JP5672474B2 - Compatibilizer, thermoplastic resin composition and molded article - Google Patents

Description

  The present invention provides a biodegradable resin and a polyolefin resin compatibilizer, a biodegradable resin, a polyolefin resin and a thermoplastic resin composition containing the compatibilizer, and the thermoplastic resin composition. It is related with the molded object obtained.

  In recent years, enormous amounts of plastic products such as polyethylene, polypropylene, polystyrene, polyethylene terephthalate, and polyvinyl chloride have been used, and these waste treatments have been highlighted as one of the environmental problems. Currently, the disposal of plastic products uses incineration and burying. However, if the plastic product is disposed of by incineration, the burned calories are high, which can damage the incinerator and shorten the life. In addition, land is limited for the disposal of plastic products. Furthermore, when discarded in the natural environment, the resin has extremely high chemical stability, hardly decomposes by microorganisms or the like, and remains semipermanently. For this reason, it has caused problems such as polluting the living environment of marine organisms, which causes damage to the landscape.

  Under such circumstances, in recent years, biodegradable resins, which are resins that are biodegradable or decompose in a natural environment, have attracted attention. It is known that a biodegradable resin is gradually decomposed by hydrolysis or biodegradation in soil or water, and finally becomes a harmless degradation product due to the action of microorganisms.

  However, biodegradable resins, particularly aliphatic polyester resins, have insufficient mechanical properties and heat resistance, and have many problems in practical use. For example, polylactic acid-based resins that are aliphatic polyesters are used for applications such as films and sheets, but the mechanical properties and heat resistance of the resulting molded articles are inferior to petroleum-based thermoplastic resins.

  As a method for solving the above problem, for example, Patent Document 1 proposes a polymer having a methyl methacrylate unit as a compatibilizing agent for a polylactic acid resin and a polyolefin resin.

JP 2008-88364 A

  However, since the compatibilizer proposed in Patent Document 1 uses methyl methacrylate, which is an alkyl methacrylate having an alkyl group having 1 carbon atom, the compatibility between the polylactic acid resin and the polyolefin resin is high. It is not sufficient, and the resulting molded article has insufficient mechanical properties and heat resistance.

  It is an object of the present invention to provide a biodegradable resin and a polyolefin resin compatibilizer that give a molded article having excellent mechanical properties and heat resistance.

The present invention relates to a biodegradable resin (A) and the polyolefin resin (B) of the compatibility agent (C), compatibility comprising an alkyl methacrylate polymer containing i- butyl methacrylate unit 50 mass% It is an agent (C).

Further, the present invention is the biodegradable resin (A) 5 to 95 wt% and polyolefin resin (B) a thermoplastic the resin 100 parts by weight of the compatibilizing agent comprising 5-95 wt% (C) Is a thermoplastic resin composition containing 0.1 to 20 parts by mass.
Furthermore, this invention is a molded object obtained by shape | molding the said thermoplastic resin composition.

  By using the compatibilizer (C) of the present invention, a molded article having excellent compatibility of the biodegradable resin (A) and the polyolefin resin (B), and excellent mechanical properties and heat resistance is provided.

  The compatibilizer (C) of the present invention includes an alkyl methacrylate polymer containing 50% by mass or more of an alkyl methacrylate unit having an alkyl group having 2 to 6 carbon atoms.

  The alkyl methacrylate polymer contains 50% by mass or more of an alkyl methacrylate unit having an alkyl group having 2 to 6 carbon atoms.

The alkyl methacrylate unit is an alkyl methacrylate unit having an alkyl group having 2 to 6 carbon atoms.
When the carbon number of the alkyl group of the alkyl methacrylate unit is 2 or more, the dispersibility of the compatibilizer (C) in the biodegradable resin (A) and the polyolefin resin (B) is improved, and the resulting molding Excellent body mechanical properties and heat resistance. Moreover, when the carbon number of the alkyl group of the alkyl methacrylate unit is 6 or less, the powder handleability when the alkyl methacrylate polymer is powdered is excellent.
Among these alkyl methacrylate units, the dispersibility of the compatibilizer (C) in the biodegradable resin (A) and the polyolefin resin (B) and the powder when the alkyl methacrylate polymer is pulverized N-butyl methacrylate units, i-butyl methacrylate units, sec-butyl methacrylate units, and t-butyl methacrylate units having an alkyl group with 4 carbon atoms are preferable because of excellent handleability, and because of excellent molding processability, n -A butyl methacrylate unit and an i-butyl methacrylate unit are more preferable, and an i-butyl methacrylate unit is still more preferable.

The content of the alkyl methacrylate unit having an alkyl group having 2 to 6 carbon atoms in the alkyl methacrylate polymer is 50% by mass or more and 100% by mass or more in 100% by mass of all monomer units. Is preferred.
When the content of the alkyl methacrylate unit having an alkyl group having 2 to 6 carbon atoms in the alkyl methacrylate polymer is 50% by mass or more, the biodegradable resin (A) and the polyolefin resin (B) The dispersibility of the compatibilizing agent (C) is excellent, and the molded product obtained is excellent in mechanical properties and heat resistance.

  The alkyl methacrylate polymer containing 50% by mass or more of an alkyl methacrylate unit having an alkyl group having 2 to 6 carbon atoms is a simple substance containing 50% by mass or more of an alkyl methacrylate (m1) having an alkyl group having 2 to 6 carbon atoms. It is obtained by polymerizing the monomer component (m).

Examples of the alkyl methacrylate (m1) include ethyl methacrylate, n-propyl methacrylate, i-propyl methacrylate, n-butyl methacrylate, i-butyl methacrylate, sec-butyl methacrylate, t-butyl methacrylate, 2-methylbutyl methacrylate, 3 -Methyl butyl methacrylate, n-pentyl methacrylate, n-hexyl methacrylate, cyclohexyl methacrylate. These alkyl methacrylate (m1) may be used individually by 1 type, and may use 2 or more types together.
When the carbon number of the alkyl group of the alkyl methacrylate (m1) is 2 or more, the dispersibility of the compatibilizer (C) in the biodegradable resin (A) and the polyolefin resin (B) becomes good, and Excellent mechanical properties and heat resistance of the molded product. Moreover, when the carbon number of the alkyl group of the alkyl methacrylate (m1) is 6 or less, the powder handleability when the alkyl methacrylate polymer is powdered is excellent.
Among these alkyl methacrylates (m1), the dispersibility of the compatibilizer (C) in the biodegradable resin (A) and the polyolefin resin (B) and when the alkyl methacrylate polymer is pulverized. Because of excellent powder handling properties, n-butyl methacrylate, i-butyl methacrylate, sec-butyl methacrylate, and t-butyl methacrylate, which are alkyl methacrylates having an alkyl group having 4 carbon atoms, are preferable, and because of excellent molding processability. N-butyl methacrylate and i-butyl methacrylate are more preferred, and i-butyl methacrylate is more preferred.

  The monomer component (m) may include other copolymerizable monomer (m2) in addition to the alkyl methacrylate (m1) having an alkyl group having 2 to 6 carbon atoms, as necessary.

  Examples of the other monomer (m2) include aromatic vinyl monomers such as styrene, α-methylstyrene and chlorostyrene; vinyl cyanide monomers such as acrylonitrile and methacrylonitrile; methyl acrylate, n- Alkyl acrylates such as butyl acrylate, i-butyl acrylate, t-butyl acrylate and dodecyl acrylate; methyl methacrylate; alkyl methacrylates having 7 or more alkyl groups such as dodecyl methacrylate; carboxyl groups such as acrylic acid and methacrylic acid Vinyl monomer; vinyl monomer having a hydroxyl group such as 2-hydroxyethyl acrylate and 2-hydroxyethyl methacrylate; vinyl monomer having a glycidyl group such as glycidyl acrylate and glycidyl methacrylate; Vinyl acetate, vinyl carboxylate vinyl butyrate; methyl ether, vinyl ethers such as vinyl ethyl ether ethylene, propylene, olefins isobutylene; butadiene, isoprene diene monomers dimethyl butadiene and the like. These other monomers (m2) may be used individually by 1 type, and may use 2 or more types together.

The composition of the monomer component (m) is such that the content of the alkyl methacrylate (m1) having an alkyl group having 2 to 6 carbon atoms is 50% by mass or more in 100% by mass of all monomers, and other monomers The content of (m2) is 50% by mass or less, the content of the alkyl methacrylate (m1) having an alkyl group having 2 to 6 carbon atoms is 70% by mass or more, and the content of other monomers (m2) Is preferably 30% by mass or less.
When the content of the alkyl methacrylate (m1) having an alkyl group having 2 to 6 carbon atoms is 50% by mass or more, a compatibilizer in the biodegradable resin (A) and the polyolefin resin (B) ( The dispersibility of C) is good, and the resulting molded article is excellent in mechanical properties and heat resistance.
When the content of the other monomer (m2) is 50% by mass or less, the dispersibility of the compatibilizer (C) in the biodegradable resin (A) and the polyolefin resin (B) becomes good. The resulting molded article is excellent in mechanical properties and heat resistance.

  As a polymerization method for obtaining an alkyl methacrylate polymer, a known polymerization method can be used, and examples thereof include a radical polymerization method and an ionic polymerization method. Among these polymerization methods, the radical polymerization method is preferable from the viewpoint of productivity and production cost.

  As a polymerization system for obtaining an alkyl methacrylate polymer, a known polymerization system can be used, and examples thereof include bulk polymerization, suspension polymerization, and emulsion polymerization. Among these polymerization systems, emulsion polymerization obtained in powder form or granule form is preferable because of excellent powder handling characteristics when alkyl methacrylate polymer is powdered.

  As the emulsifier in the emulsion polymerization, a known emulsifier can be used, and examples thereof include an anionic emulsifier, a cationic emulsifier, and a nonionic emulsifier. Among these emulsifiers, anionic emulsifiers such as sulfonate compounds, sulfate compounds, and phosphate ester compounds are preferable. These emulsifiers may be used individually by 1 type, and may use 2 or more types together.

  As a polymerization initiator in emulsion polymerization, a known polymerization initiator can be used. For example, persulfate compounds such as potassium persulfate and sodium persulfate; t-butyl hydroperoxide, cumene hydroperoxide, benzoylperperoxide Examples thereof include organic peroxides such as oxides; azo compounds such as azobisisobutyronitrile; redox polymerization initiators in which the persulfate compound or the organic peroxide and a reducing agent are combined.

  The polymerization temperature in emulsion polymerization is usually 40 to 80 ° C., although it depends on the type of polymerization initiator.

The mass average particle diameter of the alkyl methacrylate polymer obtained by emulsion polymerization is preferably 50 to 500 nm, and more preferably 50 to 250 nm.
When the mass average particle diameter of the alkyl methacrylate polymer is 50 nm or more, it is possible to suppress the influence of coloring of the molded product and deterioration of mechanical properties due to the emulsifier. In addition, when the mass average particle diameter of the alkyl methacrylate polymer is 500 nm or less, it is easy to control the molecular weight when obtaining a high molecular weight alkyl methacrylate polymer.

  As a method for powderizing an alkyl methacrylate polymer latex obtained by emulsion polymerization, a known method can be used, and examples thereof include a coagulation method and a spray drying method.

The mass average molecular weight of the alkyl methacrylate polymer is preferably 5,000 to 20 million, more preferably 20,000 to 5,000,000, still more preferably 60,000 to 500,000, and 80,000. It is especially preferable that it is -300,000. The mass average molecular weight is measured by gel permeation chromatography.
When the mass average molecular weight of the alkyl methacrylate polymer is 5,000 or more, the resulting molded article has excellent heat resistance. Further, when the mass average molecular weight of the alkyl methacrylate polymer is 20 million or less, the resulting molded article has excellent tensile elongation characteristics.

  The compatibilizing agent (C) of the present invention may contain additives such as a stabilizer, an ultraviolet absorber and an antiblocking agent in addition to the alkyl methacrylate polymer.

  The thermoplastic resin composition of the present invention is a compatibilizer with respect to 100 parts by mass of the thermoplastic resin containing 5 to 95% by mass of the biodegradable resin (A) and 5 to 95% by mass of the polyolefin resin (B). (C) 0.1-20 mass part is included.

As a compounding quantity of a compatibilizing agent (C), it is 0 with respect to 100 mass parts of thermoplastic resins containing 5-95 mass% of biodegradable resin (A) and 5-95 mass% (B) of polyolefin resin. It is 1-20 mass parts, and it is more preferable that it is 0.5-15 mass parts.
When the blending amount of the compatibilizing agent (C) is 0.1 parts by mass or more, the blending effect of the compatibilizing agent (C) is exhibited, and the resulting molded article is excellent in mechanical properties and heat resistance. Moreover, the original characteristic of the thermoplastic resin containing biodegradable resin (A) and polyolefin resin (B) is not impaired as the compounding quantity of a compatibilizing agent (C) is 20 mass parts or less.

The biodegradable resin (A) of the present invention refers to a resin that decomposes by hydrolysis or biodegradation in soil, water, composting apparatus, or the like. Examples of biodegradable resins include aliphatic polyester resins; cellulose ester compounds such as cellulose acetate; polysaccharides such as biocellulose and starch-based plastics and starch-modified products; polyamide resins; A polyvinyl alcohol-type resin is mentioned. These biodegradable resins (A) may be used alone or in combination of two or more.
Among these biodegradable resins (A), aliphatic polyester resins are preferable from the viewpoints of moldability, production cost, mechanical properties, and heat resistance.

  Examples of the aliphatic polyester resin include hydroxycarboxylic acid polymers. Examples of the hydroxycarboxylic acid include lactic acid, glycolic acid, 3-hydroxybutyric acid, 4-hydroxybutyric acid, 3-hydroxyvaleric acid, 4-hydroxyvaleric acid, and 6-hydroxycaproic acid.

Aliphatic polyester resins are roughly classified into microbial production polymers, synthetic polymers, and semi-synthetic polymers. Examples of the microorganism-producing polymer include polyhydroxybutyric acid and polyhydroxyvaleric acid. Examples of the synthetic polymer include polycaprolactone, a condensate of an aliphatic dicarboxylic acid and an aliphatic diol. Examples of the semisynthetic polymer include a polylactic acid polymer. These aliphatic polyester resins may be used alone or in combination of two or more.
Among these aliphatic polyester resins, a semi-synthetic polymer is preferable and a polylactic acid polymer is more preferable from the viewpoint of processability and biodegradability. In particular, polylactic acid-based polymers can synthesize lactic acid from non-petroleum raw materials such as sweet potatoes and corn, and therefore can respond to the movement of replacing resins that do not use petroleum resources with resins that use petroleum resources. .

  Examples of the polylactic acid polymer include polylactic acid or a copolymer of lactic acid and other monomers. These polylactic acid-type polymers may be used individually by 1 type, and may use 2 or more types together.

  The other monomer may be a compound having two or more ester bond-forming functional groups, and examples thereof include dicarboxylic acid, polyhydric alcohol, hydroxycarboxylic acid, and lactone.

Examples of the dicarboxylic acid include succinic acid, azelaic acid, sebacic acid, terephthalic acid, and isophthalic acid.
Examples of the polyhydric alcohol include aromatic polyhydric alcohols such as compounds obtained by addition reaction of bisphenol with ethylene oxide; ethylene glycol, propylene glycol, butanediol, hexanediol, octanediol, glycerin, sorbitan, trimethylolpropane, neopentyl Examples include aliphatic polyhydric alcohols such as glycol; ether glycols such as diethylene glycol, triethylene glycol, polyethylene glycol, and polypropylene glycol.
Examples of the hydroxycarboxylic acid include glycolic acid, hydroxybutylcarboxylic acid, and hydroxycarboxylic acid described in JP-A-6-184417.
Examples of the lactone include glycolide, ε-caprolactone glycolide, ε-caprolactone, β-propiolactone, δ-butyrolactone, β- or γ-butyrolactone, pivalolactone, and δ-valerolactone.

  As a method for synthesizing the polylactic acid polymer, a known synthesis method can be used. Examples of the method for synthesizing a polylactic acid-based polymer include a synthesis method described in JP-A-7-33861; a synthesis method described in JP-A-59-96123; Volume, 3198-3199, and the synthesis method described. Specific examples include a synthesis method by direct dehydration condensation of lactic acid and a synthesis method by ring-opening polymerization of lactide.

Examples of lactic acid include L-lactic acid, D-lactic acid, and DL-lactic acid. These lactic acids may be used alone or in combination of two or more.
Examples of the lactide include L-lactide, D-lactide, DL-lactide, and meso-lactide. These lactides may be used individually by 1 type, and may use 2 or more types together.

  As a method for synthesizing lactide, a known synthesis method can be used. As a method for synthesizing lactide, for example, a synthesis method described in US Pat. No. 4,057,537; a synthesis method described in EP-A-261572; Polymer Bulletin, 14, 491-495 (1985) Described synthesis method; Makromol Chem. 187, 1611-1628 (1986).

  The content of the lactic acid unit in the polylactic acid-based polymer can be appropriately adjusted depending on the mechanical properties and biodegradability of the obtained molded product, but from the viewpoint of hydrolyzability, the total content in the polylactic acid-based polymer In 100 mol% of monomer units, it is preferably 50 mol% or more, and more preferably 70 mol% or more.

  As a structural ratio (L / D) of the L lactic acid unit and the D lactic acid unit in the lactic acid unit in the polylactic acid-based polymer, L / D is preferably 100/0 to 60/40 mol%, and L / D is It is more preferable that it is 100 / 0-80 / 20 mol%.

  The mass average molecular weight of the polylactic acid-based polymer is preferably 50,000 to 500,000, and more preferably 100,000 to 300,000. The mass average molecular weight is measured by gel permeation chromatography.

A known polyolefin resin can be used as the polyolefin resin (B) of the present invention. Examples of the polyolefin resin (B) include polypropylene (PP), high density polyethylene (HDPE), low density polyethylene (LDPE), linear low density polyethylene (LLDPE), poly-1-butene, polyisobutylene, and ethylene. -Random copolymer or block copolymer of propylene, random copolymer or block copolymer of ethylene-propylene-1-butene, ethylene-propylene-diene terpolymer, ethylene or propylene and cyclopentadiene Random copolymer in which vinyl monomer such as vinyl acetate, methacrylic acid ester, acrylic acid ester, and aromatic vinyl monomer is added to 50% by mass or less with respect to copolymer or ethylene or propylene. , Block copolymers or graft polymers. These polyolefin resin (B) may be used individually by 1 type, and may use 2 or more types together.
Among these polyolefin-based resins (B), PP, HDPE, LDPE, LLDPE, ethylene-propylene random copolymer or block copolymer is preferable from the viewpoint of versatility, productivity, and production cost.

  The thermoplastic resin of the present invention contains 5 to 95% by mass of the biodegradable resin (A) and 5 to 95% by mass of the polyolefin resin (B).

  The composition ratio of the biodegradable resin (A) and the polyolefin resin (B) can be appropriately set according to the use of the obtained molded article, and the total of the biodegradable resin (A) and the polyolefin resin (B). In 100% by mass, the content of the biodegradable resin (A) is 5 to 95% by mass, the content of the polyolefin resin (B) is 5 to 95% by mass, and the content of the biodegradable resin (A) Is 10 to 90% by mass, and the polyolefin resin (B) content is preferably 10 to 90% by mass.

  The thermoplastic resin composition of the present invention may contain additives such as a modifier, a stabilizer, a lubricant, and a filler as necessary.

As the modifier, a known modifier may be used, and examples thereof include a graft polymer that is a modifier for modifying the mechanical properties of the obtained molded article.
A graft polymer which is a modifier for modifying the mechanical properties of a molded product is usually obtained by graft polymerization of a vinyl monomer on a rubbery polymer.
Examples of the rubbery polymer include butadiene rubber containing butadiene rubber, silicone rubber containing polyorganosiloxane, and acrylic rubber containing polyalkyl (meth) acrylate rubber. These rubbery polymers may be used individually by 1 type, and may use 2 or more types together.
Examples of vinyl monomers include aromatic vinyl monomers, methacrylic acid esters, acrylic acid esters, and vinyl cyanide monomers. These vinyl monomers may be used alone or in combination of two or more.
The polymerization system for obtaining the graft polymer is not particularly limited, but emulsion polymerization is preferred.
Note that “(meth) acrylate” means “acrylate” or “methacrylate”.

Examples of the stabilizer include pentaerythrityl-tetrakis- [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate], triethylene glycol-bis- [3- (3-t-butyl). -5-methyl-4-hydroxyphenyl) propionate] and the like; phosphorus stabilizers such as tris (monononylphenyl) phosphite and tris- (2,4-di-t-butylphenyl) phosphite A sulfur stabilizer such as dilauroyl dipropionate. These stabilizers may be used individually by 1 type, and may use 2 or more types together.
The blending amount of the stabilizer is preferably 0.01 to 1 part by mass and more preferably 0.05 to 0.5 part by mass with respect to 100 parts by mass of the thermoplastic resin. When the blending amount of the stabilizer is 0.01 parts by mass or more, the blending effect of the stabilizer is exhibited. Further, when the blending amount of the stabilizer is 1 part by mass or less, the production cost is low and the original properties of the thermoplastic resin are not impaired.

Examples of the lubricant include sodium, calcium, and magnesium salts of saturated or unsaturated fatty acids such as lauric acid, palmitic acid, oleic acid, and stearic acid. These lubricants may be used individually by 1 type, and may use 2 or more types together.
It is preferable that the compounding quantity of a lubricant is 0.1-2 mass parts with respect to 100 mass parts of thermoplastic resins. When the blending amount of the lubricant is 0.1 parts by mass or more, the blending effect of the lubricant is exhibited. Further, when the blending amount of the lubricant is 2 parts by mass or less, the production cost is low and the original properties of the thermoplastic resin are not impaired.

As the filler, those having various shapes such as a fibrous shape, a particulate shape, a powder shape, a plate shape, and a needle shape can be used. Examples of fillers include glass fibers (including those coated with metals), carbon fibers (including those coated with metals), potassium titanate, asbestos, silicon carbide, silicon nitride, ceramic fibers, metal fibers, and aramids. Fiber, barium sulfate, calcium sulfate, calcium silicate, calcium carbonate, magnesium carbonate, antimony trioxide, zinc oxide, titanium oxide, magnesium oxide, iron oxide, molybdenum disulfide, magnesium hydroxide, aluminum hydroxide, mica, talc, kaolin , Pyrophyllite, bentonite, sericite, zeolite, wollastonite, alumina, clay, ferrite, graphite, gypsum, glass beads, glass balloon, quartz. These fillers may be used individually by 1 type, and may use 2 or more types together. Among these fillers, talc, calcium carbonate, and magnesium hydroxide are preferable.
The blending amount of the filler is preferably 0.1 to 50 parts by mass, and more preferably 1 to 50 parts by mass with respect to 100 parts by mass of the thermoplastic resin. When the blending amount of the filler is 0.1 parts by mass or more, the blending effect of the filler is expressed. Further, when the blending amount of the filler is 50 parts by mass or less, the manufacturing cost is low and the original properties of the thermoplastic resin are not impaired.

  The thermoplastic resin composition of the present invention can be kneaded by a known method. Examples of the kneading method include a kneading method using a mill roll, a Banbury mixer, a super mixer, and an extruder.

  The molded article of the present invention is obtained by molding the thermoplastic resin composition of the present invention. Examples of the molding method for obtaining the molded body of the present invention include an injection method, a melt extrusion method, and a calendar method. By the said molding method, molded objects, such as an injection molded product, a sheet | seat, a film, and a deformed material, can be obtained.

  The molded article of the present invention is suitable for packaging materials; food containers; building materials; miscellaneous goods such as toys and stationery; automobile parts; OA equipment;

EXAMPLES Hereinafter, although an Example demonstrates this invention concretely, this invention is not limited to these Examples.
In the examples, “parts” and “%” indicate “parts by mass” and “% by mass”.

(1) Polymerization rate A sample obtained by diluting 1 g of latex of an alkyl methacrylate polymer with 10 g of acetone was prepared by gas chromatography (model name “7890”, manufactured by Agilent Technologies), column (trade name “HP-5”, Using an inner diameter of 0.25 mm, a length of 30 m, a film thickness of 0.25 μm, manufactured by Agilent Technologies, Inc., the amount of monomer component remaining in the latex was measured, and the amount of monomer component remaining was determined as a single amount. The polymerization rate of the body component was calculated. Methyl isobutyl ketone was used as an internal standard substance.

(2) Mass average molecular weight The mass average molecular weight of the alkyl methacrylate polymer was measured by gel permeation chromatography (model name “HLC-8220”, manufactured by Tosoh Corporation) using the tetrahydrofuran-soluble content of the alkyl methacrylate polymer as a sample. ), Column (trade name “TSK-GEL SUPERMULTIPORE HZ-H”, manufactured by Tosoh Corporation), eluent: tetrahydrofuran, measurement temperature: 40 ° C., and a mass average molecular weight is determined from a standard polystyrene calibration curve. It was.

(3) Mass average particle diameter The mass average particle diameter of the alkyl methacrylate polymer (A) was measured using a particle size distribution meter (model name “CHDF2000 type”, manufactured by MATEC). The measurement conditions were standard conditions recommended by MATEC. That is, using an exclusive particle separation capillary cartridge and carrier liquid, alkyl methacrylate system under conditions of liquidity: almost neutral, flow rate: 1.4 ml / min, pressure: about 4000 psi (2600 KPa), temperature: 35 ° C. A 0.1 ml sample in which the latex of the polymer (A) was diluted to a concentration of about 3% was used for the measurement. As the standard particle size substance, a total of 12 monodisperse polystyrenes with known particle sizes were used in the range of 20 to 800 nm.

(4) Tensile elongation at break The tensile elongation at break of the molded product was measured according to JIS K-7113. In addition, the JIS1 test piece (thickness 4mm) obtained by injection molding was used as a molded object.

(5) Deflection temperature under load Deflection temperature under load of the compact was measured according to ISO 75 under the condition of a load of 0.45 MPa. In addition, the test piece (length 12.7mm, height 4mm, width 10mm) obtained by injection molding was used as a molded object.

[Example 1]
The following monomer mixture was stirred for 6 minutes at 10,000 rpm using a homomixer to obtain an emulsified mixture.
Monomer mixture:
i-Butyl methacrylate 100 parts Sodium dodecylbenzenesulfonate 1 part Deionized water 300 parts The emulsified mixture is put into a separable flask equipped with a thermometer, a nitrogen introduction tube, a cooling tube and a stirring device, and the inside of the container is replaced with nitrogen. did. Next, the internal temperature was raised to 60 ° C., and 0.15 part of potassium persulfate was added. Thereafter, heating and stirring were continued for 2 hours at an internal temperature of 60 ° C. to complete the polymerization, and an alkyl methacrylate polymer latex was obtained. From the gas chromatograph, the polymerization rate of the monomer was 99% or more. The obtained latex of alkyl methacrylate polymer was dropped into 100 parts of hot water containing 5 parts of calcium acetate to coagulate the latex. The obtained solidified product was separated and washed, and then dried at 65 ° C. for 16 hours to obtain an alkyl methacrylate polymer. The obtained alkyl methacrylate polymer was used as a compatibilizer (C1).

[Examples 2-11, Comparative Examples 1-2]
An alkyl methacrylate polymer was obtained in the same manner as in Example 1 except that the monomer component, the initiator amount, and the chain transfer agent amount were changed as shown in Table 1. From the gas chromatograph, the monomer polymerization rate was 99% or more. The obtained alkyl methacrylate polymers were used as compatibilizers (C2) to (C13), respectively.
In addition, n-octyl mercaptan was used as the chain transfer agent.

  Table 1 shows the mass average molecular weight and the mass average particle diameter of the alkyl methacrylate polymers obtained in Examples 1 to 11 and Comparative Examples 1 and 2.

尚、表１記載の略号は、以下の化合物を示す。
ｉ−ＢＭＡ：ｉ−ブチルメタクリレート
ｎ−ＢＭＡ：ｎ−ブチルメタクリレート
ＭＭＡ ：メチルメタクリレート
ＧＭＡ ：グリシジルメタクリレート
ｎ−ＢＡ ：ｎ−ブチルアクリレート

The abbreviations listed in Table 1 indicate the following compounds.
i-BMA: i-butyl methacrylate n-BMA: n-butyl methacrylate MMA: methyl methacrylate GMA: glycidyl methacrylate n-BA: n-butyl acrylate

[Examples 12 to 26, Comparative Examples 3 to 9]
Polylactic acid resin (trade name “LACEA H100”, manufactured by Mitsui Chemicals, Inc.) as biodegradable resin (A), polypropylene (trade name “Novatech FY-4”, Nippon Polypro (B) as polyolefin resin (B) Co., Ltd.), using (C1) to (C13) obtained in Examples 1 to 11 and Comparative Examples 1 and 2 as a compatibilizer (C), and blended in proportions shown in Tables 2 to 4, Melt-kneading was performed using a twin screw extruder having an inner diameter of 30 mm (φ30 mm) and L (cylinder effective length) / D (caliber) = 28.5 to obtain pellets of a thermoplastic resin composition. Thereafter, the obtained pellets were injection-molded at a molding temperature of 220 ° C. using an injection molding machine (model name “SE-100DU”, manufactured by Sumitomo Heavy Industries, Ltd.) to obtain a molded body.

  Tables 2 to 4 show the tensile elongation at break and the deflection temperature under load of the molded bodies obtained in Examples 12 to 26 and Comparative Examples 3 to 9.

  As is apparent from Table 2, the molded products obtained using the compatibilizers (C1) to (C11) of the present invention were excellent in tensile elongation at break and deflection temperature under load. On the other hand, the molded body obtained using the compatibilizers (C12) and (C13), which are alkyl methacrylate polymers having an alkyl group having 1 carbon atom, was inferior in tensile elongation at break and deflection temperature under load. . Moreover, the molded object obtained without using the compatibilizer (C) was inferior in tensile elongation at break and deflection temperature under load.

  As is clear from Tables 3 and 4, similar results were obtained even when the composition ratio of the biodegradable resin (A) and the polyolefin resin (B) was changed.

  Since the molded product obtained using the compatibilizer of the present invention is excellent in mechanical properties and heat resistance, packaging materials; food containers; building materials; miscellaneous goods such as toys and stationery; automobile parts; OA equipment; Is preferred.

Claims (5)

A biodegradable resin (A) and the polyolefin resin (B) of the compatibility agent (C),
A compatibilizer (C) comprising an alkyl methacrylate polymer containing 50% by mass or more of i-butyl methacrylate units. The weight average molecular weight of the alkyl methacrylate polymer is 5 1000-20000000 a is claim 1, wherein the compatibility agent (C). The weight average molecular weight of the alkyl methacrylate polymer is from 60,000 to 500,000 and is claim 1, wherein the compatibility agent (C). Relative to 100 parts by weight of a thermoplastic resin containing 5 to 95 wt% biodegradable resin (A) 5 to 95 wt% and polyolefin resin (B), compatibility of any one of claims 1 to 3 A thermoplastic resin composition containing 0.1 to 20 parts by mass of the agent (C).   The molded object obtained by shape | molding the thermoplastic resin composition of Claim 4.