JPH1160871A - Recyclability improver for polyolefin resin, use thereof, and production thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a recyclability improver which, in thermally melt molding a polyolefin resin waste, improves the meltability of the waste lowered by degradation and thus imparts a good moldability to the waste without detriment to the surface appearance of the resultant molded item by compounding polytetrafluoroethylene (A) with a polymer of an alkyl (meth)acrylate (B) having a specified number of carbon atoms. SOLUTION: The amt. of the improver added is such that the content of ingredient A per 100 pts.wt. polyolefin resin is 0.001-20 pts.wt. The improver is produced by mixing an aq. dispersion of ingredient A having a particle size of 0.05-1.0 μm with an aq. dispersion of ingredient B and spray drying he resultant mixture. The wt. ratio of ingredient A to ingredient B is set at 0.2 or higher. The content of ingredient A in the improver is pref. 0.05-40 wt.%. A polyolefin resin to be recycled is an olefin homo- or copolymer or a copolymer formed mainly from a major amt. of an olefin monomer and a minor amt. of a vinyl monomer or the like.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a recyclability improver for polyolefin resins, a method for using the same, and a method for producing the same.

[0002]

2. Description of the Related Art Plastic products are inexpensive, lightweight, and excellent in durability, so that they can be used as films, sheets, or various small and large molded products as food packaging materials and containers. It is used in a great number of applications, such as building materials, agricultural materials, containers, and home appliances. When these plastic products become waste, their superior durability becomes a disadvantage, and the decay rate is extremely slow, making them unsuitable for landfill disposal. It is the current situation. However, plastic generates a large amount of heat and not only damages the incinerator, but also generates a large amount of carbon dioxide gas, which poses a problem from the viewpoint of global environmental protection. Also,
Not only is there a problem with waste management,
From the viewpoint of resource saving, it is a social demand to recycle useful waste, and it is also required to recycle plastic as much as possible.

[0003] Plastics have an extremely large number of seeds, their characteristics are completely different depending on the kind, and there are many incompatible combinations. Therefore, when recycling, it is necessary to separate these. Resin is used in a very large amount and has excellent mechanical properties as well as stability such as weather resistance, so it is often used for large molded products such as containers. is there. For this reason, if it becomes possible to recycle the waste of polyolefin resin products, it will meet social needs for environmental protection such as waste reduction and resource saving, and its significance is extremely large. is there.

[0004] Until now, waste of polyolefin resin products has been recycled, and after passing through such processes as separation, crushing, and removal of foreign matter, an antioxidant,
Additives such as processing stabilizers are mixed and heated and melt-molded, processed into round bars, square bars, plate materials or molded products of various complex shapes, surveying piles, marker piles, benches, earth retaining materials, packing, containers It is used as such.

When processing a polyolefin resin,
Phenolic antioxidants, thioether antioxidants, phosphorus antioxidants, ultraviolet absorbers, light stabilizers, etc. to prevent thermal oxidation deterioration at the processing temperature and oxidation deterioration or photooxidation deterioration in the use environment Are used in combination, and these additives are also used in the production of recycled products. However, because polyolefin resin is used for a long period of time under harsh conditions such as outdoors, taking advantage of its excellent durability, it often deteriorates remarkably when it becomes waste. It is not possible to obtain a product with excellent properties simply by diverting the additives used when processing the polyolefin resin of the above, and in severe cases, it will not be possible to even form the product due to gelling or burning in the molding machine There was something. Therefore, it is strongly desired to find an additive suitable for recycling, which enables processing of such a significantly deteriorated polyolefin resin.

For example, Japanese Patent Application Laid-Open No. Hei 4-233958 discloses that a hydroxylamine compound is added to a polyolefin resin containing a phenolic antioxidant which has been colored by long-term aging and reworked to reduce coloring. It has been proposed to reuse. Also,
Japanese Unexamined Patent Publication (Kokai) No. 3-174449 discloses that the durability of a plastic gasoline tank is improved by adding a hindered phenol antioxidant, a phosphorus antioxidant, a hindered amine light stabilizer and carbon black to high-density polyethylene, It has been proposed to allow recycling. Furthermore, JP-A-6-155473,
JP-A-6-184350 proposes a combination of a specific phenolic antioxidant and a specific cyclic phosphite antioxidant as additives suitable for recycling waste of polyolefin resin products. I have.

However, these methods only suppress the further deterioration of the properties of the deteriorated polyolefin resin. When a polyolefin resin product is heated and melt-molded for recycling, it is necessary to provide good moldability by restoring the melt tension reduced by deterioration to the state before deterioration. Such a purpose cannot be achieved by a combination of an agent, a light stabilizer and the like.

From the viewpoint of improving the melt tension, a polyolefin resin having improved processability is disclosed in JP-A-62-121.
No. 704, JP-A-2-298536 and the like disclose polypropylene having a free-end long-chain branched structure. This propylene can maintain the strength of the resin film at the time of foam molding due to its unique viscoelastic properties. As a result, it is possible to produce a foam having highly independent cells, which cannot be obtained with conventional linear polypropylene. It is possible.
However, such a polypropylene requires a special treatment method such as electron beam irradiation or addition of a peroxide to generate a free-end long-chain branched structure, or a synthetic method. It has the disadvantage of being significantly higher.

Further, polytetrafluoroethylene has a high crystallinity and a low intermolecular force, so that it has a property of forming fibers with a slight stress. It has been improved and used as an additive for thermoplastic resins.

For example, JP-A-5-214184 and JP-A-6-306212 disclose resin compositions obtained by blending polytetrafluoroethylene with polyolefin. JP-A-7-324147 discloses a method for producing a polyolefin-based resin composition in which polytetrafluoroethylene and a dispersion medium powder are mixed under high shear, the polytetrafluoroethylene is fiberized in advance, and then mixed with the polyolefin. Have been.

However, polytetrafluoroethylene has poor dispersibility with respect to a general thermoplastic resin containing no halogen atom, and is described in JP-A-5-214184 and JP-A-6-306212. As described above, there is a disadvantage that the surface appearance of the molded article is significantly reduced without being uniformly dispersed by simply blending.

It is also difficult to fiberize all polytetrafluoroethylene by shearing force by the method disclosed in Japanese Patent Application Laid-Open No. Hei 7-324147, and the fiberized polytetrafluoroethylene also aggregates in the matrix resin. As a result, a uniform composition cannot be obtained.

That is, all of these methods have a problem in the dispersibility of polytetrafluoroethylene in a matrix resin, and require a large amount of polytetrafluoroethylene to exhibit the above-mentioned useful properties. To
There is a disadvantage that the surface appearance of the molded article is impaired.

[0014] Accordingly, an object of the present invention is to improve the melt tension reduced by deterioration, impart good moldability, and provide a low cost, when the waste of a polyolefin resin product is heated and melted and recycled. An object of the present invention is to provide a recyclability improver that does not impair the surface appearance of a molded article and a method for using the same.

[0015]

As a result of diligent studies to solve the above-mentioned problems, a resin composition containing polytetrafluoroethylene and an alkyl (meth) acrylate having 5 to 30 carbon atoms was produced using a waste product of a polyolefin resin product. Of the polyolefin resin reduced by deterioration by shredding or pulverizing and adding during heat-melt molding to improve the melt tension of the polyolefin resin, thereby obtaining a molded article having a good surface appearance, and reached the present invention.

The gist of the present invention is to provide a recyclability improver for polyolefin resins containing polytetrafluoroethylene (A) and an alkyl (meth) acrylate polymer (B) having 5 to 30 carbon atoms, a method for using the same and a method for producing the same. It is in.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION The polyolefin resin used as a recycled material in the present invention may be, for example, a homopolymer or copolymer of an olefin monomer obtained by radical polymerization, ionic polymerization or the like; Copolymers of a monomer and an inferior amount of a vinyl monomer, a copolymer of an olefin monomer and a diene monomer, and the like. Used in combination of more than one species.

The olefinic monomer referred to herein includes:
Examples thereof include ethylene, propylene, butene-1, hexene-1, decene-1, octene-1, and 4-methyl-pentene-1, with ethylene and propylene being particularly preferred. Specific examples of the olefin-based monomer homopolymer or copolymer include low-density polyethylene, ultra-low-density polyethylene, ultra-low-density polyethylene, linear low-density polyethylene, high-density polyethylene, ultra-high-molecular-weight polyethylene, polypropylene , Ethylene-propylene copolymer, polymethylpentene, polybutene and the like. These olefin polymers are used alone or in combination of two or more. Among these, a polyolefin resin containing, as a main component, one or a mixture of two or more selected from the group consisting of polyethylene, polypropylene, and ethylene-propylene copolymer is particularly preferable.

In the method of the present invention, only a used polyolefin resin can be used, but if necessary, a used polyolefin resin and an unused polyolefin resin can be mixed and used.

The recyclability improver of the present invention is not particularly limited to polytetrafluoroethylene (A).
It is obtained by polymerizing a monomer containing tetrafluoroethylene as a main component by a known method. As long as the characteristics of the polytetrafluoroethylene are not impaired, the copolymerization component may contain a fluorine-containing olefin such as hexafluoropropylene, chlorotrifluoroethylene, fluoroalkylethylene, or perfluoroalkylvinyl ether, or a perfluoroalkyl (meth) acrylate or the like. Fluoroalkyl (meth) acrylates can be included. The content of the copolymer component is preferably 10% by weight or less based on tetrafluoroethylene.

In the melt tension improver of the present invention, the alkyl (meth) acrylate polymer (B) having 5 to 30 carbon atoms is a radical polymerization of a monomer containing an alkyl (meth) acrylate having 5 to 30 carbon atoms. Alternatively, it is obtained by polymerizing by ionic polymerization or the like. Specific examples of the alkyl (meth) acrylate having 5 to 30 carbon atoms include cyclohexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, nonyl (meth) acrylate, dodecyl (meth) acrylate, tridecyl (meth) acrylate, and octadecyl. (Meth) acrylate, isobornyl (meth) acrylate and the like can be mentioned. These monomers can be used alone or in combination of two or more. Examples of the monomer copolymerizable with the alkyl (meth) acrylate having 5 to 30 carbon atoms include styrene, p-methylstyrene, o-methylstyrene, p-chlorostyrene, o-chlorostyrene, p-methoxystyrene, and o. Styrene-based monomers such as methoxystyrene, 2,4-dimethylstyrene and α-methylstyrene; C1 to C1 such as methyl (meth) acrylate, ethyl (meth) acrylate and butyl (meth) acrylate
4 alkyl (meth) acrylate monomers; vinyl cyanide monomers such as acrylonitrile and methacrylonitrile; vinyl ether monomers such as vinyl methyl ether and vinyl ethyl ether; carboxyls such as vinyl acetate and vinyl butyrate Vinyl acid monomers; ethylene, propylene,
Olefin monomers such as isobutylene; diene monomers such as butadiene, isoprene, and dimethylbutadiene; These monomers can be used alone or in combination of two or more.

The recyclability improver of the present invention comprises the polytetrafluoroethylene (A) and the alkyl (meth) acrylate polymer having 5 to 30 carbon atoms (B), wherein (B) / (A ) Is preferably 0.2 or more, more preferably 0.5 or more. (B) /
If the weight ratio of (A) is less than 0.2, the dispersibility of polytetrafluoroethylene may decrease.

The amount of polytetrafluoroethylene in the recyclability improver of the present invention is preferably 0.05 to 40% by weight based on the total weight of the recycle improver. 0.0
If it is less than 5%, the amount added to obtain a sufficient melt tension becomes too large, and the rigidity and heat resistance of the polyolefin resin may be impaired. If it exceeds 40% by weight, the dispersibility of polytetrafluoroethylene may decrease.

By blending such a recyclability improver such that the content of polytetrafluoroethylene is 0.001 to 20 parts by weight per 100 parts by weight of the recycled polyolefin resin, The fluoroethylene component is uniformly dispersed in the form of fine fibrils, and the melt tension is improved without impairing the surface appearance of the molded product, and a regenerated polyolefin resin composition having good moldability can be obtained.

The recyclability improver of the present invention comprises an aqueous dispersion of polytetrafluoroethylene particles having a particle diameter of 0.05 to 1.0 μm and an aqueous dispersion of alkyl (meth) acrylate polymer particles having 5 to 30 carbon atoms. It is obtained as a powder by the first manufacturing method of mixing and coagulating or spray drying. Further, in a dispersion obtained by mixing an aqueous dispersion of polytetrafluoroethylene particles having a particle diameter of 0.05 to 1.0 μm and an aqueous dispersion of alkyl (meth) acrylate-based polymer particles having 5 to 30 carbon atoms, ethylenic non-emulsion is further added. It can also be obtained as a powder by a second production method in which a monomer having a saturated bond is polymerized and then coagulated or spray-dried.

The aqueous dispersion of polytetrafluoroethylene particles used for producing the recyclability improver of the present invention can be obtained by emulsion polymerization of a monomer containing tetrafluoroethylene as a main component.

Commercially available raw materials for the polytetrafluoroethylene particle dispersion include Fluon AD-1 and AD-936 manufactured by Asahi ICI Fluoropolymer Co., Ltd., Polyflon D-1 and D-2 manufactured by Daikin Industries, and Mitsui DuPont Fluorochemicals. A typical example is Teflon 30J manufactured by the company.

The aqueous dispersion of alkyl (meth) acrylate-based polymer particles having 5 to 30 carbon atoms used for producing the recyclability improver of the present invention contains the above-mentioned 5 to 30 carbon atoms.
Can be obtained by polymerizing a monomer containing an alkyl (meth) acrylate by a known emulsion polymerization method or a miniemulsion polymerization method.

The aqueous dispersion of polytetrafluoroethylene particles having a particle diameter of 0.05 to 1.0 μm and the aqueous dispersion of alkyl (meth) acrylate polymer particles having 5 to 30 carbon atoms in the second production method of the recyclability improver of the present invention. The monomer having an ethylenically unsaturated bond to be further polymerized in the dispersion mixed with the dispersion is not particularly limited, and styrene, p-methylstyrene, o-methylstyrene, p-chlorostyrene, o-chlorostyrene are used. Styrene monomers such as styrene, p-methoxystyrene, o-methoxystyrene, 2,4-dimethylstyrene, α-methylstyrene; methyl (meth) acrylate, ethyl (meth) acrylate;
(Meth) acrylate monomers such as butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, dodecyl (meth) acrylate, cyclohexyl (meth) acrylate, glycidyl (meth) acrylate, and 2-hydroxyethyl (meth) acrylate Vinyl cyanide monomers such as acrylonitrile and methacrylonitrile; vinyl ether monomers such as vinyl methyl ether and vinyl ethyl ether; vinyl carboxylate monomers such as vinyl acetate and vinyl butyrate; ethylene, propylene;
An olefin monomer such as isobutylene can be selected from diene monomers such as butadiene, isoprene, prene, and dimethylbutadiene. These monomers can be used alone or in combination of two or more.

The mixing of the recyclability improver of the present invention into the recycled polyolefin resin is carried out by melt-kneading by a known method such as extrusion kneading or roll kneading. Further, after mixing the melt tension improver of the present invention and a part of the polyolefin resin to prepare a master batch, another stage of mixing such as further adding and mixing a recycled polyolefin resin is also possible.

The recycled polyolefin resin composition to which the recyclability improver of the present invention is added has an increased tension at the time of melting, drawability at the time of calendering, drawdown of the molten resin at the time of thermoforming or blow molding, and foaming. Improved foaming of cells during molding, calendering, thermoforming,
Workability such as blow molding and foam molding is improved. In addition, the discharge amount during extrusion molding, the surface condition of extruded articles such as sheets and films, and the extrudability are also improved. Also, there is no macro-aggregate of polytetrafluoroethylene, and the surface appearance of the molded product is excellent.

The recycled polyolefin resin composition to which the recyclability improver of the present invention has been added may further contain a filler. The amount of the filler is 0.1 to 400 parts by weight based on 100 parts by weight of the recycled polyolefin resin composition.
It is preferable that the amount is part by weight, and the addition of the filler improves rigidity and heat resistance, improves workability such as prevention of adhesion to a roll surface in calendering and the like, and achieves cost reduction. If the amount is less than 0.1 part by weight, the effect of improving rigidity is not sufficient, and if it exceeds 400 parts by weight, the surface properties tend to decrease. Typical examples of fillers include calcium carbonate, talc, glass fiber, magnesium carbonate, mica, kaolin, calcium sulfate, barium sulfate, titanium white, white carbon, carbon black, ammonium hydroxide, magnesium hydroxide, and aluminum hydroxide. It is listed as. Calcium carbonate, talc and the like are preferred.

The recycled polyolefin resin composition to which the recyclability improver of the present invention has been added may further contain additives such as a stabilizer, a lubricant and a flame retardant, if necessary. Examples of the stabilizer include pentaerythrityl-tetrakis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate], triethylene glycol-
Phenolic stabilizers such as bis [3- (3-t-butyl-5-methyl-4-hydroxyphenyl) propionate], tris (monononylphenyl) phosphite,
Phosphorus stabilizers such as tris (2,4-di-t-butylphenyl) phosphite, sulfur stabilizers such as dilaurylthiodipropionate, and lubricants such as lauric acid, palmitic acid, oleic acid or stearic acid Sodium, calcium or magnesium salts, and flame retardants include trimethyl phosphate, triethyl phosphate, tributyl phosphate, trioctyl phosphate, tributoxyethyl phosphate, triphenyl phosphate, tricresyl phosphate, cresyl phenyl phosphate, octyl diphenyl phosphate , Diisopropylphenyl phosphate, tris (chloroethyl) phosphate, alkoxy-substituted bisphenol A bisphosphate, hydroquinone bisphosphate, resorcy Bisphosphate, phosphoric acid ester compounds such as polyphosphates such trioxybenzene phosphate, tetrabromobisphenol A,
Decabromodiphenyl oxide, hexabromocyclododecane, octabromodiphenyl ether, bistribromophenoxyethane, ethylenebistetrabromophthaleimide, tribromophenol, various halogenated epoxy oligomers obtained by the reaction of halogenated bisphenol A with epihalohydrin, halogen Representative examples thereof include carbonate oligomers containing halogenated bisphenol A, halogen-containing compounds such as halogenated polystyrene, chlorinated polyolefins and polyvinyl chloride, metal hydroxides, metal oxides, and sulfamic acid compounds.

Examples of the method for processing the recycled polyolefin resin composition to which the recyclability improver of the present invention is added include calendering, thermoforming, blow molding, foam molding, extrusion molding, injection molding, and melt spinning. it can.

Useful molded articles obtained by using the recycled polyolefin resin composition to which the recyclability improver of the present invention is added include sheets, films, thermoformed articles, hollow molded articles, foams, injection molded articles, fibers and the like. And the like.

Hereinafter, the present invention will be described with reference to Examples.
The present invention is not limited to these.

[0037]

EXAMPLES In each description, "parts" indicate parts by weight and "%" indicates% by weight.

Various physical properties described in Reference Examples, Examples and Comparative Examples are measured by the following methods.

(1) Solid content concentration: 170 ° C. of the particle dispersion
And dried for 30 minutes.

(2) Particle size distribution, weight average particle size: The particle dispersion was diluted with water and used as a sample solution, and a dynamic light scattering method (ELS800 manufactured by Otsuka Electronics Co., Ltd., temperature 25 ° C., scattering angle 90) Degree).

(3) Zeta potential: 0.01% of particle dispersion
A sample diluted with a mol / l NaCl aqueous solution was used as a sample solution and measured by electrophoresis (ELS800 manufactured by Otsuka Electronics Co., Ltd., temperature 25 ° C., scattering angle 10 °).

(4) Melt tension: Pellets of resin composition are dropped into a flow tester (Capillograph manufactured by Toyo Seiki Co., Ltd.)
The strand was extruded at a constant extrusion rate (downward speed: 10 mm / min), the strand was taken out at a constant speed (4 m / min), and the melt tension was measured. Die L / D is 10.0mm / Φ
2.0 mm and the measurement temperature were 200 ° C.

(5) Swelling ratio: The pellets of the resin composition were subjected to a constant flow rate (1.5 mm / descent rate) using a descending flow tester (Capillograph manufactured by Toyo Seiki Co., Ltd.).
min), and the diameter (D) of the strand at a position 5 mm below the nozzle was measured and calculated by the following equation. The L / D of the die was 10.0 mm / Φ2.0 mm, and the measurement temperature was 190 ° C.

(Swelling ratio) = D (mm) /
2.0 (6) Melt flow rate: 230 ° C. according to ASTM D 1238 using pellets of the resin composition;
It was measured at 16 kg.

(7) Flexural modulus: The resin composition pellet was roll-kneaded at 200 ° C. and press-molded to obtain a test piece, which was measured according to ASTM D790.

(8) Roll Sheet Appearance: Using a pellet of the resin composition, the appearance of the roll sheet at the time of roll mixing was visually determined. ：: The surface has no irregularities and the gloss is excellent. Δ: The surface has some irregularities and the gloss is slightly inferior. ×: The surface has irregularities and the gloss is inferior. Reference Example 1 <Polydodecyl methacrylate-based polymer particle dispersion (B-1) Production> 0.1 part of azobisdimethylvaleronitrile was dissolved in a mixed solution of 50 parts of dodecyl methacrylate and 50 parts of methyl methacrylate. 2.0 parts of sodium dodecylbenzenesulfonate and 300 parts of distilled water
Part of the mixed solution, and mix with a homomixer at 10,000 rpm.
After stirring for 2 minutes at 300 m / m, 300 kg /
Passing ^{twice at} a pressure of cm ² gave a stable pre-dispersion. This is charged into a separable flask equipped with a stirring blade, a condenser, a thermocouple, and a nitrogen inlet, the internal temperature is increased to 80 ° C. under a nitrogen stream, and the mixture is stirred for 3 hours to undergo radical polymerization to disperse polymer particles. A liquid (hereinafter referred to as B-1) was obtained.

The solid concentration of B-1 was 25.1%, the particle size distribution showed a single peak, and the weight average particle size was 191%.
nm, and the surface potential was -58 mV.

Reference Example 2 <Recyclability improver for polyolefin resin (C-1)
Production of Asahi ICI Fluoropolymers Fluon AD936 was used as a polytetrafluoroethylene-based particle dispersion. The solid concentration of AD936 is 63.0%,
It contains 5% of polyoxyethylene alkylphenyl ether based on polytetrafluoroethylene.
The particle size distribution of AD936 showed a single peak, the weight average particle size was 290 nm, and the surface potential was -20 mV.

Add 83.3 parts of AD936 to distilled water.
7 parts were added to obtain a polytetrafluoroethylene particle dispersion A-1 having a solid content concentration of 26.2%. A-1 is 25%
Of polytetrafluoroethylene particles and 1.2% of polyoxyethylene alkyl phenyl ether.

120 parts of A-1 (polytetrafluoroethylene 30 parts) and 199.2 parts of B-1 (50 parts of dodecyl methacrylate / methyl methacrylate copolymer)
Into a separable flask equipped with a stirring blade, a condenser, a thermocouple, and a nitrogen inlet.
Stirred for hours. Thereafter, the temperature inside the system was raised to 80 ° C. and maintained for 1 hour, and then 0.001 part of iron (II) sulfate, 0.003 part of disodium ethylenediaminetetraacetate, 0.24 part of Rongalite salt, and 60.8 parts of distilled water And a mixture of 20 parts of methyl methacrylate and 0.4 part of tertiary butyl peroxide was added dropwise over 1 hour. After the completion of the addition, the internal temperature was maintained at 80 ° C. for 1 hour to complete the radical polymerization. Was. No solid matter was separated through a series of operations, and a uniform particle dispersion was obtained. The solids concentration of the particle dispersion is 2
At 5.2%, the particle size distribution was relatively broad and the weight average particle size was 252 nm. This particle dispersion is poured into 400 parts of 90 ° C. hot water containing 5 parts of calcium chloride,
The solid was separated, filtered and dried to obtain 98 parts of a powder of a melt tension improver for polyolefin resin (hereinafter referred to as C-1).

Example 1 As a polyolefin resin, a homopolypropylene pellet EA9 (manufactured by Nippon Polychem Co., Ltd.) was used.
(5 g / 10 min), the melt tension, the swelling ratio, the melt flow rate, the flexural modulus, and the appearance of the roll sheet were evaluated. next,
Pulverized test piece obtained by press-forming an unused product 1
With respect to 00 parts, the recyclability improver C obtained in Reference Example 1 was used.
After hand blending with 0.2 parts of -1 added, a twin screw extruder (ZSK manufactured by WERNER & PFLEIDERER)
Using 30), the mixture was melt-kneaded at a barrel temperature of 200 ° C. and a screw rotation speed of 200 rpm, and formed into pellets.
The obtained pellet is referred to as a recycled product a1. Various physical properties were evaluated using the regenerated product a1. Further, for 100 parts of a crushed test piece obtained by press-molding the regenerated product a1,
A pellet of a regenerated product a2 was obtained in the same manner as the regenerated product a1 by adding 0.2 part of C-1 obtained in Reference Example 1. Various physical properties were evaluated using the recycled product a2. Similarly, pellets of the recycle product a3 were obtained from the recycle product a2, and various physical properties were evaluated. Table 1 shows the results of the recycled products a1 to a3.

[0052]

[Table 1]

Comparative Example 1 For comparison, pellets of regenerated products b1 to b3 were obtained in the same manner as in Example 1 except that the recyclability improver C-1 was not added, and various physical properties were evaluated. Table 2 shows the results.

[0054]

[Table 2]

Comparative Example 2 For comparison, pellets of regenerated products c1 to c3 were obtained in the same manner as in Example 1 except that 0.2 part of powdery polytetrafluoroethylene was used instead of the recyclability improver C-1 of the present invention. Was. Table 3 shows the results of evaluating the various physical properties. Fluon CD123 manufactured by Asahi ICI Fluoropolymers Co., Ltd. was used as the powdered polytetrafluoroethylene.

[0056]

[Table 3]

The composition containing the recyclability-improving agent of the present invention shows no change in physical properties typified by a decrease in the melt tension at the time of regeneration, and has a drawability during calendering, thermoformability, blow moldability, It can be confirmed that the foam moldability and the like are as good as the unused products. In addition, it can be confirmed that the appearance of the composition is good.

[0058]

By incorporating the recyclability improver of the present invention at the time of regenerating polyolefin resin waste, a decrease in tension during melting can be prevented, and take-up properties during calendering, thermoformability, blow moldability, and foam moldability can be prevented. , Etc., can be favorably maintained. Further, since the dispersibility in the polyolefin resin is extremely good, a regenerated product having a good surface appearance can be obtained.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI C08L 33/06 C08L 33/06 // (C08L 23/00 27:18 33:06)

Claims (5)

[Claims] 1. A recyclability improver for a polyolefin resin comprising polytetrafluoroethylene (A) and an alkyl (meth) acrylate polymer having 5 to 30 carbon atoms (B). 2. The waste of a polyolefin resin product is shredded or pulverized, heated and melt-molded, and recycled for use in 100 parts by weight of the polyolefin resin constituting the waste of the polyolefin resin product. A method for recycling polyolefin resin products, comprising adding a recyclability improver so that the content of polytetrafluoroethylene (A) is 0.001 to 20 parts by weight. 3. An aqueous dispersion of polytetrafluoroethylene (A) particles having a particle size of 0.05 to 1.0 μm and a carbon number of 5 to 5.
30 alkyl (meth) acrylate-based polymer (B)
The method for producing a recyclability improver for a polyolefin resin according to claim 1, wherein the aqueous dispersion of the particles is mixed and powdered by coagulation or spray drying. 4. An aqueous dispersion of polytetrafluoroethylene (A) particles having a particle diameter of 0.05 to 1.0 μm and a carbon number of 5 to
30 alkyl (meth) acrylate-based polymer (B)
In a dispersion obtained by mixing an aqueous dispersion of particles, a monomer having an ethylenically unsaturated bond is polymerized and then powdered by coagulation or spray drying, and the recyclability improver for polyolefin resin according to claim 1 is obtained. How to make. 5. A recyclability improver for a polyolefin resin comprising polytetrafluoroethylene (A), an alkyl (meth) acrylate polymer having 5 to 30 carbon atoms (B) and a polyolefin resin (C).