JP2007138137A - Composite material and its molded product - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a composite material mainly containing a material obtained by container package recycling as a new application for material obtained by container package recycling, and its molded product. <P>SOLUTION: The composite material comprises a material obtained by container package recycling and composed of a thermoplastic resin and inorganic powder and/or wooden material. Preferable inorganic powder is fly ash. Preferable material obtained by container package recycling is composed of at least 20 wt.% polypropylene, 30-70 wt.% polyethylene and 3-30 wt.% polystyrene. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a composite material mainly composed of a container packaging recycling material and a molded body thereof.

  The plastic waste collected by the local government is a mixture containing a polyolefin resin, a thermoplastic resin such as PET or polystyrene, and an inorganic substance (metals), and an effective recycling method is desired. In particular, it is desired to develop a new application of a container and packaging recycling material obtained from recovered plastic waste and excluding PET.

  However, the container and packaging recycle material is usually inhomogeneous, and there are several difficulties in using it at the industrial level.

  The present invention has been devised to overcome the above-described difficulties, and an object of the present invention is to provide a composite material mainly composed of a container packaging recycling material and a molded body thereof as a new use of the container packaging recycling material.

  The invention according to claim 1 is a composite material characterized by containing a container and packaging recycling material made of a thermoplastic resin and an inorganic powder.

  The invention according to claim 2 is the composite material according to claim 1, wherein the inorganic powder is fly ash.

  The invention according to claim 3 is a composite material characterized by containing a container / packaging recycle material made of a thermoplastic resin and a wood-based material.

  The invention according to claim 4 is characterized in that the container and packaging recycling material includes at least 20% by weight of polypropylene, 30 to 70% by weight of polyethylene, and 3 to 30% by weight of polystyrene. The composite material described in 1.

  The invention according to claim 5 is the composite material according to any one of claims 1 to 4, further comprising an unsaturated carboxylic acid-modified thermoplastic resin.

  The invention according to claim 6 is the composite material according to claim 5, wherein the unsaturated carboxylic acid-modified thermoplastic resin is maleic anhydride-modified polypropylene.

  The invention according to claim 7 is the composite material according to claim 5, wherein the unsaturated carboxylic acid-modified thermoplastic resin is maleic anhydride-modified polyethylene.

  The invention according to claim 8 is the composite material according to claim 5, wherein the unsaturated carboxylic acid-modified thermoplastic resin is a mixture of maleic anhydride-modified polypropylene and maleic anhydride-modified polyethylene.

  The invention according to claim 9 is the composite material according to any one of claims 1 to 8, further comprising a styrene-olefin copolymer.

  The invention according to claim 10 is the composite material according to claim 9, wherein the styrene-olefin copolymer is a styrene / ethylene / butylene / styrene copolymer.

  The invention which concerns on Claim 11 is a molded object which consists of a composite material in any one of Claims 1-10.

  In this invention, a container packaging recycling material is a mixture which is obtained from the plastic waste collect | recovered by the local government, and has thermoplastic resins, such as polyolefin resin, as a main component. However, recycled materials mainly composed of PET resin are excluded. The collected plastic waste is subjected to steps such as separation and washing, and is granulated or pelletized, and then sent to the molding step. In the separation step, PET, polystyrene, and inorganic substances (metals) are removed as much as possible to obtain a mixture containing a polyolefin resin as a main component. This is used as a container packaging recycling material. Usually, plastic waste that is washed and ground and floats on water is used. The container packaging recycle material is composed of, for example, 30 to 70% by weight of polyethylene, 20% by weight or more of polypropylene, preferably 60% by weight or less, and 3 to 30% by weight of polystyrene. Actually, the analysis results of 10 points were 40 to 60% by weight of polyethylene, 30 to 50% by weight of polypropylene, and 5 to 20% by weight of polystyrene. When polyethylene is decreased and polystyrene is increased, the impact strength of the molded product tends to be insufficient, and when polyethylene is increased and polystyrene is decreased, mechanical strength (particularly elastic modulus) tends to be insufficient.

  The shape of the container and packaging recycling material is not particularly limited, and a shape corresponding to the molding method is selected. When using a uniaxial melt kneader described later, the container and packaging recycle material may be a granulated product or a pulverized product of about 5 to 10 mm, which is advantageous in terms of cost and physical properties because it does not need to be heated and pelletized. It is.

  The inorganic powder used as the filler in the invention according to claim 1 may be an inorganic material generally filled in plastic, and examples thereof include fly ash, calcium carbonate, talc, and silica powder. Above all, fly ash is generated in large quantities in thermal power plants, etc., and is not sufficiently recycled, so it is inexpensive and the powder is fine spherical, so it is fluid when melted and mixed in resin. Is large, the filling amount can be increased, and it is preferably used.

  The proportion (weight) of the inorganic powder is preferably in the range of 20-80% in the total material.

  The wood-based material used as the filler in the invention according to claim 3 may be wood, bamboo pulverized or cut bodies. It is preferable that 50% or more of the wood-based material has an elongated shape such as a rod shape, a fiber shape, or a scale shape having an aspect ratio of 3 or more. If the aspect ratio is less than 3, the effect as a reinforcing material may be reduced. Moreover, the tree species of the woody material used is not particularly limited as long as it is a general-purpose architectural or structural woody material. For example, conifers such as cedar, cypress, spruce, fur, radiata pine, etc .; broadleaf trees such as birch, apiton, chamelere, sengonlaut, aspen, etc., but not only woody materials produced from these forests, Plant materials produced outside the forest, such as wolfberry, can also be used as woody materials. The form of the wood-based material is not particularly limited, but, for example, raw materials such as logs of wood-based material, thinned wood, scraps generated at factories and residential building sites, waste pallet materials discarded after transportation of materials, Arbitrary woody materials such as generated demolition waste materials and waste materials such as distribution packing materials can be used as a material in combination of one or several kinds. The woody material is in the range of 30 to 80% by weight in the total material. The mixing ratio (parts by weight) of the wood-based material and the thermoplastic resin is preferably 30:70 to 80:20, more preferably 40:60 to 70:30, and still more preferably 50:50 to 60:40. If the ratio of the wood-based material is more than 80% by weight, mutual dispersion becomes difficult at the time of molding, and the thermoplastic resin does not physically bond with the wood-based material, so that a nest can easily enter the molded product and the moldability deteriorates. Sometimes. Further, when the ratio of the wood-based material is less than 30% by weight, the thermoplastic resin is completely filled in the pores such as the temporary conduit of the wood-based material, and the porous characteristic of the wood-based material is lost. The feel of the molded product may be poor and it may be difficult to obtain a sufficient wood texture. Therefore, the mixing ratio is preferably within the above range. The unsaturated carboxylic acid-modified thermoplastic resin used as an optional additional component in the invention according to claim 5 is maleic anhydride modified polypropylene (hereinafter abbreviated as MAPP), maleic anhydride modified polyethylene (hereinafter abbreviated as MAPE). Etc. MAPP is suitable for reinforcing the interface between the filler and the thermoplastic resin, and exhibits a great effect particularly when the amount of polypropylene in the thermoplastic resin is large.

  MAPP can be prepared, for example, by the method described in Japanese Patent No. 3462808. In this case, the degree of acid modification of polypropylene by maleic anhydride is preferably 1% to 15%. If the acid modification degree is 1% or less, a sufficient interface reinforcing effect may not be obtained. If the acid modification degree is 15% or more, a remarkable effect may not be obtained. When MAPP is used as an optional additive component, the appropriate amount of addition varies depending on the type of filler. When an inorganic powder such as fly ash is used as the filler, the amount of MAPP added is preferably 0.1 parts by weight or more, more preferably 0.00 parts by weight with respect to a total of 100 parts by weight of the thermoplastic resin and the inorganic powder. 3 parts by weight or more, preferably 5 parts by weight or less, more preferably 3 parts by weight or less. If the amount of MAPP added is small, the effect of improving the adhesion between the thermoplastic resin and the inorganic powder by MAPP may not be sufficiently exhibited. Moreover, even if it adds in large quantities, the remarkable improvement effect with respect to cost may not be acquired. When a wood material is used as the filler, the amount of MAPP added is preferably 2 parts by weight or more, more preferably 3 parts by weight or more, with respect to 100 parts by weight in total of the thermoplastic resin and the wood material. Is 5 parts by weight or less, more preferably 4 parts by weight or less. If the amount of MAPP added is small, the effect of improving the adhesion between the thermoplastic resin and the wood-based material by MAPP may not be sufficiently exhibited. Even if it is added in a large amount, a remarkable improvement effect may not be obtained.

  In addition, as described above, when the amount of polyethylene in the container and packaging recycling material is large, the elastic modulus tends to be insufficient. In such a case, MAPE exhibits a great effect. In this case, the degree of polyethylene modification with maleic anhydride is preferably 1% to 15%. If it is 1% or less, a sufficient interface reinforcing effect may not be obtained, and if it is 15% or more, a remarkable effect may not be obtained on cost. The addition amount of MAPE is preferably 0.1 parts by weight or more, more preferably 0.3 parts by weight or more, preferably 5 parts by weight or less, with respect to 100 parts by weight of the total of the thermoplastic resin and the inorganic powder. More preferably, it is 3 parts by weight or less. If the amount of MAPE added is small, the effect of improving the adhesion between the thermoplastic resin and the inorganic powder by MAPE may not be sufficiently exhibited. Moreover, even if it adds in large quantities, the remarkable improvement effect with respect to cost may not be acquired. When a wood material is used as the filler, the MAPE addition amount is preferably 2 parts by weight or more, more preferably 3 parts by weight or more, preferably 100 parts by weight or more in total of the thermoplastic resin and the wood material. 5 parts by weight or less, more preferably 4 parts by weight or less. If the amount of MAPE added is small, the effect of improving the adhesion between the thermoplastic resin and the wood-based material by MAPE may not be sufficiently exhibited. Even if it is added in a large amount, a remarkable improvement effect may not be obtained.

  Since the container and packaging recycle material contains both polypropylene and polyethylene, when MAPP and MAPE are added together in the above proportion, the maximum improvement effect can be obtained with a small amount.

  Actually, the amount of MAPP and MAPE used is the minimum amount necessary for the interface reinforcement between fly ash and thermoplastic resin, and the reinforcement of the polyolefin / polystyrene interface contained in the container packaging recycling material is performed using SEBS, which will be described later. Is the most efficient in terms of cost effectiveness.

  The styrene-olefin copolymer used as an optional additional component in the invention according to claim 9 is styrene / ethylene / butylene / styrene copolymer (hereinafter abbreviated as SEBS), styrene / butylene / styrene copolymer (SBS). And styrene / butadiene / butylene / styrene copolymer (SBBS). The styrene-olefin copolymer improves the compatibility between the polyolefin resin as the main component contained in the container packaging recycling material and the polystyrene resin contained in a small amount, thereby improving the physical properties. In particular, SEBS is suitable for improving the physical properties of containers and packaging recycling materials.

  The addition amount of the styrene-olefin copolymer is preferably 0.1 parts by weight or more, more preferably 0.3 parts by weight or more, preferably 100 parts by weight or more based on the total amount of the thermoplastic resin and the filler. 5 parts by weight or less, more preferably 3 parts by weight or less. If the amount added is too small, the effect of improving the adhesion between the polyolefin resin and the polystyrene resin due to the addition of the styrene-olefin copolymer may not be sufficiently exhibited. Moreover, even if this is added in a large amount, a significant improvement effect on the cost may not be obtained.

  In the invention according to claim 11, as a method for molding a composite material according to the present invention, general injection molding, extrusion molding, or the like may be used. And since it is not constant, the method of pressing this melt after melt-mixing a thermoplastic resin and a filler is suitable. In the injection molding that keeps the molten state for a long time with respect to the material variation, the generation of gas or the like may be a problem. On the other hand, in the extrusion molding, the surface property may be deteriorated due to a change in the melt viscosity or the like. The melt mixer is not particularly limited as long as it is an apparatus that forms a molten mixture obtained by melting a thermoplastic resin and mixing a filler. For example, a method using a general extrusion apparatus, or a rotating shaft inserted into a melt mixing chamber is provided with a plurality of stirring blades for melting thermoplastic resin by frictional heat and mixed in the preceding process. A melt mixer (for example, “K-mixing machine manufactured by Kohan Co., Ltd.”) is obtained by feeding the filler and resin into the chamber and rotating the stirring blade to obtain a molten mixture in which the filler is mixed with the molten thermoplastic resin. "(Trade name)). In this method of using a wood material as a filler in the melt mixer, the wood material and the thermoplastic resin are melt-mixed without any pretreatment such as preliminary drying, and without making the wood material a fine powder. can do. In addition, in the method using a container and packaging recycle material in this melt mixer, an unspecified multi-component thermoplastic resin can be melt-mixed relatively uniformly.

  According to the present invention, this mixture can be used for a new use as a molding material by adding inorganic powder or woody material as a filler to a container and packaging recycle material obtained from recovered plastic waste.

  Further, by adding an unsaturated carboxylic acid-modified thermoplastic resin and / or a styrene-olefin copolymer, the physical properties of the molded article can be stabilized, particularly impact resistance.

  As described above, the present invention has significant significance in terms of cost and society by handling heterogeneous recycled resin.

  Next, in order to specifically explain the present invention, examples of the present invention and comparative examples for showing comparison with the examples will be given.

Example 1
As a thermoplastic resin, 105 g of the obtained container and packaging recycling material made of plastic waste collected by the local government and 195 g of fly ash (made by Hokuriku Electric Power Company) as a filler are melt-kneaded ("K-mixing machine" manufactured by Kohan). (Trade name)).

The obtained massive melt-kneaded product was pressurized with 50 kg / cm 2 while being cooled using a cooling press device to obtain a square plate-shaped molded product having a side of 200 mm.

  The component analysis of the container packaging recycling material was performed by the following method.

  The container packaging recycle material used as the thermoplastic resin was melt-kneaded in the same manner as described above without including the filler, and pressed to obtain a plate molded body. From the surface reflection infrared spectrum analysis of this plate, it was confirmed that the main components were polyethylene, polypropylene and polystyrene. In addition, standard samples of polyethylene, polypropylene, and polystyrene were melted and pressed to produce standard plates, and the content of each component was calculated from the absorption spectrum intensity ratio between the plate obtained from the container packaging recycling material and the standard plate. . This value is shown in the table below.

Example 2
A plate-shaped molded product was obtained in the same manner as in Example 1 except that 60 g of a wood-based material (sawmill waste (planar waste whitewood) generated at a sawmill) was used instead of fly ash.

Examples 3-8
MAPP (Uyox 1010 (trade name) manufactured by Sanyo Kasei Co., Ltd.) and / or MAPE (Umex 2000 manufactured by Sanyo Kasei Co., Ltd.) as a thermoplastic resin modified with an unsaturated carboxylic acid which is an optional additive component in the thermoplastic resin and filler. Name)) and / or SEBS (Tuftec H1052 (trade name) manufactured by Asahi Kasei Chemicals Corporation) was added as a styrene-olefin copolymer, and the other processes were performed in the same manner as in Example 1 to obtain a plate-shaped molded product.

Example 9
A plate-like molded product was obtained in the same manner as in Example 1 except that fly ash and a wood-based material were used in combination as fillers.

Comparative Examples 1-3
A plate-like molded product was obtained in the same manner as in Example 1 except that no filler was used.

Performance evaluation test A test piece was cut out from each plate obtained in Examples 1 to 15 and Comparative Examples 1 to 3, and a tensile test and an Izod impact test were performed. The obtained tensile modulus and impact value are shown in Tables 1 to 3.

  In the table, PE is polyethylene, PP is polypropylene, PSt is polystyrene, MAPP is maleic anhydride-modified polypropylene, MAPE is maleic anhydride-modified polyethylene, and SEBS is styrene / ethylene / butylene / styrene copolymer.

  Since Example 1 uses fly ash as a filler as compared with Comparative Example 1, it achieves a high tensile elastic modulus and impact value. The present invention provides a composite material that can produce a molded article that can withstand practical use by using a filler in combination with a resin having low physical properties as compared with a general industrial resin material as shown in Comparative Example 1. Can do.

  In Example 2, compared with Comparative Example 3, the same physical properties are realized using wood flour.

  Compared to Example 1 by adding MAPP as an optional additive component in Example 3, adding MAPE as an optional additive component in Example 4, and adding SEBS as an optional additive component in Example 5. Therefore, higher physical properties are expressed. Even when the addition amounts of these additive components are the same, when these are used in combination as in Examples 6 to 8, even higher effects are exhibited.

  In Examples 10 to 11, the amount of polypropylene and polystyrene is less than the range specified in claim 4, and the mechanical properties of the thermoplastic resin itself are low (Comparative Example 2). High physical properties are ensured by blending MAPP, MAPE and SEBS as additive components.

  In Example 12, since there was little polystyrene in the container packaging recycling material to be used, it implemented without adding the styrene-olefin copolymer as an arbitrary addition component.

  In Example 13, the container and packaging recycle material was sampled and used when the amount of polyethylene was the largest. By using the amount of MAPP and SEBS to the extent of this embodiment, it is possible to provide a high-quality molded article even when a container / packaging recycled material whose quality varies. Moreover, even if MAPP and MAPE are used to the extent of this example as in Example 14 using the same container and packaging recycle material, it is possible to efficiently improve the quality against variations in container and packaging PP and PE. It becomes.

In Example 15, fly ash and wood flour were used in combination as fillers.

Claims (11)

  A composite material comprising a container and packaging recycling material made of a thermoplastic resin and an inorganic powder.   The composite material according to claim 1, wherein the inorganic powder is fly ash.   A composite material comprising a container and packaging recycling material made of a thermoplastic resin and a wood-based material.   The composite material according to any one of claims 1 to 3, wherein the container and packaging recycle material contains at least 20% by weight of polypropylene, 30 to 70% by weight of polyethylene, and 3 to 30% by weight of polystyrene.   The composite material according to claim 1, further comprising an unsaturated carboxylic acid-modified thermoplastic resin.   6. The composite material according to claim 5, wherein the unsaturated carboxylic acid-modified thermoplastic resin is maleic anhydride-modified polypropylene.   6. The composite material according to claim 5, wherein the unsaturated carboxylic acid-modified thermoplastic resin is maleic anhydride-modified polyethylene.   6. The composite material according to claim 5, wherein the unsaturated carboxylic acid-modified thermoplastic resin is a mixture of maleic anhydride-modified polypropylene and maleic anhydride-modified polyethylene.   The composite material according to claim 1, further comprising a styrene-olefin copolymer.   The composite material according to claim 9, wherein the styrene-olefin copolymer is a styrene / ethylene / butylene / styrene copolymer. The molded object which consists of a composite material in any one of Claims 1-10.