolymer having high heat resistance and at the same time, high colorless transparency and residence stability that have been required in recent years.

  As a result of intensive studies to solve the above problems, the present inventors have been able to remarkably suppress coloring by using a reactor having a specific structure, and could not be achieved by conventional knowledge. We have found that it is possible to produce a thermoplastic copolymer that achieves a high degree of colorless transparency and is excellent in heat resistance and retention stability, and has reached the present invention.

That is, the present invention
[1] A raw copolymer (A) containing (i) an unsaturated carboxylic acid alkyl ester unit and (ii) an unsaturated carboxylic acid unit is heat-treated using a biaxial / uniaxial composite continuous kneading extruder. (Ii) Dehydration and / or (ii) Dealcoholization reaction to produce (iii) a glutaric anhydride unit-containing thermoplastic copolymer (B) represented by the following general formula (1) The biaxial / single-shaft combined continuous kneading and extruding apparatus comprises: a biaxial screw portion in which a first shaft and a second shaft forming a screw portion are arranged in parallel in a casing; A single screw portion in which a first shaft extended from the screw portion is disposed, and a flow rate adjusting mechanism is provided in a communicating portion between the biaxial screw portion and the single screw portion, and the biaxial screw portion is provided in the casing. With a material feed port that communicates And a method for producing a thermoplastic copolymer, characterized in that it is a biaxial / single-shaft composite continuous kneading extrusion apparatus having a discharge port communicating with the end of the extended first shaft,

(In the above formula, R ¹ and R ² are the same or different and represent any one selected from a hydrogen atom and an alkyl group having 1 to 5 carbon atoms.)
[2] The production according to the above [1], wherein the flow rate adjusting mechanism of the biaxial / single-shaft combined continuous kneading and extruding apparatus is a valve portion that connects the biaxial screw portion and the monoaxial screw portion. Method,
[3] The thermoplastic copolymer (B) is represented by the general formula (1) (iii) 25 to 50% by weight of a glutaric anhydride unit, and (i) an unsaturated carboxylic acid alkyl ester unit 50 to 75. The production method according to any one of the above [1] and [2], which is a copolymer having a weight percent,
[4] The method according to any one of [1] to [3] above, wherein the thermoplastic copolymer (B) has a glass transition temperature of 130 ° C. or higher.
[5] The production method according to any one of [1] to [4] above, wherein the (ii) unsaturated carboxylic acid unit has a structure represented by the following general formula (2):

(However, R ³ represents any one selected from hydrogen and an alkyl group having 1 to 5 carbon atoms)
[6] The production method according to any one of [1] to [5] above, wherein the (i) unsaturated carboxylic acid alkyl ester unit has a structure represented by the following general formula (3):

(However, R ⁴ represents any one selected from hydrogen and an alkyl group having 1 to ⁵ carbon atoms, and R ⁵ is an aliphatic or alicyclic hydrocarbon group having 1 to 6 carbon atoms or one or more carbon atoms. A C1-C6 aliphatic or alicyclic hydrocarbon group substituted with a number of hydroxyl groups or halogens)
[7] The production method as described in any one of [1] to [6] above, wherein the original copolymer (A) is obtained at a polymerization temperature of 95 ° C. or lower.

  By the production method of the present invention, a thermoplastic polymer having high heat resistance and high colorless transparency can be obtained.

  Hereafter, the manufacturing method of the thermoplastic copolymer (B) of this invention is demonstrated concretely.

  First, as described above, the thermoplastic copolymer (B) of the present invention is represented by the following general formula (1).

(In the above formula, R ¹ and R ² are the same or different and represent any one selected from a hydrogen atom and an alkyl group having 1 to 5 carbon atoms.)
It is a thermoplastic copolymer containing the glutaric anhydride unit represented by these. Above all, a copolymer having (iii) a glutaric anhydride unit represented by the general formula (1) and (i) an unsaturated carboxylic acid alkyl ester unit, or a copolymer having (ii) an unsaturated carboxylic acid unit in the above unit. A polymer or a copolymer having (iv) other vinyl monomer units in addition to the units (i), (iii) or (i), (ii), (iii) is preferred.

  Such a thermoplastic copolymer (B) containing a glutaric anhydride unit represented by the above general formula (1) of the present invention can be basically produced by the method shown below. it can. That is, (iii) an unsaturated carboxylic acid monomer and an unsaturated carboxylic acid alkyl ester monomer that give a glutaric anhydride unit represented by the general formula (1) by the subsequent heating step, and (iv) When other vinyl monomer units are included, the copolymer is copolymerized with a vinyl monomer that gives the units to form an original copolymer (A), and then the original copolymer (A) is converted into an appropriate copolymer. It can be produced by heating in the presence or absence of a catalyst to carry out an intramolecular cyclization reaction by (i) dealcoholization and / or (b) dehydration. In this case, typically, the original copolymer (A) is heated to dehydrate from the carboxyl group of two units (ii) unsaturated carboxylic acid units, or adjacent (ii) unsaturated carboxylic acid. Alcohol is eliminated from the unit and (i) the unsaturated carboxylic acid alkyl ester unit to produce one unit of the above (iii) glutaric anhydride unit.

  There is no restriction | limiting in particular as an unsaturated carboxylic acid monomer used in this case, Any unsaturated carboxylic acid monomer which can be copolymerized with another vinyl compound can be used. As a preferable unsaturated carboxylic acid monomer, the following general formula (4)

(However, R ³ represents any one selected from hydrogen and an alkyl group having 1 to 5 carbon atoms)
In particular, acrylic acid and methacrylic acid are preferred, and methacrylic acid is more preferred from the viewpoint of excellent thermal stability. These can be used alone or in combination. In addition, the unsaturated carboxylic acid monomer represented by the general formula (4) gives an unsaturated carboxylic acid unit having a structure represented by the general formula (2) when copolymerized.

  Moreover, there is no restriction | limiting in particular as an unsaturated carboxylic-acid alkylester type monomer, However, As a preferable example, what is represented by following General formula (5) can be mentioned.

(However, R ⁴ represents any one selected from hydrogen and an alkyl group having 1 to ⁵ carbon atoms, and R ⁵ is an aliphatic or alicyclic hydrocarbon group having 1 to 6 carbon atoms or one or more carbon atoms. A C1-C6 aliphatic or alicyclic hydrocarbon group substituted with a number of hydroxyl groups or halogens)

  Among these, an acrylate ester and / or a methacrylic ester having an aliphatic or alicyclic hydrocarbon group having 1 to 6 carbon atoms or the hydrocarbon group having a substituent is particularly preferable. The unsaturated carboxylic acid alkyl ester monomer represented by the general formula (5) gives an unsaturated carboxylic acid alkyl ester unit having a structure represented by the general formula (3) when copolymerized.

  Preferable specific examples of the unsaturated carboxylic acid alkyl ester monomer include methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, n-butyl (meth) acrylate, (meth ) T-butyl acrylate, n-hexyl (meth) acrylate, cyclohexyl (meth) acrylate, chloromethyl (meth) acrylate, 2-chloroethyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate , (Meth) acrylic acid 3-hydroxypropyl, (meth) acrylic acid 2,3,4,5,6-pentahydroxyhexyl and (meth) acrylic acid 2,3,4,5-tetrahydroxypentyl Of these, methyl methacrylate is most preferably used. These can be used alone or in combination of two or more thereof.

  In the production of the original copolymer (A) used in the present invention, (iv) other vinyl monomers may be used as long as the effects of the present invention are not impaired. (Iv) Preferred specific examples of other vinyl monomers include styrene, α-methylstyrene, o-methylstyrene, p-methylstyrene, o-ethylstyrene, p-ethylstyrene and pt-butylstyrene. Aromatic vinyl monomers such as, vinyl cyanide monomers such as acrylonitrile, methacrylonitrile, ethacrylonitrile, allyl glycidyl ether, styrene-p-glycidyl ether, p-glycidyl styrene, maleic anhydride, anhydrous Itaconic acid, N-methylmaleimide, N-ethylmaleimide, N-cyclohexylmaleimide, N-phenylmaleimide, acrylamide, methacrylamide, N-methylacrylamide, butoxymethylacrylamide, N-propylmethacrylamide, aminoethyl acrylate, acrylic Propylaminoethyl acrylate, glycidyl acrylate, dimethylaminoethyl methacrylate, ethylaminopropyl methacrylate, phenylaminoethyl methacrylate, cyclohexylaminoethyl methacrylate, glycidyl methacrylate, N-vinyldiethylamine, N-acetylvinylamine, allylamine , Methallylamine, N-methylallylamine, p-aminostyrene, 2-isopropenyl-oxazoline, 2-vinyl-oxazoline, 2-acryloyl-oxazoline, 2-styryl-oxazoline, and the like. A monomer that does not contain an aromatic ring is more preferable. These may be used alone or in combination of two or more.

  As for the polymerization method of the original copolymer (A), basically known polymerization methods such as bulk polymerization, solution polymerization, suspension polymerization, emulsion polymerization, etc. by radical polymerization can be used, but there are fewer impurities. Particularly preferred are solution polymerization, bulk polymerization and suspension polymerization.

  The polymerization temperature is not particularly limited, but from the viewpoint of color tone, a monomer mixture containing an unsaturated carboxylic acid monomer and an unsaturated carboxylic acid alkyl ester monomer is polymerized at a polymerization temperature of 95 ° C. or less. It is preferable. Furthermore, in order to further suppress the coloration after the heat treatment, a preferable polymerization temperature is 85 ° C. or less, and particularly preferably 75 ° C. or less. The lower limit of the polymerization temperature is not particularly limited as long as the polymerization proceeds, but is usually 50 ° C. or higher, preferably 60 ° C. or higher from the viewpoint of productivity considering the polymerization rate. The polymerization time is not particularly limited as long as it is a sufficient time to obtain the required degree of polymerization, but is preferably in the range of 60 to 360 minutes, particularly preferably in the range of 90 to 180 minutes from the viewpoint of production efficiency.

  In the present invention, the preferred proportion of these monomer mixtures used in the production of the original copolymer (A) is such that the monomer mixture is 100% by weight and the unsaturated carboxylic acid monomer is 15 to 50%. % By weight, more preferably 20-45% by weight, unsaturated carboxylic acid alkyl ester monomer is preferably 50-85% by weight, more preferably 55-80% by weight, other vinyl-based copolymerizable with these When using a monomer, the preferable ratio is 0 to 35 weight%, and 0 to 10 weight% is especially preferable.

  When the amount of the unsaturated carboxylic acid monomer is less than 15% by weight, the amount of (iii) glutaric anhydride unit represented by the above general formula (1) by heating the original copolymer (A) Tend to be less. On the other hand, when the amount of the unsaturated carboxylic acid monomer exceeds 50% by weight, a large amount of (ii) unsaturated carboxylic acid unit tends to remain after the cyclization reaction by heating the original copolymer (A). There is a tendency for colorless transparency and retention stability to decrease.

  Moreover, it is preferable that the weight average molecular weight of the thermoplastic copolymer (B) excellent in colorless transparency and residence stability of the present invention is a specific 50,000 to 150,000. The thermoplastic copolymer (B) having such a molecular weight is obtained by changing the original copolymer (A) to a desired molecular weight, that is, a weight average molecular weight of 50,000 to 150,000 during the production of the original copolymer (A). This can be achieved by controlling in advance. When the weight average molecular weight exceeds 150,000, there is a tendency to color at the time of heat degassing in the subsequent step. On the other hand, when the weight average molecular weight is less than 50,000, the mechanical strength of the molded product tends to decrease. The thermoplastic copolymer (B) of the present invention is more preferably 70,000 to 130,000, still more preferably 80,000 to 110,000. In addition, the weight average molecular weight as used in the field of this invention shows the weight average molecular weight in the absolute molecular weight measured by multi-angle light scattering gel permeation chromatography (GPC-MALLS).

  There is no restriction | limiting in particular about the molecular weight control method of an original copolymer (A), For example, a conventionally well-known technique is applicable. For example, controlled by the amount of radical polymerization initiators such as azo compounds and peroxides, or the amount of chain transfer agents such as alkyl mercaptans, carbon tetrachloride, carbon tetrabromide, dimethylacetamide, dimethylformamide, triethylamine, etc. can do. In particular, a method of controlling the amount of alkyl mercaptan added as a chain transfer agent can be preferably used from the viewpoint of stability of polymerization, ease of handling, and the like.

  Examples of the alkyl mercaptan used in the present invention include n-octyl mercaptan, t-dodecyl mercaptan, n-dodecyl mercaptan, n-tetradecyl mercaptan, n-octadecyl mercaptan and the like. Among them, t-dodecyl mercaptan, n-dodecyl mercaptan is preferably used.

  The addition amount of these alkyl mercaptans is not particularly limited as long as it is controlled to a specific molecular weight of the present invention, but the lower limit of the addition amount is usually 0 with respect to 100% by weight of the total amount of the monomer mixture. 0.2, 0.3, 0.4, 0.8, 0.9, and 1.0% by weight are preferable in this order, and the upper limit is preferably 5.0, 4.0, and 3.0% by weight in this order.

  In the present invention, the original copolymer (A) is heated using a biaxial / uniaxial composite continuous kneading extrusion apparatus, and (i) dehydration and / or (b) dealcoholization reaction is performed by dealcoholization, A thermoplastic copolymer (B) containing a glutaric anhydride unit is produced. As the biaxial / single-screw composite continuous extrusion device, a first shaft and a second shaft having a screw part formed in a casing are provided. A biaxial screw portion arranged in parallel, and a monoaxial screw portion arranged with a first shaft extended from the biaxial screw portion, and a flow rate at a communicating portion between the biaxial screw portion and the monoaxial screw portion A biaxial / single-shaft composite continuous kneading extrusion apparatus comprising an adjustment mechanism, and having a raw material supply port communicating with the biaxial screw portion in the casing and a discharge port communicating with the end portion of the extended first shaft Characterized by using equipment .

  FIG. 1 is a schematic cross-sectional view of a plane of the above-described biaxial / single-axis composite continuous kneading and extruding apparatus, and the casing 1 is entirely formed in a cylindrical shape. Further, in the casing 1, a biaxial screw portion 5 in which the first shaft 2 and the second shaft 3 are arranged in parallel, and a single shaft screw portion 6 including an extension shaft portion 4 of the first shaft are formed. . A raw material supply port 7 that communicates with the biaxial screw portion 5 is formed in the vicinity of the base end portions of the first shaft 2 and the second shaft 3 in the casing 1. On the other hand, a discharge port 8 is provided on the distal end side of the extension shaft portion 4 in the casing 1. Further, in the casing 1, it is preferable that a deaeration port 9 is formed on the base end side of the extension shaft portion 4.

  Moreover, it is preferable that the valve | bulb part 10 is provided in the casing 1 in the base end part side of the said extension shaft part 4 of the said biaxial / single-axis composite type continuous kneading extrusion apparatus of this invention as a flow control mechanism. . The valve unit 10 has a valve body (not shown) that can move forward and backward in the direction of the arrow H, and can bypass the molten resin from the biaxial screw unit 5 to the single screw unit 6 to adjust the flow rate. It is possible.

  Further, the biaxial screw portion of the biaxial / uniaxial composite type continuous kneading extruder used in the present invention is rotating in a different direction, and is non-meshing type, which suppresses shearing heat generation in the biaxial screw portion. This is preferable.

  As the biaxial / single-axis composite continuous kneading and extruding apparatus, for example, “HTM50” and “HTM38” manufactured by CTE can be preferably used.

  Moreover, it is more preferable that the apparatus has a structure in which an inert gas such as nitrogen can be introduced into the biaxial / uniaxial composite continuous kneading and extruding apparatus. For example, as a method of introducing an inert gas such as nitrogen, a method of connecting a pipe of an inert gas stream of about 1 to 100 liters / minute from the upper part and / or the lower part of the hopper can be mentioned.

  The temperature at which the original copolymer (A) of the present invention is heated to produce the thermoplastic copolymer (B) is such that (i) dehydration and / or (b) dealcoholization reaction is caused by dealcoholization. The lower limit is preferably 180 ° C., more preferably 190 ° C., further preferably 200 ° C., and the upper limit is preferably 320 ° C., more preferably 315 ° C., more preferably 310 ° C. More preferably, it is 300 degreeC, More preferably, it is 290 degreeC.

  In addition, the time for the heat treatment at this time is not particularly limited, and can be appropriately set according to the desired copolymer composition. Usually, it is 3 minutes to 60 minutes, preferably 5 minutes to 30 minutes, especially 8 to 20 minutes. A range of minutes is preferred.

   The screw rotation speed of the specific biaxial / single-screw combined continuous extrusion apparatus used in the present invention is preferably as small as possible from the viewpoint of colorless transparency which is the effect of the present invention. The screw rotation number when using the above-mentioned CTE “HTM50 (cylinder diameter 50 mm)” is preferably 10 to 100 rpm, more preferably 20 to 90 rpm, and particularly preferably 30 to 80 rpm. Further, the screw rotation speed when using the above-mentioned CTE “HTM38 (cylinder diameter 38 mm)” is preferably 30 to 200 rpm, more preferably 40 to 190 rpm, and particularly preferably 50 to 180 rpm.

  It has been found that the thermoplastic copolymer (B) obtained by using a specific biaxial / uniaxial composite continuous kneading extrusion apparatus used in the present invention is extremely excellent in colorless transparency. (Ii) When the raw copolymer (A) having an unsaturated carboxylic acid unit is heated in a continuous manner to advance the cyclization reaction, the extrusion viscosity is increased due to the increase in melt viscosity as the reaction proceeds. There is a tendency for heat generation due to shearing to increase and coloring due to thermal decomposition to increase. Further, the shear heat generation becomes larger when melt kneading with a twin screw than with a single screw. On the other hand, from the viewpoint of reaction rate, it is preferable to melt and knead with a twin screw. From the above, by using the twin-screw / single-screw composite continuous kneading extrusion apparatus of the present invention, in the initial reaction stage where the melt viscosity is relatively low, the twin-screw is used to melt while securing a sufficient reaction rate. In the later stage of the reaction where the viscosity is relatively high, the thermoplastic copolymer (B) containing glutaric anhydride units that are excellent in color tone by heat treatment with a single screw part that suppresses shearing heat generation. Is presumed to have been obtained.

  Furthermore, since the biaxial / single-shaft combined continuous kneading extrusion apparatus used in the present invention is provided with a flow rate adjusting valve part, it is easy to arbitrarily set the heat treatment time, so that sufficient cyclization reaction can be achieved. Progress (cyclization reaction rate) can be achieved.

  Furthermore, in this invention, when heating original copolymer (A) by the said method etc., 1 or more types of an acid, an alkali, and a salt compound are added as a catalyst which accelerates | stimulates the cyclization reaction to glutaric anhydride. Can do. The addition amount is suitably less than 0.1 parts by weight with respect to 100 parts by weight of the original copolymer (A), but since there is a tendency to remain in the thermoplastic copolymer (B) as foreign matter, It is preferable to reduce the addition amount as much as possible. There are no particular restrictions on the types of these acids, alkalis, and salt compounds, and examples of the acid catalyst include hydrochloric acid, sulfuric acid, p-toluenesulfonic acid, phosphoric acid, phosphorous acid, phenylphosphonic acid, and methyl phosphate. It is done. Examples of the basic catalyst include metal hydroxides, amines, imines, alkali metal derivatives, alkoxides, ammonium hydroxide salts and the like. Furthermore, examples of the salt-based catalyst include metal acetates, metal stearates, metal carbonates, and the like. However, it is necessary to add in a range where the color possessed by the catalyst does not adversely affect the coloring of the thermoplastic copolymer (B) and the transparency is not lowered. Among them, the compound containing an alkali metal can be preferably used because it exhibits an excellent reaction promoting effect with a relatively small addition amount. Specifically, hydroxides such as lithium hydroxide, sodium hydroxide, and potassium hydroxide, alkoxide compounds such as sodium methoxide, sodium ethoxide, sodium phenoxide, potassium methoxide, potassium ethoxide, and potassium phenoxide, lithium acetate And organic carboxylates such as sodium acetate, potassium acetate and sodium stearate, among which sodium hydroxide, sodium methoxide, lithium acetate and sodium acetate can be preferably used.

  The content of the (iii) glutaric anhydride unit represented by the general formula (1) in the thermoplastic copolymer (B) produced according to the present invention is not particularly limited, but is preferably a thermoplastic copolymer. It is 25-50 weight% in 100 weight% of polymers (B), More preferably, it is 30-45 weight%.

  In addition, as the thermoplastic copolymer (B) produced in the present invention, it is preferable to use a copolymer having the above (iii) glutaric anhydride unit and (i) an unsaturated carboxylic acid alkyl ester unit. it can. (I) The unsaturated carboxylic acid alkyl ester unit amount is preferably 50 to 75% by weight, more preferably 55 to 70% by weight in 100% by weight of the thermoplastic copolymer (B).

Further, the quantification of each component unit in the thermoplastic copolymer produced by the present invention (B) is an infrared spectrophotometer or a proton nuclear magnetic resonance ⁽¹ H-NMR) measuring machine can be used. In infrared spectroscopy, glutaric anhydride units, absorption of 1800 cm ^-1 and 1760 cm ^-1 are characteristic can be distinguished from unsaturated carboxylic acid units and unsaturated carboxylic acid alkyl ester unit. In the ¹ H-NMR method, for example, in the case of a copolymer consisting of glutaric anhydride, methacrylic acid, and methyl methacrylate, the spectral assignment in dimethyl sulfoxide heavy solvent is 0.5 to 1.5 ppm. The peak is methacrylic acid, methyl methacrylate and α-methyl group hydrogen of glutaric anhydride ring compound, the peak of 1.6 to 2.1 ppm is hydrogen of the methylene group of the polymer main chain, and the peak of 3.5 ppm is methacrylic acid The hydrogen of methyl carboxylic acid ester (—COOCH ₃ ), the peak at 12.4 ppm can determine the copolymer composition from the hydrogen of carboxylic acid of methacrylic acid and the integral ratio of the spectrum. In addition to the above, in the case of a copolymer containing styrene as another copolymer component, hydrogen of an aromatic ring of styrene is seen at 6.5 to 7.5 ppm, and the copolymer is similarly obtained from the spectral ratio. The composition can be determined.

  The amount of (ii) unsaturated carboxylic acid unit contained in the thermoplastic copolymer (B) produced in the present invention is preferably 0 to 5% by weight, more preferably 0 to 1% by weight. . (Ii) When the unsaturated carboxylic acid unit exceeds 5% by weight, the colorless transparency and the residence stability tend to decrease.

  Further, more preferable copolymerizable (iv) amount of other vinyl monomer units is preferably 0 to 35% by weight, particularly preferably 0 to 10% by weight. In particular, when an aromatic vinyl monomer unit such as styrene is contained, if the content exceeds the above range, colorless transparency tends to decrease.

  Moreover, it is preferable in terms of heat resistance that the thermoplastic copolymer (B) of the present invention has a glass transition temperature (Tg) of 130 ° C. or higher. In a more preferred embodiment, it has an excellent heat resistance of 140 ° C. or higher, and in a particularly preferred embodiment, 150 ° C. or higher. Moreover, as an upper limit, it is about 170 degreeC normally. The glass transition temperature here is a glass transition temperature (Tg) measured at a temperature rising rate of 20 ° C./min in a nitrogen stream using a differential scanning calorimeter (DSC-7 manufactured by Perkin Elmer). It is.

  In addition, the thermoplastic copolymer (B) obtained by the production method of the present invention has a molded product with a greatly improved color tone, and a molded product having a yellowness (Yellowness Index) value of 3 or less. It is done. Further, in a preferred embodiment, it has a very excellent colorlessness of 2 or less, and in a most preferred embodiment, 1 or less. Here, the yellowness index is a SM color computer (in accordance with JIS-K7103), a 3 mm-thick molded product obtained by injection molding at a glass transition temperature of + 140 ° C. of the thermoplastic copolymer (B). YI value measured using Suga Test Instruments Co., Ltd.

  Further, the thermoplastic copolymer (B) of the present invention includes hindered phenol-based, benzotriazole-based, benzophenone-based, benzoate-based, and cyanoacrylate-based UV absorbers and antioxidants, higher fatty acids and acid ester-based compounds. And acid amides, lubricants and plasticizers such as higher alcohols, montanic acid and salts thereof, esters thereof, half esters thereof, release agents such as stearyl alcohol, stearamide and ethylene wax, phosphites, hypophosphorous acid Anti-coloring agents such as salts, halogen-based flame retardants, phosphorus-based and silicone-based non-halogen-based flame retardants, nucleating agents, amine-based, sulfonic acid-based, polyether-based anti-static agents, pigments and other colorants You may contain an additive arbitrarily. However, it is necessary to add in a range where the color of the additive does not adversely affect the thermoplastic copolymer and the transparency is not lowered.

  The thermoplastic copolymer (B) of the present invention is excellent in mechanical properties and molding processability, and can be melt-molded. Therefore, extrusion molding, injection molding, press molding, etc. are possible. Film, sheet It can be used after being molded into a tube, a rod or a molded product having any desired shape and size.

  And the molded article of the thermoplastic copolymer (B) of the present invention makes use of its excellent heat resistance, and housings such as electric / electronic parts, automobile parts, mechanical mechanism parts, OA equipment, home appliances and their It can be used for various applications such as parts and general goods.

  Specific uses of the molded article comprising the thermoplastic copolymer (B) of the present invention include, for example, electrical equipment housings, OA equipment housings, various covers, various gears, various cases, sensors, LED lamps, connectors, Socket, resistor, relay case, switch, coil bobbin, capacitor, variable capacitor case, optical pickup, oscillator, various terminal boards, transformer, plug, printed wiring board, tuner, speaker, microphone, headphones, small motor, magnetic head base , Power modules, housings, semiconductors, LCDs, FDD carriages, FDD chassis, motor brush holders, parabolic antennas, computer-related parts and other electrical and electronic parts; VTR parts, TV parts, irons, hair dryers, rice cookers Products, microwave oven parts, acoustic parts, audio equipment parts such as audio / laser discs / compact discs, lighting parts, refrigerator parts, air conditioner parts, typewriter parts, word processor parts, etc. Computer-related parts, telephone-related parts, facsimile-related parts, copier-related parts, cleaning jigs, oilless bearings, stern bearings, underwater bearings and other various bearings, motor parts, lighters, typewriters, and other machines Related parts, microscopes, binoculars, cameras, optical equipment represented by watches, precision machine parts; alternator terminals, alternator connectors, IC regulators, exhaust gas valves and other valves, fuel-related / exhaust system / intake system pipes, Air intake Snorkel, intake manifold, fuel pump, engine coolant joint, carburetor main body, carburetor spacer, exhaust gas sensor, coolant sensor, oil temperature sensor, brake pad wear sensor, throttle position sensor, crankshaft position sensor, air flow meter , Thermostat base for air conditioner, Heating hot air flow control valve, Brush holder for radiator motor, Water pump impeller, Turbine vane, Wiper motor related parts, Dust distributor, starter switch, starter relay, transmission wire harness, window washer nozzle , Air conditioner panel switch board, coil for fuel related solenoid valve, connector for fuse Motor, horn terminal, electrical component insulation plate, step motor rotor, lamp socket, lamp reflector, lamp housing, brake piston, solenoid bobbin, engine oil filter, and ignition device case. In addition, because of its excellent transparency and heat resistance, various video equipment-related parts such as camera, VTR, projection TV and other shooting lenses, viewfinders, filters, prisms, Fresnel lenses, etc. Information equipment related parts such as optical disk (VD, CD, DVD, MD, LD, etc.) substrates, various disk substrate protective films, optical disk player pickup lenses, optical fibers, optical switches, optical connectors, etc., liquid crystal displays, flat panel displays, plasma displays Light guide plate, Fresnel lens, polarizing plate, polarizing plate protective film, retardation film, light diffusion film, viewing angle widening film, reflection film, antireflection film, antiglare film, brightness enhancement film, prism sheet, pickup lens, tapping As light guide film for panels, covers, etc., parts related to transportation equipment such as automobiles, tail lamp lens, head lamp lens, inner lens, amber cap, reflector, extension, side mirror, rear mirror, side visor, instrument needle, instrument cover, window Glass parts such as glazing typified by glass, eyeglass lenses, eyeglass frames, contact lenses, endoscopes, optical cells for analysis, etc., lighting parts, road translucent plates, lighting covers, signs, etc. It is extremely useful for these various uses such as a translucent sound insulation wall and a bathtub material.

  Hereinafter, the configuration and effects of the present invention will be described more specifically with reference to examples. However, the present invention is not limited to the following examples. Prior to the description of each example, various physical property measurement methods employed in the example will be described.

(1) Weight average molecular weight (absolute molecular weight)
Gel permeation chromatograph (pump: model 515, manufactured by Waters, column: TSK-gel-GMH _XL , Tosoh) equipped with a DAWN-DSP type multi-angle light scattering photometer (manufactured by Wyatt Technology) using dimethylformamide as a solvent Was used, and the weight average molecular weight (absolute molecular weight) was measured.

(2) Glass transition temperature (Tg)
Using a differential scanning calorimeter (DSC-7 manufactured by Perkin Elmer), the measurement was performed at a temperature increase rate of 20 ° C./min in a nitrogen atmosphere.

(3) Yellowness Index
SM color computer (manufactured by Suga Test Instruments Co., Ltd.) according to JIS-K7103, the YI value of a molded product of thickness 70 mm × 70 mm × 3 mm obtained by injection molding of the obtained thermoplastic copolymer at a glass transition temperature + 140 ° C. It measured using.

(4) Transparency (total light transmittance, haze)
Using a direct reading haze meter manufactured by Toyo Seiki Co., Ltd., the total light transmittance at 23 ° C. of a molded product of 70 mm × 70 mm × 3 mm obtained by injection molding of a thermoplastic copolymer at a glass transition temperature of + 140 ° C. (% ) And haze (cloudiness) (%) were measured to evaluate transparency.

(5) Stability of Stabilization In a cylinder of an injection molding machine, after retaining for 20 minutes at a glass transition temperature + 140 ° C., the presence or absence of bubbles in a molded product of 70 mm × 70 mm × 3 mm obtained by injection molding was visually observed.

Production of raw copolymer (A) (A-1)
In a stainless steel autoclave having a capacity of 20 liters and equipped with a baffle and a foudra-type stirring blade, a methyl methacrylate / acrylamide copolymer suspension (prepared by the following method: 20 parts by weight of methyl methacrylate, 80 parts by weight of acrylamide) Then, 0.3 parts by weight of potassium persulfate and 1500 parts by weight of ion-exchanged water are charged into the reactor, and the reactor is replaced with nitrogen gas and maintained at 70 ° C. The reaction completely converts the monomer into a polymer. Then, a solution in which 0.05 part of the resulting aqueous solution was used as a suspending agent was dissolved in 165 parts of ion-exchanged water and stirred at 380 rpm. The inside of the system was replaced with nitrogen gas. Next, the following mixed substances were added while stirring the reaction system, and the temperature was raised to 70 ° C. The time when the internal temperature reached 70 ° C. was set as the start of polymerization, and kept for 110 minutes to complete the polymerization. Thereafter, the reaction system was cooled, the polymer was centrifuged, washed with water, and dried in accordance with ordinary methods to obtain a bead-shaped original copolymer (A-1). The polymerization rate of this original copolymer (A-1) was 95%, and the weight average molecular weight was 110,000.
Methacrylic acid 30 parts by weight Methyl methacrylate 70 parts by weight t-dodecyl mercaptan 1.2 parts by weight 2,2′-azobisisobutyronitrile 0.4 parts by weight

(A-2)
After maintaining the polymerization temperature and time at 70 ° C. for 20 minutes, the temperature was increased to 90 ° C., and the raw copolymer (A -2) was obtained at a polymerization rate of 98%, and the weight average molecular weight was 110,000.

(A-3)
The raw copolymer (A-3) was obtained at a polymerization rate of 95% by the same production method as (A-1) except that the charged composition of the monomer mixture and chain transfer agent was changed to the following, and the weight average molecular weight was obtained. Was 100,000.
Methacrylic acid 15 parts by weight Methyl methacrylate 75 parts by weight Styrene 10 parts by weight t-dodecyl mercaptan 0.8 parts by weight

Examples 1-5, Comparative Examples 1-5
In this embodiment, HTM50 (cylinder diameter 50 mm, L / D = 46, manufactured by CTE) or HTM38 (cylinder diameter 38 mm, L / D), which is a biaxial / single-shaft composite continuous kneading extruder equipped with a flow control valve. = 48, manufactured by CTE). Various raw copolymers (A) obtained above, or the additives shown in Table 1 were blended, and nitrogen was blown from the hopper port at a rate of 10 L / min. (HTM50) or 10 kg / h (HTM38) continuously supplied, screw rotation: 40 rpm (HTM50) or 75 rpm (HTM38), cylinder temperature: 285 ° C (HTM50) or 305 ° C (HTM38), heat treatment (cyclization) Reaction). At this time, the flow rate adjusting valve is appropriately adjusted, and the residence time (the time from when the raw copolymer (A) as a raw material is charged through the hopper to the time when it is discharged) is 11 minutes (HTM50) or 9 minutes ( HTM38). The screw in the biaxial / single-shaft continuous kneading and extruding apparatus is one that rotates in a non-meshing different direction.

  In addition, as a comparison, the heat treatment was performed using a twin screw extruder TEX44α (manufactured by Nippon Steel) with an L / D of 44.5 while blowing nitrogen at an amount of 10 L / min from the hopper port. Continuously supplying to the extruder at 20 kg / h, heat treatment (cyclization reaction) was performed at a screw rotation speed of 40 rpm and a cylinder temperature of 280 ° C. At this time, the residence time (the time from when the raw copolymer (A), which is a raw material, was charged from the hopper part to when it was discharged) was 5 minutes. In the above twin screw extruder, the screw is a mesh type and rotates in the same direction.

Next, the pellets dried at 100 ° C. for 3 hours were subjected to an injection molding machine (M-50AII-SJ manufactured by Meiki Seisakusho Co., Ltd.) to mold each test piece. Molding conditions are molding temperature: glass transition temperature + 140 ° C., mold temperature: 80 ° C., injection speed: 90 cm ³ / sec, injection time: 10 seconds, cooling time: 30 seconds, molding pressure: all the resin is filled in the mold Pressure (molding lower limit pressure) +1 MPa.

  Table 1 shows each copolymer component composition and various characteristics evaluation results determined by 1H-NMR.

  From the results of Examples 1 to 5 and Comparative Examples 1 to 5, (iii) heat having a glutaric anhydride structural unit obtained by using the specific biaxial / uniaxial composite continuous kneading extruder of the present invention It can be seen that the plastic copolymer (B) is excellent in heat resistance and has high colorless transparency and retention stability.

On the other hand, when a normal twin-screw extruder is used, more unreacted unsaturated carboxylic acid (methacrylic acid) units tend to remain, and the cyclization reaction proceeds again due to retention in the molding machine. This is considered to be due to the fact that bubbles are observed in the molded product. Moreover, in order to eliminate this problem, it is necessary to add a large amount of a basic inorganic compound (NaOCH ₃ ), which increases the haze of the molded product, and it is understood that high transparency cannot be obtained.

  The molded article of the thermoplastic copolymer obtained by the method of the present invention, utilizing its excellent heat resistance, is a housing for electric / electronic parts, automobile parts, mechanical mechanism parts, OA equipment, home appliances, etc. and those parts. It can be used for various applications such as general goods and general goods.

It is the schematic of the cross section which shows an example of the biaxial single-axis composite type continuous kneading extrusion apparatus used by this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Casing 2 ... 1st axis | shaft 3 ... 2nd axis | shaft 4 ... Extension shaft part 5 ... Biaxial screw part 6 ... Single axis screw part 7 ... Raw material supply port 8 ... Discharge port 9 ... Deaeration port 10 ... Flow control valve

Claims (7)

The raw copolymer (A) containing (i) an unsaturated carboxylic acid alkyl ester unit and (ii) an unsaturated carboxylic acid unit is heat-treated using a biaxial / uniaxial composite continuous kneading extruder, (Iii) A method of producing a thermoplastic copolymer (B) containing a glutaric anhydride unit represented by the following general formula (1) by performing dehydration and / or (b) dealcoholization reaction. The biaxial / single-shaft continuous kneading and extruding device includes a biaxial screw portion in which a first shaft and a second shaft that form a screw portion are arranged in parallel in a casing, and a biaxial screw portion. A raw material having a single screw portion in which the extended first shaft is disposed, and having a flow rate adjusting mechanism in a communication portion between the biaxial screw portion and the single screw portion, and communicating with the biaxial screw portion in the casing With a supply port, A method for producing a thermoplastic copolymer, comprising: a biaxial / single-shaft composite continuous kneading and extruding apparatus having a discharge port communicating with an end of the extended first shaft.

(In the above formula, R ¹ and R ² are the same or different and represent any one selected from a hydrogen atom and an alkyl group having 1 to 5 carbon atoms.) 2. The manufacturing method according to claim 1, wherein the flow rate adjusting mechanism of the biaxial / single-shaft composite continuous kneading and extruding apparatus is a valve portion that communicates the biaxial screw portion and the monoaxial screw portion. The thermoplastic copolymer (B) is represented by the general formula (1) (iii) glutaric anhydride unit 25 to 50% by weight, (i) unsaturated carboxylic acid alkyl ester unit 50 to 75% by weight. The production method according to claim 1, wherein the production method is a copolymer. The glass transition temperature of a thermoplastic copolymer (B) is 130 degreeC or more, The manufacturing method in any one of Claims 1-3 characterized by the above-mentioned. The production method according to any one of claims 1 to 4, wherein the (ii) unsaturated carboxylic acid unit has a structure represented by the following general formula (2).

(However, R ³ represents any one selected from hydrogen and an alkyl group having 1 to 5 carbon atoms) The production method according to any one of claims 1 to 5, wherein the (i) unsaturated carboxylic acid alkyl ester unit has a structure represented by the following general formula (3).

(However, R ⁴ represents any one selected from hydrogen and an alkyl group having 1 to ⁵ carbon atoms, and R ⁵ is an aliphatic or alicyclic hydrocarbon group having 1 to 6 carbon atoms or one or more carbon atoms. A C1-C6 aliphatic or alicyclic hydrocarbon group substituted with a number of hydroxyl groups or halogens) The said copolymer (A) is obtained at the polymerization temperature of 95 degrees C or less, The manufacturing method in any one of Claims 1-6 characterized by the above-mentioned.

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