JP6387720B2 - Graft copolymer-containing powder and method for producing thermoplastic resin composition - Google Patents

Description

  The present invention provides a graft copolymer-containing powder and a graft copolymer-containing coagulum that can provide a thermoplastic resin composition excellent in impact resistance and fluidity, and excellent in impact resistance and fluidity including the same. The present invention relates to a thermoplastic resin composition and a molded product formed by molding the thermoplastic resin composition.

  ABS resin (acrylonitrile, butadiene, styrene resin) has excellent processability, impact resistance, mechanical properties, and chemical resistance, so it is used in a wide range of fields such as the vehicle field, the home appliance field, and the building material field. . In recent years, in the vehicle field, attention has been paid to the excellent secondary processability of ABS resin, in particular, plating properties and paintability, and it is used for automobile exterior applications such as door mirrors and radiator grilles. In the home appliance field, it is used for home appliances such as refrigerators and washing machines.

  However, in recent years, with regard to the injection molded products of ABS resin, the melt flow during further molding processing due to the complexity of the shape, the formation of irregularities such as ribs and bosses, and the weight reduction and thinning from the viewpoint of resource saving. There is a demand for a thermoplastic resin composition that is improved in properties, that is, excellent in moldability.

In order to solve these problems, for example, Patent Document 1 proposes a thermoplastic resin composition in which an AS resin (acrylonitrile / styrene resin) is blended with an ABS resin. However, although the thermoplastic resin composition proposed in Patent Document 1 is excellent in the plating property and impact resistance of the injection molded product, the melt fluidity during the molding process is not sufficient.
That is, impact resistance and fluidity are generally in a trade-off relationship, and those having excellent impact resistance generally tend to be inferior in fluidity, and conversely, those having excellent fluidity are usually obtained molded products. The impact resistance is low, and it has been difficult to realize a thermoplastic resin composition that is excellent in both impact resistance and fluidity in terms of blending composition and the like.

JP 2007-039489 A

  An object of the present invention is to provide a thermoplastic resin composition excellent in fluidity and impact resistance.

  As a result of intensive studies, the present inventors have found that a graft copolymer (A) in a slurry or latex state and a low-viscosity hard copolymer (B) containing a vinyl cyanide monomer unit as an essential component are latex. The present inventors have found that the above object can be achieved by a graft copolymer-containing powder or a graft copolymer-containing coagulated product obtained by mixing and coagulating in a state, and the present invention has been achieved.

  That is, this invention makes the following a summary.

[1] 100 parts by mass (solid content) of a slurry or latex graft copolymer (A) and 15 to 45 parts by mass of a latex hard copolymer (B) satisfying the following (1) to (2) (Solid content conversion) is mixed, The manufacturing method of the graft copolymer containing powder (C) which collect | recovers the graft copolymer containing powder (C) from the obtained liquid mixture.
(1) The proportion of vinyl cyanide monomer units in all monomer units constituting the hard copolymer (B) is 10 to 60% by mass.
(2) The reduced viscosity measured at 25 ° C. of a solution obtained by dissolving 0.2 g of the hard copolymer (B) in 100 ml of dimethylformamide is 0.3 to 2.0 dl / g.

[2] In [1], the graft copolymer-containing coagulated product (D) is coagulated and precipitated from the mixed solution, and the precipitate is solid-liquid separated and then dried to dry the graft copolymer-containing powder (C). For producing a graft copolymer-containing powder (C).

[3] [1] or in [2], graft copolymer (A), a rubber-like polymer 10-80 weight%, monomer component containing an aromatic alkenyl compound and a vinyl cyanide compound 90-20 A method for producing a graft copolymer-containing powder (C) , which is obtained by emulsion graft polymerization of mass% (however, the total of the rubber-like polymer and the monomer component is 100 mass%).

[4] Slurry or latex state graft copolymer (A) 100 parts by weight (solid content) and latex state hard copolymer (B) 15 to 45 parts by weight satisfying the following (1) and (2) ( A method for producing a graft copolymer-containing coagulum (D) that obtains a graft copolymer-containing coagulum (D) through a step of mixing (solid content conversion).
(1) The proportion of vinyl cyanide monomer units in all monomer units constituting the hard copolymer (B) is 10 to 60% by mass.
(2) The reduced viscosity measured at 25 ° C. of a solution obtained by dissolving 0.2 g of the hard copolymer (B) in 100 ml of dimethylformamide is 0.3 to 2.0 dl / g.

[5] In [4], the step of mixing the slurry or latex state graft copolymer (A) and the latex state hard copolymer (B), and graft copolymer-containing coagulation from the resulting mixture The manufacturing method of the graft copolymer containing coagulum (D) which obtains a graft copolymer containing coagulum (D) through the process of coagulating a product (D).

[6] The graft copolymer-containing powder (C) produced by the method for producing a graft copolymer-containing powder (C) according to any one of [1] to [3] is used. A method for producing a thermoplastic resin composition.

[7] [4] or [5] The thermoplastic resin, which comprises using the graft copolymer containing coagulum produced by the production method of the graft copolymer-containing solidified product according (D) (D) is in A method for producing the composition.

[8] [6] or [7] The method for producing a molded article for molding the thermoplastic resin composition produced by the method for producing a thermoplastic resin composition according to.

According to the graft copolymer-containing powder and the graft copolymer-containing coagulated product of the present invention, a thermoplastic resin composition having excellent impact resistance and fluidity can be provided.
According to the thermoplastic resin composition of the present invention, a molded product having a complex deformed shape, a thin-walled product, or a small-sized molded product can be molded with a good yield with good moldability and excellent shape accuracy. In addition, a molded article having excellent impact resistance and mechanical durability can be obtained.

  Hereinafter, the present invention will be described in detail.

The graft copolymer-containing powder (C) and the graft copolymer-containing coagulum (D) of the present invention are essential for the graft copolymer (A) in a slurry or latex state and a vinyl cyanide monomer unit. It is obtained through a step of mixing the latex of the low-viscosity hard copolymer (B) as a component at a predetermined ratio together in a liquid state (hereinafter referred to as “latex mixing”).
In this way, the graft copolymer (A) and the hard copolymer (B) are mixed in a latex, whereby the graft copolymer (A) particles and the hard copolymer (B) particles are made into a single fine particle. As a result of being uniformly mixed at the particle level and solidifying in the subsequent solidification process in the uniform mixed state, the inherent impact resistance of the graft copolymer (A) and the inherent fluidity of the hard copolymer (B) are obtained. It becomes possible to obtain a graft copolymer-containing powder (C) or a graft copolymer-containing coagulum (D) that can be exhibited well in a good balance.
On the other hand, the graft copolymer (A) powder obtained by coagulating and recovering the graft copolymer (A) from the latex of the graft copolymer (A), and the hard copolymer (B) Even when the powder of the hard copolymer (B) recovered from the latex is mixed in the powder state (hereinafter referred to as “powder mixing”), the graft copolymer (A) and the hard copolymer are mixed. (B) is simply mixed as agglomerated particles aggregated to a certain size, and both are not mixed in a state of being uniformly dispersed at the level of fine particles, so that impact resistance and fluidity are eliminated. Cannot be obtained, and the impact resistance is particularly poor.

<Graft copolymer (A)>
The graft copolymer (A) in a slurry or latex state used in the present invention can be produced by emulsion graft polymerization of a copolymerizable monomer component in the presence of a rubbery polymer.

The rubbery polymer used for the graft copolymer (A) is not particularly limited, and examples thereof include diene rubbers such as polybutadiene, alkyl (meth) acrylate rubbers such as butyl acrylic rubber, and ethylene-propylene rubbers. Examples thereof include ethylene-propylene copolymer rubber, polyorganosiloxysan rubber, diene / alkyl (meth) acrylate composite rubber, polyorganosiloxysan / alkyl (meth) acrylate composite rubber, and the like. Preferred are diene rubbers such as polybutadiene and diene / alkyl (meth) acrylate composite rubbers.
These rubber-like polymers can be used individually by 1 type or in combination of 2 or more types.

  The gel content of the rubbery polymer is preferably 50 to 99% by mass, more preferably 60 to 95% by mass, and particularly preferably 70 to 85% by mass. When the gel content is within this range, the properties of the resulting thermoplastic resin composition, particularly the impact strength, can be improved.

  In order to measure the gel content of the rubbery polymer, specifically, the weighed rubbery polymer was dissolved in an appropriate solvent at room temperature (23 ° C.) over 20 hours, and then 100 mesh. After separating with a wire mesh, the insoluble matter remaining on the wire mesh is dried at 60 ° C. for 24 hours and then weighed. The ratio (mass%) of the insoluble matter with respect to the rubber-like polymer before fractionation is calculated | required and it is set as gel content of a rubber-like polymer. As the solvent used for dissolving the rubber-like polymer, for example, toluene is used for polybutadiene and acetone is used for polybutyl acrylate.

  The particle size of the rubbery polymer is not particularly limited, but is preferably an average particle size of 0.1 to 1 μm, and more preferably 0.2 to 0.5 μm. The average particle diameter of the rubber-like polymer can be measured by an optical method before graft polymerization. Further, after graft polymerization, the average particle diameter can be calculated using a transmission electron microscope (TEM) after dyeing the rubbery polymer with a dyeing agent.

  Examples of the monomer component to be graft-polymerized on the rubber-like polymer described above include aromatic alkenyl compounds, methacrylic acid esters, and acrylic acid esters (hereinafter, these may be collectively referred to as “(meth) acrylic acid esters”). And vinyl cyanide compounds. Among these monomer components, examples of the aromatic alkenyl compound include styrene, α-methylstyrene, vinyltoluene, and the like. Examples of the methacrylic acid ester include methyl methacrylate, ethyl methacrylate, 2-ethylhexyl methacrylate and the like. Examples of acrylic acid esters include methyl acrylate, ethyl acrylate, butyl acrylate, and the like. Examples of the vinyl cyanide compound include acrylonitrile and methacrylonitrile. These can be used alone or in combination of two or more.

  Among these, when a mixture of an aromatic alkenyl compound, preferably styrene, and a vinyl cyanide compound, preferably acrylonitrile, is used as the monomer component of the graft portion, the thermal stability of the graft copolymer (A) is excellent. Therefore, it is preferable. In this case, the ratio of the aromatic alkenyl compound such as styrene and the vinyl cyanide compound such as acrylonitrile is preferably 10 to 50% by mass of the vinyl cyanide compound with respect to 50 to 90% by mass of the aromatic alkenyl compound ( However, the total of the aromatic alkenyl compound and the vinyl cyanide compound is 100% by mass.)

  The graft copolymer (A) is obtained by emulsion graft polymerization of 90 to 20% by mass of the graft part monomer component with respect to 10 to 80% by mass of the rubbery polymer (however, the rubbery polymer and 100% by mass in total with the monomer components) is preferable because the resulting molded article has an excellent appearance. More preferably, in the graft copolymer (A), the rubber-like polymer is 30 to 70% by mass, and the graft part monomer component is 70 to 30% by mass.

  The emulsion graft polymerization for producing the graft copolymer (A) is performed by a radical polymerization technique using an emulsifier. Various chain transfer agents for controlling the graft ratio and the molecular weight of the graft component can be added to the graft portion monomer component.

  The radical polymerization initiator used in the polymerization is not particularly limited, but a peroxide, an azo initiator, or a redox initiator combined with an oxidizing agent / reducing agent is used. Of these, redox initiators are preferred, especially redox initiators that combine ferrous sulfate, sodium pyrophosphate, glucose, hydroperoxide, ferrous sulfate, ethylenediaminetetraacetic acid disodium salt, longalite, hydroperoxide. Agents are preferred.

  There are no particular restrictions on the emulsifier, but since it has excellent latex stability during emulsion polymerization and can increase the polymerization rate, various kinds of sodium sarcosinate, potassium fatty acid, sodium fatty acid, dipotassium alkenyl succinate, rosin acid soap, etc. An anionic emulsifier selected from carboxylates, alkyl sulfates, sodium alkylbenzene sulfonate, sodium polyoxyethylene nonylphenyl ether sulfate and the like is preferably used. These are properly used according to the purpose. The emulsifier used for the preparation of the rubbery polymer can be used as it is, and no additional emulsifier can be added during the emulsion graft polymerization.

  In the production of a general graft copolymer, a latex of a graft copolymer is obtained by graft polymerization of a monomer component to a rubber-like polymer by emulsion polymerization, and the resulting latex of the graft copolymer is obtained. The graft copolymer powder is obtained by coagulation, washing, dehydration, and drying steps. In the present invention, the latex of the graft copolymer (A) is used as it is or coagulated as a slurry, Subject to the next mixing step.

  When the graft copolymer (A) is coagulated from the latex of the graft copolymer (A) to form a slurry, for example, the graft copolymer (A) latex is put into hot water in which a coagulant is dissolved. Thus, a wet method for coagulating into a slurry can be employed. Here, examples of the coagulant used include inorganic acids such as sulfuric acid, hydrochloric acid, phosphoric acid, and nitric acid, and metal salts such as calcium chloride, calcium acetate, and aluminum sulfate, and are selected according to the emulsifier used in the polymerization. The That is, when only a carboxylic acid soap such as fatty acid soap or rosin acid soap is used as an emulsifier, the graft copolymer (A) can be coagulated and precipitated using any coagulant, From the viewpoint of stability, it is preferable to solidify and precipitate the graft copolymer (A) using an inorganic acid. When an emulsifier exhibiting stable emulsifying power is contained even in an acidic region such as sodium alkylbenzene sulfonate, the recovered solution becomes turbid with the above-mentioned inorganic acid, and the precipitation of the graft copolymer (A) is difficult. It is necessary to use a metal salt as an agent.

Graft ratio of the graft copolymer (A) thus obtained (determined from the amount of acetone-soluble and insoluble components in the graft copolymer (A) and the weight of the rubbery polymer in the graft copolymer (A)). ), And the reduced viscosity (measured as a N, N-dimethylformamide solution at 25 ° C. at 0.2 g / dL, acetone) is not particularly limited, and those having an arbitrary structure may be used depending on the required performance. However, from the viewpoint of balance of physical properties, the graft ratio is preferably 5 to 150%, and the reduced viscosity is preferably 0.2 to 2.0 g / dL.
In addition, the graft ratio of the graft copolymer (A) and the reduced viscosity of the acetone-soluble component are specifically determined by the method described in the section of Examples described later.

  Moreover, it is preferable that the solid content density | concentration of graft copolymer (A) latex or slurry is about 10-50 mass% from the surface of workability | operativity and productivity in the following mixing process.

<Hard copolymer (B)>
The hard copolymer (B) used in the present invention is an essential component in a proportion of 10 to 60% by mass of vinyl cyanide monomer units in all monomer units constituting the hard copolymer (B). As other components, it contains 40 to 90% by mass of at least one selected from the group consisting of aromatic alkenyl monomer units, (meth) acrylic acid ester monomer units, etc. 100% by mass in total of vinyl monomer units and other monomer units). The content of the vinyl cyanide monomer unit in the hard copolymer (B) is preferably 15 to 55% by mass, more preferably 20 to 50% by mass. When this proportion is less than 10% by mass, the resulting thermoplastic resin composition has poor impact resistance, and when it exceeds 60% by mass, there is a problem of thermal coloring of the thermoplastic resin composition. Become prominent.

  Vinyl cyanide compound constituting vinyl cyanide monomer that can be used for production of hard copolymer (B), aromatic alkenyl compound constituting aromatic alkenyl monomer unit, and (meth) acrylic acid As an example of the (meth) acrylic acid ester which comprises an ester monomer unit, what was illustrated as a monomer component used for manufacture of the said graft copolymer (A) can be used.

  By producing the hard heavy copolymer (B) by an emulsion polymerization method, it is possible to obtain a hard copolymer (B) in a latex state, which can be used for the next mixing step as it is, which is preferable. About the emulsifier and initiator used in that case, the thing similar to what was illustrated as what is used for manufacture of a graft copolymer (A) can be used.

  The hard copolymer (B) has a reduced viscosity (hereinafter simply referred to as “reduced viscosity”) of 0.3 to 2.0 dl measured at 25 ° C. with respect to a solution obtained by dissolving 0.2 g of the hard copolymer (B) in 100 ml of dimethylformamide. / G. This reduced viscosity is preferably 0.35 to 1.0 dl / g, more preferably 0.4 to 0.6 dl / g. When the reduced viscosity of the hard copolymer (B) is less than 0.3 dl / g, the impact resistance of the resulting thermoplastic resin composition is inferior, whereas it exceeds 2.0 dl / g. In this case, the fluidity of the thermoplastic resin composition is significantly reduced.

  Any method may be used to adjust the reduced viscosity of the hard copolymer (B). However, a method of changing or using the chain transfer agent, a method of changing the amount of initiator used, a polymerization temperature, And a method of changing a method for supplying a monomer as a raw material.

  The solid content concentration of the hard copolymer (B) latex used in the present invention is preferably about 20 to 50% by mass from the viewpoint of workability and productivity in the next mixing step.

<Mixing process>
There is no particular limitation on the method of mixing the graft copolymer (A) in the slurry or latex state and the hard copolymer (B) in the latex state, and the graft copolymer (A) in the slurry or latex state is in the latex state. The hard copolymer (B) may be added and mixed, or the slurry or latex hard copolymer (B) may be added to and mixed with the latex hard copolymer (B). . Although mixing time is not specifically limited, 3 minutes or more are preferable, and it is preferable to make mixing time into the range for 5 to 30 minutes from the surface of uniform mixing property and productivity.

  The rigid copolymer (B) is 15 to 45 parts by mass (as solid content), preferably 20 to 40 parts by mass, more preferably 100 parts by mass (as solid content) of the graft copolymer (A). It mixes so that it may become 25-35 mass parts. When the mixing ratio of the hard copolymer (B) is less than 15 parts by mass, the effect of improving the fluidity is small, and when it exceeds 45 parts by mass, the impact property of the obtained thermoplastic resin composition is lowered.

<Coagulation process>
As a method for precipitating the graft copolymer-containing coagulum (D) from the mixed solution of the graft copolymer (A) and the hard copolymer (B) obtained in the above mixing step, a coagulant was dissolved. There is a wet method in which the latex of the mixed liquid is coagulated in a slurry state in hot water.

  Examples of the coagulant used in the wet coagulation method include inorganic acids such as sulfuric acid, hydrochloric acid, phosphoric acid and nitric acid, and metal salts such as calcium chloride, calcium acetate and aluminum sulfate, and the graft copolymer (A) and hard The emulsifier used in the polymerization of the copolymer (B) (in the case of mixing the graft copolymer (A) in the slurry state and the hard copolymer (B) in the latex state, the polymerization of the hard copolymer (B) It is selected according to the emulsifier used). That is, when only a carboxylic acid soap such as a fatty acid soap or a rosin acid soap is used as an emulsifier, the graft copolymer-containing coagulum (D) can be precipitated using any coagulant. In the case where an emulsifier exhibiting stable emulsifying power is contained even in an acidic region such as sodium sulfonate, the above inorganic acid is insufficient, and a metal salt needs to be used as a coagulant.

  When wet coagulation is performed using a coagulant such as sulfuric acid, the concentration of the coagulant in hot water is preferably 1 to 10% by mass, and the temperature of the hot water is preferably about 50 to 100 ° C. When the graft copolymer (A) and the hard copolymer (B) are mixed at about 10 to 150 parts by mass with respect to 100 parts by mass of the mixed latex, efficient coagulation and recovery can be performed.

  The graft copolymer-containing coagulated product (D) obtained by the wet coagulation method is recovered by solid-liquid separation from the slurry, and washed to elute and remove the remaining emulsifier residue in water.

  Although it does not restrict | limit especially as this washing | cleaning conditions, It wash | cleans on the conditions from which the amount of emulsifier residues contained in the graft copolymer containing powder (C) after the below-mentioned drying (C) in the range of 0.5 to 2% by mass is contained. It is preferable to do. If the amount of the emulsifier residue in the graft copolymer-containing powder (C) is 0.5% by mass or more, the fluidity of the obtained graft copolymer-containing powder (C) and the resin composition containing the same is further improved. Tend to. On the other hand, if the emulsifier residue in the graft copolymer-containing powder (C) is 2% by mass or less, gas generation can be suppressed when the resin composition is molded at a high temperature. Hereinafter, the content of the emulsifier residue in the graft copolymer-containing powder (C) after drying is simply referred to as “emulsifier residue content”.

<Drying process>
As a method of obtaining the graft copolymer-containing powder (C) in a dry state after solid-liquid separation and washing of the graft copolymer-containing coagulated product (D) as described above, the graft copolymer after washing is used. Examples thereof include a method in which the slurry of the contained coagulum (D) is dehydrated by centrifugation or a press dehydrator and then dried by an air dryer, a method in which dehydration and drying are simultaneously performed by a press dehydrator or an extruder. By such a method, a powder or particulate dry graft copolymer-containing powder (C) is obtained.

  In addition, the graft copolymer-containing powder (C) discharged from the press dehydrator or extruder can be directly sent to the extruder or molding machine for producing the resin composition to obtain a molded product. It is.

<Thermoplastic resin composition>
The thermoplastic resin composition of the present invention contains the above-mentioned graft copolymer-containing powder (C) and / or graft copolymer-containing coagulum (D) of the present invention, and contains a graft copolymer as necessary. It contains a thermoplastic resin component other than the powder (C) and / or the graft copolymer-containing coagulum (D). Examples of other thermoplastic resins that can be contained in the thermoplastic resin composition of the present invention include diene rubber, alkyl (meth) acrylate rubber, ethylene-propylene copolymer rubber, polyorganosiloxane rubber, diene / Alkyl (meth) acrylate composite rubber, polyorganosiloxane / alkyl (meth) acrylate composite rubber, acrylonitrile-styrene copolymer, acrylonitrile-styrene-methyl methacrylate terpolymer, styrene-methyl methacrylate copolymer , Polycarbonate, polyester, polyamide, polyphenylene ether and the like.
Only 1 type of these resin components may be contained in the thermoplastic resin composition of this invention, and 2 or more types may be contained.

  When the thermoplastic resin composition of the present invention contains other resin components other than the graft copolymer-containing powder (C) and / or the graft copolymer-containing coagulum (D) of the present invention, the graft of the present invention In order to effectively obtain excellent fluidity and impact resistance by the copolymer-containing powder (C) and / or the graft copolymer-containing coagulum (D), all of the components contained in the thermoplastic resin composition of the present invention. It is preferable that the ratio of the other resin component in 100 mass parts of resin components is 80 mass parts or less.

  The thermoplastic resin composition of the present invention may also contain additives such as dyes, pigments, stabilizers, reinforcing agents, fillers, flame retardants, foaming agents, lubricants, and plasticizers as necessary.

<Molded product>
The thermoplastic resin composition of the present invention is made a desired molded article by various molding methods such as injection molding, extrusion molding, blow molding, compression molding, calendar molding, inflation molding and the like.

  Industrial examples of the molded product of the present invention formed by molding the thermoplastic resin composition of the present invention include vehicle parts, especially various exterior / interior parts used without painting, building materials such as wall materials and window frames. Examples include home appliance parts such as parts, tableware, toys, vacuum cleaner housings, television housings, and air conditioner housings, interior members, ship members, and communication equipment housings.

  EXAMPLES Hereinafter, the present invention will be described more specifically with reference to synthesis examples, examples, and comparative examples. However, the present invention is not limited to the following examples unless it exceeds the gist.

  In the following, “part” means “part by mass” and “%” means “mass%”.

[Production of graft copolymer]
The graft ratio and the reduced viscosity of the acetone-soluble component of the graft copolymers produced in Synthesis Examples 1 and 2 below were measured by the following method.

<Graft ratio of graft copolymer>
80 mL of acetone was added to 2.5 g of the graft copolymer, and the mixture was refluxed in a 65 ° C. water bath for 3 hours to extract acetone-soluble components. The remaining acetone insolubles were separated by centrifugation, the weight after drying was measured, and the weight ratio of acetone insolubles in the graft copolymer was calculated. The graft ratio was calculated from the weight ratio of acetone insolubles in the obtained graft copolymer using the following formula.

<Reduced viscosity of acetone-soluble matter of graft copolymer>
About the N, N-dimethylformamide solution prepared so that the concentration of the acetone soluble part of the graft copolymer is 0.2 dL / g, the reduced viscosity at 25 ° C. using an Ubbelohde viscometer: η _sp / C ( Unit: dL / g) was measured.

<Synthesis Example 1: Production of Graft Copolymer (A-1)>
A graft copolymer (A-1) was produced with the following composition.
[Combination]
62.5 parts polybutadiene latex (as solids)
Styrene (ST) 28.1 parts Acrylonitrile (AN) 9.4 parts Disproportionated potassium rosin acid 1 part Potassium hydroxide 0.03 parts Tertiary decyl mercaptan (t-DM) 0.22 parts Cumene hydroperoxide 0. 30 parts Ferrous sulfate 0.007 parts Sodium pyrophosphate 0.12 parts Crystalline glucose 0.30 parts Distilled water 190 parts

  An autoclave is charged with distilled water, disproportionated potassium rosinate, potassium hydroxide and polybutadiene latex (gel content 85%, average particle size 0.29 μm, solid content 34.0%), heated to 60 ° C. Add ferrous iron, sodium pyrophosphate and crystalline glucose, and continuously add ST, AN, t-DM and cumene hydroperoxide over 2 hours while maintaining the temperature at 60 ° C, and then raise the temperature to 70 ° C for 1 hour. To complete the reaction. An antioxidant was added to the graft copolymer latex obtained by this reaction to obtain a graft copolymer (A-1). The solid content of the graft copolymer (A-1) in the obtained latex was 35.9%, the graft ratio was 61.4%, and the reduced viscosity of the acetone-soluble component was 0.49 g / dL.

<Synthesis Example 2: Production of Graft Copolymer (A-2)>
62.5 parts (solid content) latex of 20 parts of polybutadiene latex and 80 parts of n-butyl acrylate (gel content 70%, average particle size 0.34 μm) is used instead of the polybutadiene latex of Synthesis Example 1. A graft copolymer (A-2) was obtained in the same manner as in Synthesis Example 1 except that. The solid content of the graft copolymer (A-2) in the obtained latex was 35.8%, the graft ratio was 59.6%, and the reduced viscosity of the acetone-soluble component was 0.51 g / dL.

[Manufacture of hard copolymer]
The reduced viscosity of the hard copolymer produced in the following synthesis example was measured at 25 ° C. using an Ubbelohde viscometer after dissolving 0.2 g of the powdery copolymer recovered from the latex in 100 ml of dimethylformamide. .

<Synthesis Example 3: Production of Rigid Copolymer (B-1)>
A 5 L glass reactor equipped with a stirrer, a thermometer and a jacket-type temperature controller was charged with 335.7 parts of water, dipotassium alkenyl succinate (DR-25K manufactured by Arakawa Chemical Industries, Ltd., as an actual amount) 2.0. Part, 25 parts of acrylonitrile (AN), 75 parts of styrene (ST), and 0.4 part of tertiary lead decyl mercaptan (t-DM) were added, and the internal temperature was raised to 70 ° C. with stirring. To this was added an aqueous solution consisting of 0.25 parts sodium persulfate and 15.3 parts water. When the jacket temperature was maintained at that temperature, heat was rapidly generated from about 30 minutes later, and the internal temperature rose to 85 ° C. After the heat generation had stopped, the internal temperature was maintained at 70 ° C. for 1 hour and then cooled to obtain a latex of hard copolymer (B-1) having a solid content of 21.9% and a reduced viscosity of 0.59 dl / g.

<Synthesis Example 4: Production of Rigid Copolymer (B-2)>
Polymerization was conducted in the same manner as in Synthesis Example 3 except that the amount of tertiary lead decyl mercaptan (t-DM) was changed to 0.8 part, and a hard component having a solid content of 22.0% and a reduced viscosity of 0.41 dl / g. A latex of copolymer (B-2) was obtained.

<Synthesis Example 5: Production of hard copolymer (B-3)>
Polymerization was conducted in the same manner as in Synthesis Example 3 except that the amount of tertiary lead decyl mercaptan (t-DM) was changed to 1.2 parts, and a hard component having a solid content of 21.5% and a reduced viscosity of 0.32 dl / g. A latex of copolymer (B-3) was obtained.

<Synthesis Example 6: Production of hard copolymer (b-1)>
Polymerization was carried out in the same manner as in Synthesis Example 3 except that tertiary lead decyl mercaptan (t-DM) was not used, and a hard copolymer having a solid content of 21.7% and a reduced viscosity of 4.31 dl / g ( The latex of b-1) was obtained.

<Synthesis Example 7: Production of hard copolymer (b-2)>
Polymerization was conducted in the same manner as in Synthesis Example 3 except that the amount of tertiary lead decyl mercaptan (t-DM) was changed to 1.6 parts, and a hard component having a solid content of 21.6% and a reduced viscosity of 0.26 dl / g. A latex of copolymer (b-2) was obtained.

<Synthesis Example 8: Production of hard copolymer (b-3)>
Polymerization was conducted in the same manner as in Synthesis Example 3 except that 9 parts of acrylonitrile and 91 parts of styrene were changed to a hard copolymer (b-3 having a solid content of 21.6% and a reduced viscosity of 0.27 dl / g). ) Latex was obtained.

[Production and Evaluation of Graft Copolymer-Containing Powder]
[Example 1]
<Production of Graft Copolymer-Containing Powder (C-1)>
In a coagulator having a thermometer, a stirrer, and a steam blowing type temperature controller, 80 parts of an aqueous solution in which sulfuric acid was dissolved at a ratio of 5% was heated to 75 ° C. and stirred.
100 parts of the latex of the graft copolymer (A-1) of Synthesis Example 1 and 25 parts of the latex of the hard copolymer (B-1) of Synthesis Example 3 were mixed for 5 minutes, and this mixture was heated to the above-described heated sulfuric acid. The solution was gradually dropped into an aqueous solution to solidify. Next, the precipitate was separated, washed so that the content of the emulsifier residue was 1% or less, and then dried to obtain a graft copolymer-containing powder (C-1).

<Manufacture and evaluation of thermoplastic resin composition>
70 parts of graft copolymer-containing powder (C-1) and 30 parts of acrylonitrile-styrene copolymer produced by suspension polymerization (“UMG AXS Resin S102N” manufactured by UMG ABS Co., Ltd.) -Was mixed, and this mixture was supplied to an extruder heated to 260 ° C and kneaded to obtain pellets. Test pieces were molded from the obtained pellets by an injection molding machine set at a cylinder temperature of 260 ° C and a mold temperature of 60 ° C.
With this test piece, Charpy impact strength was measured by the following method. Moreover, the melt volume rate (MVR) was measured with the following method with the obtained pellet. The measurement results are shown in Table 1-A.

<Measurement of Charpy impact strength>
In accordance with ISO 179, measurement was performed in a 23 ° C. atmosphere.

<Measurement of melt volume rate (MVR)>
According to the ISO 1133 standard, MVR was measured under the condition of 220 ° C.-98N. In addition, MVR becomes a standard of the fluidity | liquidity of a thermoplastic resin composition.

[Examples 2-3, 5-7, Comparative Examples 1-5, 7-11]
As graft copolymers and hard copolymers, those shown in Table 1-A and Table 1-B were used in the proportions shown in Table 1-A and Table 1-B, and mixed and coagulated in the same manner as in Example 1. , Dried, and graft copolymer-containing powders (C-2) to (C-3), (C-5) to (C-7), (c-1) to (c-5), (C-7) to (c-11) were obtained, and in the same manner as in Example 1, the obtained graft copolymer-containing powder and acrylonitrile-styrene copolymer were mixed to produce a thermoplastic resin composition. Similarly, Charpy impact strength and melt volume rate (MVR) were measured. The results are shown in Table 1-A and Table 1-B.

[Example 4]
<Production of Graft Copolymer-Containing Powder (C-4)>
80 parts of an aqueous solution in which sulfuric acid was dissolved at a ratio of 5% was heated to 75 ° C. and stirred. Into this, 100 parts of latex of the graft copolymer (A-1) of Synthesis Example 1 was dropped and coagulated. The obtained slurry and 25 parts of latex of the hard copolymer (B-2) obtained in Synthesis Example 4 were mixed for 5 minutes, and this mixed solution was gradually added to 80 parts of 5% aqueous sulfuric acid solution heated to 75 ° C. It was dripped and solidified. Next, the precipitate was separated, washed so that the emulsifier residue content was 1% or less, and then dried to obtain a graft copolymer-containing powder (C-4).

<Manufacture and evaluation of thermoplastic resin composition>
In the same manner as in Example 1, the obtained graft copolymer-containing powder (C-4) and acrylonitrile-styrene copolymer were mixed to produce a thermoplastic resin composition. Similarly, Charpy impact strength and melt The volume rate (MVR) was measured and the results are shown in Table 1-A.

[Example 8]
Graft copolymer-containing powder (C) as in Example 4 except that the graft copolymer (A-2) obtained in Synthesis Example 2 was used instead of the graft copolymer (A-1). -8) and using the graft copolymer-containing powder (C-8) obtained in the same manner as in Example 1, a thermoplastic resin composition with an acrylonitrile-styrene copolymer was produced, and Charpy was similarly produced. Impact strength and melt volume rate (MVR) were measured. The results are shown in Table 1-B.

[Comparative Example 6]
<Production of Graft Copolymer-Containing Powder (c-6)>
80 parts of an aqueous solution in which sulfuric acid was dissolved at a ratio of 5% was heated to 75 ° C. and stirred. Into this, 100 parts of latex of the graft copolymer (A-1) of Synthesis Example 1 was dropped and coagulated.
Similarly, 25 parts of the hard copolymer (B-2) of Synthesis Example 4 was dropped into 20 parts of 5% sulfuric acid aqueous solution heated to 75 ° C. and solidified. These precipitates were separated, washed, dried and then mixed to obtain a graft copolymer-containing powder (c-6).

<Manufacture and evaluation of thermoplastic resin composition>
In the same manner as in Example 1, the obtained graft copolymer-containing powder (c-6) and acrylonitrile-styrene copolymer were mixed to produce a thermoplastic resin composition. Similarly, Charpy impact strength and melt The volume rate (MVR) was measured and the results are shown in Table 1-A.

[Comparative Example 12]
Graft copolymer-containing powder (c) in the same manner as in Comparative Example 6 except that the graft copolymer (A-2) obtained in Synthesis Example 2 was used instead of the graft copolymer (A-1). -12), a thermoplastic resin composition with an acrylonitrile-styrene copolymer is produced using the graft copolymer-containing powder (c-12) obtained in the same manner. Similarly, Charpy impact strength and melt Volume rate (MVR) was measured. The results are shown in Table 1-B.

From the results of the above examples and comparative examples, the following has become clear.
The thermoplastic resin compositions of Examples 1 to 8 were excellent in both Charpy impact strength and melt fluidity.
On the other hand, the thermoplastic resin compositions of Comparative Examples 1 to 12 were inferior in any of the items of Charpy impact strength and melt fluidity. Specifically, in the thermoplastic resin compositions of Comparative Examples 1 and 7, the flowability decreased because the reduced viscosity of the hard copolymer was too high. The thermoplastic resin compositions of Comparative Examples 2 and 8 had a reduced Charpy impact strength because the reduced viscosity of the hard copolymer was too low. The thermoplastic resin compositions of Comparative Examples 3 and 9 are inferior in melt fluidity because the amount of the hard copolymer added is small. In the thermoplastic resin compositions of Comparative Examples 4 and 10, the Charpy impact strength decreased because the amount of the hard copolymer added was too large. In the thermoplastic resin compositions of Comparative Examples 5 and 11, the Charpy impact strength decreased because the content of acrylonitrile units in the hard copolymer was small. In the thermoplastic resin compositions of Comparative Examples 6 and 12, the Charpy impact strength decreased because the graft copolymer and the hard copolymer were mixed with powder instead of latex.

  The thermoplastic resin composition of the present invention using the graft copolymer-containing powder (C) and / or the graft copolymer-containing coagulated product (D) of the present invention has high fluidity while maintaining impact resistance. Is expressed. Since the balance between the impact resistance and the fluidity is very excellent as compared with the conventional thermoplastic resin composition, the utility value as various industrial materials is extremely high.

Claims (8)

Slurry or latex graft copolymer (A) 100 parts by mass (solid content) and latex hard copolymer (B) 15 to 45 parts by mass (solid content) satisfying the following (1) to (2) equivalent) were mixed and the resulting production method of a graft copolymer containing powder from a mixture for recovering the graft copolymer-containing powder (C) (C).
(1) The proportion of vinyl cyanide monomer units in all monomer units constituting the hard copolymer (B) is 10 to 60% by mass.
(2) The reduced viscosity measured at 25 ° C. of a solution obtained by dissolving 0.2 g of the hard copolymer (B) in 100 ml of dimethylformamide is 0.3 to 2.0 dl / g. 2. The graft copolymer-containing powder (C) is recovered by solidifying the precipitate (D) containing the graft copolymer from the mixed solution and separating the precipitate, followed by drying. A method for producing a graft copolymer-containing powder (C). According to claim 1 or 2, graft copolymer (A), rubber-like polymer 10-80 wt% and an aromatic alkenyl compound and 90-20% by weight monomer component containing a vinyl cyanide compound (provided that A method for producing a graft copolymer-containing powder (C) , which is obtained by emulsion graft polymerization of a rubber-like polymer and a monomer component in total of 100% by mass). 100 parts by weight (solid content) of the graft copolymer (A) in a slurry or latex state, and 15 to 45 parts by weight (in terms of solid content) of the latex state hard copolymer (B) that satisfies the following (1) and (2) ) To obtain a graft copolymer-containing coagulum (D). A method for producing a graft copolymer-containing coagulum (D).
(1) The proportion of vinyl cyanide monomer units in all monomer units constituting the hard copolymer (B) is 10 to 60% by mass.
(2) The reduced viscosity measured at 25 ° C. of a solution obtained by dissolving 0.2 g of the hard copolymer (B) in 100 ml of dimethylformamide is 0.3 to 2.0 dl / g. In Claim 4, the process of mixing the graft copolymer (A) of a slurry or a latex state, and the hard copolymer (B) of a latex state, and the graft copolymer containing coagulum (D ) the method of producing a graft copolymer containing coagulum through a step of coagulating the (graft copolymer containing coagulum obtain D) (D). Claims 1 to thermoplastic resin characterized by using a graft copolymer containing powder (C) graft copolymer containing powder produced by the production method of (C) according to any one of the 3 A method for producing the composition. The process according to claim 4 or graft copolymer containing solidified product according to 5 (D) of manufacturing the graft copolymer-containing solidified product produced by the process thermoplastic resin composition which comprises using the (D) . Method for producing a molded article for molding the thermoplastic resin composition produced by the method for producing a thermoplastic resin composition according to claim 6 or 7.