JP4556503B2 - Recycled styrene resin composition and molded product - Google Patents

Description

The present invention relates to a recycled styrene-based resin composition comprising an impact-resistant reinforcing material for resin blending, which is useful as a resin blending material for recycling and recycling waste polystyrene and waste impact-resistant polystyrene, and the recycled styrene-based resin composition. The present invention relates to a regenerated styrene resin molded product formed by molding a resin composition.

  Polystyrene has excellent transparency and appearance, has high tensile strength and rigidity, and is widely used in the fields of food containers, stationery, miscellaneous goods, etc., but has a drawback of low impact resistance. For this reason, impact resistant polystyrene reinforced with a rubber component to improve impact resistance has been developed and widely used in home appliances, OA equipment, machine parts, and the like.

  As the high impact polystyrene, in the early stages of its development, a method of simply blending polystyrene with a rubbery polymer such as polybutadiene or styrene / butadiene copolymer has been proposed. However, there is a drawback in that sufficient impact resistance cannot be obtained due to poor affinity at the interface between the rubber phase and the resin phase. Therefore, currently, impact-resistant polystyrene is a bulk polymerization method in which an uncrosslinked rubber polymer is dissolved in a styrene monomer and polymerization is performed as it is, or suspension polymerization is performed after preliminary polymerization is performed. It is produced by a polymerization method (see, for example, Patent Document 1).

On the other hand, ABS has excellent processability and appearance, has higher tensile strength and rigidity than polystyrene, and has excellent heat resistance and chemical resistance. Although used, there is a drawback that the thermal stability is low. Therefore, application of various heat stabilizers and the like has been attempted, and ABS with improved heat stability has been developed and has been widely used in automobile parts, home appliances, OA equipment, machine parts, and the like.
JP-A-5-320272

  In recent years, the demand for recycling plastic products such as polystyrene, impact-resistant polystyrene, and ABS has increased due to recent environmental countermeasures, and it is already indispensable due to the enforcement of the Home Appliance Recycling Law, but the recycling system is still perfect. There is no situation.

The present invention has been made in view of the above-described conventional situation, and retains the characteristics of polystyrene, high-impact polystyrene, or a resin in which ABS is mixed with this, and has high impact strength that cannot be obtained by the prior art. Recycled styrene resin with various physical properties balance from waste polystyrene, waste impact-resistant polystyrene, or waste resin mixed with waste ABS using waste resin recycled material that can produce recycled styrene resin It aims at providing a composition and a molded article.

The regenerated styrene resin composition of the present invention comprises a rubber polymer having a gel content of 40 to 98% by mass and an average particle size of 100 to 550 nm, mainly composed of an aromatic vinyl compound, and 0.1 % of a vinyl cyanide compound. The impregnation step of impregnating the monomer component containing 10 mass% , and then using the oil-soluble pyrolysis initiator having a 10-hour half-life temperature of 30 to 90 ° C., the monomer is added to the rubber polymer. A graft polymer produced through a polymerization step of graft-polymerizing the components, and graft-polymerizing 70 to 20 parts by mass of the monomer component to 30 to 80 parts by mass (in terms of solid content) of the rubbery polymer Waste resin containing an impact-resistant reinforcing material for compounding a resin comprising a graft polymer having a mass average molecular weight of 40,000 to 200,000 (however, the total of the rubbery polymer and the monomer component is 100 parts by mass) Recycled materials and waste Polystyrene and / or Hai耐impact polystyrene, or at least one is characterized by comprising a mixed resin of the waste polystyrene and / or Hai耐impact polystyrene and ABS is spent resin by melt mixing.

The rubbery polymer of this, polybutadiene, styrene-butadiene-alpha-olefin copolymer, an ethylene-alpha-olefin non-conjugated diene copolymer, and one or more selected from the group consisting of acrylic rubber Is mentioned .

The recycled styrene-based resin composition of the present invention includes waste polystyrene and / or waste impact-resistant polystyrene, or a mixture resin of waste polystyrene and / or waste impact-resistant polystyrene and ABS, at least one of which is a waste resin, and the present invention. It is characterized in that it is obtained by melt-mixing the impact-resistant reinforcing material for resin blending and, if necessary, the resin blending reforming material of the present invention.

  The regenerated styrenic resin molded product of the present invention is formed by molding such a regenerated styrene resin composition of the present invention.

According to the recycled material of the waste resin of the present invention, the surface appearance and the high impact strength that are remarkably superior to the recycled styrene resin produced by the prior art can be obtained simply by mechanically melting and mixing this with the waste resin. Recycled styrenic resin having various physical property balances can be produced.

The recycled material of the waste resin of the present invention can easily produce a recycled styrene-based resin excellent in the balance of physical properties such as surface appearance, impact resistance and rigidity, without restriction on the mixing ratio with respect to the waste resin. By mixing waste ABS, it is possible to increase impact resistance rather than virgin resin, which is useful for recycling waste polystyrene, waste impact polystyrene, and waste ABS.

  Hereinafter, embodiments of the present invention will be described in detail.

[Impact-resistant reinforcement for compounding resin]
First, the impact-resistant reinforcing material for resin blending of the present invention will be described in accordance with its production procedure.

  The impact-strengthening reinforcing material for resin blending of the present invention comprises an impregnation step of impregnating (occluding) a monomer component into a specific rubber polymer, and then using a specific polymerization initiator to form a rubber polymer. It is produced through a polymerization process in which a monomer component is graft-polymerized.

  The rubbery polymer used here has a gel content of 40 to 98% by mass, preferably 50 to 95% by mass, and an average particle size of 100 to 550 nm, preferably 150 to 450 nm. When the gel content of the rubbery polymer is less than 40% by mass, the surface appearance of the resin product using the resulting impact-resistant reinforcing material for resin compounding deteriorates, and when it exceeds 98% by mass, sufficient impact resistance is obtained. It tends to be impossible. Also, if the average particle size of the rubbery polymer is less than 100 nm, sufficient impact resistance cannot be obtained for the resin product using the obtained impact-resistant reinforcing material for resin blending, and if it exceeds 550 nm, a stable latex is obtained. There is no tendency. The rubbery polymer may have a single particle size distribution or a plurality of distributions.

  In the present specification, the gel content of the rubbery polymer means that the powdery rubbery polymer is immersed in toluene at 80 ° C. for 24 hours and then filtered through a 200 mesh wire mesh. It is the value obtained by calculating | requiring the ratio (mass%) of the insoluble matter which remained in.

  Specific examples of such a rubbery polymer include polybutadiene, styrene / butadiene copolymer, acrylonitrile / butadiene copolymer, ethylene / α-olefin copolymer, ethylene / α-olefin non-conjugated diene copolymer, An acrylic rubber etc. can be mentioned. These may be used alone or in combination of two or more.

The monomer component impregnated and grafted on the rubber polymer contains 20% by mass or more, particularly 30% by mass or more of the aromatic vinyl compound as a main component, but also contains a vinyl cyanide compound and further necessary. Accordingly, other copolymerizable monomers described later may be included. The content of the vinyl cyanide compound in the monomer component is 0 . 1 to 10 wt%, good Mashiku is 0.5 to 7.5 mass%. By including a vinyl cyanide compound, the compatibility is improved and the impact resistance is improved. However, if the ratio is too large, the compatibility becomes insufficient and the impact resistance reinforcing effect cannot be obtained. There is a tendency.

  Specific examples of the aromatic vinyl compound in the monomer component include styrene, α-methylstyrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, dimethylstyrene, t-butylstyrene, chlorostyrene, distyrene. Examples include chlorostyrene, bromostyrene, and dibromostyrene, and styrene is particularly preferable. These may be used alone or in combination of two or more.

  Specific examples of the vinyl cyanide compound include acrylonitrile and methacrylonitrile, and acrylonitrile is particularly preferable. These may be used alone or in combination of two or more.

  Furthermore, the monomer component can contain other monomers copolymerizable with the aromatic vinyl compound and the vinyl cyanide compound within a range that does not hinder the object of the present invention. Examples of other monomers include methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, amyl acrylate, hexyl acrylate, octyl acrylate, 2-ethylhexyl acrylate, cyclohexyl acrylate, dodecyl acrylate, octadecyl acrylate, phenyl acrylate, and benzyl acrylate. Acrylic acid ester of; methyl methacrylate, ethyl methacrylate, propyl methacrylate, butyl methacrylate, amyl methacrylate, hexyl methacrylate, octyl methacrylate, 2-ethylhexyl methacrylate, cyclohexyl methacrylate, dodecyl methacrylate, octadecyl methacrylate, phenyl methacrylate, benzyl methacrylate Any methacrylic acid ester; unsaturated acid anhydride such as maleic anhydride, itaconic anhydride and citraconic anhydride; unsaturated acid such as acrylic acid and methacrylic acid; maleimide, N-methylmaleimide, N-butylmaleimide, N- ( p-methylphenyl) maleimide, N-phenylmaleimide, N-cyclohexylmaleimide and other α- or β-unsaturated dicarboxylic acid imide compounds (also referred to as maleimide monomers); glycidyl methacrylate, allyl glycidyl ether and other epoxy compounds Unsaturated carboxylic acid amides such as acrylamide and methacrylamide; amino group-containing unsaturated compounds such as acrylic amine, aminomethyl methacrylate, aminoethyl methacrylate, aminopropyl methacrylate, and aminostyrene, 3-hydroxy-1-propene 4-hydroxy-1-butene, cis-4-hydroxy-2-butene, trans-4-hydroxy-2-butene, 3-hydroxy-2-methyl-1-propene, 2-hydroxyethyl acrylate, 2-hydroxy Examples thereof include hydroxyl group-containing unsaturated compounds such as ethyl methacrylate; oxazoline group-containing unsaturated compounds such as vinyl oxazoline. Moreover, these monomers may be used individually by 1 type, and may be used in combination of 2 or more type.

  In order to produce the reinforcing material of the present invention, first, the above-mentioned rubbery polymer is impregnated with the monomer component. In this impregnation step, the impregnation temperature is preferably 40 to 80 ° C, and more preferably 50 to 70 ° C. The impregnation time is preferably 15 to 90 minutes, more preferably 30 to 60 minutes. If the impregnation time and the impregnation temperature are out of this range, there is a possibility that a sufficient reinforcing effect is not exhibited with respect to the finally obtained resin composition.

  In this way, in the polymerization step after impregnating the monomer component inside the rubber polymer, graft polymerization is performed using an oil-soluble pyrolysis initiator having a 10-hour half-life temperature of 30 to 90 ° C. I do. Oil-soluble pyrolyzable initiators having a 10-hour half-life temperature of less than 30 ° C have safety problems, and those exceeding 90 ° C tend not to have a sufficient impact resistance reinforcing effect. Furthermore, when the 10-hour half-life temperature is out of the above range, it becomes difficult to obtain a target graft copolymer having a weight average molecular weight of 40,000 to 200,000.

  Specific examples of such oil-soluble pyrolysis initiators include benzoyl peroxide, lauroyl peroxide, di-2-ethylhexyl peroxydicarbonate, di-isopropyl peroxydicarbonate, t-butylperoxyneodecanate. , T-butyl peroxypivalate, t-hexyl peroxypivalate, azoisobutyl nitrile, and the like. These can be used alone or in combination of two or more.

  As the polymerization method, various known methods such as an addition polymerization method, for example, an emulsion polymerization method, a solution polymerization method, a bulk polymerization method, a bulk suspension polymerization method and the like can be adopted. In particular, since the polymerization can be easily controlled, emulsification is performed. A polymerization method is preferred. In addition, the above polymerization may be performed in one stage or in multiple stages.

  The ratio of the rubbery polymer and the monomer component used for the polymerization is 70 to 20 parts by mass of the monomer component (provided that the rubber is 30 to 80 parts by mass (solid content conversion)). 100 parts by weight in total of the polymer and the monomer component). When the proportion of the rubbery polymer is less than 30 parts by mass and the monomer component exceeds 70 parts by mass, the rubber content of the obtained reinforcing material is too small, and it is possible to obtain a reinforcing material excellent in impact resistance reinforcing effect. In the case where the rubbery polymer exceeds 80 parts by mass and the monomer component is less than 20 parts by mass, a sufficient impact resistance reinforcing effect cannot be obtained. A more preferable graft polymerization ratio is 60 to 30 parts by mass of the monomer component with respect to 40 to 70 parts by mass (in terms of solid content) of the rubber-like polymer. Therefore, in the above-described impregnation step, it is preferable that the rubbery polymer and the monomer component are supplied to the impregnation step in such a ratio, and then the polymerization step is performed.

  The polymerization conditions such as polymerization temperature and polymerization time can be arbitrarily set from the viewpoint of safety and efficiency.

  The thus obtained graft polymer constituting the reinforcing material of the present invention has a mass average molecular weight of 40000-200000, more preferably 60000-170000. When the mass average molecular weight is out of the above range, the resin composition using the same tends to be inferior in impact strength and fluidity.

  In order to measure the mass average molecular weight of the graft polymer, first, the graft polymer was put into tetrahydrofuran (hereinafter abbreviated as THF) and allowed to stand overnight. After the body is completely eluted, it is centrifuged at 12,000 rpm for 1 hour using a centrifuge to obtain a THF-insoluble matter (graft). Next, the THF-insoluble matter is dispersed in chloroform, the rubber is decomposed by ozonolysis, the graft chain is recovered and evaporated to dryness, and this is dissolved in THF to obtain a THF solution. And the THF solution which melt | dissolved this graft body is used as a sample, and the molecular weight of styrene conversion is measured by gel permeation chromatography (GPC).

  Moreover, it is preferable that the polymer of a monomer component is formed in the range of 10-60 mass% of internal components in the rubbery polymer which comprises the reinforcing material of this invention, and 20-50 mass. % Is more preferable (hereinafter, the internal abundance of the monomer component of the graft polymer is simply referred to as “internal abundance”). When the internal abundance is less than 10% by mass, the impact resistance of the resin composition using the reinforcing material of the present invention may not be improved. On the other hand, when it exceeds 60% by mass, the gloss may be lowered. is there. Here, the internal abundance is a polymer amount of a monomer component located inside the rubber polymer relative to the rubber polymer in the graft polymer, and is a value defined by the following formula (1). It is. The polymer of the monomer component located inside the rubber polymer may not be grafted to the rubber polymer. The amount of polymer of the monomer component located inside the rubber polymer is measured by measuring the particle size of the rubber polymer before impregnation and the expansion rate of the rubber polymer after graft polymerization as a simple calculation method. The internal residual rate of the monomer can be calculated from the volume increase rate.

  Further, the graft ratio of the graft polymer constituting the reinforcing material of the present invention is preferably 10 to 200% by mass, and more preferably 20 to 180% by mass. If the graft ratio is less than 10% by mass, the impact strength of the resin composition using the same may be lowered, and if it exceeds 200% by mass, the fluidity and impact resistance may be lowered. Here, the graft ratio is a value calculated by the following formula (2), and a measurement method can be appropriately selected depending on the type of the rubbery polymer. For example, in the case of polybutadiene, measurement by an ozonolysis method is possible. Can be obtained.

  Since the impact-resistant reinforcing material for resin blending of the present invention containing such a graft polymer has a smaller amount of an aromatic vinyl compound such as styrene included in the rubbery polymer than conventional impact-resistant polystyrene, Exhibits the superior properties of styrene and has a relatively small particle size of the dispersed rubber phase, so when mixed with waste polystyrene resins and these waste polystyrene resins and waste ABS, compared to conventional polystyrene resins A resin product having an excellent surface appearance can be obtained.

[Reformers for resin compounding]
The modifier for resin blending of the present invention includes a hard polymer obtained by polymerizing a monomer component mainly composed of an aromatic vinyl compound not containing a rubbery polymer.

  This monomer component does not contain a rubbery polymer, and is mainly composed of an aromatic vinyl compound, but also contains a vinyl cyanide compound and, if necessary, other copolymerizable monomers described later. You can leave. Content of the vinyl cyanide compound in a monomer component is 0-18 mass%, Preferably it is 0.1-10 mass%, More preferably, it is 0.5-7.5 mass%. By including a vinyl cyanide compound, the compatibility is improved and a sufficient reforming effect is obtained. However, when the ratio is too large, the compatibility is insufficient and the sufficient reforming effect tends not to be obtained.

  Specific examples of the aromatic vinyl compound in the monomer component include styrene, α-methylstyrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, dimethylstyrene, t-butylstyrene, chlorostyrene, distyrene. Examples include chlorostyrene, bromostyrene, and dibromostyrene, and styrene is particularly preferable. These may be used alone or in combination of two or more.

  Specific examples of the vinyl cyanide compound include acrylonitrile and methacrylonitrile, and acrylonitrile is particularly preferable. These may be used alone or in combination of two or more.

  Furthermore, the monomer component can contain other monomers copolymerizable with the aromatic vinyl compound and the vinyl cyanide compound within a range that does not hinder the object of the present invention. Examples of other monomers include methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, amyl acrylate, hexyl acrylate, octyl acrylate, 2-ethylhexyl acrylate, cyclohexyl acrylate, dodecyl acrylate, octadecyl acrylate, phenyl acrylate, and benzyl acrylate. Acrylic acid ester of; methyl methacrylate, ethyl methacrylate, propyl methacrylate, butyl methacrylate, amyl methacrylate, hexyl methacrylate, octyl methacrylate, 2-ethylhexyl methacrylate, cyclohexyl methacrylate, dodecyl methacrylate, octadecyl methacrylate, phenyl methacrylate, benzyl methacrylate Any methacrylic acid ester; unsaturated acid anhydride such as maleic anhydride, itaconic anhydride and citraconic anhydride; unsaturated acid such as acrylic acid and methacrylic acid; maleimide, N-methylmaleimide, N-butylmaleimide, N- ( p-methylphenyl) maleimide, N-phenylmaleimide, N-cyclohexylmaleimide and other α- or β-unsaturated dicarboxylic acid imide compounds (also referred to as maleimide monomers); glycidyl methacrylate, allyl glycidyl ether and other epoxy compounds Unsaturated carboxylic acid amides such as acrylamide and methacrylamide; amino group-containing unsaturated compounds such as acrylic amine, aminomethyl methacrylate, aminoethyl methacrylate, aminopropyl methacrylate, and aminostyrene, 3-hydroxy-1-propene 4-hydroxy-1-butene, cis-4-hydroxy-2-butene, trans-4-hydroxy-2-butene, 3-hydroxy-2-methyl-1-propene, 2-hydroxyethyl acrylate, 2-hydroxy Examples thereof include hydroxyl group-containing unsaturated compounds such as ethyl methacrylate; oxazoline group-containing unsaturated compounds such as vinyl oxazoline. Moreover, these monomers may be used individually by 1 type, and may be used in combination of 2 or more type.

  In order to produce the modifying material of the present invention, such a monomer component not containing a rubbery polymer is polymerized by a known polymerization method, for example, a polymerization method such as emulsion polymerization, suspension polymerization or bulk polymerization. A hard polymer is obtained.

  The polymerization initiator used for the polymerization of the monomer component is not particularly limited, such as water solubility and oil solubility, and can be selected according to the polymerization method.

  The polymerization conditions such as polymerization temperature and polymerization time can be arbitrarily set from the viewpoint of safety and efficiency.

  The thus obtained hard polymer constituting the modifier of the present invention preferably has a mass average molecular weight of 50,000 to 500,000, more preferably 100,000 to 450,000. When the mass average molecular weight is out of the above range, the resin composition using the same tends to be inferior in impact resistance and fluidity.

  In order to measure the mass average molecular weight of the hard polymer, the hard polymer was put into THF and allowed to stand overnight, and then subjected to an ultrasonic cleaner for 30 minutes to completely elute the solution. The sample may be used as a sample, and the molecular weight in terms of styrene may be measured by gel permeation chromatography (GPC).

[Waste resin]
In the present invention, the “waste resin” includes resin scraps (including lumps), pellets, surplus products, etc. that do not become products generated at the beginning or end of the resin production process. Further, in the process of molding the target molded product, unnecessary resin and resin molded products such as resin waste (including lumps) generated in various molding processes, non-conforming molded products, surplus molded products, and surplus pellets can be used.

  Resin parts of products that have finished their role in the market and unsold products are listed. For example, polystyrene used in cases such as food containers, stationery, foamed polystyrene, CD, MD, cassette tape, and miscellaneous goods. ABS, ASA, AES used in casings for impact-resistant polystyrene resins, automobile parts, home appliances, OA equipment, mechanical parts, etc. used in plastic resins, home appliances, OA equipment, machine parts, etc. Based resins and the like.

  Waste resin is used as resin generated in each process such as manufacturing and molding of these resins and the resin portion of products that have finished their role in the market. In the present invention, alloy materials in which these styrene resins are used, for example, alloy materials such as polycarbonate resins, polyphenylene resins, polyethylene terephthalate, polybutylene terephthalate resins, polyamide resins, and modified materials. Even the effect can be demonstrated.

[Recycled waste resin materials]
The recycled material for waste resin of the present invention includes the above-mentioned impact-resistant reinforcing material for resin blending and the modifier for resin blending of the present invention.

  In this recycled material, the content ratio of the reinforcing material and the modifying material is not particularly limited, and can be blended at an arbitrary ratio according to the blended amount of the waste resin and the desired characteristics.

  The recycled material of the present invention may be a material in which the reinforcing material and the modifying material of the present invention are mixed in advance at a predetermined ratio, or may be provided separately.

  Further, the recycled material of the present invention may contain various additives that are usually used as resin additives other than the reinforcing material and the modifying material of the present invention.

[Recycled styrene resin composition]
The regenerated styrene resin composition of the present invention is
(1) Waste polystyrene
(2) Waste impact resistant polystyrene
(3) Mixed resin of waste polystyrene and waste impact-resistant polystyrene
(4) Mixed resin of waste polystyrene and waste ABS
(5) Mixed resin of waste impact resistant polystyrene and waste ABS
(6) Mixed resin of waste polystyrene, waste impact polystyrene and waste ABS
(7) A mixed resin obtained by further mixing virgin resin of polystyrene and / or impact-resistant polystyrene with any of the above (1) to (6)
(8) The mixed resin obtained by further mixing ABS virgin resin with any of the above (1) to (7), the impact-resistant reinforcing material for resin blending of the present invention, or the impact-resistant reinforcing material for resin blending of the present invention (1) to (8) may be referred to as “waste resin” hereinafter .

In a further, reproduction styrenic resin composition of the present invention, these polystyrene-based, or may be blended with other thermoplastic resins other than ABS system. Other thermoplastic resins that can be blended with the regenerated styrene-based resin composition of the present invention are not particularly limited, and examples thereof include polycarbonate resins, polyphenylene ether resins, polyamide resins, polyethylene terephthalate resins, polybutylene terephthalate resins, and the like. Can be blended singly or in combination of two or more. These other thermoplastic resins can be blended according to the purpose. By blending these other thermoplastic resins, the application field of the regenerated styrene resin composition of the present invention is further broadened, and the recyclability is excellent.

  The blending amount of the reinforcing material and the modifying material of the present invention is such that desired physical properties can be obtained according to the type of resin blended therewith (the presence or absence of ABS, the proportion of ABS, the proportion of virgin resin, etc.). There is no particular limitation.

  The reinforcing material and the modifying material of the present invention can be blended in an arbitrary blending amount. However, when the reinforcing material and / or the modifying material of the present invention are blended in a normal case, the waste resin, the reinforcing material and the modifying material are modified. It is preferable to blend so that the reinforcing material and / or the modifying material may be 10 to 60 parts by mass, particularly 20 to 50 parts by mass in the total 100 parts by mass of the material.

  If the blending amount of the reinforcing material and the modifying material of the present invention is too small, it is not possible to obtain a sufficient reinforcing effect and reforming effect due to the blending of this, and if too much, the cost increases, and the waste resin It is unsuitable for reproduction and reuse.

  The melt mixing of the waste resin, the reinforcing material of the present invention, and the modifying material can be performed according to a conventional method using, for example, a ribbon blender, a Henschel mixer, a Banbury mixer, or the like.

  The regenerated styrene resin composition of the present invention may further contain other optional components as required in addition to the waste resin, the reinforcing material and the modifier of the present invention. Other optional components include, for example, external lubricants such as aliphatic carboxylic acid esters and paraffin, mold release agents, antistatic agents, ultraviolet absorbers, hindered phenol light stabilizers, glass fibers, flame retardant flame retardants (Halogen flame retardant, phosphorus flame retardant, antimony compound, etc.), various additives such as anti-drip agent, antibacterial agent, fungicide, silicone oil, coupling agent, colorant, etc. More than one species may be blended. The amount of these optional components added is not particularly limited as long as the characteristics of the regenerated styrene resin composition are maintained.

  The impact-resistant reinforcing material for resin blending of the present invention, or the impact-resistant reinforcing material for resin blending and modifying material of the present invention has good affinity for waste polystyrene, waste impact-resistant polystyrene, and waste ABS. The regenerated styrenic resin having various performances can be obtained by mixing these at an arbitrary ratio and by arbitrarily changing the mixing ratio to obtain a regenerated styrene resin composition having various physical property balances. The composition can be easily produced.

[Recycled styrene resin molded product]
The regenerated styrene resin molded product of the present invention is obtained by molding the regenerated styrene resin composition thus produced into a desired shape by a known molding method. For example, food containers, stationery, miscellaneous goods It is used in a wide range of fields such as automobile parts, home appliances, OA equipment, and machine parts, and its industrial utility value is extremely large.

  EXAMPLES Hereinafter, the present invention will be described more specifically with reference to production examples, examples, comparative examples, and reference examples. However, the present invention is not limited to the following examples unless it exceeds the gist. In the following, “part” and “%” are based on mass unless otherwise noted.

The methods for measuring various physical properties and characteristics in each example are as follows.
<Gel content of rubbery polymer>
The powdery rubbery polymer was immersed in toluene at 80 ° C. for 24 hours. Thereafter, the mixture was filtered through a 200-mesh wire mesh to determine the proportion (%) of toluene insoluble matter, and this was used as the gel content.
<Average particle diameter of rubbery polymer>
The particle size of the rubbery polymer before impregnation was dyed with osmic acid, and the particle size was measured with a transmission electron microscope (TEM).
<Mass average molecular weight of graft polymer>
The graft polymer was put in THF and allowed to stand overnight, and then subjected to an ultrasonic cleaner for 30 minutes to completely elute the graft body, and then centrifuged at 12,000 rpm for 1 hour using a centrifuge. A THF-insoluble matter (graft) was obtained. Next, the THF-insoluble matter was dispersed in chloroform, the rubber was decomposed by ozonolysis, the graft chain was recovered and evaporated to dryness, and this was dissolved in THF to obtain a THF solution. The THF solution in which this graft was dissolved was used as a sample, and the molecular weight in terms of styrene was measured by gel permeation chromatography (GPC).
<Graft ratio of graft polymer>
In the above-described procedure for measuring the weight average molecular weight of the graft polymer, centrifugal separation is performed in the same manner up to the THF-insoluble matter (graft body), and the THF-insoluble matter is extracted and the dry weight is measured. Next, this insoluble matter is dispersed in chloroform, the rubber is decomposed by ozonolysis, the graft chain is recovered, and the dry weight is measured. Thus, the monomer grafted to the rubber polymer was determined from the weight before ozonolysis (denominator of formula (2)) and the weight after ozonolysis (molecule of formula (2)).
<Internal abundance ratio of graft polymer>
The particle diameter of the rubber polymer before graft polymerization (before impregnation) was measured with a transmission electron microscope (TEM). Similarly, the particle diameter of the rubber polymer after graft polymerization was measured as TEM. Measured. When the monomer is present inside the rubbery polymer, the particle size becomes large. Therefore, the internal residual ratio of the monomer was determined from the average volume increase before and after the polymerization.
<Mass average molecular weight of hard polymer>
A hard polymer placed in THF and allowed to stand overnight is subjected to an ultrasonic cleaner for 30 minutes to completely elute it, and then this solution is used as a sample. Was measured.

[Production of graft polymer]
Production Example 1 (Example)
Polybutadiene-1 (gel content 94%, average particle size 290 nm) 50 parts, styrene 47.5 parts, acrylonitrile 2.5 parts (5% in the monomer component), t-dodecyl mercaptan 0.1 part, rosin A reactor was charged with 1.0 part of sodium acid, 0.05 part of potassium hydroxide and 160 parts of pure water, heated to 60 ° C. and impregnated for 60 minutes, and then t-hexyl peroxypivalate 0.3. Part was added, the temperature was raised to 75 ° C., and polymerization was carried out for 2 hours. An antioxidant was added to the obtained latex, and the mixture was poured into an aqueous calcium chloride solution to be solidified, washed, dehydrated and dried to obtain a graft polymer (A-1).

  Table 1 shows the mass average molecular weight, graft ratio, and internal abundance of the obtained graft polymer together with the polymerization conditions.

Production Example 2 (Example)
Polymerization was carried out in the same manner as in Example 1 except that the polymerization initiator was changed to azoisobutyl nitrile to obtain a graft polymer (A-2).

  Table 1 shows the mass average molecular weight, graft ratio, and internal abundance of the obtained graft polymer together with the polymerization conditions.

Production Example 3 (Example)
Polymerization was carried out in the same manner as in Example 1 except that the monomer component was changed to 45.0 parts of styrene and 5.0 parts of acrylonitrile (10% in the monomer component), and the graft polymer (A-3 )

  Table 1 shows the mass average molecular weight, graft ratio, and internal abundance of the obtained graft polymer together with the polymerization conditions.

Production Example 4 (Example)
Polymerization was performed in the same manner as in Example 1 except that polybutadiene-1 was changed to polybutadiene-2 (gel content: 85%, average particle size: 420 nm) to obtain a graft polymer (A-4).

  Table 1 shows the mass average molecular weight, graft ratio, and internal abundance of the obtained graft polymer together with the polymerization conditions.

Production Example 5 (Example)
Except having changed the impregnation time into 5 minutes, it superposed | polymerized like Example 1 and obtained the graft polymer (A-5).

  Table 1 shows the mass average molecular weight, graft ratio, and internal abundance of the obtained graft polymer together with the polymerization conditions.

Production Example 6 ( Comparative Example)
Except having changed the monomer component into 50.0 parts of styrene, it superposed | polymerized like Example 1 and obtained the graft polymer (A-6).

  Table 1 shows the mass average molecular weight, graft ratio, and internal abundance of the obtained graft polymer together with the polymerization conditions.

Production Example 7 (Comparative Example)
Polymerization was carried out in the same manner as in Example 1 except that the amount of acrylonitrile used was changed to 12.5 parts (25% in the monomer component) to obtain a graft polymer (A-7).

  Table 1 shows the mass average molecular weight, graft ratio, and internal abundance of the obtained graft polymer together with the polymerization conditions.

Production Example 8 (Comparative Example)
Except having changed the usage-amount of the rubber-like polymer of Example 1 into 25 parts, it superposed | polymerized like Example 1 and obtained the graft polymer (A-8).

  Table 1 shows the mass average molecular weight, graft ratio, and internal abundance of the obtained graft polymer together with the polymerization conditions.

Production Example 9 (Comparative Example)
Polymerization was performed in the same manner as in Example 1 except that polybutadiene-1 was changed to polybutadiene-3 (gel content: 98%, average particle size: 80 nm) to obtain a graft polymer (A-9).

  Table 1 shows the mass average molecular weight, graft ratio, and internal abundance of the obtained graft polymer together with the polymerization conditions.

Production Example 10 (Comparative Example)
Polymerization was performed in the same manner as in Example 1 except that the rubber polymer was changed to a rubber polymer having a gel content of 45% to obtain a graft polymer (A-10).

  Table 1 shows the mass average molecular weight, graft ratio, and internal abundance of the obtained graft polymer together with the polymerization conditions.

Production Example 11 (Comparative Example)
Example 1 except that the polymerization initiator was changed to cumene hydroperoxide and a catalyst (0.004 part of ferrous sulfate, 0.1 part of sodium pyrophosphate, 0.18 part of glucose) was added. Polymerization was carried out to obtain a graft polymer (A-11).

  Table 1 shows the mass average molecular weight, graft ratio, and internal abundance of the obtained graft polymer together with the polymerization conditions.

Production Example 12 (Comparative Example)
Polymerization was carried out in the same manner as in Example 1 except that the amount of t-dodecyl mercaptan was changed to 0.45 part to obtain a graft polymer (A-12).

  Table 1 shows the mass average molecular weight, graft ratio, and internal abundance of the obtained graft polymer together with the polymerization conditions.

Production Example 13 (Comparative Example)
Polymerization was carried out in the same manner as in Example 1 except that the rubber polymer was changed to a rubber polymer having an average particle diameter of 700 nm to obtain a graft polymer (A-13).

  Table 1 shows the mass average molecular weight, graft ratio, and internal abundance of the obtained graft polymer together with the polymerization conditions.

[Production of hard polymer]
Production Example 14 (Example)
A reactor was charged with 180 parts of pure water, 2.5 parts of sodium rosinate, and 0.05 parts of potassium hydroxide, heated to 75 ° C., 0.15 part of potassium persulfate was added, 95 parts of styrene, and acrylonitrile. 5 parts and 0.2 part of t-dodecyl mercaptan were added dropwise over 2 hours, and the mixture was allowed to stand for 1 hour after completion of the addition. The obtained latex was put into an aqueous calcium chloride solution to be coagulated, washed, dehydrated and dried to obtain a hard polymer (B-1).

  The mass average molecular weight of this hard polymer was 380000.

[Evaluation of reinforcements and modifiers]
Examples 1 to 10, Comparative Example 15
The graft polymer shown in Table 2 was mixed with various resins at the ratio shown in Table 2, 0.1 part of polyethylene wax was added, and the mixture was kneaded with a Banbury mixer to be pelletized. Using the obtained pellets, necessary test specimens were prepared by an injection molding machine (“J75E-P” type, manufactured by Nippon Steel Works). The obtained test pieces were evaluated as follows, and the results are shown in Table 2.
(Izod impact value)
The Izod impact value (J / m, 23 ° C.) was measured according to ASTM D256.
(Tensile strength)
Tensile strength (MPa) was measured according to ASTM D638.
(Surface gloss)
A test piece of 60 mm × 90 mm × 3 mm thickness was molded, and the gloss at the center of the test piece was measured at an incident angle of 60 ° using a digital variable angle gloss meter “UGV-4D” manufactured by Suga Test Instruments Co., Ltd.

Examples 11-16
Except that the graft polymer (A-1) and the hard polymer (B-1) were mixed with various resins in the proportions shown in Table 3, preparation and evaluation of the test piece were performed in the same manner as in Example 1, The results are shown in Table 3.

Comparative Examples 1-14
A test piece was prepared and evaluated in the same manner as in Example 1 except that the graft polymer shown in Table 4 was mixed with various resins and a hard polymer in the ratio shown in Table 4, and the results are shown in Table 4. .

Reference Examples 1-4
For the resins shown in Table 5, test pieces were prepared and evaluated in the same manner as in Example 1, and the results are shown in Table 5.

  As is clear from the above evaluation results, the regenerated styrene resin obtained by blending the impact-resistant reinforcing material for resin blending of the present invention, or the impact-resistant reinforcing material for resin blending of the present invention and a modifier, It had superior Izod impact strength than the impact-resistant polystyrene obtained by the prior art, and was excellent in tensile strength and surface appearance.

  Furthermore, by increasing the mixing ratio of the impact-resistant reinforcing material for resin blending according to the present invention, it was possible to obtain a regenerated styrene resin having a high impact strength that cannot be obtained by conventional impact-resistant polystyrene.

Claims (6)

A rubbery polymer having a gel content of 40 to 98% by mass and an average particle size of 100 to 550 nm is impregnated with a monomer component mainly composed of an aromatic vinyl compound and 0.1 to 10% by mass of a vinyl cyanide compound. Produced through an impregnation step, and then a polymerization step in which the monomer component is graft polymerized to the rubbery polymer using an oil-soluble pyrolysis initiator having a 10-hour half-life temperature of 30 to 90 ° C. A graft polymer obtained by graft-polymerizing 70 to 20 parts by mass of the monomer component to 30 to 80 parts by mass (in terms of solid content) of the rubbery polymer (provided that the rubber polymer and A total of 100 parts by mass with the monomer component), a recycled material of waste resin containing an impact-resistant reinforcing material for resin blending comprising a graft polymer having a mass average molecular weight of 40,000 to 200,000 ,
Waste polystyrene and / or waste impact-resistant polystyrene, or recycled polystyrene based on melt polystyrene of at least one kind of waste polystyrene and / or waste impact-resistant polystyrene and ABS mixed resin Resin composition. In claim 1, the reproduction styrenic resin composition wherein the monomer component in the resin compounding impact resistance reinforcing member, wherein 0.5 to 7.5 wt% including Mukoto a vinyl cyanide compound. In Claim 1 or 2 , the rubbery polymer in the impact-resistant reinforcing material for resin blending is polybutadiene, styrene / butadiene / α-olefin copolymer, ethylene / α-olefin non-conjugated diene copolymer, And one or more selected from the group consisting of acrylic rubber and a regenerated styrene resin composition. In any one of claims 1 to 3, regrind of the waste resin is composed of a hard polymer obtained by polymerizing a monomer component mainly comprising an aromatic vinyl compound containing no rubber polymer A regenerated styrenic resin composition comprising a modifier for resin blending . A regenerated styrene resin composition comprising the regenerated styrene resin resin composition according to any one of claims 1 to 4 and another thermoplastic resin blended and melt-mixed. A regenerated styrene resin molded article obtained by molding the regenerated styrene resin composition according to any one of claims 1 to 5 .