JP2010046894A - Method of recycling plastic waste as reclaimed material, method of manufacturing plastic molded form and plastic molded form - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of efficiently recycling plastic waste as a reclaimed material which can obtain a plastic molded form with properties conforming to various uses through material recycling even if the material to be recycled is an alloy resin (PC+ABS) of a non-compatible polycarbonate resin and an acrylonitrile-butadiene-styrene resin, and also can reduce the plastic waste to be thermally recycled. <P>SOLUTION: This method is to recycle the plastic waste of an alloy resin of a polycarbonate resin and an acrylonitrile-butadiene-styrene resin as a reclaimed material, and includes a process to mix the alloy resin and the acrylonitrile-butadiene-styrene resin. Also, the method of manufacturing a plastic molded form including the method of recycling the plastic waste as a reclaimed material and the plastic molded form obtained by the method of manufacturing the plastic molded form are provided. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a method for recycling plastic waste. The present invention also relates to a method for producing a plastic molded body and a plastic molded body.

  In recent years, with the improvement of income levels in Japan, air conditioners (hereinafter also referred to as “air conditioners”) and television receivers (hereinafter referred to as “TV” in this specification). .), Home appliances such as refrigerators and washing machines, personal computers, information devices such as word processors, office equipment such as printers and fax machines, and various other furniture, stationery, toys, etc. Convenience in home life has been dramatically improved. As a result, the amount of discarded products such as these home appliances tends to increase year by year. Conventionally, the recycling of waste materials such as home appliances has often been performed through the iron scrap collection route.

  However, in recent years, the constituent materials of members of various products including home appliances have changed, the number of members made of metal such as iron has decreased, and the proportion of members made of plastic tends to increase. Plastics have a greater degree of design freedom than metals such as iron, and exhibit various properties that are difficult to achieve with metals by preparing components and using additives, and are lightweight and highly durable. This is because it has many advantages.

  Waste materials of various products such as home appliances in recent years have a complicated material composition of various components, the ratio of members made of valuable metals such as iron and copper is reduced, and the value is low. In the conventional processing method, the proportion of plastic members (hereinafter also referred to as “plastic members”), which requires a lot of labor and cost, is increasing. Moreover, the conventional iron scrap recovery route is becoming difficult to deal with because it cannot be profitable even if such waste material is recycled.

  Many of these plastic members are synthesized using a buried fossil fuel such as crude oil as a basic raw material, and from the viewpoint of effective utilization of resources, promotion of recycling of these plastic members has been strongly demanded in recent years.

  In addition, carbon dioxide and sulfur oxides released from combustion of crude oil and other buried fossil fuels cause global warming, environmental destruction such as acid rain, dioxins produced by incineration of plastics containing chlorine compounds, and environmental pollution such as scattering. Problems such as a shortage of landfill disposal sites due to an increase in waste materials containing bulky plastics have occurred. From the viewpoint of suppressing these problems, recycling of waste materials made of plastics should be resolved urgently and urgently. It is becoming an issue.

  In response to the above situation, the Home Appliance Recycling Law was enforced in April 2001. Under the Home Appliance Recycling Law, it is obliged to recycle four items of home appliances such as air conditioners, TVs, refrigerators and washing machines. A legal reference value of 50% or more of the washing machine is set.

  In response to the enforcement of the Home Appliance Recycling Law, collection of plastic member waste (hereinafter also referred to as “plastic waste”) is progressing. As a method for recycling the collected plastic waste, a so-called thermal recycling method using plastic waste as a fuel has been widely used. However, according to such a method, there is a problem such as generation of carbon dioxide gas due to combustion, so it cannot be said that the method is sufficiently in line with social demands.

  Therefore, for example, by manually dismantling the collected plastic waste material, separating the plastic members for each plastic system, and processing the plastic members again into product members or their raw materials for plastic waste materials to be used A recycling method has been proposed. Such a recycling method is called “material recycling” in contrast to the thermal recycling described above.

  Among the plastic members separated for each plastic system as described above, a plastic member can be relatively easily material-recycled by heating and melting and re-molding. For this reason, research and development of a method for recycling plastic waste materials by material recycling has been conducted with great efforts in various fields with the aim of increasing the material recycling ratio of plastic waste materials.

  However, plastic waste, especially plastic waste used in household appliances and office equipment, is often used for a long time in a harsh environment, so its characteristics have already deteriorated when it is used. In addition to deterioration in appearance characteristics such as discoloration or fading, physical properties such as strength and flexibility are often lowered, resulting in poor durability. For this reason, plastic waste is not a substitute for plastic virgin materials used for plastic members having high required characteristics, and is often used as a raw material for plastic members having low required characteristics. Here, in this specification, the “virgin material” means an unused resin composition. In addition, in this specification, the use of plastic waste material with reduced properties as a raw material for plastic members with low required properties, rather than as a substitute for virgin materials used for plastic members with high required properties, is referred to as “cascade recycling”. Shall be described.

  At present, this kind of cascade recycling is the mainstream for material recycling of plastic waste. Therefore, the use of the plastic molded body recycled from the plastic waste material is limited, and there is a problem that a large amount of plastic waste material is thermally recycled.

  In order to overcome these problems, much research and development has been carried out to improve the properties of plastic moldings obtained by material recycling from plastic waste, and to achieve a level that can be used as plastic components with high required properties. ing. For example, many methods for maintaining characteristics by mixing a virgin material with plastic waste material (material recycling material) have been proposed (for example, Japanese Patent Laid-Open No. 2000-159900 (Patent Document 1) and Japanese Patent Laid-Open No. 2001-26719). No. (Patent Document 2), Japanese Patent Application Laid-Open No. 2003-160724 (Patent Document 3), etc.). However, in the material recycling methods as disclosed in Patent Documents 1 to 3, it is often necessary to mix a larger amount of virgin material than plastic waste, and it is difficult to say that it corresponds to a resource recycling society. .

  In addition, a material recycling method of an aromatic polycarbonate resin and an ABS resin alloy resin has been proposed (see, for example, JP-A-2007-238817 (Patent Document 4)). However, in the material recycling method disclosed in Patent Document 4, since only an additive such as a rubber component is mixed, deterioration of the aromatic polycarbonate resin and ABS resin alloy which are base materials If the degree is large, there is a problem that it is difficult to recover to the same characteristics as the virgin material.

Furthermore, a chemical recycling method in which plastic waste (waste aromatic polycarbonate resin) is monomerized by transesterification to regenerate the raw material has been proposed (see, for example, Japanese Patent Application Laid-Open No. 2003-171324 (Patent Document 5)). .) However, in this method, there are problems that the equipment necessary for the monomerization is large and requires a lot of cost, and that it is difficult to apply to an alloy material of polycarbonate and other thermoplastic resins.
JP 2000-159900 A JP 2001-26719 A JP 2003-160724 A JP 2007-238817 A JP 2003-171324 A

  As mentioned above, it is a recycling method by material recycling that uses plastic waste recovered from the market as the main raw material, and it has a wide range of uses for the plastic molded body, and has characteristics that can be used as a plastic member or its raw material. There is a demand for a method for obtaining a molded article having the same. In addition, development of an efficient and low-cost method for recycling plastic waste is strongly desired. However, such a recycling method is not yet known.

  Recently, flat panel displays (FPD: Flat Panel Display) such as liquid crystal display, plasma display, organic EL (Electro Luminescence) display, inorganic EL display, field emission display (FED), and electronic paper For example, it has been widely used in various fields such as a television, a personal computer, a monitor, a video, a camera, a mobile phone, a car navigation, an information portable terminal, and a small game machine. The market size of FPD is increasing rapidly with the progress of the advanced information society in recent years due to its power saving, space saving and light weight. Along with this, the amount of disposal of these FPDs is expected to increase year by year, and in environmental activities such as recycling activities, there is an increasing demand for improving recyclability.

  However, these FPDs are relatively new products, and at present the amount of waste is relatively small, and recycling such as CRT televisions has not been put into practical use. The current situation is that the discarded FPD is crushed in a waste treatment facility and is landfilled or incinerated with shredder dust.

  In addition, flat TVs such as liquid crystal displays and plasma displays are being added as items to be applied under the Home Appliance Recycling Law in the near future. In this case, from the viewpoint of effective use of resources and improvement of the recycling rate, development of a recycling method for plastic waste materials used in the cabinet of the product is strongly desired.

  For example, in a cabinet of a liquid crystal television which is an example of a thin television, an alloy resin (PC + ABS resin) made of a polycarbonate resin and acrylonitrile-butadiene-styrene resin is often used. The alloy resin is one of materials having excellent heat resistance, self-extinguishing properties, moldability, and excellent mechanical properties. On the other hand, since the polycarbonate resin and acrylonitrile-butadiene-styrene resin are basically incompatible, for example, the acrylonitrile-butadiene-styrene resin dispersed in the polycarbonate resin is agglomerated by heat energy at the time of injection molding. May cause deterioration of mechanical properties. When recycling is considered, at least two injection moldings (formation of virgin material and molding of waste material) cause acrylonitrile-butadiene-styrene resin to agglomerate and cause deterioration of mechanical properties, which causes polycarbonate resin and acrylonitrile. -It is also one factor which inhibits the recyclability of the alloy resin (PC + ABS resin) which consists of butadiene-styrene resin. This phenomenon is the same in the alloy material (PC + PS) of polycarbonate resin and polystyrene resin.

  In addition, polycarbonate resin has a carbonate structure and is prone to hydrolysis due to its chemical structure. Especially, in combination with phosphate ester flame retardant, its properties are remarkable, so it has the same characteristics as virgin material. It is a difficult material to improve.

  Based on the above situation, the object of the present invention is to provide plastics having characteristics corresponding to various uses by material recycling even with alloy resins (PC + ABS resins) of incompatible polycarbonate resin and acrylonitrile-butadiene-styrene resin. The object of the present invention is to provide a method for efficiently recycling plastic waste by reducing the amount of plastic waste that can be obtained by thermal recycling.

  Furthermore, another subject of this invention is providing the plastic molding which has the characteristic according to various uses by material recycling from a plastic waste material.

  The inventors of the present invention are that the properties of the polycarbonate resin and the acrylonitrile-butadiene-styrene resin (PC + ABS resin) alone are significantly reduced as compared with the virgin material, and the polycarbonate resin is difficult to recycle due to its chemical structure. , And the fact that the polycarbonate resin and acrylonitrile-butadiene-styrene resin are incompatible, mixing another base material (resin) that is easily compatible with PC + ABS resin, and the polycarbonate resin and acrylonitrile-butadiene-styrene resin By adding components that are easy to adapt to both, the idea of resolving the physical properties of the waste material and recovering the reduced physical properties is the idea that the above problem can be solved, and a method for recycling plastic waste materials Conducted experiments on physical properties to develop It was repeated 討. That is, the present invention is as follows.

  The plastic waste material recycling method of the present invention is a plastic waste material recycling method of alloy resin of polycarbonate resin and acrylonitrile-butadiene-styrene resin, wherein the alloy resin and acrylonitrile-butadiene-styrene resin are mixed. Including the step of:

  In the plastic waste recycling method of the present invention, the mixing ratio of the alloy resin and acrylonitrile-butadiene-styrene resin is 50 when the total weight of the alloy resin and acrylonitrile-butadiene-styrene resin is 100. It is preferable that it is the ratio used as the above.

  In the method for recycling plastic waste material according to the present invention, when the alloy resin and acrylonitrile-butadiene-styrene resin are mixed, the total weight of the alloy resin and acrylonitrile-butadiene-styrene resin is 100, and the acrylonitrile-butadiene-styrene resin is 50. When the ratio is as described above, it is preferable to add a component that is easily compatible with both the alloy resin and the acrylonitrile-butadiene-styrene resin. Here, the components that are easily compatible with both the alloy resin and the acrylonitrile-butadiene-styrene resin are a rubber component inside, and a core portion that constitutes a compatible component of the alloy resin and acrylonitrile-butadiene-styrene resin in the outer shell, and It is preferable to have a core-shell structure having a shell portion. In this case, the component of the core part is at least one selected from a butadiene system, an acrylic system, and a silicone-acrylic composite system, and the component of the shell part is at least any selected from an acrylic system and an acrylonitrile-styrene system. It is preferable that

  The acrylonitrile-butadiene-styrene resin to be mixed with the alloy resin in the plastic waste material recycling method of the present invention may be any of virgin materials and acrylonitrile-butadiene-styrene resins obtained from plastic waste materials.

  In the plastic waste material recycling method of the present invention, at least one of the alloy resin waste material and the acrylonitrile-butadiene-styrene resin waste material is selected from the group consisting of home appliances, OA equipment, and electrical and electronic parts. It is preferably at least one of them or a part of a product on which a flat panel display is mounted. Further, the product on which the flat panel display is mounted is preferably at least one selected from a liquid crystal display, a plasma display, an organic EL display, an inorganic EL display, a field emission display, and electronic paper.

  The present invention also provides a method for producing a plastic molded body, including the above-described method for recycling plastic waste materials according to the present invention.

  The present invention further provides a plastic molded body produced by the above-described method for producing a plastic molded body of the present invention.

  The plastic molded body of the present invention is preferably used for products that are material recycled. The material recycled is preferably at least one selected from the group consisting of home appliances, OA equipment, and electrical / electronic parts, or a product part on which a flat panel display is mounted. Further, the product on which the flat panel display is mounted is preferably at least one selected from a liquid crystal display, a plasma display, an organic EL display, an inorganic EL display, a field emission display, and electronic paper.

  According to the plastic waste material recycling method of the present invention, plastic waste material formed from an alloy resin of polycarbonate resin and acrylonitrile-butadiene-styrene resin, which is originally difficult to recycle materials, can be efficiently recycled. Therefore, it is possible to obtain a plastic molded body having characteristics according to various uses, and it is possible to reduce plastic waste materials that are thermally recycled.

  Further, according to the method for recycling plastic waste material of the present invention, acrylonitrile-butadiene-styrene resin (ABS resin) is formed on a plastic waste material formed of an alloy resin (PC + ABS resin) of polycarbonate resin and acrylonitrile-butadiene-styrene resin. Mix. In general, acrylonitrile-butadiene-styrene resin (ABS resin) has a lower resin melting temperature than an alloy resin (PC + ABS resin) of polycarbonate resin and acrylonitrile-butadiene-styrene resin. Since the resin melting temperature can be lowered at the time of molding, it leads to energy saving during molding. Furthermore, since the molding time can be shortened by lowering the resin melting temperature, it can contribute to productivity improvement.

  And by the manufacturing method of the plastic molding of this invention, material recycling which uses a plastic waste material as a main raw material can be performed, and the plastic molding which has the characteristic suitable for various uses can be provided.

<Plastic waste>
The method for recycling plastic waste material according to the present invention targets plastic waste material (plastic product waste) of alloy resin of polycarbonate resin and acrylonitrile-butadiene-styrene resin.

  The plastic waste material in the plastic waste material recycling method of the present invention is preferably at least one waste selected from the group consisting of home appliances, OA equipment, and electrical and electronic parts. The household appliances are products selected from the group consisting of air conditioners, television sets, refrigerators, washing machines, etc., and particularly include members made of plastic containing flame retardants used in liquid crystal television sets, copying machines, etc. It is. In many cases, an alloy resin made of polycarbonate resin and acrylonitrile-butadiene-styrene resin is used as the plastic material collected from the cabinets of liquid crystal televisions and copying machines discarded as used products.

  The plastic waste recycling method of the present invention can also be applied to plastic waste recovered from products (FPD products) equipped with flat panel displays (FPD), which have recently been on an expanding trend. Recycling of waste materials can be achieved. In this case, the flat panel display product is preferably at least one selected from a liquid crystal display, a plasma display, an organic EL display, an inorganic EL display, a field emission display, and electronic paper.

  In the present specification, when referring to “plastic” or “thermoplastic resin”, not only the composition of a thermoplastic resin in a narrow sense is shown, but also a thermoplastic elastomer composition and a polymer composition, etc. The composition of the thermoplastic resin in the broad meaning to include shall be shown.

<Procedure for recycling used LCD TV cabinets>
FIG. 1 is a flowchart showing a preferred example of the plastic waste material recycling method of the present invention. Hereinafter, a case where the plastic waste material is a liquid crystal television cabinet, which is a specifically used product, will be described as an example, and the plastic waste material recycling method of the present invention will be described in detail with reference to FIG. The cabinet of the liquid crystal television is formed of, for example, an alloy resin (PC + ABS resin) of polycarbonate resin and acrylonitrile-butadiene-styrene resin or acrylonitrile-butadiene-styrene resin (ABS resin).

  First, a cabinet (material is an alloy resin of polycarbonate resin and acrylonitrile-butadiene-styrene resin (PC + ABS resin) and acrylonitrile-butadiene-styrene resin (ABS resin)) is collected from the used liquid crystal television (step S1). Since the cabinet is usually fixed with a plurality of screws, the housing can be removed by removing the screws using a screwdriver.

  Here, in FIG. 1, both the waste material of the polycarbonate resin and the acrylonitrile-butadiene-styrene resin alloy resin (PC + ABS waste material) and the waste material of the acrylonitrile-butadiene-styrene resin (ABS waste material) are recovered. Although the case is given as an example, it is sufficient that at least the PC + ABS waste material to be recycled is recovered in the process, and the ABS waste material is not recovered in the process. In the mixing process (step S8) described later, acrylonitrile is collected. -A butadiene-styrene resin virgin material may be mixed.

  Next, a material different from the cabinet (referred to as “different material”) is removed (step S2). Examples of the different material include a seal attached to a cabinet, a logo batch, a vibration preventing tape, a cord binding band, and the like. The front cabinet is often painted, but the coating is also made of a different material. It is preferable to remove these foreign materials because they are a cause of deterioration in physical properties. The method for removing foreign materials from the cabinet is not particularly limited, such as mechanical methods such as cutting and polishing, and removal using chemicals, and conventionally known methods can be used as appropriate.

  Next, the cabinet is crushed to about 10 mm (step S3). Thereafter, the cabinet crushed material is washed to remove attached dirt, dust, foreign matter, and the like (step S4). Examples of the method for washing the crushed cabinet include a dry method for removing foreign matters by rubbing crushed resins and a wet method such as water washing, but the method is not particularly limited. Conventionally known methods can be appropriately used.

  Next, the washed cabinet crushed material is dried (step S5). An alloy resin (PC + ABS resin) of a polycarbonate resin and an acrylonitrile-butadiene-styrene resin is a resin that is relatively susceptible to hydrolysis, and thus is preferably dried. The drying conditions are, for example, about 4 to 6 hours at 80 ° C., but are not particularly limited. Moreover, also about drying equipment, although a thermostat, a dehumidification dryer, a hot air dryer etc. are mentioned, it does not specifically limit also about this.

  Next, a small amount of the dried resin material (PC + ABS resin and ABS resin) is extracted and a lot inspection is performed (step S6). Thereby, it becomes possible to grasp the characteristics of plastic waste materials (PC + ABS waste materials, ABS waste materials) and formulate a characteristic improvement prescription. The inspection items include, for example, mechanical properties such as tensile strength, tensile elongation, bending strength, bending elastic modulus, impact strength, flow characteristics, flame retardancy, and the like. As described above, the ABS resin may be either a waste material or a virgin material. When a virgin material is used, only the PC + ABS waste material needs to be inspected.

  Next, a characteristic improvement prescription is determined based on the result of the lot inspection (step S7). Here, for example, the mixing ratio when mixing the PC + ABS resin and the ABS resin, the type and amount of the compatibilizer to be added, and the like are determined. Next, based on the determined property improvement formulation, PC + ABS resin (PC + ABS waste material) and ABS resin (ABS waste material or virgin material of ABS resin), compatibilizer (a component that is compatible with both PC + ABS resin and ABS resin), etc. Mix (step S8).

  Since PC + ABS resin and ABS resin are comparatively easy to blend in, it is effective to mix and recycle PC + ABS resin and ABS resin to improve mechanical properties, especially impact properties, compared to recycling PC + ABS resin alone. It is a technique. For example, when recycling PC + ABS waste, ABS resin can be used as an extender for PC + ABS waste. Further, depending on the grade of the ABS resin, it can be used as a PC + ABS resin.

  As for the mixing ratio of PC + ABS resin and ABS resin, if the weight of both is 100 and the PC + ABS resin is 50 or more, there is no need to add a compatibilizer, but the case of PC + ABS resin is less than 50. It is preferable to add a compatibilizing agent. This is because when the PC + ABS resin is less than 50, the compatibility between the PC + ABS resin and the ABS resin is deteriorated, and the impact characteristics may be greatly reduced.

  The type of the compatibilizer is preferably a core-shell structure in which a rubber component is formed in the inside (core portion) and a component that is easily compatible with both the PC + ABS resin and the ABS resin is formed in the outer shell (shell portion). Specifically, the component of the core part is at least one selected from a butadiene type, an acrylic type, and a silicone-acrylic composite type, and the component of the shell part is at least one selected from an acrylic type and an acrylonitrile-styrene type It is preferable that Acrylic and acrylonitrile-styrene are easy to be compatible with both polycarbonate resin and ABS resin, but acrylic is particularly easy to be compatible with polycarbonate resin, and acrylonitrile-styrene is particularly easy to use with ABS resin. When there are many resin components, it is preferable to select an acrylic type and when there are many ABS resins, an acrylonitrile-styrene type is selected.

  Of course, a commercially available product may be used as the compatibilizing agent. Specifically, methabrene C-223A (manufactured by Mitsubishi Rayon Co., Ltd.), C-323A (manufactured by Mitsubishi Rayon Co., Ltd.), E-901 (manufactured by Mitsubishi Rayon Co., Ltd.) ), W-450A (Mitsubishi Rayon Co., Ltd.), S-2001 (Mitsubishi Rayon Co., Ltd.), S-2006 (Mitsubishi Rayon Co., Ltd.), SRK-200 (Mitsubishi Rayon Co., Ltd.), SX-006 ( (Mitsubishi Rayon Co., Ltd.) and the like, but are not particularly limited.

  Next, a mixture of PC + ABS resin (PC + ABS waste material), ABS resin (ABS waste material or ABS resin virgin material), a compatibilizer, and the like is heated and melted to produce a pellet-shaped resin material for molding (step S9). Pellet manufacture can be performed with an extruder. The extruder is not particularly limited, and for example, a single screw extruder, a twin screw extruder, or a multi-screw extruder can be preferably used.

  When the mixture is formed into pellets and recycled, the material can be granulated by a method such as sheet cutting, strand cutting, hot air cutting or underwater cutting after extrusion. Further, when molding into a specific shape later by injection molding, the underwater cut method is particularly preferable in that the resin raw material can be supplied smoothly and processed in large quantities.

  The particle size of the pellet is preferably 1 mm or more, and more preferably 2 mm or more. The particle size of the pellet is preferably 8 mm or less, and more preferably 5 mm or less. When the particle size of the pellet is less than 1 mm, the workability is likely to be lowered because it is floating, and when the particle size of the pellet exceeds 8 mm, it is not sufficiently melted in the cylinder of the molding machine, so that uniform kneading becomes difficult. Prone.

  The shape of the molding resin raw material described above is not limited to a pellet shape, and may be a sheet shape, a film shape, a pipe shape, or the like. Therefore, it can be determined as appropriate from the type of the extruder, the mode of use or the required characteristics. In addition, additives such as heat stabilizers, light stabilizers, antistatic agents, lubricants, fillers, copper damage inhibitors, antibacterial agents, colorants, flame retardants, etc., may be added to the above-mentioned molding resin raw materials, if necessary. It can be added in an amount that does not impair the effects of the invention.

  In order to simplify the manufacturing process of plastic members, it is possible to directly produce plastic members by directly putting crushed plastic into an injection molding machine without molding into pellets, but in the case of PC + ABS resin Further, from the viewpoint that the acrylonitrile-butadiene-styrene resin can be dispersed in the polycarbonate resin by the shearing force due to the extrusion process, further, when an additive such as a compatibilizing agent is mixed, the extrusion process is performed. From the viewpoint that it can be blended more uniformly, it is preferable to produce pellets by extrusion.

  Next, the resin material in the form of pellets is heated and melted with an injection molding machine to produce a plastic molded body (step S10). Although it does not specifically limit as an injection molding machine, For example, a screw in-line type injection molding machine or a plunger type injection molding machine etc. are mentioned.

<Plastic molded body manufacturing method, plastic molded body>
The present invention also provides a method for producing a plastic molded body including the above-described method for recycling plastic waste materials according to the present invention. Processes other than the above-described method for recycling plastic waste of the present invention in the method for producing a plastic molded body of the present invention can be combined with known processes as appropriate, and are not particularly limited. Furthermore, the present invention also provides a plastic molded body produced by the above-described method for producing a plastic molded body of the present invention.

  The plastic molded article of the present invention is preferably used for a product that is material-recycled. In this case, the product that is material-recycled is selected from the group consisting of home appliances, OA equipment, and electrical and electronic parts. It is preferable that at least one of the above. The material recycled product may be a part of a product on which a flat panel display is mounted. In this case, the product on which the flat panel display is mounted is a liquid crystal display, a plasma display, an organic EL display, or an inorganic EL display. It is preferable that at least one selected from a field emission display and electronic paper.

  Hereinafter, although an example of an experiment is given and the present invention is explained in detail, the present invention is not limited to these.

<Experimental example 1>
The recovered liquid crystal television (manufactured five years from the date of manufacture) is dismantled by hand, and the housing cabinet (PC + ABS waste material) is made of a polycarbonate resin and acrylonitrile-butadiene-styrene resin alloy resin (PC + ABS resin). The waste of Psycholoy C6600, made by SABIC Innovative Plastics, was collected. Thereafter, the attached matter such as the label was removed and crushed, and then washed with water. On the other hand, acrylonitrile-butadiene-styrene resin was prepared as a virgin material (Terlan GP35, manufactured by BASF) (hereinafter referred to as “ABS virgin material”). Next, the PC + ABS waste material and the ABS virgin material were dried by a dehumidifying dryer (manufactured by Matsui Seisakusho Co., Ltd.) and then mixed at a predetermined ratio together with a compatibilizing agent (methabrene C-223A, manufactured by Mitsubishi Rayon) (Example 1). ~ 6, Comparative Examples 1 to 4), and then using a twin screw melt kneading extruder (manufactured by Technobel Co., Ltd.) having a screw diameter of 25 mm and L / D = 26), heating and kneading at a set temperature of 230 ° C Extrusion molding was performed using a pelletizer to obtain a pellet-shaped resin material for molding.

  Subsequently, this molding resin raw material waste material is put into a hopper of a 10-ton injection molding machine (manufactured by Nissei Plastic Industry Co., Ltd.), and the injection molding conditions are a molding temperature of 230 ° C., a mold temperature of 40 ° C., and a cooling time of 30 seconds. Thus, an ASTM-compliant test piece for measuring physical properties was prepared. In addition, a test piece for measuring physical properties having a thickness of 3 mm was also prepared for measuring the surface impact strength. And using each of these test pieces, the tensile strength, elongation, bending strength, bending elastic modulus, Izod impact strength, and surface impact strength described later were measured.

<Method for measuring physical properties>
(1) Tensile strength (MPa) and elongation (%)
The tensile strength at break and the elongation at break were measured according to JIS K7113. In addition, “tensile strength” and “elongation” are materials that are tensioned at a constant speed, and the relationship between stress and strain is obtained. The stretched material first undergoes elastic deformation, then plastic deformation, When the maximum strength is reached and the yield point is exceeded, necking occurs and breaks. The place where the stress is greatest (maximum point stress) is called “tensile strength”, and the strain at break (elongation at break) is called “elongation”.

(2) Flexural strength (MPa) and flexural modulus (MPa)
Measurements were made in accordance with JIS K7203. “Bending strength” and “flexural modulus” are obtained by applying a stress to the center of a test piece supported at two points to obtain a relationship between stress and strain. The place where the stress is greatest is called “bending strength”, and the slope of the stress-strain curve is called “flexural modulus”.

(3) Notched Izod impact strength (KJ / m ² )
The measurement was performed in accordance with JIS K7110.

(4) Surface impact strength (cm)
The measurement was performed in accordance with JIS K7211.

  The physical property measurement results of Experimental Example 1 are shown in Table 1 (Examples 1 to 6) and Table 2 (Comparative Examples 1 to 4). From Tables 1 and 2, when the weight of the PC + ABS waste material and the ABS virgin material is 100, and the PC + ABS waste material is 50 and 75, no significant deterioration in physical properties is observed, even if no compatibilizer is added. On the other hand, when the weight of the PC + ABS waste material and the ABS virgin material was 100, and the PC + ABS waste material was 25, the Izod impact strength was significantly reduced without the addition of the compatibilizer. On the other hand, when the compatibilizing agent was added, the strength was significantly improved.

<Experimental example 2>
Next, the ABS virgin material used in Experimental Example 1 was replaced with the ABS waste material (five years from the date of manufacture) used in the air conditioner casing parts (Terlan GP35, manufactured by BASF). Similarly, the same experiment as in Experimental Example 1 was performed except that the cleaning was performed (Examples 7 to 12 and Comparative Examples 5 to 8). The physical property measurement results of Experimental Example 2 are shown in Table 3 (Examples 7 to 12) and Table 4 (Comparative Examples 5 to 8). As a result, the same results as in Experimental Example 1 were obtained.

  The method for recycling plastic waste materials according to the present invention is not limited to the method for recycling plastic waste materials collected from household electrical appliances, OA equipment, and electrical / electronic components, but is a polycarbonate resin and acrylonitrile-butadiene-styrene resin. Any product can be suitably applied as long as it is a product including a member composed of an alloy resin (PC + ABS resin).

  The embodiments and experimental examples disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

  According to the method for recycling plastic waste material of the present invention, plastic waste material formed of an alloy resin (PC + ABS resin) of polycarbonate resin and acrylonitrile-butadiene-styrene resin, which is difficult to be recycled, can be efficiently recycled. Therefore, it is possible to obtain a plastic molded body having characteristics according to various uses, and it is possible to reduce plastic waste materials that are thermally recycled.

  Further, according to the method for recycling plastic waste material of the present invention, acrylonitrile-butadiene-styrene resin (ABS resin) is formed on a plastic waste material formed of an alloy resin (PC + ABS resin) of polycarbonate resin and acrylonitrile-butadiene-styrene resin. Mix. Generally, acrylonitrile-butadiene-styrene resin (ABS resin) has a lower resin melting temperature than an alloy resin (PC + ABS resin) of polycarbonate resin and acrylonitrile-butadiene-styrene resin. In addition, the resin melting temperature can be lowered, leading to energy saving during molding. Furthermore, since the molding time can be shortened by lowering the resin melting temperature, it can contribute to productivity improvement.

  And by the manufacturing method of the plastic molding of this invention, material recycling which uses a plastic waste material as a main raw material can be performed, and the plastic molding which has the characteristic suitable for various uses can be provided.

It is a flowchart which shows a preferable example of the recycling method of the plastic waste material of this invention.

Claims (16)

  A method for recycling plastic waste of alloy resin of polycarbonate resin and acrylonitrile-butadiene-styrene resin, comprising the step of mixing said alloy resin and acrylonitrile-butadiene-styrene resin. .   The mixing ratio of the alloy resin and acrylonitrile-butadiene-styrene resin is a ratio in which the alloy resin becomes 50 or more when the total weight of the alloy resin and acrylonitrile-butadiene-styrene resin is 100. The method of recycling plastic waste materials described.   In the mixing of the alloy resin and acrylonitrile-butadiene-styrene resin, when the total weight of the alloy resin and acrylonitrile-butadiene-styrene resin is 100 and the ratio of acrylonitrile-butadiene-styrene resin is 50 or more, the compatibilizing agent The method for recycling plastic waste materials according to claim 1, wherein:   The compatibilizer comprises a core-shell structure having a core part and a shell part, wherein the compatibilizer comprises a rubber component inside and an outer shell made of a compatible component of alloy resin and acrylonitrile-butadiene-styrene resin. The method of recycling plastic waste materials described.   The component of the core part is at least one selected from butadiene, acrylic, and silicone-acrylic composites, and the component of the shell is at least one selected from acrylic and acrylonitrile-styrene. The method for recycling plastic waste materials according to claim 4.   The method for recycling plastic waste materials according to any one of claims 1 to 5, wherein the acrylonitrile-butadiene-styrene resin mixed with the alloy resin is a virgin material.   The method for recycling plastic waste material according to any one of claims 1 to 5, wherein the acrylonitrile-butadiene-styrene resin to be mixed with the alloy resin is obtained from plastic waste material.   The waste material of the alloy resin and at least one of the waste material of acrylonitrile-butadiene-styrene resin are at least one selected from the group consisting of home appliances, OA equipment, and electrical and electronic parts. How to recycle plastic waste.   8. The plastic waste material recycling method according to claim 7, wherein at least one of the alloy resin waste material and the acrylonitrile-butadiene-styrene resin waste material is a part of a product on which a flat panel display is mounted.   The recycled plastic waste material according to claim 9, wherein the product on which the flat panel display is mounted is at least one selected from a liquid crystal display, a plasma display, an organic EL display, an inorganic EL display, a field emission display, and electronic paper. Recycling method.   The manufacturing method of a plastic molding containing the recycling method of the plastic waste material in any one of Claims 1-10.   A plastic molded body produced by the method for producing a plastic molded body according to claim 11.   The plastic molded body according to claim 12, which is used for a product to be recycled.   The plastic molded body according to claim 13, wherein the product to be material-recycled is at least one selected from the group consisting of home appliances, OA equipment, and electrical and electronic parts.   The plastic molded body according to claim 13, wherein the product to be material-recycled is a part of a product on which a flat panel display is mounted.   The plastic molded body according to claim 15, wherein the product on which the flat panel display is mounted is at least one selected from a liquid crystal display, a plasma display, an organic EL display, an inorganic EL display, a field emission display, and electronic paper.

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