JP2895565B2 - Method and apparatus for producing thermoplastic resin - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method for producing a thermoplastic resin, particularly an ABS / MBS-based resin (hereinafter abbreviated as ABS resin, etc.) and an apparatus therefor. More specifically, an ABS resin is continuously produced by a graft polymer latex obtained by emulsion polymerization, a slurry of this Latec or a water-containing polymer, and a vinyl polymer in a molten state obtained by solution polymerization or / and bulk polymerization. And a device for manufacturing the same.

[Prior art] Conventionally, methods for producing ABS resins and the like include: 1) a method of producing a graft polymer obtained by an emulsion polymerization method and a vinyl polymer obtained by a suspension polymerization or bulk polymerization method; A method of producing from a graft polymer obtained by a synthetic method and a vinyl polymer obtained by an emulsion polymerization method 3) A graft polymer obtained by an emulsion polymerization method is mixed with a vinyl monomer mixture or the like, and then produced by a bulk polymerization method. 4) A method in which a rubber-like polymer obtained by a solution polymerization method is dissolved in a vinyl-based monomer to produce a bulk-suspension polymerization method. 5) A rubber-like polymer obtained by a solution polymerization method is There is known a method of dissolving in a system polymer or the like and producing it by a bulk polymerization method.

However, in the production method using the rubber-like polymer obtained by the solution polymerization method of 4) and 5), the particle size of the rubber-like polymer contained in the product is large, and the product of the method of 1) to 3) is large. Not enough gloss compared to Therefore, industrially 1)-
Method 3) is adopted.

That is, in general, an ABS resin or the like is obtained by graft-polymerizing a vinyl-based monomer onto a conjugated diene-based rubber-like polymer by emulsion graft polymerization. Manufacturing is required. Therefore, in order to recover the graft polymerization latex as a dried graft powder, complicated and various processes are required, and running costs, energy loss problems, reduction in product yield, and product costs centering on the drying process are reduced. There are many unfavorable points such as the high ratio of the occupation cost. In addition, the graft powder obtained here is a vinyl polymer powder obtained in the same manner, a polymer bead obtained by dehydrating and drying a vinyl polymer slurry obtained by suspension polymerization, or a vinyl bead obtained by bulk polymerization. Pellets such as ABS resin are formed by a method of mixing, extruding, and devolatilizing with a polymer-based pellet, or a method of mixing with a vinyl-based monomer or the like and performing bulk polymerization. However, in the former method, it is necessary to heat the vinyl polymer beads or pellets once solidified to a molten state, which is not preferable in terms of cost. In addition, the latter bulk polymerization method has a problem that the kind of ABS resin or the like which is a disadvantage of the bulk polymerization method is limited by the variety.

[Problems to be Solved by the Invention] Various proposals have conventionally been made to improve these points. For example, after coagulating a polymer latex,
A method of supplying the vinyl polymer pellets and / or beads together with the pellets and / or beads to a screw-type squeezing dehydrator to perform dehydration and drying, and to continuously remove the polymer in a molten state from a die at the end of the cylinder (Japanese Patent Application Laid-Open No. 56-18604). Publication). However, in this method, the steps of recovering and drying the graft polymer are simplified, but the vinyl polymer beads and / or pellets once solidified must be returned to a molten state as in the conventional method. Without
There is a disadvantage that energy loss is large.

Furthermore, as a method of improving these drawbacks, a continuous melt of a polymer latex is precipitated and coagulated, or a dehydrated polymer is supplied to a single device, and a liquid is discharged through a dewatering slit barrel, followed by heating and heating. The molten vinyl polymer obtained by the continuous bulk polymerization method or the melt polymerization method is injected into the molten state in a liquid state from a press-fitting barrel provided between the dewatering slit barrel and the first vent barrel. A method of producing an ABS resin by mixing, kneading, vaporizing residual moisture, residual monomers and the like from a vent barrel and removing the same outside the system (JP-A-62-158750) has been proposed.
However, in this method, the vent up in the first vent barrel is large, and the vent stuffer for suppressing this is large. In addition, the devolatilized monomer is mixed with a large amount of water, and in order to recycle and use it, an oil-water separator that selectively recovers only the monomer and solvent or an oil-resistant device that eliminates the flocculant is used. A reverse osmosis membrane module is required, which increases the cost of the product. Furthermore, after kneading the melted polymer latex and the melted vinyl polymer, the remaining moisture, remaining monomers, etc. are vaporized and removed from the first vent barrel, so that the weight of the two before kneading is reduced. The combined latex was dewatered, heated, and melted, resulting in insufficient removal of vaporized water and residual monomers.

The present invention has been made in view of such a situation, and has been found by various studies. The purpose of the present invention is to efficiently recover a polymer from a graft polymer latex and obtain the polymer by emulsion polymerization. Simplification and labor saving of the process of supplying the grafted polymer latex and the vinyl polymer in the molten state obtained by solution polymerization or / and bulk polymerization to a single device having a specific structure and collecting pellets such as ABS resin In

Further, a second object of the present invention is to provide a product resin having excellent impact resistance, a low residual volatile component in the resin, and yellowing, burning, and a thermoplastic resin such as an ABS resin having a high commercial value that does not contain contaminants. And a device therefor.

Further, as a third object of the present invention, a slurry obtained by emulsion polymerization from at least a first vent barrel of a single device, and residual moisture not discharged from a slit barrel of a hydropolymer are mainly evaporated, and at least A method and an apparatus for manufacturing a thermoplastic resin such as an ABS resin which aims to reduce the cost of products and reduce the burden of wastewater treatment by collecting volatile components discharged from the second vent barrel and recycling the collected volatile components. To provide.

[Means for Solving the Problems] That is, in the present invention, when a thermoplastic resin is produced from a graft polymer and a vinyl polymer, a) a conjugated diene rubber polymer is added to an aromatic vinyl polymer and an aromatic polymer. A latex obtained by emulsion graft polymerization of a monomer mixture of vinyl monomers other than vinyl, wherein a diene rubber-like polymer is contained in the total solid content of the latex.
Graft polymer latex containing ~ 80% by weight,
Slurry or hydrated polymer obtained from this latex b) Vinyl-based polymer latex, and of the slurry or hydrated polymer obtained from this latex, a) and b) or a) a graft polymer latex consisting solely, obtained from this latex The slurry or the hydrated polymer to be supplied is a feed barrel receiving at least the supply of these substances, a slit barrel for discharging these substances and discharging a liquid substance, a standard barrel having a heating means, and a discharge barrel for discharging vaporized substances. A vent barrel, a cylinder equipped with a split barrel of a press-fit barrel for press-fitting a polymer in a molten state, and at least a forward screw, a reverse screw and a split twin-screw of a kneading disc are combined, and vented. With at least two barrels After one vent barrel is supplied into a single device provided between the slit barrel and the press-fitting barrel connected to the feed barrel, dewatered / melted, and devolatilized by the vent barrel, A method for producing a thermoplastic resin, wherein a vinyl polymer in a molten state obtained by solution polymerization and / or bulk polymerization is continuously introduced into an apparatus by feeding the vinyl polymer into the press-fitting barrel.

The present invention also relates to an apparatus for producing a thermoplastic resin from a graft polymer and a vinyl polymer, the method comprising the steps of: a) adding a vinyl monomer other than an aromatic vinyl monomer and an aromatic vinyl to a conjugated diene rubber polymer; A latex obtained by emulsion graft polymerization of a monomer mixture of monomers, wherein a diene rubber-like polymer is contained in the total solid content of the latex.
Graft polymer latex containing ~ 80% by weight,
Slurry or hydrated polymer obtained from this latex b) Vinyl-based polymer latex, and of the slurry or hydrated polymer obtained from this latex, a) and b) or a) a graft polymer latex consisting solely, obtained from this latex Feed barrel receiving a slurry or hydrated polymer to be supplied, a slit barrel for discharging a liquid material, a standard barrel having a heating means, a vent barrel for discharging a vaporized material, and a press-fitting method for injecting a polymer in a molten state. It consists of a single device that combines at least a split barrel of a press-fitting barrel with each split twin screw of a forward screw, a reverse screw, and a kneading disk, and has at least two vent barrels. , At least one vent ballet Is provided between a slit barrel connected to the feed barrel and a press-fitting barrel for press-fitting a vinyl polymer in a molten state obtained by solution polymerization or / and bulk polymerization. This is an apparatus for producing a thermoplastic resin.

 Hereinafter, the present invention will be described in detail.

Examples of the graft polymer latex applied to the thermoplastic resin production method of the present invention include: a) polybutadiene, butadiene-styrene copolymer,
Conjugated diene polymers such as butadiene-acrylonitrile copolymer, ethylene-propylene-butadiene copolymer, butadiene-alkyl acrylate copolymer, isoprene rubber and chloroprene rubber, and styrene, α as aromatic vinyl monomers -Methylstyrene, at least one kind of p-methylstyrene, and vinyl monomers other than aromatic vinyl, such as vinyl cyanide monomers such as acrylonitrile and methacrylonitrile, ethyl acrylate, A polymer latex obtained by emulsion graft polymerization of a monomer mixture of at least one kind of alkyl (meth) acrylate such as 2-ethylhexyl acrylate, octyl acrylate, methyl methacrylate, and ethyl methacrylate. And this latex A graft polymer latex wherein the proportion of the diene rubber-like polymer in the solid content is 30 to 80% by weight; b) a monomer or monomer selected from the group of vinyl monomers shown in a) A vinyl polymer latex obtained by emulsion polymerization of a mixture, of which the graft polymer latex shown in a) and b)
And a mixed polymer latex obtained by mixing the vinyl polymer latex shown in (a) or the graft polymer latex shown in (a) alone. Also,
In the present invention, the above graft polymer latex,
A mixed polymer latex and a slurry or a hydrated polymer obtained from these latexes (hereinafter abbreviated as "emulsion graft polymer") can be used.

In b), the proportion of the diene rubber-like polymer in the total solid content of the polymer latex is usually 30 to 80% by weight,
Preferably, it is in the range of 40 to 65% by weight, and if it is less than 30% by weight, in order to sufficiently exhibit impact resistance of an ABS resin or the like, it is necessary to increase the use ratio of the emulsion polymer whose production cost is relatively high. On the other hand, if the content exceeds 80% by weight, the graft ratio of the graft product decreases, so that when it is used as a molded product, the impact resistance decreases and the surface gloss decreases.

The above-mentioned graft polymer latex used in the present invention, the emulsifier to be used for emulsion polymerization, an initiator,
Other chemicals such as a chain transfer agent are not limited at all, and any chemicals used in ordinary emulsion polymerization may be used.

Next, an apparatus for producing a thermoplastic resin from the emulsion graft polymer and the vinyl polymer of the present invention comprises a single apparatus,
A twin-screw extruder type having a cylinder, a screw having a split barrel, and a screw drive as main components is used. The apparatus of the present invention has a configuration having a main stream in which a barrel and a screw can be decomposed for each block, and a side stream to which a vinyl polymer in a molten state obtained by solution polymerization or / and bulk polymerization is supplied.

The barrel includes a feed barrel for receiving a supply of an emulsion graft polymer, a salting-out agent, a slit barrel having a slit for passing a liquid substance but not for passing a solid substance, a standard barrel having a heating means, and removing volatile components. Barrels each having a vent opening, a press-in barrel for press-fitting and adding a vinyl polymer and a lubricant, a pigment, a stabilizer and the like in a molten state obtained by solution polymerization or / and bulk polymerization, and There is a die for taking out the polymer composition in a molten state. These barrels can be freely combined and their positions and lengths can be changed according to the purpose. In particular, in the present invention, at least two or more vent barrels are provided, and at least one vent barrel is provided with a feed barrel. It is provided between the press-fitting barrel and the slit barrel connected to the barrel, and at least one other vent barrel is provided between the press-fitting barrel and the die.

Further, as the screw, a forward screw for feeding the polymer in the forward direction, a backward screw for feeding the polymer in the reverse direction, and a kneading disk for kneading the polymer are used, and these screws are biaxial split screws, and the barrel Similarly, the position and length can be changed according to the purpose. Therefore, in the apparatus of the present invention, the composition ratio of each barrel and the composition ratio of the screw of the single apparatus of the present invention are changed depending on the type of the polymer composition and the state of the slurry or the hydrated polymer charged into the apparatus. Thereby, the polymer composition can be taken out in an appropriate molten state. The heating means can be provided not only in the standard barrel but also in other barrels.

The essential factors of the device of the present invention are at least a feed barrel, a slit barrel, a standard barrel, a vent barrel, a cylinder having each split barrel composed of a press-fitting barrel, and at least a forward screw, a reverse screw,
A vented stuffer consisting of a kneading disk and a split twin screw and a die.In some cases, a popcorn-shaped polymer is sometimes returned from the vent port of the vent barrel. Ancillary equipment such as a gear pump may be connected and interposed.

Next, in the production method of the present invention, the emulsion graft polymer is fed into the above-described apparatus, dewatered, melted, and devolatilized, and then fed by using a press-in barrel, obtained by solution polymerization or / and bulk polymerization. As a vinyl polymer in a molten state to be obtained, aromatic vinyl monomers such as styrene, α-methylstyrene and p-methylstyrene include vinyl cyanide monomers such as acrylonitrile and methacrylonitrile;
Ethyl acrylate, 2-ethylhexyl acrylate,
Homopolymers and / or copolymers of alkyl (meth) acrylates such as octyl acrylate, methyl methacrylate, and ethyl methacrylate, acid anhydrides such as maleic anhydride, and imidized compounds thereof, and modified products thereof.

Hereinafter, the present invention will be described in more detail with reference to specific examples. However, the following examples are merely examples of the present invention, and do not limit the present invention in any way.

FIG. 1 is an explanatory view showing an example of the apparatus for producing a thermoplastic resin of the present invention. In FIG. 1, the graft polymer latex sent from a graft polymer latex storage tank 1 by a pump 2 is stirred and mixed in a mixing tank 5 with a flocculant sent from a flocculant storage tank 3 by a pump 4. As a result, the emulsion is destroyed by emulsification, and a slurry in which the polymer is aggregated is obtained. This slurry is sent to a filter 7 by a pump 6 and is subjected to a water flow of an emulsifier, an emulsion stabilizer, and a polymer flocculant, which have an unfavorable effect on the mechanical strength of the recovered polymer and the appearance after molding. , Supplied to a single device of the invention.

In FIG. 1, (A), (B) and (C) show cross sections of the barrel configuration, screw configuration and screw configuration, respectively, which are basic components of the single device. _{F, H, S, V 1} , V 2, P, D , each show the feed barrel, standard barrel, slit barrel vent barrels (V _1, V _2), a press-fitting the barrel and the die, X, Y, Z is , A forward screw, a kneading disc and a reverse screw, respectively. In particular, in the single apparatus, the vent barrels are used two, first vent barrel V ₁ was arranged in connection with the standard barrel H between the slit barrel S and press-fitting the barrel P,
The second vent barrel V ₂ is arranged in connection with one of the standard barrel H between the press-fitting the barrel P and the standard barrel H.

In the above single apparatus, the partially dehydrated graft polymer slurry coming out of the filter 7 is supplied to the feed barrel F, and the feed barrel F and the forward screw X
Is sent forward by The graft polymer slurry sent to the slit barrel S is further back-pressured by a kneading disk Y and a reverse screw Z provided on the front screw, and the water, emulsifier, emulsion stabilizer, polymer flocculant, etc. Is discharged out of the system through the slit. Dehydrated graft polymer is heated and melted in a standard barrel H, graft polymers residual water and residual monomer is contained in the like are removed from the system as a gas at a first vent barrel V _1. In this case, it is further effective should also provided with a heating means to a first vent barrel V _1.

On the other hand, the vinyl polymer in the molten state supplied from the press-in barrel P is produced as follows. That is,
The monomer mixture is continuously supplied from a raw material tank 8 to a reactor 10 by a pump 9, polymerized here, and then continuously discharged out of the reactor 10 by a withdrawal pump 11.
After the discharged vinyl polymer is heated by the preheater 12, the unreacted monomer and the solvent are removed in the flash tank 13, and the main stream heating means is melted by the extraction pump at the lower part of the flash tank 13. Is supplied to the press-fitting barrel P provided with. The mixture of the molten vinyl polymer supplied to the press-fitting barrel P and the heated and melted graft polymer present in the main stream is heated and mixed by the forward screw in the press-fitting barrel P and sent forward. Can be Furthermore, mixed polymer mixture by kneading disks Y direction opposite screw Z finally the second system as residual water and residual monomers are gases are contained in the polymer mixture at a vent barrel V ₂ After being removed from the inside and devolatilized in this manner, it is recovered from the die D. At this time, in the case of a resin having poor thermal stability, such as an ABS resin, a gear pump 17 can be provided before the die as shown in FIG. 1 to prevent the resin from staying.

The molten resin discharged from the die D is collected by a known method such as hot cut, underwater cut, and strand cut.

The residual water and residual monomers removed from the vent barrels V ₁ and V ₂ as gases from the system can be appropriately separated and recovered, and recycled. For example,
In order to recover the residual monomer, it is recovered by using a generally used recovery device for volatile components, and is recycled as a raw material for synthesizing a graft copolymer latex or a vinyl polymer, thereby reducing product cost. The burden on wastewater treatment can be reduced.

According to the single-screw single device of the present invention described above, after dehydration, heating and devolatilization of the emulsion graft polymer obtained by the emulsion polymerization method, a solution polymerization or By continuously feeding the vinyl polymer in the molten state obtained by bulk polymerization from the press-in barrel, ABS resin and the like can be manufactured, which simplifies the process and saves labor compared to conventional methods. Achieved.

In particular, in the single device of the present invention, at least two vent barrels are provided, and at least one first vent barrel is provided between the slit barrel connected to the feed barrel and the press-fit barrel. Therefore, residual moisture and residual monomers contained in the emulsion graft polymer can be removed from the system as a gas, and then the molten vinyl polymer is injected into the second vent barrel by a press-fitting barrel. The residual water and residual monomers contained in the mixed polymer fed by using are finally removed from the system as a gas, so that the residual volatile components in the product resin can be extremely reduced.

Furthermore, according to the method of the present invention, a resin component having a different melting temperature, ABS having better heat resistance than a normal ABS resin or the like.
An example of a process for producing a resin will be described based on an apparatus shown in FIG.

FIG. 2 is an explanatory view showing another example of the apparatus for producing a thermoplastic resin of the present invention. In FIG. 2, 1 to 13 correspond to the first
It is a device similar to the device in the figure. An emulsion graft polymer obtained by an emulsion polymerization method and a vinyl polymer obtained by a continuous solution polymerization method are mixed and heated in the same procedure as in the example of FIG.

On the other hand, a resin solution stored in the hold tank 14 and having a higher heat resistance than a normal ABS resin or the like, for example, a polymer solution such as a styrene-maleic anhydride copolymer or a styrene-N-substituted maleimide copolymer is extracted. 4-stage vented twin-screw extruder including one rear vent port by pump 15
Supply 16 Here, the heated and devolatilized polymer having excellent heat resistance is press-fitted into a single device of the present invention by a gear pump provided at the tip of a twin-screw extruder 16 and provided with a press-fitting barrel provided with heating means. It is supplied from the P _2.

A polymer mixture consisting of an emulsion graft polymer, a vinyl copolymer, and a polymer having excellent heat resistance is injected into this press-fitting barrel.
The forward screw in the P ₂ are mixed under heating, and sent forward. Furthermore, mixed polymer mixture by kneading disks Y direction opposite screw Z finally the second system as residual water and residual monomers are gases are contained in the polymer mixture at a vent barrel V ₂ After being removed from the inside and devolatilized, it is pumped to the die D by the gear pump 17 and collected from the die D.

According to the conventional method, even in the production of an ABS resin or the like made of a polymer mixture having significantly deteriorated heat resistance, since the inlet of each polymer as a raw material is common, from the barrel immediately after the inlet, A temperature setting at which a polymer having high heat resistance is melted is required. Therefore, in this case, the rubbery polymer having low heat resistance is also exposed to a high temperature, and a cross-linking reaction occurs, and ABS
Not only does the impact resistance, which can be said to be a characteristic of resins, decrease,
Burning of the resin occurs, resulting in yellowing and contamination of the resin, which significantly reduces the commercial value of the resin.

According to the single-screw single-screw device used in the present invention described above, the length of the barrel and the screw are partially extended, and the appropriate barrel, screw configuration and polymer are adjusted according to the physical properties of the feed. By setting the order of introduction, it is possible to avoid a drop in impact resistance and to provide A with better heat resistance than ordinary ABS resin etc.
A polymer such as a BS resin can be obtained.

These physical advantages are further clarified in the following examples together with the rationality of the present invention.

[Example] Hereinafter, the present invention will be described more specifically with reference to examples. In addition, the number of parts in the examples indicates the number of parts by weight,
The physical strength was measured based on JIS standards.

○ Measurement method Izod impact strength: JIS K-7110 Tensile yield strength: JIS K-7113 Elongation: JIS K-7113 Vicat softening point: JIS K-7206 Residual monomer: Residual monomer in the polymer is o- It was measured by gas chromatography by an internal standard method using xylene as a standard solution.

Example 1 An ABS resin was produced by the method shown in FIG.

a) A graft polymer latex was produced according to the following polymerization recipe.

Charged materials were charged parts polybutadiene latex (solid content) 100 parts Styrene 75 parts Acrylonitrile 25 parts t- dodecyl mercaptan 1 parts FeSO ₄ · 7H ₂ O 0.02 parts EDTA · 4Na salt 0.05 part of sodium formaldehyde sulfoxylate · The Shireto 0.2 parts t- Buchirupa Acetate 0.2 parts Cumene hydroxy peroxide 0.1 parts Sodium laurate 2.0 parts H ₂ O (including water in polybutadiene latex) 263 parts Polymerization time 6 hours Polymerization temperature 50 ° C → 70 ° C Monomer, t-butyl peracetate and emulsifier Was added continuously for 4 hours at a constant speed, the polymerization temperature was raised to 70 ° C., and cumene hydroxy peroxide was added continuously at a constant speed for 1 hour. Further, the polymerization reaction was continued for 1 hour at 70 ° C. to obtain a graft polymer latex. After the completion of the polymerization reaction, the hindered phenol-based antioxidant and the phosphorus-based stabilizer were emulsified and mixed.

b) A vinyl polymer in a molten state was obtained by the following polymerization recipe.

Charged materials Charged parts Styrene 60 parts Acrylonitrile 20 parts Ethylbenzene 20 parts The monomer mixture was fed from a raw material tank 8 in which the above-mentioned monomer mixture was adjusted to a reactor 10 whose internal temperature was maintained at 155 ° C by a pump 9. The discharge speed of the extraction pump 11 was set so that the average residence time in the reactor was about 4 hours. The resin component concentration in the polymer solution measured at the outlet of the pump 11 was about 60% by weight, and the acrylonitrile unit in the resin component was 25.5% by weight.

The polymer solution was heated to 200 ° C. by the preheater 12, and the unreacted monomers were removed in the flash tank 13 at a reduced pressure of 50 Torr to obtain a polymer in a molten state.

The graft polymer latex prepared in a) was sent from the tank 1 and a 3% by weight aqueous magnesium sulfate solution was sent from the tank 3 to the mixing tank 5 at a ratio of approximately 10: 9 using pumps 2 and 4, respectively, and stirred and mixed. Then, a slurry having a polymer concentration of 20% was obtained. This was sent to a filter 7 by a pump 6 and dewatered, washed with water, and dehydrated to a polymer concentration of 70%.

The barrel (bore diameter 50 mm) and the screw configuration of the single screw-type single screw device are shown in FIGS. 1A and 1B, respectively. The temperature of each barrel is 170 ° C (H) and 200 ° C, respectively, from the standard barrel H following the slit barrel toward the tip.
(V ₁ ), 200 ℃ (P), 180 ℃ (H), 180 ℃ (V ₂ ), 180 ℃
(H), 180 ° C (H), and the temperature of the die D part is 250 ° C
And The rotation number of the screw was 300 rpm.

Next, a wet cake having a polymer concentration of 70% by weight was transferred from the filter 7 to the feed barrel F at a rate of 52 kg / hr. Start rotation of the screw at the start of transfer,
The vacuum pump directly connected to the vent was operated. afterwards,
The vinyl polymer in a molten state was supplied to the press-fitting barrel P at a rate of 64 kg / hr by a gear pump installed below the flash tank 13. A few minutes after the supply of the vinyl polymer in the molten state was started, the state became a steady state, and the ABS resin in the molten state was discharged from the die part D, so after cooling this polymer in a cooling tank, cut with a pelletizer, Exhaust from the pellets and vent barrels V ₁ and V ₂ was continuously collected.

The composition of the obtained ABS resin pellets, water discharged from the slits of the slit barrel S, and the exhaust from the vent barrels V ₁ and V ₂ were as follows.

(1) ABS resin pellets (rubber content 18% by weight) Discharge rate: 100kg / hr Hue: good Recovery rate: 99.6% (in terms of polymer) Physical property: Izod impact strength 25kg · cm / cm tensile yield Strength 4.6 kg / mm ² Elongation 20% Vicat softening point 99 ° C Residual monomer: Styrene 700 ppm Ethyl benzene 400 ppm Acrylonitrile 40 ppm (2) Total water discharged from slits 15.2 kg / hr Water-insoluble matter (mainly polymer) 0.4 kg / hr (3) emissions from the vent barrels (3-1) exhaust water 0.9 kg / hr monomers fine amount from the vent barrel V ₁ (3-2) exhaust water from the vent barrel V ₂ 0.1 kg / hr monomers 0.3 kg / hr (4) required power amount per dynamic force ABS resin pellets 1t 280Kw Incidentally, did not have a any effect the collected material to the polymerization system be added during the emulsion polymerization of the vent barrel V ₂ Was.

From the above experimental results, the production method of the present invention efficiently supplies the AS resin in a molten state obtained by continuous solution polymerization with a graft polymer slurry having high industrial value to a single twin-screw device. By doing so, it is clear that an ABS resin with a low impurity content can be produced.

Comparative Example 1 c) A vinyl polymer slurry was produced according to the following polymerization recipe.

Mixing composition charged Copies H ₂ O 55 parts calcium tertiary phosphate 0.5 parts of styrene 52 parts After the heating of acrylonitrile 26 parts of t- butyl peroxy acetate 0.08 parts of t- dodecylmercaptan 0.35 parts of potassium persulfate 0.02 parts The above composition to 103 ° C., The following composition was added at a constant speed over a period of 6 hours to proceed the polymerization reaction. The temperature was further raised to 120 ° C., kept at this temperature for 2 hours, and then cooled.

Addition composition Addition number Addition of H ₂ O 50 parts Styrene 22 parts After neutralizing and dewatering this AS bead slurry, Example 1
A graft polymer latex similar to that described above and the AS bead slurry dehydrated were weighed so that the weight ratio of the solid content in the graft polymer latex to the AS beads was 36:64, and then transferred to the latex mixed layer 5. . This is sent to a filter 7 by a pump 6 and washed with water after dehydration.
Dehydrated to 70%.

The barrel (bore diameter 50 mm) and the screw configuration of the single screw-type single screw device are shown in FIGS. 1A and 1B, respectively. The temperature of each barrel is 170 ° C. (H) and 200 ° C., respectively, from the standard barrel H next to the slit barrel S toward the tip.
℃ (V ₁ ), 200 ℃ (P), 180 ℃ (H), 180 ℃ (V ₂ ), 180 ℃
(H), 180 ° C (H), and the temperature of the die D part is 250 ° C
And The rotation number of the screw was 300 rpm.

Next, a wet cake having a polymer concentration of 70% was transferred from the filter 7 to the feed barrel F at a speed of 143 kg / hr. The rotation of the screw was started when the transfer was started, and the vacuum pump directly connected to the vent port was operated. After a few minutes from the start of the supply of the polymer mixture, the state became a steady state, and the ABS resin in a molten state was discharged from the die part D, so after cooling this polymer in a cooling tank, cut it with a petizer, and pelletized. Collected continuously.

The composition of the obtained ABS resin pellet, water discharged from the slit of the slit barrel S, and exhaust from the vent barrel were as follows.

(1) ABS resin pellets (rubber content 18% by weight) Discharge rate: 100 kg / hr Hue: yellowish Recovery rate: 99.% (polymer equivalent) Physical property: Izod impact strength 24 kg・ Cm / cm Tensile yield strength 4.4kg / mm ² elongation 20% Vicat softening point 98 ° C Residual monomer: styrene 1500ppm acrylonitrile 60ppm (2) Total water discharged from slits 41.2kg / hr Water-insoluble matter (mainly polymer) 1.0kg / hr (3) vent barrel (V ₁ + V emissions total recovery from ₂₎ 2.0 kg / hr monomers 0.2kg / hr (4) required power amount per dynamic force ABS resin pellets 1t 350 kW Comparing the ABS resins obtained in Example 1 and Comparative Example 1, the case of the method of the present invention is superior in that the hue and the residual monomer content are small, and the method of the present invention is more process-friendly. Has also been simplified. Also requires less power.

Example 2 A heat-resistant ABS resin was produced by the method shown in FIG.

d) A maleimide polymer was produced according to the following polymerization recipe based on the examples described in JP-B-61-26936.

Charged Materials Charged Number of Styrene 75 parts This styrene was charged into the hold tank 14, heated to 80 ° C., and the following composition was added at a constant speed for 10 hours.

 Additives Addition number of parts Methyl ethyl ketone 50 parts Maleic anhydride 25 parts Benzoyl peroxide 0.3 parts After completion of the addition, the mixture was kept at 80 ° C for 2 hours.

The following additives were added to the copolymer composition, and 13
After the temperature was raised to 0 ° C., the reaction was carried out for 7 hours.

Additives Addition number of parts Methyl ethyl ketone 180 parts Triethylamine 1 part Aniline 26.9 parts A twin-screw extruder 16 with a four-stage vent including one stage of rear vent 16
Then, the solvent was devolatilized and the temperature of the resin was raised, and finally a polymer in a molten state heated to 300 ° C. was obtained.

The graft polymer latex prepared in a) was sent from the tank 1 and a 3% by weight aqueous magnesium sulfate solution was sent from the tank 3 to the mixing tank 5 at a ratio of approximately 10: 9 using pumps 2 and 4, respectively, and stirred and mixed. Then, a slurry having a polymer concentration of 20% was obtained. This was sent to a filter 7 by a pump 6 and dewatered, washed with water, and dehydrated to a polymer concentration of 70%.

The barrel (diameter: 50 mm) and screw configuration of a single screw-type single screw device are shown in FIGS. 2A and 2B, respectively. The temperature of each barrel is 220 ° C (H) and 250 ° C, respectively, from the standard barrel H following the slit barrel toward the tip.
(V ₁ ), 280 ° C (P ₁ ), 280 ° C (H), 260 ° C (P ₂ ), 260 ° C
(H), 260 ° C. (V ₂ ), 260 ° C. (H), 260 ° C. (H), and the temperature of the die D was 280 ° C. The rotation number of the screw was 300 rpm.

Next, a wet cake having a polymer concentration of 70% was transferred from the filter 7 to the feed barrel F at a speed of 52 kg / hr. The rotation of the screw was started when the transfer was started, and the vacuum pump directly connected to the vent port was operated. After that, the melted vinyl polymer having a composition in which the acrylonitrile unit in the AS polymer component was 28.0% by weight was pumped into the barrel P at a speed of 25 kg / hr by a gear pump installed at the lower part of the flash tank 13 at a speed of 25 kg / hr. It was fed to the _1. Then, the maleimide polymer in the molten state from a gear pump with a twin-screw extruder 16 at a rate of 39 kg / hr, was fed to the next press fitting the barrel P _2. After several minutes, the state became a steady state, and the ABS resin in a molten state was discharged from the die part D. The polymer was cooled in a cooling tank, cut with a pelletizer, and pellets were continuously collected.

The compositions of the obtained heat-resistant ABS resin pellets, water discharged from the slits of the slit barrel S, and exhaust from the vent barrels V ₁ and V ₂ were as follows.

(1) ABS resin pellets (rubber content 18% by weight) Discharge rate: 100 kg / hr Hue: good Recovery rate: 99.6% (polymer equivalent) Physical property: Izod impact strength 17 kg · cm / cm tensile yield strength 4.2 kg / mm ² elongation 30% Vicat softening point 128 ° C. residual monomers: styrene 700ppm ethylbenzene 200ppm acrylonitrile <30 ppm methyl ethyl ketone 50ppm aniline 40 ppm (2) water total emissions 15.2 kg / hr water insolubles discharged from the slit ( mainly polymer) 0.4 kg / hr (3) emissions from the vent barrels (3-1) exhaust water 0.9 kg / hr monomers fine amount from the vent barrel V ₁ (3-2) from the vent barrel V ₂ Exhaust water 0.1 kg / hr Monomer, etc. 0.4 kg / hr (4) Power Required power per ton of ABS resin pellets 320 kw Comparative Example 2 Coagulation and dehydration of the graft polymer latex used in Example 1 by a conventional method・ Dry The obtained graft polymer powder, AS dry beads obtained by neutralizing, dehydrating and drying the AS slurry obtained by the suspension polymerization method used in Comparative Example 1 by a conventional method, and the twin screw of Example 2 Using a die obtained by placing a die at the exit of the extruder and cutting the strand-like maleimide-based copolymer,
The pellets of the heat-resistant ABS resin obtained in Example 2 were blended and pelletized by a conventional method, and the physical properties thereof were compared.

That is, the solid content of the graft polymer latex of a) is 100
2 parts of magnesium sulfate was added to each part to coagulate the polymer, and the obtained slurry was washed and cut off with a centrifugal separator, and dried at 60 ° C. for 24 hours with a shelf-type hot air dryer to remove the graft polymer powder. Obtained.

Further, the AS slurry of b) was neutralized by adding hydrochloric acid, washed and dehydrated with a centrifugal separator, and dried at 80 ° C. for 5 hours with a shelf dryer to obtain AS dry beads.

These polymers and the maleimide-based copolymer pellets of d) were blended in a weight ratio of graft polymer powder: AS dry beads: maleimide-based polymer pellets of 36:25:39, and this was blended. It was pelletized by an extruder with a 40 mmφ vent. The physical properties of the pellet are shown below.

Physical properties: Izod impact strength 15 kg · cm / cm Tensile yield strength 4.2 kg / mm ² elongation 26% Vicat softening point 125 ° C Residual monomer: styrene 1500 ppm acrylonitrile 70 ppm methyl ethyl ketone 500 ppm aniline 90 ppm Example 2 and Comparative Example 2 Comparing the physical properties of the ABS resin obtained in the above, the method according to the method of the present invention is superior. It is also clear that the present invention is significantly simplified in the process.

Comparative Example 3 In the apparatus shown in FIG. 1 used in Example 1, a press-fitting barrel P for press-fitting a vinyl polymer in a molten state and a vent barrel
Interchanged V _1, also to prepare a ABS resin using the apparatus shown in Figure 3 has been changed screw configuration.

That is, as shown in FIG. 3, the vent barrels V ₃ and V ₄
The provided a first vent barrel V ₃ is provided immediately after the press-fitting the barrel P, the said vent barrel V ₃ set up a vent stuffer, to prepare a ABS resin in the same manner as in Example 1.

The composition of the obtained ABS resin pellets, the water discharged from the slits of the slit barrel S, and the discharges from the vent barrels V ₃ and V ₄ were as follows.

(1) ABS resin pellets (rubber content 18% by weight) Discharge rate: 99.4kg / hr Hue: good Recovery rate: 99.0% (in terms of polymer) Physical properties: Izod impact strength 25kg · cm / cm tensile yield strength 4.5 kg / mm ² elongation 18% Vicat softening point 99 ° C. residual monomers: styrene 1000ppm ethylbenzene 580ppm acrylonitrile 60 ppm (2) water total emissions discharged from the slit 15.1 kg / hr water insolubles (primarily polymer) 0.4 kg / hr (3) emissions from the vent barrels (3-1) popcorn-like polymer 0.6 kg / hr (3 jumping out of exhaust water 0.7 kg / hr monomers fine amount vent barrel V ₃ from the vent barrel V ₃ -2) When emissions from exhaust water 0.3 kg / hr monomers 0.3 kg / hr vent barrel V ₄ from the vent barrel V ₄ is added during the emulsion polymerization, the polymer deposition is heavily caused in the wall of the polymerization vessel.

[Effects of the Invention] As is clear from the above results, according to the present invention, a polymer can be efficiently recovered from a graft polymer latex, and the graft polymer latex obtained by emulsion polymerization and solution polymerization or And / or the process of supplying a vinyl polymer in a molten state obtained by bulk polymerization to a single device and collecting pellets such as ABS resin can be simplified and labor can be saved.

Further, the present invention can provide an ABS resin and the like having high commercial value, which has excellent impact resistance, has low residual volatile components in the resin, and does not contain yellowing, burns, contamination, and the like.

Further, according to the present invention, the slurry obtained by emulsion polymerization from at least the first vent barrel and the residual water not discharged from the slit barrel of the hydrous polymer are mainly evaporated and discharged from at least the second vent barrel. By collecting and recycling volatile components, it is possible to reduce the cost of products and the burden on wastewater treatment.

[Brief description of the drawings]

1 and 2 are explanatory views showing one embodiment of the apparatus for producing a thermoplastic resin of the present invention, and FIG. 3 is an explanatory view showing an apparatus for producing a thermoplastic resin of Comparative Example 3. A ...... barrel configuration, B ...... sectional F ...... feed barrel screw configuration C ...... screw configuration, S ...... slit barrel _{V 1, V 2, V 3} , V 4 ...... vent barrels H ...... Standard barrel P, P ₁ , P ₂ … Press-fitting barrel D… Die X… Forward screw Y… Kneading disc Z… Reverse screw 1… Graft polymer latex storage tank 2, 4, 6, 9, 11, 15 Pump 3 Coagulant storage tank 5 Mixing tank 7 Filter 8 Raw material tank 10 Reactor 12 Preheater 13 Flash tank 14 Hold tank 16… Twin screw type extruder 17… Gear pump

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) C08L 55 / 02,51 / 04 C08F 279/02 C08J 3/20

Claims (2)

(57) [Claims] (1) In producing a thermoplastic resin from a graft polymer and a vinyl polymer, a) a conjugated diene-based rubber polymer is added to an aromatic vinyl-based polymer and a vinyl-based monomer other than aromatic vinyl; Latex obtained by emulsion graft polymerization of the monomer mixture, wherein the total solid content of the latex contains 30% of a diene rubber-like polymer.
Graft polymer latex containing ~ 80% by weight,
Slurry or hydrated polymer obtained from this latex b) Vinyl-based polymer latex, and of the slurry or hydrated polymer obtained from this latex, a) and b) or a) a graft polymer latex consisting solely, obtained from this latex The slurry or the hydrated polymer to be supplied is a feed barrel receiving at least the supply of these substances, a slit barrel for discharging these substances and discharging a liquid substance, a standard barrel having a heating means, and a discharge barrel for discharging vaporized substances. A vent barrel, a cylinder equipped with a split barrel of a press-fit barrel for press-fitting a polymer in a molten state, and at least a forward screw, a reverse screw and a split twin-screw of a kneading disc are combined, and vented. With at least two barrels After one vent barrel is supplied to a single device provided between the slit barrel and the press-fitting barrel connected to the feed barrel, dewatered and melted, and devolatilized by the vent barrel, A method for producing a thermoplastic resin, wherein a vinyl polymer in a molten state obtained by solution polymerization and / or bulk polymerization is continuously introduced into an apparatus by feeding the vinyl polymer into the press-fitting barrel. 2. An apparatus for producing a thermoplastic resin from a graft polymer and a vinyl polymer, the method comprising: (a) adding a vinyl monomer other than an aromatic vinyl monomer and an aromatic vinyl to a conjugated diene rubber polymer; Latex obtained by emulsion graft polymerization of a monomer mixture of a monomer, a diene rubber-like polymer in the total solid content of this latex is 30.
Graft polymer latex containing ~ 80% by weight,
Slurry or hydrated polymer obtained from this latex b) Vinyl-based polymer latex, and of the slurry or hydrated polymer obtained from this latex, a) and b) or a) a graft polymer latex consisting solely, obtained from this latex Feed barrel receiving a slurry or hydrated polymer to be supplied, a slit barrel for discharging a liquid material, a standard barrel having a heating means, a vent barrel for discharging a vaporized material, and a press-fitting method for injecting a polymer in a molten state. It consists of a single device that combines at least a split barrel of a press-fitting barrel with each split twin screw of a forward screw, a reverse screw, and a kneading disk, and has at least two vent barrels. , At least one vent ballet Is provided between a slit barrel connected to the feed barrel and a press-fitting barrel for press-fitting a vinyl polymer in a molten state obtained by solution polymerization or / and bulk polymerization. Thermoplastic resin manufacturing equipment.