JP2001031833A - Transparent thermoplastic resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject composition having good color tone and excellent in physical property balance between impact resistance and stiffness by adding a specific graft copolymer to a (co)polymer melted during continuous mass polymerization of a vinyl monomer mixture in a specific proportion followed by mixing the blend. SOLUTION: This composition is obtained by adding (A) 10 to 95 pts.wt. of a (co)polymer melted during continuous mass polymerization of at least one kind of a vinyl-based monomer mixture to (B) 90 to 5 pts.wt. of a graft copolymer produced by subjecting (ii) at least one kind of a vinyl-based monomer mixture to graft polymerization in the presence of (i) a rubbery polymer, followed by mixing the blend. It is desirable that the vinyl-based monomer mixture in the component A comprises 5-70 wt.% of an aromatic vinyl monomer and 30 to 95 wt.% of an unsaturated carboxylic(acid)alkyl ester-based monomer, while the component ii comprises 5 to 70 wt.% of an aromatic vinyl-based monomer and 30 to 95 wt.% of an unsaturated carboxylic(acid)alkyl ester-based monomer.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermoplastic resin composition having excellent color tone and excellent balance between physical properties such as impact resistance and rigidity.

[0002]

2. Description of the Related Art A transparent polymer obtained by graft copolymerization of a vinyl polymer such as vinyl cyanide such as acrylonitrile or methacrylonitrile or an aromatic vinyl such as styrene or α-methylstyrene onto a rubbery polymer such as a diene rubber. Thermoplastic resin composition having impact resistance, moldability, appearance,
It is excellent in transparency and the like, and is widely used for applications such as OA equipment, home appliances, and general goods.

[0003] It is known that such a transparent thermoplastic resin can be obtained by making the refractive indices of the rubber component and the matrix resin close to each other.

In general, a rubber-reinforced styrene-based thermoplastic resin needs to be graft-polymerized to a rubber component in order to exhibit sufficient mechanical properties, and emulsion graft polymerization has been conventionally used as a production method. However, the emulsion polymerization method has a problem that the cost is increased due to the large number of steps and the number of auxiliary materials, and that wastewater treatment is required. Therefore, in order to reduce the problem of the emulsion polymerization, a method of melt-blending a rubber-free polymer obtained by an emulsion graft-polymerized high rubber-containing polymer and a suspension polymerization method, a continuous bulk polymerization method, or the like is known. (ABS resin, edited by the Society of Polymer Science, Japan). This method is applied to the production of a thermoplastic resin having transparency, and a high rubber-containing polymer obtained by emulsion graft polymerization and a matrix resin substantially matching the rubber component and the refractive index are separately produced and melt-blended. Methods are generally known.

However, a method in which a high rubber-containing polymer obtained by emulsion graft polymerization and a rubber-free polymer obtained by a suspension polymerization method or a continuous bulk polymerization method are obtained as isolated polymers, respectively, and then melt-blended. Has the advantage of being able to control the physical properties relatively smoothly, but has the drawback that the color tone is not sufficient due to further heat history during melt blending, and the physical properties balance between impact resistance and rigidity is not sufficient. On the other hand, the method of directly manufacturing a thermoplastic resin containing rubber by a continuous bulk polymerization method is the most excellent in that the number of steps and auxiliary materials is small and that wastewater treatment is unnecessary, but control of the graft polymerization reaction in the bulk polymerization. And the rubber component receives more heat history, resulting in poor color tone. Furthermore, it is not always satisfactory in terms of physical properties such as impact resistance. Further, when the rubber component is increased, there is a disadvantage in that a deteriorated product of the rubber stays in the apparatus or the rubber is peeled off, which causes a problem in production and quality.

[0006]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a thermoplastic resin which solves the above-mentioned drawbacks of the prior art and has excellent color tone and excellent balance between physical properties of impact resistance and rigidity. Is to do.

[0007]

Means for Solving the Problems As a means for solving such problems, as a result of intensive studies on a thermoplastic resin composition having transparency, a thermoplastic resin composition obtained from a vinyl monomer by a specific method was obtained. It has been found that when a graft polymer is added to a polymer by a specific method and mixed, a thermoplastic resin composition having excellent transparency, such as excellent color balance and physical properties of impact resistance and rigidity, can be obtained. Reached the present invention.

[0008] That is, the present invention relates to a method for producing a mixture of one or more vinyl-based monomers (a) in a continuous bulk polymerization, in which 10 to 95 parts by weight of a (co) polymer (A) in a molten state is used. 90 to 5 parts by weight of a graft copolymer (B) obtained by graft polymerization of at least one vinyl monomer mixture (c) in the presence of the rubbery polymer (b) is added and mixed. A thermoplastic resin composition having transparency "
It is.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION The transparent thermoplastic resin composition of the present invention is a (co) polymer in a molten state during a process of continuously bulk polymerizing one or more kinds of a vinyl monomer mixture (a). (A) Graft copolymer (B) 90 obtained by graft-polymerizing one or more vinyl monomer mixtures (c) in the presence of rubbery polymer (b) with respect to 10 to 95 parts by weight. -5 parts by weight are added and mixed.

The composition of the at least one vinyl monomer mixture (a) constituting the (co) polymer (A) is not particularly limited, but the transparency of the resulting thermoplastic resin having transparency is not critical. Therefore, it is preferable to adjust the composition of the vinyl monomer mixture (a) so that the refractive index of the (co) polymer (A) substantially matches that of the rubbery polymer (b). As a specific range, the difference in the refractive index between the (co) polymer (A) and the rubbery polymer (b) is preferably suppressed to 0.03 or less, more preferably 0.01 or less.

The monomer component constituting the vinyl-based monomer mixture (a) is not particularly limited, but from the viewpoint of a balance between physical properties of impact resistance and rigidity, aromatic vinyl-based monomers (ma1) 5 to 5 are used.
70% by weight, vinyl cyanide monomer (ma2) 0-3
5% by weight, 30 to 95% by weight of an unsaturated carboxylic acid alkyl ester monomer (ma3) and 0 to 50% by weight of another monomer (ma4) copolymerizable therewith, more preferably. Is an aromatic vinyl monomer (m
a1) 5 to 55% by weight of a vinyl cyanide monomer (ma
2) 0 to 25% by weight, 45 to 95% by weight of an unsaturated carboxylic acid alkyl ester monomer (ma3) and 0 to 40% by weight of another monomer (ma4) copolymerizable therewith.

The aromatic vinyl monomer (ma1) in the vinyl monomer mixture (a) includes styrene, α-
Examples include methylstyrene, p-methylstyrene, vinyltoluene, t-butylstyrene, o-ethylstyrene, o-chlorostyrene, o, p-dichlorostyrene and the like, with styrene and α-methylstyrene being particularly preferred. One or more of these can be used.

Examples of the vinyl cyanide monomer (ma2) include acrylonitrile, methacrylonitrile, ethacrylonitrile and the like, and acrylonitrile is particularly preferred. One or more of these can be used.

As the unsaturated carboxylic acid alkyl ester monomer (ma3), methyl (meth) acrylate,
Ethyl (meth) acrylate, n-propyl (meth) acrylate, n-butyl (meth) acrylate, t-butyl (meth) acrylate, n-hexyl (meth) acrylate,
Cyclohexyl (meth) acrylate, glycidyl (meth) acrylate, hydroxyethyl (meth) acrylate,
Examples thereof include chloromethyl (meth) acrylate and 2-chloroethyl (meth) acrylate, with methyl methacrylate being particularly preferred. One or more of these can be used.

Further, other monomers (ma4) include N
-Methylmaleimide, N-cyclohexylmaleimide,
Maleimide compounds such as N-phenylmaleimide; unsaturated carboxylic acids such as acrylic acid and methacrylic acid; unsaturated dicarboxylic acids such as maleic acid; unsaturated dicarboxylic anhydrides such as maleic anhydride; and unsaturated amides such as acrylamide. Is mentioned.

The intrinsic viscosity of the (co) polymer (A) in the present invention is not particularly limited, but is preferably 0.05 to 1.2 dl / g from the viewpoint of a balance between impact resistance and moldability. .15 to 0.8 dl / g is more preferred.

The (co) polymer (A) in the present invention can be used alone or in combination of two or more. When a blend of two or more is used, each component is dispersed optically uniformly. It is preferable from the viewpoint of the transparency of the obtained thermoplastic resin that the refractive index of the (co) polymer (A) as a whole is substantially adjusted to the rubbery polymer (b).

In the present invention, the continuous bulk polymerization method in the step of obtaining the (co) polymer (A) by subjecting the vinyl monomer mixture (a) to continuous bulk polymerization is not particularly limited.
Any continuous bulk polymerization method can be employed. For example,
There is known a method of removing monomers (devolatilization) after polymerization in a polymerization tank. As the polymerization tank, various types of stirring blades, for example, a paddle blade, a turbine blade, a propeller blade, a bulmar blade, a multistage blade, an anchor blade, a max blend blade, a double helical blade, a mixed type polymerization tank having a A tower type reactor or the like can be used. Furthermore, a multi-tube reactor, a kneader-type reactor, a twin-screw extruder, or the like can also be used as a polymerization reactor (for example, assessment of polymer production process 10 “Assessment of impact-resistant polystyrene”: Society of Polymer Science, Japan) , January 26, 1989). These polymerization tanks (reactors) are used in one (tank) or in two or more (tanks), and if necessary, two or more kinds of reactors may be used in combination.

The reaction mixture of the (co) polymer (A) polymerized in these polymerization tanks or reactors is usually then subjected to a demonomerization step to remove monomers and other volatile components. As a method of demonomerization, a single-screw or twin-screw extruder with a vent is used to remove volatile components from the vent hole under heating at normal pressure or reduced pressure, and a plate fin type heater such as a centrifugal type is built in a drum and evaporated. A method of removing volatile components with a heat exchanger, a method of removing volatile components with a thin-film evaporator such as a centrifugal type, a method of removing residual components by using a multi-tube heat exchanger, preheating, bubbling and flashing into a vacuum tank There are
Although any method can be used, a single-screw or twin-screw extruder having a vent is particularly preferably used.

In the continuous bulk polymerization of the (co) polymer (A), thermal polymerization without using an initiator, initiator polymerization using an initiator, and thermal polymerization and initiator polymerization can be performed. It is also possible to use them together. As the initiator, a peroxide or an azo compound is used.

Specific examples of the peroxide include benzoyl peroxide, cumene hydroperoxide, dicumyl peroxide, diisopropylbenzene hydroperoxide, t-butyl hydroperoxide, t-butyl hydroperoxide and t-butyl hydroperoxide.
-Butylcumyl peroxide, t-butylperoxyacetate, t-butylperoxybenzoate, t-
Butyl peroxyisopropyl carbonate, di-t-
Butyl peroxide, t-butyl peroctate,
1,1-bis (t-butylperoxy) 3,3,5-trimethylcyclohexane, 1,1-bis (t-butylperoxy) cyclohexane, t-butylperoxy-2
-Ethylhexanoate and the like. Among them, cumene hydroperoxide and 1,1-bis (t-
Butylperoxy) 3,3,5-trimethylcyclohexane is particularly preferably used. Specific examples of the azo compound include azobisisobutyronitrile and azobis (2,
4-dimethylvaleronitrile), 2-phenylazo-2,
4-dimethyl-4-methoxyvaleronitrile, 2-cyano-2-propylazoformamide, 1,1'-azobiscyclohexane-1-carbonitrile, azobis (4
-Methoxy-2,4-dimethylvaleronitrile), dimethyl 2,2'-azobisisobutyrate, 1-tert-butylazo-1-cyanocyclohexane, 2-tert-butylazo-2-cyanobutane, 2-tert-butylazo -2-cyano-4-methoxy-4-methylpentane and the like. When using these initiators, one type or two or more types are used in combination. Among them, 1,1'-azobiscyclohexane-1-carbonitrile is particularly preferably used.

For the purpose of controlling the degree of polymerization of the (co) polymer (A) used in the present invention, a chain transfer agent such as mercaptan or terpene may be used. Specific examples thereof include n-octyl mercaptan and t-dodecyl mercaptan, n-dodecyl mercaptan, n-tetradecyl mercaptan, n-octadecyl mercaptan, terpinolene, and the like. When these chain transfer agents are used, one type or two or more types are used in combination. Among them, n-octyl mercaptan, t-dodecyl mercaptan and n-dodecyl mercaptan are particularly preferably used.

The (co) polymer (A) used in the present invention is produced by a continuous bulk polymerization method.
% Or less) can be used for polymerization,
It is included in the scope of the present invention.

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

The weight average particle diameter of the rubbery polymer (b) is from 0.1 to 1.5 μm in view of the impact resistance, moldability, flowability and appearance of the thermoplastic resin composition obtained. Preferably, more preferably 0.15 to 1.2 μm
It is.

The composition of one or more kinds of the vinyl monomer mixture (c) constituting the graft component of the graft copolymer (B) is not particularly limited, but the transparency of the obtained thermoplastic resin having transparency is not limited. In view of the above, the refractive index of the graft component (d) of the graft copolymer (B) is substantially equal to that of the rubbery polymer (b).
It is preferable to adjust the composition of the vinyl monomer mixture (c) so as to conform to the above. As a specific range, it is preferable that the difference in the refractive index between the graft component (d) and the rubbery polymer (b) is suppressed to 0.03 or less, more preferably 0.01 or less.

The monomer component constituting the vinyl monomer mixture (c) is not particularly limited, but is preferably an aromatic vinyl monomer (mc1) 5 to 5 in view of a balance between physical properties of impact resistance and rigidity.
70% by weight, vinyl cyanide monomer (mc2) 0-3
5% by weight, 30 to 95% by weight of an unsaturated carboxylic acid alkyl ester monomer (mc3) and 0 to 50% by weight of another monomer (mc4) copolymerizable therewith, more preferably. Is an aromatic vinyl monomer (m
c1) 5 to 55% by weight of a vinyl cyanide monomer (mc
2) 0 to 25% by weight, 45 to 95% by weight of an unsaturated carboxylic acid alkyl ester monomer (mc3) and 0 to 40% by weight of another monomer (mc4) copolymerizable therewith. The monomer composition constituting the vinyl monomer mixture (c) may be the same as or different from the vinyl monomer mixture (a) constituting the (co) polymer (A).

As the aromatic vinyl monomer (mc1) in the vinyl monomer mixture (c), styrene, α-
Examples include methylstyrene, p-methylstyrene, vinyltoluene, t-butylstyrene, o-ethylstyrene, o-chlorostyrene, o, p-dichlorostyrene and the like, with styrene and α-methylstyrene being particularly preferred. One or more of these can be used.

Examples of the vinyl cyanide monomer (mc2) include acrylonitrile, methacrylonitrile, ethacrylonitrile and the like, and acrylonitrile is particularly preferred. One or more of these can be used.

As the unsaturated carboxylic acid alkyl ester monomer (mc3), methyl (meth) acrylate,
Ethyl (meth) acrylate, n-propyl (meth) acrylate, n-butyl (meth) acrylate, t-butyl (meth) acrylate, n-hexyl (meth) acrylate,
Cyclohexyl (meth) acrylate, glycidyl (meth) acrylate, hydroxyethyl (meth) acrylate,
Examples thereof include chloromethyl (meth) acrylate and 2-chloroethyl (meth) acrylate, with methyl methacrylate being particularly preferred. One or more of these can be used.

Further, other monomers (mc4) include N
-Methylmaleimide, N-cyclohexylmaleimide,
Maleimide compounds such as N-phenylmaleimide; unsaturated carboxylic acids such as acrylic acid and methacrylic acid; unsaturated dicarboxylic acids such as maleic acid; unsaturated dicarboxylic anhydrides such as maleic anhydride; and unsaturated amides such as acrylamide. Is mentioned.

The graft copolymer (B) in the present invention may be used alone or in combination of two or more. When a blend of two or more is used, the rubbery polymer (b) contained in each component is used. ) And the graft component (d) are preferably prepared from the viewpoint of the transparency of the thermoplastic resin obtained so that the refractive indices thereof substantially match.

The intrinsic viscosity of the graft component (d) constituting the graft copolymer (B) in the present invention is not particularly limited, but 0.05 to 1.2 dl / g is a balance between impact resistance and moldability. From the point of view, it is more preferable that the range is 0.1 to 0.1.
7 dl / g is more preferred.

The graft copolymer (B) in the present invention
Is obtained by graft-polymerizing at least one vinyl monomer mixture (c) in the presence of a rubbery polymer (b), and the entire amount of the vinyl monomer mixture (c) is grafted. It is not necessary to use the one obtained usually as a mixture with an ungrafted (co) polymer. Although the graft ratio of the graft copolymer (B) is not limited, it is preferably 5 to 150% by weight, more preferably 1 to 150% by weight from the viewpoint of impact resistance.
Those having 0 to 100% by weight are used.

The proportion of the rubbery polymer in the graft copolymer (B) is 5 to 80 parts by weight, more preferably 20 to 80 parts by weight, from the viewpoint of the mechanical strength, color tone and moldability of the obtained resin composition. 70 parts by weight.

The method for producing the graft copolymer (B) is not limited, but is preferably produced by an emulsion polymerization method or a bulk polymerization method. Above all, it is most preferable that the rubber component is produced by an emulsion polymerization method from the viewpoint of suppressing deterioration of the rubber component due to excessive heat history and coloring. Emulsion polymerization usually involves emulsion graft polymerization of a monomer mixture in the presence of a rubbery polymer latex. There is no particular limitation on the emulsifier used for this emulsion graft polymerization, and various surfactants can be used.
Anionic surfactants such as carboxylate type, sulfate type and sulfonate type are particularly preferably used.
Specific examples of such emulsifiers include caprylate, caprate, laurate, mystyrate, palmitate, stearate, oleate, linoleate, linolenate, rosinate, Behenate, castor oil sulfate, lauryl alcohol sulfate,
Other higher alcohol sulfates, dodecylbenzene sulfonate, alkyl naphthalene sulfonate, alkyl diphenyl ether disulfonate, naphthalene sulfonate condensate, dialkyl sulfosuccinate,
Polyoxyethylene lauryl sulfate, polyoxyethylene alkyl ether sulfate, polyoxyethylene alkyl phenyl ether sulfate and the like can be mentioned. The salt here refers to an alkali metal salt, an ammonium salt, and the like,
Specific examples of the alkali metal salt include a potassium salt, a sodium salt, and a lithium salt. These emulsifiers are used alone or in combination of two or more.

The initiators and chain transfer agents usable in these emulsion graft polymerizations include the initiators and chain transfer agents mentioned in the production of the (co) polymer (A), and the initiator is redox. Also used in systems.

The graft copolymer (B) produced by the emulsion graft polymerization is then added with a coagulant to coagulate the latex to recover the graft copolymer (B). Acid or water-soluble salt is used as a coagulant, and as a specific example,
Sulfuric acid, hydrochloric acid, phosphoric acid, acetic acid, calcium chloride, magnesium chloride, barium chloride, aluminum chloride, magnesium sulfate, aluminum sulfate, aluminum ammonium sulfate, aluminum potassium sulfate, aluminum sodium sulfate, and the like. These coagulants are used in one kind or in a mixture of two or more kinds. The coagulated graft copolymer (B) is preferably dehydrated and dried in advance, and added to the (co) polymer (A) in a molten state from the viewpoint of handleability in the process.

As described above, the graft copolymer (B)
Can also be produced by a bulk polymerization method. In the case of production by the bulk polymerization method, the graft copolymer (B) in a molten state that has come out of the demonomerizer can be directly added to the (co) polymer (A), or it can be simply added in advance. Although it is possible to add the separated graft copolymer (B) to the (co) polymer (A), the graft copolymer (B) is usually in a molten state coming out of the demonomerizer from the viewpoint of preventing thermal deterioration and continuation of the process. It is more preferable to directly add the graft copolymer (B).

In the present invention, it is necessary to add the graft copolymer (B) to the (co) polymer (A) in the molten state during the bulk polymerization process and then to mix them, which makes it possible to obtain color and impact resistance for the first time. An excellent resin composition such as At that time, the (co) polymer (A) 10 to 9 in a molten state
It is necessary to add 90 to 5 parts by weight of the graft copolymer (B) to 5 parts by weight, more preferably 30 to 95 parts by weight of the (co) polymer (A) to 7 to 7 parts by weight of the graft copolymer (B).
After adding 0 to 5 parts by weight, mix. The addition of the graft copolymer (B) is preferably performed continuously. At this time, the addition of the graft copolymer (B) is such that the residual monomer amount is 10% or less, more preferably 5% during or after the demonomerization step of the bulk polymerization process of the (co) polymer (A). When performed at the following points, the rubber component does not deteriorate due to heat history during the subsequent demonomerization operation,
The color tone, impact resistance, and the like, which are the characteristics of the present invention, are further improved. In the present invention, (co)
The mixing after the addition of the graft copolymer (B) to the polymer (A) is preferably performed by melt mixing in order to sufficiently exhibit physical properties such as impact resistance. This melt mixing may be performed at the time of addition mixing or after isolation of the mixture, for example, at the time of melt molding.

The method for adding the graft copolymer (B) is not particularly limited, and the graft copolymer (B) can be added by any method. Usually, it is continuously added using various feeders, for example, a belt type feeder, a screw type feeder, a single screw extruder, a twin screw extruder, etc., but it is added to the (mono) polymer (A) demonomer extruder. A connected single screw extruder and twin screw extruder are particularly preferably used. It is preferable that these continuous addition devices can measure a quantity. Further, the continuous addition device has a heating device, and it is preferable to add the graft copolymer (B) in a semi-molten or molten state because the mixing state is improved. For this purpose, an extruder having a heating device can be used.

In the thermoplastic resin composition of the present invention, polyolefins such as vinyl chloride, polyethylene and polypropylene, polyamides such as nylon 6 and nylon 66, polyethylene terephthalate, and the like, as long as the object of the present invention is not impaired.
The performance as a molding resin can be improved by adding a polyester such as polybutylene terephthalate and polycyclohexanedimethyl terephthalate, a polycarbonate, and various elastomers. In addition, if necessary, an antioxidant such as a hindered phenol type, a sulfur-containing organic compound type, a phosphorus-containing organic compound type, a heat stabilizer such as a phenol type or an acrylate type, a benzotriazole type, a benzophenone type, a salicylate type, etc. Various stabilizers such as ultraviolet absorbers, light stabilizers such as organic nickel-based and hindered amine-based,
Lubricants such as metal salts of higher fatty acids, higher fatty acid amides,
Plasticizers such as phthalates and phosphates; halogen-containing compounds such as polybromodiphenyl ether, tetrabromobisphenol-A, brominated epoxy oligomers and brominated polycarbonate oligomers; phosphorus-based compounds; and difficulties such as antimony trioxide. Flame retardants / flame retardants, antistatic agents, carbon black, titanium oxide, pigments and dyes can also be added. Further, reinforcing agents and fillers such as glass fibers, glass flakes, glass beads, carbon fibers, and metal fibers can also be added. The method of adding these additives is not particularly limited, and they can be continuously added together with the graft copolymer (B), and are added as a subsequent step after isolating the mixture of (A) and (B). Various methods can be used.

The present invention will be described more specifically with reference to examples and comparative examples, but these examples do not limit the present invention. Unless otherwise specified, “%” indicates% by weight and “parts” indicates “parts by weight”. A method for analyzing the resin characteristics of the thermoplastic resin composition will be described below. For general properties such as impact resistance and tensile strength, test pieces were molded by injection molding and measured according to the following test methods. (1) Weight average rubber particle diameter “Rubber Age Vol.88 p.484-
490 (1960) by E.I. Schmidt, P .;
H. Sodium alginate method described in "Biddison" (using the fact that the particle size of polybutadiene to be creamed varies depending on the concentration of sodium alginate, the particles having a cumulative weight fraction of 50% from the cumulative weight fraction of the creamed weight ratio and the sodium alginate concentration) Find the diameter). (2) Graft rate A predetermined amount of the graft copolymer (m; about 1 g) was added to acetone 20.
0 ml was added and the mixture was refluxed for 3 hours in a 70 ° C. water bath. p. m. After centrifugation at (10000 G) for 40 minutes, the insoluble matter was filtered, and the insoluble matter was removed at 60 ° C. for 5 minutes.
After drying under reduced pressure for a time, the weight (n) was measured. The graft ratio was calculated from the following equation. Here, L is the rubber content of the graft copolymer. Graft rate (%) = ｛[(n) − (m) × L] /
[(M) × L]｝ × 100 (3) Reduced viscosity ηsp / c of (co) polymer (A) As a 0.4 g / 100 ml methyl ethyl ketone solution, a sample to be measured was subjected to ηsp at 30 ° C. using a Ubbelohde viscometer. / C was measured. (4) Reduced viscosity ηsp / c of graft component (d) 200 ml of acetone was added to 1 g of the graft copolymer sample, and the mixture was refluxed in a water bath at 70 ° C. for 3 hours.
00r. p. m. After centrifugation at (10000 G) for 40 minutes, the insoluble matter is filtered. The filtrate was concentrated with a rotary evaporator, and the precipitate (acetone-soluble matter) was dried under reduced pressure at 60 ° C. for 5 hours.
As a 00 ml methyl ethyl ketone solution, ηsp / c was measured at 30 ° C. using an Ubbelohde viscometer. (5) Refractive index of (co) polymer (A) and rubbery polymer (b) A small amount of 1-bromonaphthalene was dropped on a sample to be measured, and the refractive index was measured using Abbe refractometer under the following conditions. .

Light source: sodium lamp D line Measurement temperature: 20 ° C. (6) Refractive index of graft component (d) A precipitate obtained after drying under reduced pressure obtained by the same operation as in (4) is used as a sample in the same manner as in (5). The refractive index was measured as the refractive index of the graft component (d). (7) Color tone (YI value): based on JIS K7103. (8) Transparency (Haze value) Toshiba Corporation pellets of the resin composition dried in an 80 ° C. hot air dryer for 3 hours were set at a cylinder temperature of 250 ° C.
The haze value [%] of a square plate molded product (thickness: 3 mm) which was filled into an IS50A molding machine and molded immediately was measured by the Toyo Seiki Co., Ltd.
It measured using the direct reading haze meter. (9) Izod impact strength: ASTM D256 (23
(° C, with V notch) (10) Tensile strength: according to ASTM 638.

Reference Example (B) Graft Copolymer B-1: Polybutadiene latex (rubber particle diameter 0.3
μm, gel content 85%) 50 parts (in terms of solid content), pure water 2
00 parts, sodium formaldehyde sulfoxylate 0.4 part, sodium ethylenediaminetetraacetate 0.1
, Ferrous sulfate (0.01 part) and sodium phosphate (0.1 part) were charged into a reaction vessel, and after purging with nitrogen, the temperature was adjusted to 65 ° C, and 11.5 parts of styrene and acrylonitrile were stirred under stirring.
A mixture of 0 part, 34.5 parts of methyl methacrylate, and 0.3 part of n-dodecyl mercaptan was continuously added dropwise over 4 hours. At the same time, 0.25 part of cumene hydroperoxide and 2.5% of sodium laurate as an emulsifier
And a mixture of 25 parts of pure water were continuously added dropwise over 5 hours, and after the completion of the addition, the mixture was maintained for another 1 hour to complete the polymerization.

The latex after polymerization was coagulated with 1.5% sulfuric acid, then neutralized with sodium hydroxide, washed, centrifuged and dried to prepare a powdery graft copolymer. Table 3 shows the graft characteristics and the refractive index of the graft component.
As shown in FIG. B-2, 3: The graft copolymer shown in Table 3 was produced in the same manner as in B-1, except that the vinyl monomer mixture having the composition shown in Table 3 was used.

[0047]

EXAMPLE 1 Two polymerization tanks having the specifications shown in Table 1 below, a preheater, a demonomerizer, and 1 /
Using a continuous bulk polymerization apparatus consisting of a twin-screw extruder-type feeder having a heating device connected to a three-length barrel in tandem, 23.0 parts of styrene and 8.0 of acrylonitrile were used.
, 69.0 parts of methyl methacrylate, 0.15 part of n-octylmercaptan and 0.01 part of di-t-butyl peroxide are continuously supplied to the first polymerization tank at 150 kg / hour. Then, continuous bulk polymerization was carried out. The polymerization rate of the first polymerization tank was between 48 and 51%, and the polymer from the second polymerization tank was operated while being controlled between 80 and 81%.
The polymerization reaction mixture is then fed to a single-screw extruder type demonomer, where the unreacted monomer is recovered by evaporation under reduced pressure from the vent port, and the unreacted monomer is continuously refluxed to the first polymerization tank. The styrene / acrylonitrile / methyl methacrylate copolymer whose apparent polymerization rate has risen to 99% or more at one third from the tip of the demonomerizer is a phenol-based stabilizer from a twin-screw extruder type feeder. 0.225 kg / h of t-butylhydroxytoluene and 0.225 kg of tri (nonylphenyl) phosphite as a phosphorus-based stabilizer
/ Hour and the graft copolymer (B-
1) was supplied in a semi-molten state at a rate of 75 kg / hour, and was melt-kneaded with a styrene / acrylonitrile / methyl methacrylate copolymer by a demonomerizer, and then discharged in a strand form to obtain a resin composition pellet by a cutter. . Table 5 shows the evaluation results of the resin characteristics.

[0048]

[Table 1] Examples 2 and 3 Example 1 and Example 2 were repeated except that the graft copolymer (B-2, 3) produced in Reference Example was supplied in a semi-molten state at a rate shown in Table 4 from a heated twin-screw extruder type feeder. Similarly, resin composition pellets were obtained. Table 5 shows the evaluation results of the resin characteristics. Example 4 A twin-screw extruder type having one polymerization tank having the specifications shown in Table 2 below, a preheating machine, a demonomerization machine, and a heating device connected in tandem to a barrel portion having a length of 1/3 from the tip of the demonomerization machine. Using a continuous bulk polymerization apparatus composed of a feeder, 9.0 parts of styrene, 2.0 parts of acrylonitrile, 73 parts of methyl methacrylate, 16 parts of N-phenylmaleimide, 0.18 part of n-octylmercaptan and 0.1 parts of di-t-butyl A monomer mixture consisting of 0.01 part of peroxide
The mixture was continuously supplied to the polymerization tank at a rate of kg / hour to perform continuous polymerization. The operation was performed while controlling the degree of polymerization at the polymerization tank between 74% and 76%. After the polymerization reaction mixture is preheated by a single screw extruder type preheater, unreacted monomers are recovered by evaporation under reduced pressure from a vent port by a twin screw extruder type demonomer machine, and the unreacted monomers are continuously collected. Reflux to the polymerization tank, 1/3 from the end of the demonomerizer
The styrene / acrylonitrile / methyl methacrylate / N-phenylmaleimide copolymer whose apparent polymerization rate has risen to 99% or more at
55 kg of the graft copolymer (B-3) produced in Reference Example together with 0.175 kg / hour of -butylhydroxytoluene and 0.175 kg / hour of tri (nonylphenyl) phosphite as a phosphorus-based stabilizer in a semi-molten state. / Hour, and styrene / acrylonitrile /
After melt-kneading with a methyl methacrylate / N-phenylmaleimide copolymer, the mixture was pelletized. Table 5 shows the evaluation results of the resin characteristics.

[0049]

[Table 2] Example 5 A graft copolymer (B-1) produced in Reference Example from a heated twin-screw extruder type feeder was heated in a semi-molten state at 40 kg / kg.
A resin composition pellet was obtained in the same manner as in Example 4 except that the resin composition was supplied at the time. Table 5 shows the evaluation results of the resin characteristics. Comparative Example 1 Using a continuous bulk polymerization apparatus comprising two tanks having the specifications shown in Table 1, a preheater, and a demonomerizer, styrene was used at 23.0.
Part, acrylonitrile 8.0 parts, methyl methacrylate 6
A monomer mixture consisting of 9.0 parts, 0.15 part of n-octyl mercaptan and 0.01 part of di-t-butyl peroxide is continuously supplied to the first polymerization tank at a rate of 150 kg / hour and subjected to continuous bulk polymerization. Was. The polymerization rate of the first polymerization tank is 58-6.
1%, and the polymer discharged from the second polymerization tank is 90 to 9%.
The operation was controlled between 1%. The polymerization reaction mixture is then fed to a single-screw extruder type demonomer, where the unreacted monomer is recovered by evaporation under reduced pressure from the vent port, and the unreacted monomer is continuously refluxed to the first polymerization tank. , Apparent polymerization rate of 9
At 9% or more, the mixture was discharged in a strand shape and pelletized by a cutter. The obtained styrene / acrylonitrile / methyl methacrylate copolymer pellets and the graft copolymer (B-1) produced in Reference Example were blended in the ratio shown in Table 4, and t-butyl as a phenolic stabilizer was further added. After 0.1 part of hydroxytoluene and 0.1 part of tri (nonylphenyl) phosphite as a phosphorus-based stabilizer were added and dry-blended, the mixture was melt-kneaded / extruded and pelletized to obtain resin composition pellets. Table 5 shows the evaluation results of the resin characteristics. Comparative Example 2 In a stainless steel autoclave having a capacity of 20 L and equipped with a baffle and a Fowler-type stirring blade, 0.05 part of a copolymer composed of 20% by weight of methyl methacrylate and 80% by weight of acrylamide was dissolved in 165 parts of ion-exchanged water. The solution was stirred at 400 rpm, and the system was replaced with nitrogen gas. Next, 23.0 parts of styrene and 8.0 of acrylonitrile were used.
, A mixed solution of 69.0 parts of methyl methacrylate and 0.18 part of t-dodecylmercaptan and 0.50 part of 2,2′-azobisisobutylnitrile was added while stirring the reaction system, and the temperature was raised to 58 ° C. The polymerization was started. After 15 minutes had elapsed from the start of the polymerization, 56 parts of styrene from a feed pump provided at the top of the autoclave was added over 110 minutes. During this time, the reaction temperature was raised to 65 ° C. After the addition of styrene to the reaction system was completed, the temperature was raised to 100 ° C. over 50 minutes. Thereafter, according to the usual method, cooling of the reaction system,
The polymer was separated, washed and dried to obtain a beaded copolymer. The beads and the graft copolymer (B-1) produced in Reference Example were blended in the proportions shown in Table 4, and 0.1 part of t-butylhydroxytoluene as a phenol-based stabilizer and a phosphorus-based stabilizer were further added. 0.1 part of tri (nonylphenyl) phosphite was added and dry-blended, followed by melt-kneading / extrusion pelletizing to obtain resin composition pellets. Table 5 shows the results of the resin property evaluation.

Examples 1 to 5 show that the thermoplastic resin composition having transparency within the scope of the present invention is excellent in color tone and in balance of physical properties between impact resistance and rigidity.

However, the resin compositions obtained in Comparative Examples 1 and 2 differed in the method of mixing the (co) polymer (B) and the graft copolymer (A) from the claims of the present invention, It can be seen that the balance between physical properties of impact resistance and rigidity is poor.

[0052]

[Table 3]

[0053]

[Table 4]

[0054]

[Table 5]

[0055]

According to the present invention, a resin containing no rubber component is produced by a continuous bulk polymerization method, and a graft copolymer containing a rubber component is added in the latter half of the demonomerization step when the resin is in a molten state. The mixture is characterized by that a thermoplastic resin composition having excellent transparency and excellent color tone and mechanical strength can be obtained. According to the production method of the present invention,
Wastewater treatment can be reduced, and furthermore, the number of manufacturing steps is reduced and manufacturing costs can be reduced.

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Claims (7)

[Claims] 1. A rubbery polymer is added to 10 to 95 parts by weight of a (co) polymer (A) in a molten state during a process of continuously bulk polymerizing one or more vinyl monomer mixtures (a). Graft copolymer (B) obtained by graft-polymerizing one or more kinds of vinyl monomer mixture (c) in the presence of (b)
A thermoplastic resin composition having transparency by adding and mixing 90 to 5 parts by weight. 2. A (co) polymer (A) and a rubbery polymer (b)
2. The thermoplastic resin composition having transparency according to claim 1, wherein a difference in refractive index between the thermoplastic resin and the thermoplastic resin is 0.03 or less. 3. The rubber composition according to claim 1, wherein the difference in refractive index between the graft component (d) and the rubbery polymer (b) constituting the graft copolymer (B) is within 0.03. 2
A thermoplastic resin composition having transparency. 4. A vinyl monomer mixture (a) comprising 5 to 70% by weight of an aromatic vinyl monomer (ma1), 0 to 35% by weight of a vinyl cyanide monomer (ma2), Acid alkyl ester monomer (ma3) 30 to 95% by weight
And other monomers (ma4) 0 copolymerizable therewith.
The vinyl monomer mixture (c) is 5 to 70% by weight of an aromatic vinyl monomer (mc1), 0 to 35% by weight of a vinyl cyanide monomer (mc2), and unsaturated Carboxylic acid alkyl ester monomer (mc3) 30 to 9
5% by weight and other monomers copolymerizable therewith (mc
4) The transparent thermoplastic resin composition according to any one of claims 1 to 3, comprising 0 to 50% by weight. (5) a residual monomer amount of 10% by weight or less (co)
The thermoplastic resin composition having transparency according to any one of claims 1 to 4, wherein the graft copolymer (B) is added to the polymer (A). 6. The graft copolymer (B) is added to the (co) polymer (A) during or after the demonomerization step of the continuous bulk polymerization of the (co) polymer (A).
A thermoplastic resin composition having transparency according to any one of claims 1 to 5. 7. The thermoplastic resin composition according to claim 1, wherein the graft copolymer (B) is added in a semi-molten or molten state.