JP2011132426A - Method for producing rubber-reinforced thermoplastic resin composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rubber-reinforced thermoplastic resin composition, which is obtained by suppressing a product polymerized in the gas phase in a polymerization step, and melt-blending a rubbery matter-containing graft copolymer with a high-viscosity thermoplastic resin and has impact resistance; and an efficient and energy-saving method for producing the rubber-reinforced thermoplastic resin composition. <P>SOLUTION: The method for producing the rubber-reinforced thermoplastic resin composition comprises processes of polymerizing a copolymer (A) by continuously supplying a monomer mixture (a) containing an aromatic vinyl monomer (a1) and a vinyl cyanide monomer (a2) to a loop type reactor; continuously subjecting the copolymer (A) to devolatilization at a temperature of 100°C or higher and lower than 300°C at normal pressure (760 Torr) or lower for separating unreacted raw material mixture and the copolymer from each other to produce a copolymer (C); and continuously adding a graft-polymerized graft copolymer (D), which is prepared by graft polymerizing a monomer mixture (d) consisting of an aromatic vinyl monomer (d1) and a vinyl cyanide monomer (d2) in the presence of the rubbery polymer, to the copolymer (C) and mixing the copolymer (C) and the graft copolymer (D) together in a melt condition. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a method for producing a rubber-reinforced thermoplastic resin composition. More specifically, the present invention relates to a method for producing a rubber-reinforced thermoplastic resin composition that is excellent in color tone, physical property balance between impact resistance and rigidity, and excellent in molding processability and productivity.

  Rubber reinforced thermoplastic resin composition such as ABS resin has excellent mechanical properties, molding processability and appearance characteristics, so it is used in a wide range of fields including household electrical appliances, OA equipment and general miscellaneous goods. Has been.

  As a method for producing ABS resin, there is a method of melt blending a rubber-containing graft copolymer obtained by emulsion graft polymerization and an AS resin obtained by suspension polymerization or continuous bulk polymerization, but this method has many steps, There is a problem of high costs. On the other hand, Patent Document 1 discloses a method for producing an ABS resin in which a rubber-containing graft copolymer is directly melt-blended with a molten AS resin obtained by continuous bulk polymerization, thereby reducing process and cost. However, in this method, the polymerization is carried out in a stirred reactor, and there is a problem that a gas phase polymer is generated in the gas phase portion of the reactor, and further, a high viscosity and a high polymerization rate are heavy. There are problems such that the treatment of coalescence becomes impossible and the heat of reaction cannot be removed. In addition, because it has a process of devolatilizing the polymerization solution in the reactor using agitation and an extruder, it consumes a large amount of power and increases the energy given to the resin, resulting in significant deterioration of the resin, resulting in a final product. It was also a factor that deteriorated the physical properties of

  On the other hand, in Patent Document 2, the polymerization stability in a high-viscosity polymerization solution, which has been a problem of AS solution polymerization, is improved by continuously polymerizing AS resin using an apparatus using a static mixer and a tubular reactor. Although a method for producing an AS resin having excellent moldability is disclosed, a molten rubber-containing graft copolymer is added to a matrix resin of AS polymerized using a continuous reactor. There is no report about the technique which adds and manufactures ABS resin.

JP 7-292205 A JP-A-9-31108

  The present invention has been achieved as a result of studying the solution of the problems in the prior art described above as an issue. That is, an object of the present invention is to provide a rubber-reinforced thermoplastic resin composition having impact resistance by suppressing gas phase polymerization in the polymerization stage and melt blending a rubber-containing graft copolymer with a high-viscosity thermoplastic resin. An object is to provide an efficient and energy-saving manufacturing method of goods.

  In the present invention, a monomer mixture (a) containing an aromatic vinyl monomer (a1) and a vinyl cyanide monomer (a2) is continuously fed to a loop reactor to produce a copolymer (A ), The copolymer (A) is continuously devolatilized at a temperature of 100 ° C. or more and less than 300 ° C. and a pressure of normal pressure (760 Torr) or less, and the unreacted raw material mixture and the copolymer are separated. A step of producing a copolymer (C), and the copolymer (C) comprises an aromatic vinyl monomer (d1) and a vinyl cyanide monomer (d2) in the presence of a rubber-like polymer; The present invention relates to a method for producing a rubber-reinforced thermoplastic resin composition, wherein a graft copolymer (D) obtained by graft polymerization of a monomer mixture (d) is continuously added and mixed in a molten state.

  By this invention, the subject of the polymerization surface at the time of continuously producing a thermoplastic resin can be improved. First, it becomes possible to suppress the gas phase polymer generated in the conventional stirred reactor, and it is possible to improve problems in operation and quality. In addition, when a thermoplastic resin is continuously polymerized in a high cyanide monomer region or a high molecular weight region, there is often a problem that a polymer having a high viscosity or a polymer having a large reaction heat cannot be stably produced. The production method of the present invention enables continuous polymerization even in a polymer solution having a high viscosity copolymer, and has a reactor with excellent heat conduction efficiency, so that reaction heat can be efficiently removed. This makes it possible to produce a stable and economical thermoplastic resin.

  In addition, because it possesses a process to continuously devolatilize the polymerization solution containing the monomer, it consumes less power and reduces the energy given to the resin compared to the devolatilization process using a conventional extruder. It is possible to suppress deterioration of the resin and physical properties of the final product.

  Further, by melt blending the thermoplastic resin produced in a continuous reactor and the rubber-containing graft copolymer, production efficiency can be improved and the environmental load can be reduced by reducing the number of processes. Moreover, since the amount of heat given to the resin can be reduced, a rubber-reinforced thermoplastic resin composition excellent in color tone and physical properties can be obtained.

It is an apparatus longitudinal cross-sectional schematic diagram which shows one embodiment of the apparatus for implementing this invention method.

  Hereinafter, the details of the method for producing the rubber-reinforced thermoplastic resin composition of the present invention will be described in the order of steps.

  There are two ideal models for continuous reactors for the continuous production of thermoplastics: fully mixed flow and extruded flow. The fully mixed flow is a model in which the components in the reactor are completely uniform, and the supplied raw materials are mixed to this uniform state without any instantaneous time. The extrusion flow is a reactor in which the supplied raw material does not intersect with the raw material supplied before or after that, so that the reaction fluid is pushed out of the tube.

  In the present invention, first, (a) a monomer mixture (a) containing an aromatic vinyl monomer (a1) and a vinyl cyanide monomer (a2) is a loop-shaped reactor which is a continuous reactor having a completely mixed flow. The copolymer (A) is polymerized by continuously supplying to the reactor.

  The loop reactor in the step (a) of the present invention is a reactor in which a polymerization solution circulates, preferably a circulating reactor composed of one or more tubular reactors, more preferably It is a circulation type reactor composed of two or more tubular reactors. In addition, the loop reactor is composed of one or more tubular reactors having a structure for static mixing, so that the copolymer content is high and stable even under polymer solution conditions with increased viscosity. This is preferable because it enables economically advantageous continuous polymerization.

The tubular reactor having a structure for static mixing preferably used in the present invention is a tubular reactor in which a plurality of mixing elements having no moving parts are fixed (tubular reactor having a static mixing element). It is. Preferably, continuous polymerization in a high polymer concentration region, which has not been achieved so far, can be performed by continuously performing bulk polymerization or solution polymerization while performing static mixing in a tubular reactor. Also, high thermal conductivity is achieved by the combination with a large internal heat exchange surface, so that it is possible to carry out a very rigid exothermic polymerization reaction under thermal control without the possibility of forming hot spots. Furthermore, the tubular reactor having the static mixing structure part preferably has a composite curved tube for the purpose of increasing the heat exchange surface area and improving the mixing property. The heat transfer area per unit volume of the tubular reactor used in the present invention is preferably 10 m ² / m ³ or more, more preferably 30 m ² / m ³ or more, and still more preferably 50 m ² / m ³ or more. is there.

  In the tubular reactor having the static mixing structure in the present invention, the temperature distribution in the pipe during polymerization represented by the relational expression of (inner temperature−wall temperature) / (average inner temperature−wall temperature) is 0 to 0. Preferably it is 1.2. If the temperature distribution is 1.2 or more, the heat conduction efficiency is poor, hot spots may be formed, and thermal control of the polymerization reaction may be difficult.

  As the plurality of mixing elements fixed inside the tubular reactor having the structure for static mixing, for example, the division and flow direction of the polymerization liquid flowing into the pipe are changed, and the division and merging are repeated. The tubular reactor is preferably a static mixer, such as an SMX type or SMR type sulzer type tubular mixer, Kenix Type static mixer, Toray type tubular mixer and the like. Particularly, SMX type and SMR type sulzer type tubular mixers are preferable.

The tubular reactor having the static mixing structure in the present invention includes at least one static mixing structure in which the liquid heat transfer medium flows through the internal coil in order to increase the effective reaction volume. It is preferably composed of at least one reactor arranged. One or two or more reactors are used, and two or more reactors can be combined as necessary.

The pressure inside the tubular reactor having the static mixing structure during polymerization is preferably equal to or higher than the vapor pressure of the reaction solution. The pressure inside the tubular reactor is preferably 1 to 40 kg / cm ² G and not less than the vapor pressure of the reaction solution. By maintaining the inside of the reactor at 1 to 40 kg / cm ² G and at or above the vapor pressure of the reaction solution, foaming of the reaction solution can be suppressed and blockage due to foaming can be prevented.

  In the present invention, more preferably, as the loop reactor in the step (a), a mixed solution that refluxes in a circulating loop reactor having at least one tubular reactor having a static mixing structure. The flow rate of the mixed solution flowing out from the loop reactor in step (a) into the (b) extrusion flow reactor arranged in series with the reactor of the completely mixed flow is F2 (Fl (hour / hour)). In the case of (liter / hour), the reflux ratio (R = F1 / F2) is preferably in the range of 5-30. If the reflux ratio is less than 5, a polymerization degree distribution is generated in the loop reactor, and the function as a complete mixer which is the object of the present invention is not achieved. Further, if the reflux ratio exceeds 30, the residence time in the loop reactor becomes longer and there is a risk of runaway polymerization, and a large-scale capital investment is required to circulate a large amount of the polymerization solution. . In addition, by making the reflux ratio constant within the range of 5 to 30, uniform mixing is possible and a homogeneous polymerization solution is obtained, which is more preferable.

  In order to adjust the flow rate of the mixed solution that circulates in the circulating loop reactor composed of one or more tubular reactors having a static mixing structure, the circulating loop reactor is used for circulation. The pump can be provided. Since the circulation pump used here has a high viscosity of the polymerization solution, it is preferable to adjust the flow rate of the polymerization solution using a known gear pump.

  As the aromatic vinyl monomer (a1) contained in the monomer mixture (a) in the step (a), styrene, α-methylstyrene, p-methylstyrene, vinyltoluene, t-butylstyrene, o- Examples thereof include ethyl styrene, o-chlorostyrene, o, p-dichlorostyrene, or a mixture of two or more thereof, and styrene and α-methylstyrene are particularly preferably used.

  Examples of the vinyl cyanide monomer (a2) contained in the monomer mixture (a) include acrylonitrile, methacrylonitrile, ethacrylonitrile, or a mixture of two or more thereof, and acrylonitrile is particularly preferable. Used.

  The monomer mixture (a) is composed of an aromatic vinyl monomer (a1) and a vinyl cyanide monomer (a2), and an aromatic vinyl monomer (a1) and cyan. It may contain a vinyl fluoride monomer (a2) and another monomer (a3) copolymerizable therewith. Other monomers (a3) include unsaturated carboxylic acids such as acrylic acid and methacrylic acid, unsaturated carboxylic acid alkyl esters such as methyl acrylate and methyl methacrylate, unsaturated dicarboxylic acids such as maleic acid, and maleic anhydride. Examples thereof include unsaturated dicarboxylic anhydrides such as acids, N-substituted maleimides such as N-phenylmaleimide, and unsaturated amides such as acrylamide, but unsaturated carboxylic acid alkyl esters are preferred, and methyl methacrylate is more preferred. In addition, 1 type (s) or 2 or more types may be used for another monomer (a3).

  The monomer mixture (a) in the step (a) is 5 to 100% by weight of the aromatic vinyl monomer (a1) and 0 to 60% by weight of the vinyl cyanide monomer (a2) from the viewpoint of color tone and physical property balance. % And other monomers copolymerizable therewith (a3) are preferably 0 to 80% by weight, more preferably aromatic vinyl monomer (a1) 20 to 90% by weight, vinyl cyanide monomer It is 1 to 45% by weight of the monomer (a2) and 0 to 75% by weight of the other monomer (a3) copolymerizable therewith.

  In the present invention, it is preferable that the monomer mixture (a) is continuously supplied to the loop reactor in the step (a) and added during the process of continuous bulk polymerization or continuous solution polymerization.

  (A) When continuous solution polymerization is selected as the polymerization reaction in the step, a solvent is used in addition to the above monomer. The solvent used can contain saturated water. When a solvent is used, examples of the solvent include hydrocarbon solvents such as toluene, ethylbenzene, and xylene, polar solvents such as methyl ethyl ketone, methyl isobutyl ketone, butyl alcohol, and tetrahydrofuran. Among these, polar solvents More preferred is a solvent having a ketone group such as methyl ethyl ketone or methyl isobutyl ketone, and still more preferred is methyl ethyl ketone from the solubility of the copolymer (A). The organic solvent supplied to the complete mixing tank is preferably a polar solvent. (A) The amount of the organic solvent supplied to the loop reactor in the step is preferably 1 to 50 parts by weight, more preferably 100 parts by weight when the total amount of monomers added in all steps of the present invention is 100 parts by weight. 1-30 parts by weight, even more preferably 1-20 parts by weight of solvent is used.

  In the step (a), the monomer mixture (a) containing the aromatic vinyl monomer (a1) and the vinyl cyanide monomer (a2) is continuously supplied to the loop reactor, It is preferable to make it react until the polymerization rate of a polymer (A) becomes 20 to 75 weight%. In a more preferred embodiment, the polymerization rate of the copolymer (A) is 30 to 75% by weight. When the degree of polymerization of the copolymer (A) is less than 20% by weight or more than 75% by weight, it is difficult to control the polymerization reaction, and the copolymer (A) having a preferable composition described later may not be obtained. There is.

  As a method for adjusting the polymerization rate of the copolymer (A) in the step (a), a known polymerization technique can be applied. By changing the reactor residence time, polymerization temperature, and initiator concentration, it is possible to adjust the polymerization rate to the target. When the polymerization rate is lowered, it can be adjusted by shortening the reactor residence time, increasing the polymerization solvent, and lowering the polymerization temperature and the initiator concentration. The polymerization rate can be increased by extending the reactor residence time, decreasing the polymerization solvent, and increasing the polymerization temperature and initiator concentration.

  (A) It is preferable that the polymerization solution viscosity of the copolymer (A) in a process is 50-3000 poise, More preferably, it is 100-2000 poise. If it is less than 50 poise, the pumping stability for circulation is lowered, and particularly when an SMX type or SMR type sulzer type tubular mixer is used, there is a possibility that a completely mixed flow state cannot be maintained. If it exceeds 3000 Poise, the viscosity of the polymerization solution in the reactor increases, which may lead to failure of the circulation pump and the supply pump for maintaining a completely mixed flow state.

  (A) As for the polymerization temperature in a process, 70-120 degreeC is preferable, More preferably, it is 90-115 degreeC. When the polymerization temperature is 70 ° C. to 120 ° C., the amount of unreacted acrylonitrile is reduced.

  (A) The average residence time of the reaction liquid in the loop reactor of the process is determined by the target polymerization rate, polymerization temperature, type and amount of initiator used, and is preferably in the range of 0.5 to 4 hours. More preferably, it is 1 to 3 hours. By setting it within this range, the polymerization control is stabilized and the desired copolymer can be produced. If the residence time is shorter than 0.5 hour, it is necessary to increase the amount of radical polymerization initiator used, and it may be difficult to control the polymerization reaction.

  In the present invention, as the step (b), the polymerization solution containing the copolymer (A) obtained in the step (a) is extruded and supplied to the flow reactor to further polymerize the copolymer (A). It is also one of the preferable aspects to have the process of manufacturing a copolymer (B). (B) By having a process, the composition distribution of the vinyl cyanide compound of the copolymer can be broadened.

  (B) Various types of tube-type and column-type reactors can be used as the extruded flow reactor. A kneader reactor, a twin screw extruder, or the like can also be used as the polymerization reactor. These reactors can be used alone or in combination of two or more, and can be used by combining two or more types of reactors as necessary. In particular, it is preferable to use an in-line plug flow reactor comprising at least one tubular reactor having a static mixing structure as the extrusion flow reactor. In addition, although the specification in the (a) process is applied preferably, the tubular reactor which has the structure part for static mixing used preferably at the (b) process does not need to be the same. Further, the pressure inside the tubular reactor having the static mixing structure portion preferably used in the step (b) is preferably the same as the pressure condition in the step (a), but the steps (a) and ( B) The pressure conditions in the process need not be the same.

  The operation of withdrawing the copolymer (A) from the loop reactor in the step (a) and feeding it to the extrusion flow reactor in the step (b) can be performed by a pump, for example. The pump is preferably a commercially available gear pump. By extracting the reaction solution with the pump, the reaction solution can be sent stably to the next step, and the pressure of the extrusion flow reactor installed subsequently can be raised to the vapor pressure or higher of the reaction solution.

  Furthermore, in the present invention, in addition to the polymerization solution from the loop reactor in the step (b), the monomer mixture (b), various organic solvents, a polymerization initiator, Chain transfer agents, antioxidants, and heat stabilizers can be supplied. In particular, the composition distribution of the vinyl cyanide compound of the copolymer can be further broadened by the step of supplying the monomer mixture (b) to the extruded flow reactor of the step (b) (step (e)).

  In the step (e), the monomer mixture (b) supplied to the extrusion flow reactor in the step (b) includes the aromatic vinyl monomer (b1), the vinyl cyanide monomer (b2), and these. The other monomer (b3) which can be copolymerized can be contained.

  (E) Aromatic vinyl monomers (b1), vinyl cyanide monomers (b2) and other monomers copolymerizable with these (b3) contained in the monomer mixture (b) in step (e) Are the same as the aromatic vinyl monomer (a1), the vinyl cyanide monomer (a2) and the other monomer (a3) copolymerizable therewith in the step (a). preferable. The aromatic vinyl monomer (b1), the vinyl cyanide monomer (b2) and the other monomer (b3) copolymerizable therewith can be used alone or in combination of two or more.

  The composition ratio of the monomer mixture (b) in the step (e) is from 1 to 65% by weight of the aromatic vinyl monomer (b1) and vinyl cyanide monomer (b2) 1 from the viewpoint of balance of physical properties. It is preferably a vinyl monomer mixture consisting of ˜35% by weight and 0-80% by weight of other monomer (b3) copolymerizable therewith.

  The supply amount of the monomer mixture (b) in the step (e) is preferably 0 to 50% by weight when the total of the monomer mixture (a) and the monomer mixture (b) is 100% by weight. is there.

  In the step (e), the organic solvent supplied to the extrusion flow reactor in the step (b) is preferably a polar solvent. The organic solvent may be the same as or different from the organic solvent supplied to the loop reactor in the step (a), but is supplied to the loop reactor from the ease of volatile separation. It is preferable to use an organic solvent equivalent to the organic solvent. (B) The amount of the organic solvent supplied to the extrusion flow reactor is preferably 0 to 50 parts by weight, more preferably, when the total amount of monomers added in all steps of the present invention is 100 parts by weight. 0-30 parts by weight, even more preferably 0-20 parts by weight of solvent are used.

  In the step (e), the method of adding the monomer mixture (b), various organic solvents, polymerization initiator, chain transfer agent, antioxidant, and heat stabilizer to be supplied to the extrusion flow reactor in step (b), A method of adding from a side line adjacent to the tubular reactor inlet or a method of premixing with a static mixer separately arranged in series at the tubular reactor inlet and passing through the extrusion flow reactor in the step (b) is preferable.

  (B) It is preferable to make it react until the polymerization rate of the copolymer (B) in a process becomes 40 to 90 weight%, More preferably, it is 45 to 85 weight%. Here, as a method of adjusting the polymerization rate of a copolymer (B), it can adjust by the method of adjusting the polymerization rate in the said copolymer (A).

  The viscosity of the copolymer (B) in the step (b) is preferably 50 to 5000 poise, more preferably 300 to 4000 poise. If it is less than 50 poise, especially when an SMX-type or SMR-type sulzer-type tubular mixer is used, the division of the flow of the polymerization liquid flowing into the pipe and the direction of the flow are changed, and the turbulence is caused by repeating the division and merging. A stream may be formed and mixing of the polymerization solution may be difficult. If it exceeds 5000 Poise, the viscosity of the polymerization solution in the reactor increases, and the polymerization solution cannot be fed to the next step, which may lead to failure of the tubular mixer.

  (B) 70-200 degreeC is preferable, as for the polymerization temperature in a process, 90-180 degreeC is more desirable, More preferably, it is 100-160 degreeC. When the polymerization temperature is 70 ° C. or lower, the polymerization rate does not reach the present invention, the productivity cannot be ensured, and the composition distribution of the copolymer may be insufficient. In addition, when the temperature is 200 ° C. or higher, the reaction rate is remarkably increased, and the polymer (B) adheres as a scale to the structure for static mixing, which may cause problems in production stability.

  (B) The average residence time of the reaction liquid in the extrusion flow reactor in the step is preferably carried out in the range of 0.01 to 120 minutes. More preferably, it is 0.1 to 90 minutes, and if this average passage time is shorter than 0.01 minutes, the polymerization rate cannot be sufficiently increased. On the other hand, when the average passage time is longer than 120 minutes, the thermal stability of the finally obtained copolymer (B) is lowered, and the productivity may be lowered.

  In the steps (a) and (b) of the present invention, when the copolymers (A) and (B) are produced, thermal polymerization can be performed without using a polymerization initiator. It is possible to perform polymerization, and it is also possible to use thermal polymerization and initiator polymerization in combination. As the polymerization 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 cumyl peroxide, t-butyl peroxyacetate, t-butyl peroxybenzoate, t-butyl peroxyisopropyl carbonate, di-t-butyl peroxide, t-butyl peroctate, 1,1-bis (t-butylperoxy) 3,3,5-trimethyl Examples include cyclohexane, 1,1-bis (t-butylperoxy) cyclohexane, t-butylperoxy-2-ethylhexanoate, and the like.

  Specific examples of the azo compound include azobisisobutyronitrile, azobis (2,4dimethylvaleronitrile), 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-t-butylazo Examples include -1-cyanocyclohexane, 2-t-butylazo-2-cyanobutane, and 2-t-butylazo-2-cyano-4-methoxy-4-methylpentane.

  Among them, the polymerization initiator preferably has a 10-hour half-life temperature of 70 to 120 ° C., more preferably 80 to 100 ° C., and is a peroxide-based polymerization initiator 1,1′-bis. (T-Butylperoxy) cyclohexane is particularly preferably used.

  When using these polymerization initiators, 1 type (s) or 2 or more types can be used together. When using 2 or more types, it is preferable to use what has a 10-hour half-life temperature of 5 degreeC or more apart. As a result, the polymerization can proceed efficiently.

  The addition amount of the polymerization initiator is usually 0 to 1 part by weight with respect to 100 parts by weight of the total amount of monomers added in all steps of the present invention. When using a static mixing reactor in which the liquid heat transfer medium flows through the internal coil, the polymerization reaction can be controlled by the temperature of the liquid medium, not the polymerization initiator, so the amount of polymerization initiator added can be reduced. it can. Preferably, for the purpose of reducing the residual polymerization initiator, the addition amount of the polymerization initiator to be added is 0 to 0.1 parts by weight.

  In the steps (a) and (b) of the present invention, when the copolymers (A) and (B) are produced, alkyl mercaptan, carbon tetrachloride, carbon tetrabromide, dimethyl are used for the purpose of adjusting the degree of polymerization. It is preferable to add 0.05 to 0.2 parts by weight of a chain transfer agent such as acetamide, dimethylformamide, or triethylamine with respect to 100 parts by weight of the total amount of monomers. 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 in particular, n-octyl. Mercaptans, t-dodecyl mercaptans and n-dodecyl mercaptans are preferably used as chain transfer agents. When using these chain transfer agents, 1 type (s) or 2 or more types can be used together.

  In the present invention, as the step (c), the copolymer (A) obtained in the step (a) or the copolymer (B) obtained in the step (b) is at a temperature of 100 ° C. or more and less than 300 ° C., and the pressure is It is characterized by having a step of continuously devolatilizing at normal pressure (760 Torr) or less, and separating the unreacted raw material mixture and the copolymer to produce the copolymer (C).

  The step (c) is a step of separating and removing the unreacted raw material mixture and the copolymer by continuously devolatilizing, and the continuous devolatilizing apparatus for performing such devolatilization is uniaxial or A device equipped with a method for removing volatile components from a vent port under normal pressure or reduced pressure under heating with a twin-screw extruder, a method for removing volatile components with an evaporator incorporating a plate fin type heater such as a centrifugal type in a drum , Equipment equipped with a method of removing volatile components with a thin film evaporator such as a centrifugal type, and preheated using a heat exchanger, foamed, and flushed to at least one vacuum chamber to volatile components There are devices equipped with a method for removing water, and any of these devices can be used. In particular, the heat decomposition of the copolymer can be suppressed and the equipment is preheated and foamed using a heat exchanger that has low equipment costs. Flush to vacuum chamber It is preferably a device including a method of removing volatile components Te. Moreover, when performing devolatilization by flashing using a vacuum tank, an apparatus having a method of installing a gear pump at the lower part of the tank is preferably used in order to continuously discharge the polymer from the vacuum tank.

  The preheating and devolatilization temperature for continuous devolatilization are 100 or more and less than 300 ° C, and preferably 120 or more and less than 280 ° C. When devolatilized at 100 or more and less than 300 ° C., the organic solvent which is an unreacted monomer or a polymerization solvent is sufficiently removed, and there is no thermal degradation, so the thermal stability of the resulting thermoplastic copolymer (C) Product quality is good.

  As a preheating method for continuous devolatilization, it is possible to use a single-screw or twin-screw extruder, but preferably, preheating using a heat exchanger is low in energy saving and capital investment, It is preferable for suppressing deterioration of the resin. As heat exchangers to be used, spiral type, plate type, double pipe type, multi-pipe cylindrical type, multi-cylindrical type, spiral pipe type heat exchanger, static mixer used in (b) and (b) processes Although it can be used, multi-tubular heat exchange is preferred. It is also possible to inject a foaming agent into the heat exchanger in order to flush in a subsequent vacuum tank and remove volatile components.

  The average residence time of the copolymer in the continuous devolatilizer is preferably 5 to 60 minutes, more preferably 10 to 45 minutes. In addition, two or more continuous devolatilizers can be used as long as the object of the present invention is not impaired.

  (C) In the devolatilization step, the pressure is preferably normal pressure (760 Torr) or less, more preferably 200 Torr or less, more preferably 100 Torr or less, and further preferably 50 Torr or less. Is most preferred. The lower limit of the pressure is preferably 0.1 Torr or more. When the pressure in the devolatilization step is 200 Torr or less, the unreacted monomer or the mixture of the unreacted monomer and the polymerization solvent can be separated and removed efficiently, and the heat of the resulting thermoplastic copolymer (C) Good stability and quality.

  (C) The smaller the amount of residual monomer after the step, the better from the viewpoint of thermal stability and product quality. That is, the amount of residual monomer in the copolymer (C) is preferably 10% or less, more preferably 5% or less.

  (C) It is preferable that the unreacted monomer removed in the step or the mixture of the unreacted monomer and the organic solvent is recovered and recycled in the polymerization step. Since the volatile component is vaporized in the devolatilization step in a reduced pressure heating state, the volatile component is recovered by passing it through a known cooling device such as a condenser-equipped distiller and recovering the volatile component as a liquid. The whole amount can be recycled again in the polymerization step as it is. Further, the volatile component recovered in a liquid state can be recycled in a polymerization step after being purified by distillation using a known distillation apparatus, if necessary.

  In the present invention, the rate at which the copolymer (C) is produced in the step (c) from the monomers added in all steps, that is, the polymer production rate is preferably 10% / h or more. If the polymer production rate is less than 10% / h, the productivity may be lowered and the merit of continuous polymerization may be reduced.

  In the present invention, the copolymer (C) obtained in the step (c) as the step (d) is added to the aromatic vinyl monomer (d1) and the vinyl cyanide monomer in the presence of the rubbery polymer. A rubber-reinforced thermoplastic resin is obtained by continuously adding a graft copolymer (D) obtained by graft polymerization of a monomer mixture (d) containing (d2) and mixing them in a molten state (melt kneading). It is characterized by producing a composition.

  The rubbery polymer constituting the graft copolymer (D) in the step (d) of the present invention is a diene rubber, an acrylic rubber, an ethylene rubber or the like, and specific examples thereof include polybutadiene, poly (butadiene -Styrene), poly (butadiene-acrylonitrile), polyisoprene, 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) and the like. These rubbery polymers are used in one kind or a mixture of two or more kinds. Of these rubbery polymers, diene rubbers are preferably used, and among the diene rubbers, polybutadiene, poly (butadiene-styrene), poly (butadiene-acrylonitrile), and ethylene-propylene rubber are particularly preferably used.

  The aromatic vinyl monomer (d1) and the vinyl cyanide monomer (d2) constituting the monomer mixture (d) which is a raw material of the graft copolymer (D) in the step (d) are respectively ( It is preferable that they are the same as the aromatic vinyl monomer (a1) and the vinyl cyanide monomer (a2) in step a). The monomer mixture (d) is composed of an aromatic vinyl monomer (d1) and a vinyl cyanide monomer (d2), an aromatic vinyl monomer (d1), and cyan. It may contain a vinyl fluoride monomer (d2) and other monomers (d3) copolymerizable therewith. The other monomer (d3) is preferably the same as the other monomer (a3) in the step (a). The aromatic vinyl monomer (d1), the vinyl cyanide monomer (d2) or the other monomer (d3) copolymerizable therewith can be used alone or in combination.

  The ratio of the rubber-like polymer in the graft copolymer (D) is 5 to 80 parts by weight, more preferably 20 to 70 parts by weight, from the viewpoint of mechanical strength, color tone and moldability of the resin composition obtained. It is. The monomer mixture (d) is used in an amount of 5 to 100% by weight of the aromatic vinyl monomer (d1), 0 to 60% by weight of the vinyl cyanide monomer (d2), and copolymerized therewith. The other possible vinyl monomer (d3) is preferably 0 to 80% by weight, and more preferably 20 to 90% by weight of aromatic vinyl monomer (d1) from the viewpoint of balance of physical properties. It is 1 to 45% by weight of the vinyl monomer (d2) and 0 to 75% by weight of the other vinyl monomer (d3) copolymerizable therewith.

  Although there is no restriction | limiting in the manufacturing method of a graft copolymer (D), Preferably it manufactures by emulsion polymerization or block polymerization, More preferably, it manufactures by emulsion polymerization. Usually, emulsion polymerization is carried out by emulsion graft polymerization of a monomer mixture in the presence of a rubbery polymer latex. There is no particular limitation on the emulsifier used in this emulsion graft polymerization, and various surfactants can be used, but anionic surfactants such as carboxylate type, sulfate ester type and sulfonate type are particularly preferably used. The Specific examples of such emulsifiers include caprylate, caprate, laurate, misty phosphate, palmitate, stearate, oleate, linoleate, linolenate, rosinate, Behenate, castor oil sulfate, lauryl alcohol sulfate, other higher alcohol sulfate, dodecylbenzenesulfonate, alkylnaphthalenesulfonate, alkyldiphenyl ether disulfonate, polyoxyethylene lauryl sulfate, etc. Is mentioned. The salt here is an alkali metal salt, an ammonium salt or the like, and specific examples of the alkali metal salt include potassium salt, sodium salt, lithium salt and the like. These emulsifiers are used alone or in combination of two or more. Examples of the initiator and chain transfer agent that can be used in these emulsion graft polymerizations include the initiators and chain transfer agents mentioned in the production of the copolymer (A) or (B), and the initiator is a redox system. Even used.

  The graft copolymer (D) produced by emulsion graft polymerization is then added with a coagulant to coagulate the latex and recover the graft copolymer (D). Acid or water-soluble salt is used as the coagulant, and specific examples thereof include sulfuric acid, hydrochloric acid, phosphoric acid, acetic acid, calcium chloride, magnesium sulfate, aluminum sulfate, aluminum ammonium sulfate, potassium aluminum sulfate, and sodium aluminum sulfate. It is done. These coagulants are used in one or a mixture of two or more. The solidified graft copolymer (D) is dehydrated and dried in advance and added to the copolymer (C) in a molten state.

  As described above, the graft copolymer (D) can also be produced by a bulk polymerization method. When the bulk polymerization method is used, it is possible to add the graft copolymer (D) in the molten state from the demonomer machine directly to the copolymer (C), or to isolate it in advance. Although it is possible to add the graft copolymer (D) to the copolymer (C), the graft copolymer is usually in a molten state from the demonomer machine in terms of preventing thermal deterioration and continuation of the process. More preferably, (D) is added directly.

The graft copolymer (D) is preferably graft-polymerized to the rubber-like polymer in the total amount of the monomer mixture (d). However, the graft copolymer (D) is grafted with the graft copolymer as long as the effects of the present invention are not impaired. It may be a mixture of uncopolymers. The graft ratio of the graft copolymer (D) is not limited, but preferably 5 to 150% by weight, more preferably 10 to 100% by weight. The graft ratio here is calculated by the following formula.
Graft ratio (% by weight) = (Graft branch weight / Rubber polymer weight) × 100.

  In the step (d), the graft copolymer (D) is continuously added to the copolymer (C) in a molten state, and then mixed, and for the first time, color tone, impact resistance, etc. An excellent resin composition is obtained.

  There is no restriction | limiting in particular in the continuous addition method of the graft copolymer (D) in (D) process, It is possible to add by arbitrary methods. Usually, various types of feeders such as a belt type feeder, a screw type feeder, a single screw extruder, a twin screw extruder and the like are used, and a single screw extruder and a twin screw extruder are particularly preferably used. These continuous addition devices are preferably those that can be quantified. Further, it is preferable that the continuous addition device has a heating device and the graft copolymer (D) is added in a semi-molten or molten state, so that the mixed state is improved. For this purpose, an extruder or the like having a heating device can be used.

  The mixing method of the copolymer (C) and the graft copolymer (D) in step (d) is not particularly limited, but from the viewpoint of color tone and impact resistance, Supply the copolymer (C) to a vented single or twin screw extruder, add the graft copolymer (D) to the melted copolymer (C) in the extruder, and then melt mix The method is preferably selected. Melt mixing may be performed at the time of addition mixing, or may be performed after the mixture is isolated, for example, during melt molding.

  In the step (d), when the copolymer (C) and the graft copolymer (D) are mixed, 10 to 95 parts by weight of the copolymer (C) in the molten state is added to 90 to 90 parts of the graft copolymer (D). It is preferable to add 5 parts by weight continuously, more preferably 70 to 5 parts by weight of the graft copolymer (D) is continuously added to 30 to 95 parts by weight of the copolymer (C). In this case, the addition of the graft copolymer (D) is performed at a point where the amount of residual monomer in the copolymer (C) is 10% or less, more preferably 5% or less. The rubber component is not deteriorated by the heat history during the operation, and the color tone and impact resistance, which are the characteristics of the present invention, are further improved, which is preferable.

  In addition, it is possible to manufacture a rubber-reinforced thermoplastic resin composition imparted with transparency having a total light transmittance of 50% or more by the manufacturing method of the rubber-reinforced thermoplastic resin composition of the present invention described so far. is there. In the case of imparting transparency to the rubber-reinforced thermoplastic resin composition by the production method of the present invention, the composition of the monomer mixture (a) in the step (a) is an aromatic vinyl monomer (a1) 5 to 70. % By weight, vinyl cyanide monomer (a2) 0 to 50% by weight and other monomers copolymerizable with these (a3) 30 to 95% by weight, preferably from the viewpoint of color tone and transparency To aromatic vinyl monomer (a1) 5 to 70% by weight, vinyl cyanide monomer (a2) 0 to 45% by weight and other monomers copolymerizable therewith (a3) 30 to 90% More preferably, it is% by weight. In addition, the composition of the monomer mixture (d), which is a raw material for the graft component of the graft copolymer (D) in the step (d), is in the same range as the composition ratio of the monomer mixture (a) from the viewpoint of transparency. It is preferable to be within.

  When imparting transparency to the rubber-reinforced thermoplastic resin composition by the production method of the present invention, the refractive index of the copolymer (C) in the step (c) is substantially (d) the graft copolymer (D) It is preferable that it is the same as or slightly different from the rubber-like polymer constituting the above. As a specific range, it is preferable to suppress the difference in refractive index between the copolymer (C) and the rubber-like polymer to 0.03 or less, and more preferably 0.01 or less. Further, the amount of the graft component consisting of the monomer mixture (d) of the graft copolymer (D) in the step (d) is substantially the same as or slightly different from the refractive index of the rubber-like polymer. It is preferable to adjust the composition of the body mixture (d). As a specific range, the difference in refractive index between the graft component and the rubbery polymer is preferably 0.03 or less, more preferably 0.01 or less.

  In addition, the production method of the present invention includes polyolefins such as vinyl chloride, polyethylene, and polypropylene, polyamides such as nylon 6 and nylon 66, polyethylene terephthalate, polybutylene terephthalate, polycyclohexanedimethyl terephthalate, and the like as long as the effects of the present invention are not impaired. By adding a step of adding polyester, polycarbonate and various elastomers, the performance as a molding resin can be improved. In addition, as required, antioxidants such as hindered phenols, sulfur-containing organic compounds, and phosphorus-containing organic compounds, thermal stabilizers such as phenols and acrylates, benzotriazoles, benzophenones, salicylates, etc. Various stabilizers such as UV absorbers, organic nickel-based and hindered amine-based light stabilizers, higher fatty acid metal salts, higher fatty acid amides and other lubricants, phthalates, phosphates and other plasticizers, poly Flame retardants / flame retardants such as bromodiphenyl ether, tetrabromobisphenol-A, brominated epoxy oligomers, brominated polycarbonate oligomers, etc., phosphorus compounds, antimony trioxide, antistatic agents, carbon black, oxidation Such as titanium, pigments and dyes, water, silicone oil, liquid paraffin, etc. It is also possible to add the step of adding the body. Furthermore, a step of adding a reinforcing agent or filler such as glass fiber, glass flake, glass bead, carbon fiber, or metal fiber can be added. There are no particular restrictions on the method of adding these additives, and it is also possible to add them continuously with the graft copolymer (D), and to add them as a subsequent step after isolating the mixture of (C) and (D). Various methods such as these can be used.

  Next, a preferred embodiment of the production method of the present invention will be described specifically by way of a process diagram of FIG. The plug flow reactor (II) described in the process diagram of FIG. 1 is an example of an extruded flow reactor of the step (b) used in the present invention.

  A circulation loop having tubular reactors (2) and (3) having a structure for static mixing of a raw material monomer, a radical initiator and a solvent, and a gear pump (4) by a plunger pump (1) To the reactor (I). In the circulation type loop reactor, the polymerization proceeds while the polymerization solution circulates, and a part of the polymerization solution is sent to the serial type plug flow reactor (II). Here, the ratio of the flow rate of the polymer solution circulating through the loop reactor and the flow rate of the polymer solution flowing out to the plug flow reactor, the reflux ratio R, does not flow into the plug flow reactor (II). The flow rate of the mixed solution refluxed in the loop reactor (I) is F1 (liter / hour), and the flow rate F2 (liter) of the mixed solution flowing out from the loop reactor (I) to the plug flow reactor (II). In general, R = F1 / F2 is preferably in the range of 5-30. Further, a vinyl monomer mixture (b), various organic solvents, a polymerization initiator, and a chain transfer agent are introduced from the side line (5) located at the connection portion from the loop reactor to the plug flow reactor. be able to.

  Next, the polymerization solution that has flowed out into the plug flow reactor (II) passes through the tubular reactors (6) and (7) having the static mixing structure inside, thereby allowing further polymerization. proceed. Next, it is sent to a devolatilizer (III) consisting of a preheater (8) and a vacuum tank (9), and unreacted monomers and solvent are flushed to the vacuum tank under reduced pressure to remove volatile components. After that, in the twin screw extruders (11) and (12) discharged from the gear pump (10) and having a vent, the copolymer (C) in the molten state is grafted from the twin screw extruder type feeder (13). The target rubber reinforcement by melting and mixing in compounding apparatus (IV) into which coalescence (D), known plasticizer, heat stabilizer, antioxidant, light stabilizer and the like are introduced, and then discharged and pelletized. A thermoplastic resin composition is obtained.

  EXAMPLES Hereinafter, although an Example is given and this invention is further explained in full detail, this invention is not limited to these Examples.

(1) Polymerization rate The unreacted monomer concentration (wt%) in the polymerization solution and the charged raw material solution was quantified by a gas chromatograph and calculated from the following equation.
Polymerization rate = 100 × (1-M1 / M0)
In addition, each symbol in a formula shows the following numerical value.
M1 = Unreacted monomer concentration in the polymerization solution (wt%)
M0 = monomer concentration (wt%) in the charged raw material solution.

(2) Polymer production rate The supply amount of the reaction monomer monomers (a) and (b) is X1 (kg / h), and the discharge amount of the copolymer (C) discharged from the devolatilizer is X2 (kg). / H), and the total residence time of the monomer and copolymer in the complete mixing tank, tubular reactor, and devolatilizer was τ (h), and was calculated from the following equation.
Reaction rate (% / h) = (X2 / X1) / τ.

(3) Reduced Viscosity Using a Ubbelohde viscometer, it was measured from a methyl ethyl ketone solution having a measurement temperature of 30 ° C. and a sample concentration of 0.4 g / dl.

(4) Polymer composition A sample was formed into a film of about 40 μm by a heating press and obtained by an infrared spectrophotometer.

(5) Haze value and total light transmittance Square pellet molded product formed by immediately filling pellets dried for 3 hours in a hot air dryer at 80 ° C. into an IS50A molding machine manufactured by Toshiba Corporation set at a cylinder temperature of 250 ° C. The total light transmittance (thickness 3 mm) and the haze value [%] were measured using a direct reading haze meter manufactured by Toyo Seiki Co., Ltd.

(6) Graft rate Acetone is added to the rubber-containing graft copolymer (weight M) and refluxed for 3 hours. The solution is centrifuged for 40 minutes, the insoluble matter is filtered, and the insoluble matter is vacuum-dried at 60 ° C. for 5 hours. The weight N was measured. The graft ratio was determined by the following formula. In the formula, L is the rubbery polymer content (%) in the rubber-containing graft copolymer.
Graft ratio (% by weight) = 100 × (MN−L / 100) / (M × L / 100).

(7) Color tone (YI value)
After molding the rubber-reinforced thermoplastic resin composition at 230 ° C., the obtained molded product was evaluated according to JIS K7105 (1981 established), 6.3 Yellowness Yellowing Measurement Method.

(8) Charpy impact strength The rubber-reinforced thermoplastic resin composition was injection molded, and the resulting molded product was measured for Charpy impact strength according to ISO179.

(9) Fluidity (MFR)
According to ISO 1133, MFR of 10 kg of 220 degreeC load was measured for the rubber-reinforced thermoplastic resin composition.

(10) Bleed amount After 15 g of rubber-reinforced thermoplastic resin composition pellets were dried at 80 ° C. for 3 hours, they were laid flat on a 270 ° C. heat plate disposed at the bottom. The gap of the upper plate was adjusted to 4 mm using a spacer, and after heating for 10 minutes, the upper plate was removed. The bleed material adhering to the upper plate was weighed, and the bleed amount (% by weight) contained in 15 g of the sample was determined.

(11) Residual monomer amount After 1.5 g of rubber-reinforced thermoplastic resin pellets were dissolved in 30 g of acetone, the unreacted monomer concentration (wt%) was quantified by gas chromatography and calculated as the residual monomer amount. did.

(12) Refractive Index Calculation Method The refractive index of the rubbery polymer is a known value. On the other hand, regarding the refractive index of the graft component of the copolymer (A) and the graft copolymer (D), from the refractive index in the polymer of each monomer and the composition of the copolymer, Calculated.
Refractive index = 1.51 x (AN composition (wt%) / 100) + 1.595 x (ST composition (wt%) / 100) + 1.49 x (MMA composition (wt%) / 100).

(Reference Example 1) (Method for producing graft copolymer)
50 parts by weight of polybutadiene latex (rubber particle size: 0.3 μm, gel content: 85%, refractive index: 1.52), 200 parts by weight of pure water, 0.4 parts by weight of sodium formaldehyde sulfoxylate, ethylenediamine tetra Sodium acetate 0.1 parts by weight, ferrous sulfate (0.01 parts by weight) and sodium phosphate 0.1 parts by weight were charged into a reaction vessel, and after nitrogen substitution, the temperature was adjusted to 65 ° C., and 35 parts by weight of styrene with stirring. A mixture of 15 parts by weight of acrylonitrile and 0.3 parts by weight of n-dodecyl mercaptan was continuously added dropwise over 4 hours. At the same time, a mixture of 0.25 parts by weight of cumene hydroperoxide, 2.5 parts by weight of sodium laurate as an emulsifier and 25 parts by weight of pure water was continuously added dropwise over 5 hours. The polymerization was terminated. The latex after completion of polymerization was coagulated with 1.5% sulfuric acid, then neutralized with alkali, washed, centrifuged, and dried to prepare a graft copolymer (D-1) on powder.

(Reference Examples 2 to 4) (Method for producing graft copolymer)
In the same manner as in Reference Example 1, a graft copolymer (D-) having the composition shown in Table 1 was obtained by polymerizing a mixture of styrene and other vinyl monomers in the presence of each rubbery polymer shown in Table 1. 2-4) were produced. In Table 1, PBD is the same polybutadiene rubber as used in Reference Example 1, SBR is styrene / butadiene copolymer rubber composed of 25% by weight of styrene and 75% by weight of butadiene (rubber particle diameter 0.3 μm, gel NBR is an acrylonitrile / butadiene copolymer rubber composed of 25% by weight of acrylonitrile and 75% by weight of butadiene (rubber particle diameter 0.3 μm, gelation rate 70%, refractive index 1). EPDM is an ethylene / propylene / 5-ethylidene-2-norbonene terpolymer rubber having an iodine value of 23 and a Mooney viscosity of 60 (ethylene / propylene = 68.5 / 31.5 molar ratio) (rubber particles) The diameter is 0.3 μm, the gelation rate is 70%, and the refractive index is 1.48).

(Reference Example 5) (Method for producing graft copolymer)
Polybutadiene latex (rubber particle system 0.3 μm, gel content 85%) 50 parts by weight (in terms of solid content), pure water 180 parts by weight, sodium formaldehyde sulfoxylate 0.4 parts by weight, sodium ethylenediaminetetraacetate 0.1 parts by weight Parts, 0.01 parts by weight of ferrous sulfate and 0.1 parts by weight of sodium phosphate were charged into a reaction vessel, and after nitrogen substitution, the temperature was adjusted to 65 ° C., with stirring, 11.5 parts by weight of styrene, 4.0 of acrylonitrile. A mixture of parts by weight, 34.5 parts by weight of methyl methacrylate and 0.3 parts by weight of n-dodecyl mercaptan was continuously added dropwise over 4 hours. Simultaneously, a mixture of 0.25 parts by weight of cumene hydroperoxide, 2.5 parts by weight of sodium oleate as an emulsifier and 25 parts by weight of pure water was continuously added dropwise over 5 hours. After completion of the addition, the mixture was further maintained for 1 hour. The polymerization was terminated. The latex product after the polymerization was coagulated by pouring into 2000 parts by weight of 95 ° C. water to which 1.0 part by weight of sulfuric acid was added, and then neutralized with alkali, washed, centrifuged and dried. Then, a graft copolymer (D-5) on the powder was prepared.

(Reference Example 6) (Method for producing graft copolymer)
The graft copolymer (D-6) was prepared in the same manner as in Reference Example 5 except that SBR was used as the rubbery polymer, and 22 parts by weight of styrene, 3 parts by weight of acrylonitrile, and 23 parts by weight of methyl methacrylate were used as the graft component. )

(Reference Example 7) (Method for producing graft copolymer)
After dissolving 10 parts by weight of diene NF35A in 90 parts by weight of a monomer mixture composed of 70% by weight of styrene and 30% by weight of acrylonitrile, continuous bulk polymerization / demonomerization was carried out to obtain a graft copolymer (D-7 )

Example 1
1 was continuously fed from the plunger pump (1) at a rate of 6 kg / h using the continuous polymerization apparatus shown in FIG. The loop reactor (I) is a tubular reactor having an inner diameter of 2.5 inches (30 built-in SMX type static mixer / static mixing element manufactured by Gebrüter Sulzer, Switzerland, heat transfer area 130 m ² / m ³ ) (2 ), (3) and a gear pump (4) for circulating the mixed solution. The reflux ratio (R = F1 / F2) was 20. Polymerization temperature of the loop reactor (I) was 110 ° C., the inner wall temperature of the reactors (2) and (3) was 115 ° C., and an average residence time was 1.5 hours. The polymerization rate was 70% by weight.

Acrylonitrile 40.0% by weight
Styrene 60.0% by weight
(Hereinafter, 100 parts by weight of the total amount of monomers added in all steps)
1,1′-bis (t-butylperoxy) cyclohexane 0.005 parts by weight n-octyl mercaptan 0.20 parts by weight.

  An in-line plug flow reactor (II) which is an extrusion flow reactor is composed of 2.5 inch inner diameter tubular reactors (6) and (7), and the tubular reactors (6) and (7). The inner wall temperature was 130 ° C., the polymerization temperature was 130 ° C., and the residence time was 30 minutes. The polymerization rate of the polymerization solution at the outlet of the tubular reactor (7) was 85% by weight.

  Subsequently, as a devolatilization step, the polymerization solution was supplied to a heat exchanger (8) heated to 260 ° C. and a vacuum tank (9), and devolatilization was performed at a pressure of 20 Torr for 30 minutes. It was 2.5 hours.

  After devolatilization, as a step of melt-kneading the graft copolymer, the molten polymerization reaction mixture is supplied to a single-screw extruder with a vent, and the apparent polymerization rate is 99% at 1/3 from the tip of the extruder. To the styrene / acrylonitrile copolymer raised above, a phenol-based stabilizer t-butylhydroxytoluene 0.006 kg / hour and a phosphorus-based stabilizer tri (nonylphenyl) phosphite from a twin-screw extruder type feeder The graft copolymer (B-1) produced in Reference Example 1 together with 0.006 kg / hour is supplied in a semi-molten state at a rate of 2.6 kg / hour, melt-kneaded, and then pelletized rubber-reinforced thermoplastic resin. A composition (E-1) was obtained.

  The detailed production conditions of the rubber-reinforced thermoplastic resin composition other than the above are as shown in Table 2.

  The amount of the obtained polymer was 8.6 kg / h, and the polymer production rate was 28% / h. Table 3 shows the results obtained by molding an injection-molded piece of the obtained rubber-reinforced thermoplastic resin composition (E-1) and measuring the physical properties.

(Example 2)
Except for not using the serial plug flow reactor (II) which is an extrusion flow reactor, the styrene / acrylonitrile was recovered by evaporating the unreacted monomer under reduced pressure using a continuous bulk polymerization / devolatilization apparatus in the same manner as in Example 1. After melt-kneading the styrene / acrylonitrile copolymer and the graft copolymer with a vented single-screw extruder, the styrene / acrylonitrile copolymer and the graft copolymer were discharged in a strand shape to obtain rubber-reinforced thermoplastic resin composition (E-2) pellets. Table 3 shows the YI value of the obtained rubber-reinforced thermoplastic resin composition and the physical property measurement results of the test piece obtained by injection molding the resin composition.

(Example 3)
A rubber-reinforced thermoplastic resin composition (E-3) pellet was obtained in the same manner as in Example 2 except that the composition of the monomer mixture shown below and the number of added parts of the graft copolymer were 15 parts by weight. . Table 3 shows the YI value of the obtained rubber-reinforced thermoplastic resin composition and the physical property measurement results of the test piece obtained by injection molding the resin composition.

Acrylonitrile 30.0% by weight
Styrene 70.0% by weight
(Hereinafter, 100 parts by weight of the total amount of monomers added in all steps)
1,1′-bis (t-butylperoxy) cyclohexane 0.003 parts by weight n-octyl mercaptan 0.20 parts by weight.

Example 4
Rubber reinforced heat was obtained in the same manner as in Example 2 except that 15 parts by weight of methyl ethyl ketone (MEK) was added to the monomer mixture, and the solution continuous polymerization with a residence time in the loop reactor of 2.0 hours was obtained. A plastic resin composition (E-4) pellet was obtained. Table 3 shows the YI value of the obtained rubber-reinforced thermoplastic resin composition and the physical property measurement results of the test piece obtained by injection molding the resin composition.

(Example 5)
Example 3 with the exception that the composition of the monomer mixture shown below and 15 parts by weight of MEK were added to the monomer mixture, resulting in solution continuous polymerization with a residence time in the loop reactor of 2.0 hours. A rubber-reinforced thermoplastic resin composition (E-4) pellet was obtained in the same manner. Table 3 shows the YI value of the obtained rubber-reinforced thermoplastic resin composition and the physical property measurement results of the test piece obtained by injection molding the resin composition.

Acrylonitrile 30.0% by weight
Styrene 70.0% by weight
(Hereinafter, 100 parts by weight of the total amount of monomers added in all steps)
1,1′-bis (t-butylperoxy) cyclohexane 0.003 parts by weight n-octyl mercaptan 0.20 parts by weight.

(Examples 6 to 9)
A rubber-reinforced thermoplastic resin composition in the same manner as in Example 2 except that the graft copolymer (D2-4) produced in Reference Examples 2-4 is supplied in a semi-molten state from a heated twin-screw extruder type feeder. (E-6-9) Pellets were obtained. Table 3 shows the YI value of the obtained rubber-reinforced thermoplastic resin composition and the physical property measurement results of the test piece obtained by injection molding the resin composition.

(Example 10)
A rubber-reinforced thermoplastic resin composition (E-10) pellet in the same manner as in Example 2 except that the composition of the monomer mixture shown below and the graft copolymer (D-5) are supplied in a semi-molten state Got. Table 3 shows the YI value of the obtained rubber-reinforced thermoplastic resin composition and the physical property measurement results of the test piece obtained by injection molding the resin composition.

Acrylonitrile 8.0% by weight
Styrene 23.0% by weight
Methyl methacrylate 69.0% by weight
(Hereinafter, 100 parts by weight of the total amount of monomers added in all steps)
1,1′-bis (t-butylperoxy) cyclohexane 0.003 parts by weight n-octyl mercaptan 0.20 parts by weight.

(Example 11)
The rubber-reinforced thermoplastic resin composition (E-11) pellets in the same manner as in Example 2 except that the composition of the monomer mixture shown below and the graft copolymer (D-6) are supplied in a semi-molten state. Got. Table 3 shows the YI value of the obtained rubber-reinforced thermoplastic resin composition and the physical property measurement results of the test piece obtained by injection molding the resin composition.

Acrylonitrile 10.0% by weight
Styrene 44.0% by weight
Methyl methacrylate 46.0% by weight
(Hereinafter, 100 parts by weight of the total amount of monomers added in all steps)
1,1′-bis (t-butylperoxy) cyclohexane 0.005 parts by weight n-octyl mercaptan 0.20 parts by weight.

(Example 12)
The rubber-reinforced thermoplastic resin composition (E-12) pellets were produced in the same manner as in Example 4 except that the composition of the monomer mixture shown below and the graft copolymer (D-5) were supplied in a semi-molten state. Got. Table 3 shows the YI value of the obtained rubber-reinforced thermoplastic resin composition and the physical property measurement results of the test piece obtained by injection molding the resin composition.

Acrylonitrile 10.0% by weight
Styrene 44.0% by weight
Methyl methacrylate 46.0% by weight
(Hereinafter, 100 parts by weight of the total amount of monomers added in all steps)
1,1′-bis (t-butylperoxy) cyclohexane 0.005 parts by weight n-octyl mercaptan 0.20 parts by weight.

(Example 13)
In the reactor (I), the polymerization is carried out with the following monomer mixture composition. In the reactor (II), the following monomer mixture is added, followed by polymerization, and the reactor (II ) A rubber-reinforced thermoplastic resin composition (E-13) pellet was obtained in the same manner as in Example 1 except that the residence time was 1.0 hour. Table 3 shows the YI value of the obtained rubber-reinforced thermoplastic resin composition and the physical property measurement results of the test piece obtained by injection molding the resin composition.

Composition of monomer mixture in reactor (I) Acrylonitrile 35.0% by weight
Styrene 50.0% by weight
(Hereinafter, 100 parts by weight of the total amount of monomers added in all steps)
1,1′-bis (t-butylperoxy) cyclohexane 0.005 parts by weight n-octyl mercaptan 0.20 parts by weight Composition of monomer mixture in reactor (II) Acrylonitrile 5.0% by weight
Styrene 10.0% by weight
(Hereinafter, 100 parts by weight of the total amount of monomers added in all steps)
1,1′-bis (t-butylperoxy) cyclohexane 0.0015 parts by weight Methyl ethyl ketone 15.0 parts by weight.

(Comparative Example 1)
As a continuous polymerization apparatus, a 2m ³ complete mixing type polymerization tank having a condenser for evaporation and recirculation of monomer vapor and a helical ribbon blade, a single-screw extruder type preheater, and a twin-screw extruder type demonomer and demonomer machine Polymerization and resin mixing were carried out using a continuous bulk polymerization apparatus composed of a twin-screw extruder type feeder having a heating device connected in tandem to a barrel portion 1/3 long from the tip.

  First, a monomer mixture having the following composition was continuously supplied to a polymerization tank at 6 kg / hour, and continuous bulk polymerization was performed while maintaining a polymerization temperature of 130 ° C. and a tank internal pressure of 0.08 MPa. The polymerization rate of the polymerization reaction mixture at the exit from the polymerization tank was controlled to 75% by weight.

Styrene 70.0% by weight
Acrylonitrile 30.0% by weight
(Hereinafter, 100 parts by weight of the total amount of monomers added in all steps)
n-octyl mercaptan 0.20 parts by weight 1,1′-bis (t-butylperoxy) cyclohexane 0.01 parts by weight.

  As a devolatilization process, the polymerization reaction mixture is preheated to 240 ° C. with a single screw extruder type preheater, and then unreacted monomer is evaporated from the vent port under a reduced pressure of 40 to 760 Torr by a twin screw type demonomer The recovered unreacted monomer was continuously refluxed to the polymerization tank. As a step of melt-kneading the graft copolymer, a biaxial styrene / acrylonitrile copolymer having an apparent polymerization rate increased to 99% or more at 1/3 from the exit end of the biaxial extruder type demonomer By using an extruder-type feeder, the graft co-polymer produced in the phenolic stabilizer t-butylhydroxytoluene 0.009 kg / hour, phosphorus stabilizer tri (nonylphenyl) phosphite 0.009 kg / hour and the reference example. A semi-molten product (1.1 kg / hour) of polymer (D-1) was supplied and melt-kneaded with a styrene / acrylonitrile copolymer in a demonomer machine. During the melt-kneading step, water was supplied at a rate of 1/8 from the outlet end of the demonomer machine at 0.08 kg / hour. The water and other volatile components were further removed by evaporation under a reduced pressure of 20 to 40 Torr from a vent port installed downstream of the demonomer. Thereafter, the molten polymer was discharged in a strand shape, and rubber-reinforced thermoplastic resin composition (E-14) pellets were obtained with a cutter.

  The detailed production conditions of the rubber-reinforced thermoplastic resin composition other than the above are as shown in Table 2.

  Table 3 shows the YI value of the obtained rubber-reinforced thermoplastic resin composition and the physical property measurement results of the test piece obtained by injection molding the resin composition.

(Comparative Example 2)
Comparative Example 1 except that the composition of the monomer mixture containing methyl ethyl ketone shown below, the number of added parts of the graft copolymer (D-1) is 15 parts by weight, and the residence time in the polymerization tank is 3.5 hours The rubber-reinforced thermoplastic resin composition (E-15) pellets were obtained by the method described above. Table 3 shows the YI value of the obtained rubber-reinforced thermoplastic resin composition and the physical property measurement results of the test piece obtained by injection molding the resin composition.

Styrene 60.0% by weight
Acrylonitrile 40.0% by weight
(Hereinafter, 100 parts by weight of the total amount of monomers added in all steps)
n-octyl mercaptan 0.20 parts by weight 1,1′-bis (t-butylperoxy) cyclohexane 0.015 parts by weight Methyl ethyl ketone 15 parts by weight.

(Comparative Example 3)
The composition of the monomer mixture shown below, except that the graft copolymer to be added is a graft copolymer (D-5) and the number of added parts of the graft copolymer (D-5) is 30 parts by weight. Rubber reinforced thermoplastic resin composition (E-16) pellets were obtained in the same manner as in Comparative Example 1. Table 3 shows the YI value of the obtained rubber-reinforced thermoplastic resin composition and the physical property measurement results of the test piece obtained by injection molding the resin composition.

Styrene 20.0% by weight
Acrylonitrile 20.0% by weight
Methacrylic acid methyl 60.0% by weight
(Hereinafter, 100 parts by weight of the total amount of monomers added in all steps)
n-octyl mercaptan 0.20 parts by weight 1,1′-bis (t-butylperoxy) cyclohexane 0.01 parts by weight.

(Comparative Example 4)
Rubber-reinforced thermoplastic resin composition (E-17) pellets were obtained in the same manner as in Comparative Example 3 except that the monomer mixture contained 15 parts by weight of methyl ethyl ketone and the residence time in the polymerization tank was 3.5 hours. . Table 3 shows the YI value of the obtained rubber-reinforced thermoplastic resin composition and the physical property measurement results of the test piece obtained by injection molding the resin composition.

  As shown in Table 3, the rubber-reinforced thermoplastic resin composition obtained by the production method of the present invention has a better physical property balance in color tone and impact resistance than the rubber-reinforced thermoplastic resin composition obtained by the comparative example, It was excellent. Moreover, compared with a comparative example, an Example is a process which does not generate | occur | produce a polymerization tank stirring power and a preheater electric power, and also the specific energy of the extruder type | mold demonomer machine with a vent of a comparative example is 0.05-0.10 kW / Whereas the specific energy of the extruder with a vent in the example is 0.02 to 0.04 kW / kg, the manufacturing method of the example was a power-saving process.

  The rubber-reinforced thermoplastic resin composition obtained in the present invention is expected to be used in many fields such as automobile members, home appliances and building materials.

(1) Pusher pump
(2) Tubular reactor with static mixing structure inside
(3) Tubular reactor with static mixing structure inside
(4) Gear pump
(5) Side line
(6) Tubular reactor with static mixing structure inside
(7) Tubular reactor with static mixing structure inside
(8) Preheater
(9) Devolatilizer
(10) Gear pump
(11) Devolatilizing extruder
(12) Vent port
(13) Feeder
(14) Base
(I) Loop reactor
(II) Plug flow reactor
(III) Devolatilizer
(IV) Compound device

Claims (14)

  (A) A monomer mixture (a) containing an aromatic vinyl monomer (a1) and a vinyl cyanide monomer (a2) is continuously fed to a loop reactor to obtain a copolymer (A) (C) The copolymer (A) is continuously devolatilized at a temperature of 100 ° C. or higher and lower than 300 ° C. and a pressure of normal pressure (760 Torr or lower) to separate the unreacted raw material mixture and the copolymer. And (d) the copolymer (C), the aromatic vinyl monomer (d1) and the vinyl cyanide monomer in the presence of the rubbery polymer. A rubber-reinforced thermoplastic resin composition characterized by continuously adding a graft copolymer (D) obtained by graft polymerization of a monomer mixture (d) containing (d2) and mixing in a molten state. Production method.   Unsaturated carboxylic acid as monomer (a3) copolymerizable with aromatic vinyl monomer (a1) and vinyl cyanide monomer (a2) in monomer mixture (a) in step (a) A monomer comprising an alkyl ester monomer and capable of copolymerizing with the aromatic vinyl monomer (d1) and the vinyl cyanide monomer (d2) in the monomer mixture (d) in the step (d). The method for producing a rubber-reinforced thermoplastic resin composition according to claim 1, comprising an unsaturated carboxylic acid alkyl ester monomer as the body (d3).   The rubber-reinforced thermoplastic resin according to claim 1 or 2, wherein the loop reactor in the step (a) is a circulation loop reactor composed of two or more tubular reactors. A method for producing the composition.   The loop reactor in the step (a) is a circulating loop reactor composed of one or more tubular reactors having a static mixing structure. A method for producing a rubber-reinforced thermoplastic resin composition according to any one of the above.   The rubber reinforcement according to any one of claims 1 to 4, wherein the step (c) is a step of removing volatile components by flushing the unreacted raw material mixture into at least one vacuum tank. A method for producing a thermoplastic resin composition.   The rubber-reinforced heat according to any one of claims 1 to 5, wherein in the step (c), devolatilization is performed until the amount of the unreacted raw material mixture of the copolymer (C) is 10% or less. A method for producing a plastic resin composition.   In the step (d), the graft copolymer (D) is continuously added to the copolymer (C) by a single-screw or twin-screw extruder with a vent connected to the copolymer (C) extruder. It is a process to extrude, The manufacturing method of the rubber reinforced thermoplastic resin composition in any one of Claims 1-6 characterized by the above-mentioned.   The method for producing a rubber-reinforced thermoplastic resin composition according to any one of claims 1 to 7, wherein in the step (d), the graft copolymer (D) is added in a semi-molten or molten state.   The method for producing a rubber-reinforced thermoplastic resin composition according to any one of claims 1 to 8, wherein in the step (d), the rubber-like polymer of the graft copolymer (D) is a diene rubber.   Between the step (a) and the step (c), (b) a polymerization solution containing the copolymer (A) obtained in the step (a) is supplied to an extruded flow reactor and the copolymer (A The method for producing a rubber-reinforced thermoplastic resin composition according to any one of claims 1 to 9, further comprising a step of supplying a copolymer (B) obtained by further polymerizing a copolymer (B) to the step (c).   The reactor of the extrusion flow in the step (b) is a serial plug flow reactor composed of one or more tubular reactors having a static mixing structure. A process for producing a rubber-reinforced thermoplastic resin composition as described in 1).   The production of a rubber-reinforced thermoplastic resin composition according to claim 10 or 11, wherein in the step (b), the reaction is carried out until the polymerization rate of the copolymer (B) reaches 40 to 90% by weight. Method.   Between the step (a) and the step (b), (e) a monomer containing the aromatic vinyl monomer (b1) in the polymerization solution containing the copolymer (A) obtained in the step (a) The manufacturing method of the rubber reinforced thermoplastic resin composition in any one of Claims 10-12 including the process of adding a body mixture (b). The method for producing a rubber-reinforced thermoplastic resin composition according to claim 4 or 11, wherein a heat transfer area per unit volume of the tubular reactor having the static mixing structure portion is 50 m ² / m ³ or more.

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