Resin composition containing plastic waste and film composed of the same

Abstract

To provide a resin composition which is used in a film that is formed by recycling a plastic waste and is excellent in molding stability, and a film composed of the same.SOLUTION: A resin composition contains, with respect to 100 pts.wt. of a plastic waste (A), 5 pts.wt. or more and 1,900 pts.wt. or less of polyethylene (B), and satisfies the following (1). (1) Melt tension (MS) at 190°C measured by a capillary viscometer is 30 mN or more.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a resin composition containing plastic waste and polyethylene, and a film made of the same. [Background technology]

[0002] Because plastic products are lightweight and inexpensive, they are used in a wide variety of applications, including as films, sheets, tubes, and other molded products, packaging materials, containers, daily necessities, agricultural materials, automotive parts, housings for electrical and electronic components, building materials, civil engineering materials, etc. With growing interest in environmental pollution issues in recent years, material recycling of these plastic products is being promoted.

[0003] In plastic material recycling, collected plastic waste is often melted and returned to raw material pellets, or recycled into consumable materials such as pallets.

[0004] At this time, it is likely that the moldability has been significantly reduced due to thermal oxidation degradation caused by molding processing before recycling, or photooxidation degradation caused by long-term use in harsh environments such as outdoors.

[0005] Furthermore, if different types of plastics are mixed in the collected plastic waste and recycled, the poor compatibility of each plastic causes the problem of the physical properties of the recycled plastic to deteriorate. In particular, multi-layer films and containers made of different types of plastics (hereinafter referred to as composite plastics) cannot be recycled because it is difficult to separate them by material, and so they are currently landfilled or incinerated.

[0006] In this context, additives that improve moldability have been investigated for recycling waste thermoplastic resin products by heating, melt molding, and so on.

[0007] For example, Patent Document 1 proposes a technique of adding polytetrafluoroethylene and alkyl (meth)acrylate polymers to waste polyolefin resin products as a melt tension improver. However, the method of Patent Document 1 involves adding a halogen-containing resin, which raises concerns about metal corrosion in the kneading and molding machines due to outgassing generated during the kneading or molding process.

[0008] Patent Document 2 proposes a technology for adding an alkyl methacrylate polymer having a specific mass average molecular weight to waste polyolefin resin products. However, in Patent Document 2, the only evaluation item for recycled products is the melt tension of the resin composition after repeated recycling, and the modification effect on molded products is not confirmed.

[0009] The addition of compatibilizers has also been investigated as a means of recycling composite plastics. Patent Document 3 examines the recycling of PE-PET and PP-ABS composite plastics using ionomer resins as compatibilizers, demonstrating that the addition of compatibilizers can improve the physical properties of composites of PE with PET or EVOH. While methods for modifying composite plastics into recycled resins with excellent physical properties have been investigated, as in this document, few products have been developed using recycled composite resins. Furthermore, our previous research has shown that, particularly in film molding, even when compatibilizers are used in recycled composite resins, low molding temperatures can result in the formation of fisheyes due to aggregates derived from PA or PET. On the other hand, increasing the molding temperature can also lead to the problem of poor film moldability. To promote widespread recycling, it is important to expand the applications of recycled resins, including composite plastics. [Prior art documents] [Patent documents]

[0010] [Patent Document 1] Japanese Patent Application Laid-Open No. 1999-060871 [Patent Document 2] Japanese Patent Application Laid-Open No. 2010-159322 [Patent Document 3] Japanese Patent Application Laid-Open No. 2001-220473 Summary of the Invention [Problem to be solved by the invention]

[0011] The present invention aims to provide a recycled film that is excellent in molding stability and film appearance, which is made from a resin composition that contains plastic waste and polyethylene and has high melt tension. [Means for solving the problem]

[0012] As a result of extensive research aimed at solving the above problems, the present inventors have found that a resin composition with a specific blending ratio is excellent in molding stability and film appearance, and have thus completed the present invention.

[0013] That is, the respective aspects of the present invention are the following [1] to []. [1] A resin composition containing 5 to 1,900 parts by weight of polyethylene (B) per 100 parts by weight of plastic waste (A), and satisfying the following (1): (1) The melt tension (MS) at 190°C measured with a capillary viscometer is 30 mN or more. [2] The resin composition according to [1], wherein the plastic waste (A) is composed of two or more thermoplastic resin components, contains at least a polyolefin, and contains, as other components, one or more resins selected from the group consisting of polyesters, polyamides, and ethylene-vinyl alcohol copolymers. [3] The resin composition according to [1] or [2], wherein the polyethylene (B) has a melt tension (MS) at 190°C measured with a capillary viscometer of 50 mN or more and 250 mN or less. [4] The resin composition according to any one of [1] to [3], wherein the polyethylene (B) is a high-pressure low-density polyethylene. [5] The resin composition according to any one of [1] to [4], further comprising a compatibilizer (C). [6] The resin composition according to [5], wherein the compatibilizer (C) is one or more resins selected from the group consisting of ethylene-vinyl acetate copolymer, maleic anhydride-modified polyethylene, and ethylene-glycidyl methacrylate copolymer. [7] A film made of the resin composition according to any one of [1] to [6]. [8] A method for producing a film, comprising molding a resin composition that contains 5 to 1,900 parts by weight of polyethylene (B) per 100 parts by weight of plastic waste (A) and satisfies the following (1) at 190°C to 300°C. (1) The melt tension (MS) at 190°C measured with a capillary viscometer is 30 mN or more. [9] The method for producing a film according to [8], wherein the film is formed by inflation molding. [Effects of the Invention]

[0014] A film made of the resin composition according to one embodiment of the present invention has few fisheyes and has excellent film appearance, and is useful for molded articles that require these physical properties. DETAILED DESCRIPTION OF THE INVENTION

[0015] The present invention will be described in detail below.

[0016] A resin composition according to one embodiment of the present invention contains 5 to 1900 parts by weight of polyethylene (B) per 100 parts by weight of plastic waste (A), and satisfies the following (1):

[0017] The plastic waste (A) is not particularly limited, but examples thereof include factory waste such as trimming waste and non-standard products generated in film factories, and waste films such as food packaging and daily necessities packaging discarded by consumers, or a mixture of these. The layer structure of the film may be a single-layer film or a multi-layer film, or a mixture of these. The shape of the film is not particularly limited, but examples thereof include films, bottles, cups, trays, tubes, etc.

[0018] Examples of resins contained in the plastic waste (A) include thermoplastic resins such as polyolefin, polyamide, ethylene-vinyl alcohol copolymer, polyester, and polystyrene.

[0019] Examples of polyolefins include high density polyethylene, low density polyethylene, linear low density polyethylene, polypropylene, ethylene-propylene copolymer, ethylene-acrylate copolymer, and ethylene-methacrylate copolymer.

[0020] Examples of polyamides include nylon 6, nylon 6,6, nylon 11, and nylon 12.

[0021] Examples of polyester include polyethylene terephthalate, glycol-modified polyethylene terephthalate (PETG resin), polybutylene terephthalate, and polylactic acid.

[0022] Among these, the resin contained in the plastic waste (A) preferably contains at least polyolefin, which has excellent film formability, and the other resin is preferably at least one member selected from the group consisting of polyester, polyamide, and ethylene-vinyl alcohol copolymer, with polyethylene terephthalate being the polyester and nylon 6 being the polyamide.

[0023] Of the resins contained in the plastic waste (A), it is preferable that the component with the largest proportion is polyolefin, as this has excellent film formability, and the proportion of polyolefin in the plastic waste (A) is preferably 70% by weight or more and 99% by weight or less, and other components are preferably 1% by weight or more and 30% by weight or less.

[0024] The melt mass flow rate (MFR) of the plastic waste (A) measured under conditions of 190°C and a load of 2.16 kg is preferably in the range of 0.1 to 20 g / 10 min, more preferably 0.1 to 10 g / 10 min, and even more preferably 0.2 to 7.0 g / 10 min. When the MFR is 0.1 g / 10 min or more, the mechanical load during extrusion of the resin composition is small, and when the MFR is 20 g / 10 min or less, the melt tension is high, resulting in excellent stability during film formation.

[0025] The melt tension (MS) of the polyethylene (B) constituting the present invention at 190°C is 50 mN or more and 250 mN or less. If MS is 50 mN or more, the stability of the portion where the molten resin is expanded with air (hereinafter referred to as a bubble) during inflation molding of the resin composition constituting the present invention is good, and if MS is 250 mN or less, the resin composition constituting the present invention has good stretchability and excellent film-forming properties at high speed.

[0026] Examples of the polyethylene (B) include ethylene homopolymers and copolymers of ethylene and α-olefins having 3 to 12 carbon atoms (ethylene-α-olefin copolymers). Examples include ethylene-based polymers such as low-density polyethylene, high-density polyethylene, ethylene-1-butene copolymer, ethylene-1-hexene copolymer, ethylene-1-octene copolymer, and ethylene-4-methyl-1-pentene copolymer. These ethylene-based polymers may be used alone or in combination of two or more. Among these ethylene-based polymers, low-density polyethylene, high-density polyethylene, ethylene-1-butene copolymer, ethylene-1-hexene copolymer, and ethylene-1-octene copolymer are preferred due to their excellent film formability and cost performance, and low-density polyethylene is particularly preferred due to its high bubble stability.

[0027] The method for producing such polyethylene (B) is not particularly limited, and examples thereof include high-pressure radical polymerization and high-, medium-, or low-pressure ionic polymerization using a Ziegler-Natta catalyst, a Phillips catalyst, or a metallocene catalyst, and such resins can be conveniently selected from commercially available products, such as those available from Tosoh Corporation under the trade names Petrothene (registered trademark), Nipolon Hard (registered trademark), Nipolon (registered trademark)-L, and Nipolon (registered trademark)-Z. The melt mass flow rate (MFR) of the polyethylene (B) measured at 190°C under a load of 2.16 kg is preferably in the range of 0.1 to 20 g / 10 min, more preferably 0.1 to 10 g / 10 min, and even more preferably 0.2 to 7.0 g / 10 min. When the MFR is 0.1 g / 10 min or more, the mechanical load during extrusion of the resin composition is small, and when the MFR is 20 g / 10 min or less, the melt tension is high, resulting in excellent stability during film formation.

[0028] The mixing ratio of the plastic waste (A) and polyethylene (B) constituting the present invention is such that the polyethylene (B) is contained in an amount of 5 to 1900 parts by weight per 100 parts by weight of the plastic waste (A), preferably 10 to 100 parts by weight, and more preferably 10 to 40 parts by weight.

[0029] When the polyethylene (B) is 5 parts by weight or more, the effect of improving molding stability is excellent, and when it is 95 parts by weight or less, the proportion of plastic waste (A) is high, resulting in excellent recyclability.

[0030] When the plastic waste (A) is made up of two or more types of thermoplastic resins, it is desirable to add a compatibilizer (C).

[0031] Examples of the compatibilizer (C) include ethylene-vinyl acetate copolymer, acid-modified polyolefin, ethylene-glycidyl methacrylate copolymer, ionomer resin, and oxazoline group-containing resin.

[0032] Specific examples of acid-modified polyolefins include maleic anhydride-modified polyethylene, maleic anhydride-modified polypropylene, maleic anhydride-modified ethylene-propylene (block or random) copolymer, maleic anhydride-modified ethylene-ethyl acrylate copolymer, and maleic anhydride-modified ethylene-vinyl acetate copolymer.

[0033] Among these, ethylene-vinyl acetate copolymer, maleic anhydride modified polyethylene, and ethylene-glycidyl methacrylate copolymer are preferred because of their excellent film formability into recycled resin films, and ethylene-vinyl acetate copolymer is more preferred because of its excellent film appearance.

[0034] The ethylene-vinyl acetate copolymer of the compatibilizer (C) may be an ethylene-vinyl acetate copolymer composition containing multiple ethylene-vinyl acetate copolymers with different vinyl acetate contents. In this case, from the viewpoint of compatibility, the types of ethylene-vinyl acetate copolymers are preferably three or more, and the difference in vinyl acetate content between the ethylene-vinyl acetate copolymers is preferably 40% by weight or less, and further preferably the difference in vinyl acetate content between at least one pair of ethylene-vinyl acetate copolymers is 5% by weight or more.

[0035] The melt mass flow rate (MFR) of the compatibilizer (C), measured at 190°C under a load of 2.16 kg, is preferably in the range of 0.1 to 20 g / 10 min, more preferably 0.1 to 10 g / 10 min, and even more preferably 0.2 to 7.0 g / 10 min. An MFR of 0.1 g / 10 min or more is preferred because the mechanical load during extrusion of the resin composition is small. An MFR of 20 g / 10 min or less results in high melt tension and excellent stability during film formation.

[0036] The compatibilizer (C) is preferably added in an amount of 1 part by weight to 30 parts by weight, more preferably 1 part by weight to 20 parts by weight, and even more preferably 1 part by weight to 10 parts by weight, per 100 parts by weight of the plastic waste (A), which can improve the appearance of the obtained film.

[0037] The resin composition according to one embodiment of the present invention has a melt tension (MS) of 30 mN or more at 190°C as measured with a capillary viscometer. When the MS is 30 mN or more, bubble stability during inflation molding is good, and a uniform film can be obtained. While there is no upper limit for the MS, a value of 250 mN or less is preferred, as this provides good stretchability and enables high-speed film formation.

[0038] In the method for producing a resin composition, when the compatibilizer (C) is added to the plastic waste (A), it is preferable to mix them using a device such as a Henschel mixer, a V blender, a ribbon blender, or a tumbler, and then melt-knead and granulate them using a single-screw extruder, a twin-screw extruder, a multi-screw extruder, a Banbury mixer, a pressure kneader, a rotating roll, or an internal mixer, among which a twin-screw extruder is preferred because of its excellent dispersibility and continuous productivity.

[0039] When kneading is performed using a twin-screw extruder, the screw rotation speed is not particularly limited, but is preferably 50 rpm or more and 3000 rpm or less, and more preferably 150 rpm or more and 1000 rpm or less. A screw rotation speed of 50 rpm or more is preferred because the dispersibility of the mixed components is improved and the resulting resin has excellent physical properties, while a screw rotation speed of 3000 rpm or less is preferred because the resin does not deteriorate due to excessive shear heat generation and the resulting resin has excellent physical properties.

[0040] The kneading temperature is preferably from the melting point of the component with the lowest melting point among the plastic waste (A) and the compatibilizer (C), or from the glass transition temperature to about 300°C in the case of an amorphous resin.

[0041] The polyethylene (B) may be compounded by mixing it with the plastic waste (A) and, if necessary, the compatibilizer (C) using equipment such as a Henschel mixer, V blender, ribbon blender, or tumbler, followed by melt-kneading in a heated kneading device such as a single-screw extruder, twin-screw extruder, multi-screw extruder, Banbury mixer, pressure kneader, rotating roll, or internal mixer; or by dry blending or blending with the plastic waste (A) alone or with a resin obtained by melt-kneading the plastic waste (A) and the compatibilizer (C) using an autofeeder during film molding without prior melt-kneading.

[0042] The resin composition may further contain an antistatic agent, a light stabilizer, an ultraviolet absorber, a nucleating agent, an antioxidant, an antiblocking agent, a flow improver, a mold release agent, a flame retardant, a colorant, an inorganic neutralizing agent, a hydrochloric acid absorber, a filler conductive agent, a chain extender, a hydrolysis inhibitor, or the like, as long as the effects of the present invention are not impaired.

[0043] The film according to one embodiment of the present invention is made from the above resin composition.

[0044] The film molding method is not particularly limited, and examples include inflation molding, coextrusion inflation molding, T-die molding, coextrusion T-die molding, calendar molding, and compression molding. Among these, inflation molding, coextrusion inflation molding, T-die molding, and coextrusion T-die molding are preferred due to their excellent productivity, with inflation molding and coextrusion inflation molding being more preferred. The inflation molding method is not particularly limited, and conventionally known methods can be used. From the viewpoint of stable molding process, the molding temperature is preferably 190 to 300°C, more preferably 200 to 270°C. Furthermore, the blow-up ratio is preferably 1.2 to 6.0. A blow-up ratio of 1.2 or higher results in good impact resistance of the film, while a blow-up ratio of 6.0 or lower results in less bubble sway during inflation molding, resulting in stable film with fewer wrinkles. The molding speed is preferably 5 to 120 m / min to minimize bubble meandering during molding.

[0045] The thickness of the film is preferably 5 to 150 μm, more preferably 5 to 100 μm, and even more preferably 5 to 50 μm. When the thickness is 5 μm or more, the film is less likely to break due to gel during molding, which is good. When the thickness is 150 μm or less, the film is not too hard, so that misalignment during winding is less likely to occur, and the appearance of the wound film is good.

[0046] The film may be a single layer or may be used in the form of a multilayer film. The layer structure of the multilayer film is not particularly limited, but may include, for example, not only the resin composition (I) layer but also layers composed of other components, such as a virgin resin layer (II), an adhesive layer (III), or a barrier layer (IV). Specific examples include (I) / (II), (II) / (I) / (II), (I) / (III) / (IV) / (III) / (I), and (I) / (III) / (IV) / (III) / (II).

[0047] The above films are useful as packaging films for food, daily necessities, industrial parts, pharmaceuticals, office supplies, chemical supplies, etc., surface protection films, agricultural films such as silage wrap, shrink films, transport bags, shopping bags, etc. [Example]

[0048] EXAMPLES The present invention will be described below with reference to examples and comparative examples, but the present invention is not limited to these. (1) Melt mass flow rate (MFR) The plastic waste, polyethylene (PE), and compatibilizer were measured using a melt indexer (manufactured by Takara Industries) at 190°C and a load of 2.16 kg. (2) Vinyl acetate content The vinyl acetate content was measured in accordance with JIS K6924-1. (3) Melt tension (MS) For the plastic waste, PE, compatibilizer, and resin composition, a capillary rheometer (manufactured by Toyo Seiki Seisakusho) was used. The resin was heated to 190°C inside the device and extruded into the atmosphere at 23°C at a rate of 10 mm / min from a nozzle with a diameter of 2.095 mm and a length of 8.0 mm to form a strand, and the tension was measured when this strand was taken up at a rate of 10 m / min. (4) Number of fisheyes (FE) 1m of inflation film 2 The number of FEs per unit area was visually counted. [Example 1] The plastic waste (A) was a multilayer film process waste (A1) generated by a laminate film manufacturer, containing 75 parts by weight of polyethylene (PE) and 25 parts by weight of nylon 6 (PA6). This plastic waste (A) was crushed with a rotary cutter and 100 parts by weight was used. PE (B) was virgin high-pressure low-density polyethylene (B1) (manufactured by Tosoh Corporation, trade name Petrothene® 250R, density 924 kg / m). 3 25 parts by weight of plastic waste (A) (MFR 2.0 g / 10 min, MS 90 mN) was used, and these were dry-blended in a tumbler mixer, and then melt-kneaded at 250°C using a twin-screw extruder to obtain a resin composition. The MS of the obtained resin composition was 34 mN. The MFR and MS of plastic waste (A) were measured by using 100 parts by weight of plastic waste (A) crushed with a rotary cutter and melt-kneaded at 250°C using a twin-screw extruder to prepare pellets of plastic waste (A). The MFR and MS were found to be 1.5 g / 10 min and 20 mN.

[0049] The above resin composition was fed into an inflation molding machine (manufactured by Placo Co., Ltd., screw diameter 50 mmφ) and formed into an inflation film under the conditions of a temperature of 200°C, a blow-up ratio of 2.5, a take-up speed of 10 m / min, and a film thickness of 40 μm.

[0050] The number of FEs generated in the obtained inflation film was measured by the above-mentioned evaluation method. The evaluation results are shown in Table 1. [Example 2] As the compatibilizer (C), an ethylene-vinyl acetate copolymer composition (C1) having the following composition was used.

[0051] 50% by weight of ethylene-vinyl acetate copolymer (manufactured by Tosoh Corporation, trade name Ultrathene (registered trademark) 640) with a vinyl acetate content of 25% by weight and a MFR of 3.0 g / 10 min 25% by weight of an ethylene-vinyl acetate copolymer (manufactured by LANXESS AG, trade name Levaprene (registered trademark) 500) with a vinyl acetate content of 50% by weight and a MFR of 3.0 g / 10 min 25% by weight of an ethylene-vinyl acetate copolymer (manufactured by LANXESS AG, trade name Levaprene (registered trademark) 800) with a vinyl acetate content of 80% by weight and a MFR of 5.0 g / 10 min The ethylene-vinyl acetate copolymer composition (C1) was melt-kneaded once in a twin-screw extruder at 160°C and pelletized before use. The MFR of the resulting compatibilizer pellets was 10 g / 10 min. Five parts by weight of this ethylene-vinyl acetate copolymer composition (C1), 100 parts by weight of waste plastic (A) from a multilayer film process containing 75 parts by weight of PE and 25 parts by weight of PA6 generated by a laminate film manufacturer (A1) crushed with a rotary cutter, and 25 parts by weight of virgin high-pressure low-density polyethylene (B1) as PE (B) were used. These were dry-blended in a tumbler mixer and then melt-kneaded in a twin-screw extruder at 250°C to obtain resin composition pellets. The MS of the resulting resin composition was 33 mN.

[0052] The resin composition was blown into an inflation film in the same manner as in Example 1.

[0053] The number of FEs generated in the obtained inflation film was measured by the above-mentioned evaluation method. The evaluation results are shown in Table 1. [Example 3] An inflation film was obtained in the same manner as in Example 1, except that the plastic waste (A) used was a multilayer film process waste (A2) containing 75 parts by weight of PE and 25 parts by weight of polyethylene terephthalate (PET) generated by a laminate film manufacturer. The MFR of the pellets made from the obtained plastic waste (A) was 1 g / 10 min, the MS was 21 mN, and the MS of the resin composition was 35 mN.

[0054] The number of FEs generated in the obtained inflation film was measured by the above-mentioned evaluation method. The evaluation results are shown in Table 1. [Example 4] An inflation film was obtained in the same manner as in Example 2, except that the plastic waste (A) used was a multilayer film process waste (A2) containing 75 parts by weight of PE and 25 parts by weight of PET generated by a laminate film manufacturer. The MS of the obtained resin composition was 34 mN.

[0055] The number of FEs generated in the obtained inflation film was measured by the above-mentioned evaluation method. The evaluation results are shown in Table 1. [Example 5] An inflation film was obtained in the same manner as in Example 1, except that the inflation film molding temperature was 240°C.

[0056] The number of FEs generated in the obtained inflation film was measured by the above-mentioned evaluation method. The evaluation results are shown in Table 1. [Example 6] An inflation film was obtained in the same manner as in Example 2, except that the inflation film molding temperature was 240°C.

[0057] The number of FEs generated in the obtained inflation film was measured by the above-mentioned evaluation method. The evaluation results are shown in Table 1. [Example 7] An inflation film was obtained in the same manner as in Example 4, except that the inflation film molding temperature was 240°C.

[0058] The number of FEs generated in the obtained inflation film was measured by the above-mentioned evaluation method. The evaluation results are shown in Table 1. [Example 8] PE (B) was virgin high-pressure low-density polyethylene (B2) (manufactured by Tosoh Corporation, trade name Petrothene (registered trademark) 360, density 919 kg / m 3 An inflation film was obtained in the same manner as in Example 7, except that 25 parts by weight of a resin composition (polymerizable copolymer, MFR 1.6 g / 10 min, MS 220 mN) was used. The MS of the resulting resin composition was 58 mN.

[0059] The number of FEs generated in the obtained inflation film was measured by the above-mentioned evaluation method. The evaluation results are shown in Table 1. [Example 9] An inflation film was obtained in the same manner as in Example 8, except that maleic anhydride-modified polyethylene (C2) with an MFR of 3 g / 10 min (manufactured by SK Geo Centric Japan Co., Ltd., product name OREVAC (registered trademark) OE825) was used as the compatibilizer (C). The MS of the obtained resin composition was 62 mN.

[0060] The number of FEs generated in the obtained inflation film was measured by the above-mentioned evaluation method. The evaluation results are shown in Table 1. [Example 10] An inflation film was obtained in the same manner as in Example 8, except that an ethylene-vinyl acetate copolymer (C3) (manufactured by Tosoh Corporation, trade name Ultrathene (registered trademark) 640) having a vinyl acetate content of 25 wt % and an MFR of 3.0 g / 10 min was used as the compatibilizer (C). The MS of the obtained resin composition was 61 mN.

[0061] The number of FEs generated in the obtained inflation film was measured by the above-mentioned evaluation method. The evaluation results are shown in Table 1. [Example 11] An inflation film was obtained in the same manner as in Example 8, except that 75 parts by weight of PE generated by a laminate film manufacturer and 90 parts by weight of a multilayer film process waste (A2) containing 25 parts by weight of PET were used as plastic waste (A), and 11 parts by weight of virgin high-pressure low-density polyethylene (B2) was used as PE (B). The MS of the resin composition was 40 mN.

[0062] The number of FEs generated in the obtained inflation film was measured by the above-mentioned evaluation method. The evaluation results are shown in Table 1. [Comparative Example 1] An inflation film was obtained in the same manner as in Example 1, except that polyethylene (B) was not used.

[0063] The number of FEs generated in the obtained inflation film was measured by the above-mentioned evaluation method. The evaluation results are shown in Table 1. Comparative Example 2 An inflation film was obtained in the same manner as in Comparative Example 1, except that the inflation film molding temperature was 240°C.

[0064] The number of FEs generated in the obtained inflation film was measured by the above-mentioned evaluation method. The evaluation results are shown in Table 1. Comparative Example 3 As the compatibilizer (C), the ethylene-vinyl acetate copolymer composition (C1) used in Example 2 was used.

[0065] Five parts by weight of the ethylene-vinyl acetate copolymer composition (C1) and 100 parts by weight of the plastic waste (A) were milled with a rotary cutter from a multilayer film process waste (A1) containing 75 parts by weight of PE and 25 parts by weight of PA6 generated by a laminate film manufacturer. These were dry-blended in a tumbler mixer and then melt-kneaded at 250°C in a twin-screw extruder to obtain resin composition pellets. The MS of the resulting resin composition was 20 mN.

[0066] The resin composition was extruded in the same manner as in Comparative Example 2 to obtain an inflation film.

[0067] The number of FEs generated in the obtained inflation film was measured by the above-mentioned evaluation method. The evaluation results are shown in Table 1. Comparative Example 4 An inflation film was obtained in the same manner as in Comparative Example 3, except that 100 parts by weight of a multilayer film process waste (A2) containing 75 parts by weight of PE and 25 parts by weight of PET generated by a laminate film manufacturer was used as the plastic waste (A). The MS of the obtained resin composition was 21 mN.

[0068] The number of FEs generated in the obtained inflation film was measured by the above-mentioned evaluation method. The evaluation results are shown in Table 1. Comparative Example 5 An inflation film was obtained in the same manner as in Example 5, except that 75 parts by weight of PE generated by a laminate film manufacturer and 100 parts by weight of a multilayer film process waste (A2) containing 25 parts by weight of PET were used as plastic waste (A), and 11 parts by weight of virgin high-pressure low-density polyethylene (B1) was used as PE (B). The MS of the obtained resin composition was 28 mN.

[0069] The number of FEs generated in the obtained inflation film was measured by the above-mentioned evaluation method. The evaluation results are shown in Table 1. Comparative Example 6 As plastic waste (A), 75 parts by weight of PE generated by a laminate film manufacturer and 100 parts by weight of process loss of a multilayer film (A2) containing 25 parts by weight of PET were used. As PE (B), virgin high-pressure low-density polyethylene (B3) (manufactured by Tosoh, trade name Petrothene (registered trademark) 203, density 919 kg / m 3 An inflation film was obtained in the same manner as in Comparative Example 5, except that 25 parts by weight of a resin composition (polymerizable copolymer, MFR 8.0 g / 10 min, MS 26 mN) was used. The MS of the resulting resin composition was 22 mN.

[0070] The number of FEs generated in the obtained inflation film was measured by the above-mentioned evaluation method. The evaluation results are shown in Table 1. Comparative Example 7 An inflation film was obtained in the same manner as in Comparative Example 5, except that 75 parts by weight of PE generated by a laminate film manufacturer and 100 parts by weight of a multilayer film process waste (A2) containing 25 parts by weight of PET were used as plastic waste (A), and 150 parts by weight of virgin high-pressure low-density polyethylene (B3) was used as PE (B). The MS of the obtained resin composition was 24 mN.

[0071] The number of FEs generated in the obtained inflation film was measured by the above-mentioned evaluation method. The evaluation results are shown in Table 1.

[0072] [Table 1] [Industrial Applicability]

[0073] Films made from the resin composition of the present invention are useful as packaging films for foods, daily necessities, industrial parts, pharmaceuticals, office supplies, chemical supplies, etc., surface protection films, agricultural films such as silage wrap, shrink films, transport bags, shopping bags, etc.

Claims

1. A resin composition comprising 5 parts by weight or more and 1,900 parts by weight or less of polyethylene (B) per 100 parts by weight of plastic waste (A), and satisfying the following (1): (1) The melt tension (MS) at 190°C measured with a capillary viscometer is 30 mN or more.

2. The resin composition according to claim 1, wherein the plastic waste (A) is composed of two or more thermoplastic resin components, contains at least a polyolefin, and contains, as other components, one or more resins selected from the group consisting of polyesters, polyamides, and ethylene-vinyl alcohol copolymers.

3. 2. The resin composition according to claim 1, wherein the polyethylene (B) has a melt tension (MS) at 190°C measured with a capillary viscometer of 50 mN or more and 250 mN or less.

4. The resin composition according to claim 1, wherein the polyethylene (B) is a high-pressure low-density polyethylene.

5. The resin composition according to claim 1 , further comprising a compatibilizer (C).

6. The resin composition according to claim 5, wherein the compatibilizer (C) is one or more resins selected from the group consisting of ethylene-vinyl acetate copolymer, maleic anhydride-modified polyethylene, and ethylene-glycidyl methacrylate copolymer.

7. A film made of the resin composition according to any one of claims 1 to 6.

8. A method for producing a film, comprising molding a resin composition that contains 5 parts by weight or more and 1,900 parts by weight or less of polyethylene (B) per 100 parts by weight of plastic waste (A) and satisfies the following (1) at 190°C or more and 300°C or less into a film. (1) The melt tension (MS) at 190°C measured with a capillary viscometer is 30 mN or more.

9. The method for producing a film according to claim 8, wherein the film is formed by inflation molding.

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