JP2005232228A - Resin composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a resin composition which comprises a poly-3-hydroxybutyrate-based polymer and/or polylactic acid and a polyethylene-based resin and has a large rate of crystallization and excellent impact resistance. <P>SOLUTION: This resin composition is characterized by comprising 1 to 99 wt. % of the poly-3-hydroxybutyrate-based polymer and/or the polylactic acid and 99 to 1 wt. % of the polyethylene-based resin and satisfying the following characteristics (a) and (b). (a) The crystal-melting point observed with a differential scanning calorimeter, when heated from room temperature at a temperature-rising rate of 10°C / min, is 130 to 185°C. (b) The weight-average mol. wt. converted into polystyrene and measured by gel permeation chromatography is 20,000 to 3,000,000. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a resin composition comprising a poly-3-hydroxybutyrate polymer and / or polylactic acid and a polyethylene resin, which is excellent in impact resistance and exhibits a high crystallization rate.

  Since poly-3-hydroxybutyrate-based polymers and polylactic acid are obtained from plants as raw materials, they have recently attracted attention as materials with little environmental impact. However, poly-3-hydroxybutyrate-based polymers and polylactic acid have problems that the crystallization speed is slow and the molding processability is inferior and the impact resistance is also inferior. The cycle had to be lengthened, and when forming by extrusion, it was necessary to reduce the discharge amount or introduce a large apparatus with a long production line.

  As a method for solving these problems, a method of mixing polycaprolactone or polybutylene succinate resin has been proposed (for example, see Patent Documents 1 and 2).

  In addition, as a method for improving the crystallization speed of poly-3-hydroxybutyrate polymer or polylactic acid and improving the molding processability thereof, a method of adding a plasticizer or a crystal nucleating agent to the pellet has been proposed. 1) A method of adding a plasticizer such as fatty acid, aliphatic ester, aliphatic amide, or fatty acid metal salt (see, for example, Patent Document 3). 2) Adding silicon nitride as a crystal nucleating agent to increase the crystal growth rate. Method (for example, refer to Patent Document 4), 3) A method for increasing the crystal growth rate by adding ammonium chloride as a crystal nucleating agent (for example, see Patent Document 5)

JP-A-9-194281

JP 11-323141 A JP-A-7-188573 European Published Patent No. 0291024 International Patent Publication No. 91/197559

  However, in the method of mixing the different polymers proposed in Patent Documents 1 and 2, the impact resistance effect is not sufficient. Further, in the method of adding a plasticizer proposed in Patent Document 3, the plasticizer bleeds to the product surface or the plasticizer migrates to other products, particularly to products made of polyvinyl chloride or polystyrene resins. There were problems such as rapid migration of plasticizers and contamination of production lines such as cooling rolls. Furthermore, in the method of adding the crystal nucleating agent proposed in Patent Documents 4 and 5, the crystal nucleating agent is expensive, and there are problems such as impairing the cost performance of the resin composition.

  The present invention provides a poly-3-hydroxybutyrate polymer and / or a resin composition comprising polylactic acid and a polyethylene resin, which has excellent molding processability and molded product productivity because of its high crystallization rate. It is.

  As a result of intensive studies to solve the above problems, the present inventor has demonstrated that the resin composition comprising a poly-3-hydroxybutyrate polymer and / or polylactic acid and a polyethylene resin has excellent moldability and impact resistance. As a result, the present invention has been completed.

That is, the present invention comprises a poly-3-hydroxybutyrate polymer and / or polylactic acid 1 to 99% by weight and a polyethylene resin 99 to 1% by weight, and has the following characteristics (a) and (b): The present invention relates to a resin composition characterized by being satisfied.
(A) With a differential scanning calorimeter, a crystalline melting point observed when heated at a temperature rising rate of 10 ° C./min from room temperature is 130 ° C. or higher and 185 ° C. or lower. (B) A chloroform-soluble component is measured by gel permeation chromatography. The weight average molecular weight (Mw) in terms of polystyrene in the process is 20,000 to 3,000,000. The present invention will be described in detail below.

  Examples of the poly-3-hydroxybutyrate polymer (hereinafter referred to as a PHB polymer) used in the present invention include other than poly-3-hydroxybutyrate homopolymer and 3-hydroxybutyrate / 3-hydroxybutyrate. Examples of the hydroxyalkanoate other than 3-hydroxybutyrate in the case of the copolymer include 3-hydroxypropionate, 3-hydroxyvalerate, 3-hydroxy Examples include hexanoate, 3-hydroxyheptanoate, 3-hydroxyoctanoate, 3-hydroxynonanoate, 3-hydroxydecanoate, 3-hydroxyundecanoate, 4-hydroxybutyrate, and hydroxylaurylate. The copolymer is particularly excellent in molding processability Since the resin composition is obtained, hydroxyalkanoate other than the 3-hydroxybutyrate is preferably one that is copolymerized than 25 mol%. In particular, poly-3-hydroxybutyrate homopolymer, 3-hydroxybutyrate / 3-hydroxyvalerate copolymer, and 3-hydroxybutyrate / 4-hydroxybutyrate copolymer are preferable because they are easily available. Moreover, since it becomes a resin composition excellent in molding processability, it is preferable that the PHB-based polymer is produced in a microorganism. Such a PHB polymer can be obtained as a commercial product. Moreover, as the manufacturing method, it can also obtain by the method currently disclosed by the US Patent 4477654 gazette, the international publication 94/115519 gazette, the US Patent 5502273 gazette, etc., for example. Moreover, as polylactic acid (hereinafter referred to as PLA), a commercially available product can be used without any particular limitation. For example, (trade name) Lacia (manufactured by Mitsui Chemicals, Inc.) is sold as a commercially available product. .

  In the resin composition of the present invention, it is also possible to use a mixture of a PHB polymer and PLA, and the PHB polymer / PLA weight ratio may be used in the range of 100/0 to 0/100. Among them, it is preferable to use only a PHB polymer without mixing PLA because a resin composition with little change in physical properties after molding can be obtained.

  The polyethylene resin used in the present invention refers to an ethylene homopolymer or copolymer. For example, high pressure low density polyethylene, high density polyethylene, ethylene / propylene copolymer, ethylene / 1-butene copolymer, ethylene / 1-hexene copolymer, ethylene / 1-octene copolymer, ethylene / 4- Methyl-1-pentene copolymer, ethylene / vinyl acetate copolymer, ethylene / acrylic acid copolymer, ethylene / methacrylic acid copolymer, ethylene / acrylic acid ester copolymer, ethylene / methacrylic acid ester copolymer These polyethylene resins may be used singly or in combination of two or more.

  The mixing ratio of the PHB polymer and / or PLA and the polyethylene resin in the resin composition of the present invention is 99/1 to 1/99 by weight ratio of (PHB polymer and / or PLA) / polyethylene resin, Preferably, it is 95/5 to 30/70, and more preferably 90/10 to 50/50. When the weight ratio of the polyethylene resin is less than 1%, the resulting resin composition is inferior in impact resistance. On the other hand, if it exceeds 99%, the resin composition obtained is inferior in moldability.

  The resin composition of the present invention has a crystalline melting point of 130 ° C. or higher and 185 ° C. observed when heated at a rate of temperature increase of 10 ° C./min from room temperature with a differential scanning calorimeter (hereinafter referred to as DSC). It is preferably 140 ° C. or more and 185 ° C. or less, and more preferably 150 ° C. or more and 185 ° C. or less, because it is a resin composition having excellent heat resistance and molding processability. Here, when the crystal melting point is less than 130 ° C., the resin composition is inferior in heat resistance. On the other hand, when it exceeds 185 ° C., the resin composition is inferior in molding processability. The crystal melting point in the present invention refers to DSC (trade name DSC-7, manufactured by Perkin Elmer Co., Ltd.), an aluminum pan loaded with 5 mg of sample, and the temperature of the pan is increased from room temperature to 10 ° C./min. It represents the highest temperature among the peak temperatures of the heat flux based on the crystal melting observed when heated at.

  Furthermore, since the resin composition of the present invention becomes a resin composition having a high crystallization rate and excellent molded product production efficiency, the DSC is heated from room temperature to 180 ° C. at a temperature rising rate of 80 ° C./min. After maintaining at 180 ° C. for 1 minute, the crystallization temperature after cooling at a rate of temperature decrease of 10 ° C./min is preferably 100 ° C. or higher and 170 ° C. or lower, particularly preferably 110 ° C. or higher and 165 ° C. or lower, more preferably 120 ° C. or higher and 160 ° C. It is preferable that it is below ℃. The crystallization temperature refers to DSC (manufactured by Perkin Elmer, trade name DSC-7), an aluminum pan loaded with 5 mg of sample, and the pan is heated from room temperature to 180 ° C./min at 180 ° C./min. The sample is heated up to 180 ° C., held at 180 ° C. for 1 minute, then cooled at a rate of temperature drop of 10 ° C./minute, and is the highest of the peak temperatures of the heat flux observed based on the crystallization of the PHB polymer and / or PLA. Represents a high temperature.

  The resin composition of the present invention has a polystyrene-reduced weight average molecular weight (hereinafter referred to as Mw) of 20000 or more and 3000000 or less when a chloroform-dissolved component is measured by gel permeation chromatography (hereinafter referred to as GPC). In particular, it is preferably 50,000 or more and 1,000,000 or less because the resin composition is excellent in moldability and excellent in mechanical strength when formed into a molded product. Here, when Mw is less than 20000, the resin composition is inferior in mechanical strength. On the other hand, when Mw exceeds 3000000, the resin composition is inferior in moldability. In addition, Mw of the chloroform melt | dissolution component of a resin composition can also be measured by the molecular weight of the melt | dissolution part obtained by melt | dissolving a molding in 60 degreeC chloroform for 2 hours. In addition, the measurement of Mw in the present invention uses a GPC apparatus (manufactured by Tosoh Corporation, trade name HLC8020GPC) equipped with two columns (trade name TSKgel GMHHR-H, manufactured by Tosoh Corporation) and measuring solvent: chloroform. Using a standard polystyrene (manufactured by Tosoh Corporation), the column elution volume was measured at a measurement temperature of 40 ° C., a sample dissolution condition: 60 ° C., and a sample prepared at a measurement concentration of 50 mg / 50 mL in 2 hours with an injection volume of 100 μL. This was calibrated.

  The resin composition of the present invention preferably contains 0.1 to 10% by weight of an acid-containing thermoplastic polyolefin because it is further excellent in impact resistance. The acid-containing thermoplastic polyolefin is one or more functional groups selected from the group consisting of a carboxylic acid group, a carboxylic acid group, a carboxylic acid anhydride group, an amide group, a hydroxyl group, and an epoxy group in its main chain or side chain. For example, a modified polyolefin obtained by grafting an unsaturated carboxylic acid or derivative thereof or other functional vinyl monomer onto the polyolefin can be exemplified. In this case, the polyolefin includes polyolefins such as high density polyethylene, medium density polyethylene, low density polyethylene, polypropylene, polybutene, poly-4-methylpentene-1, a copolymer of ethylene and α-olefin; ethylene-propylene elastomer, Polyolefin heat comprising ethylene-propylene-diene terpolymer elastomer, butyl elastomer, low crystalline ethylene-propylene copolymer or low crystalline ethylene-butene copolymer, or low crystalline propylene-butene copolymer Plastic elastomers; polyolefin elastomers mainly composed of a blend of polypropylene and ethylene-propylene elastomer; and ethylene-vinyl ester copolymers, ethylene-acrylic ester copolymers, etc. Look, a blend of various polyolefin mutual also be included. On the other hand, unsaturated carboxylic acids or derivatives thereof, and other functional vinyl monomers include, for example, unsaturated carboxylic acids such as acrylic acid, methacrylic acid, maleic acid, fumaric acid, itaconic acid, sorbic acid, and acid anhydrides thereof. Amides such as acrylic acid amide and methacrylic acid amide; epoxies such as glycidyl acrylate and glycidyl methacrylate; hydroxy compounds such as acrylic acid 2-hydroxy ester, methacrylic acid 2-hydroxy ester, and polyethylene glycol monoacrylate; acrylic Metal salts such as sodium acid, sodium methacrylate, zinc acrylate and the like can be mentioned, and they can be mixed and used. Of these, acrylic acid, maleic acid, and maleic anhydride give preferable results. In addition, when using said monomer, it can also be used simultaneously with various monomers, such as styrene, vinyl acetate, an acrylic ester, and a methacrylic ester, and can also be graft-copolymerized.

  Further, the amount of the unsaturated carboxylic acid or its derivative or other functional vinyl monomer contained in the graft-modified polyolefin used as the acid-containing thermoplastic polyolefin is preferably 0.05 to 20% by weight, more preferably 0. .5 wt% to 20 wt% is desirable.

  The resin composition of the present invention preferably contains 0.001 to 10% by weight of an epoxy compound because it further increases impact resistance. The epoxy compound preferably has an oxirane oxygen amount derived from an epoxy group of 1% by weight or more. Examples of the method for measuring the amount of oxirane oxygen include those described in Koichi Murai, “Plasticizers: Theory and Application” (published by Koshobo Publishing, published March 1, 1973, page 664).

  Examples of such epoxy compounds include epoxidized vegetable oils such as epoxidized soybean oil and epoxidized linseed oil; epoxidized elastomers such as epoxidized polybutadiene and epoxidized polyisoprene; glycidyl ester homopolymers such as glycidyl methacrylate; glycidyl methacrylate Copolymers of glycidyl esters such as styrene, acrylic acid, acrylic acid esters and other monomers having unsaturated double bonds; phthalic acid diglycidyl ester, ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, bisphenol A-epi A chlorohydrin type epoxy resin etc. can be mentioned, These 1 type or 2 types or more are used.

  Moreover, a commercially available epoxy compound can be used. For example, as epoxidized soybean oil (trade name) Adeka Sizer O-130P (manufactured by Asahi Denka Kogyo), (trade name) New Sizer 510R (manufactured by Nippon Oil & Fats) (Trade name) Kapox S-6 (made by Kao), etc., as epoxidized linseed oil (trade name) Adeka Sizer O-180A (made by Asahi Denka Kogyo), (trade name) New Sizer 512 (made by Nippon Oil & Fats), etc. As epoxidized polybutadiene (trade name) Epolide PB3600 (manufactured by Daicel Chemical Industries), (trade name) BF-1000 (manufactured by Asahi Denka Kogyo Co., Ltd.), etc. Can be mentioned.

  Since the resin composition of the present invention has further improved impact resistance, it preferably contains 0.001 to 10% by weight of an elastomer-modified polyolefin described in detail below. The elastomer-modified polyolefin is (i) 100 parts by weight of a modified polyolefin containing 0.01 to 15% by weight of a carboxyl group or acid anhydride group, and (ii) acrylic acid containing 0.01 to 5% by weight of a carboxyl group. 1 to 500 parts by weight of an ester copolymer elastomer and (iii) a metal salt corresponding to 0.1 to 30 equivalents of a carboxylic acid group or an acid anhydride group constituting the modified polyolefin of (i). preferable.

  Here, examples of the modified polyolefin containing (i) a carboxyl group or an acid anhydride group include maleic anhydride-modified polypropylene, maleic anhydride-modified polyethylene, and poly (ethylene-acrylic acid) copolymer. The amount of carboxyl group or acid anhydride group is preferably 0.01 to 15% by weight, more preferably 1 to 10% by weight. Further, (ii) the carboxylate-containing acrylic ester copolymer elastomer preferably has a carboxyl group content of 0.01 to 5% by weight, and more preferably 0.5 to 3% by weight. The blending amount is preferably 1 to 500 parts by weight, particularly preferably 30 to 300 parts by weight, based on 100 parts by weight of (i) the modified polyolefin. Furthermore, (iii) metal salts include, for example, metal alkoxides such as titanium tetrabutoxide, titanium tetraisopropoxide, zirconium tetrabutoxide, and dibutyltin dilaurate; metal acetates such as zinc acetate, lead acetate, magnesium acetate, and calcium acetate Salts: Metal hydroxides such as zinc hydroxide, iron hydroxide, aluminum hydroxide, magnesium hydroxide, and calcium hydroxide; Metal oxides such as iron oxide, calcium oxide, titanium oxide, zinc oxide, and aluminum oxide; Zinc chloride And salts of metals having a valence of 2 or more, such as metal halides such as calcium chloride, magnesium chloride, and magnesium chloride. There is virtually no limitation on the ligand of the metal salts. And it is preferable that this (iii) metal salt uses the quantity equivalent to 0.1-30 equivalent of the carboxyl group or acid anhydride group of said (i) modified polyolefin.

  The elastomer-modified polyolefin may be prepared by reacting in an organic solvent, or may be reacted during the melt mixing of the acrylate copolymer elastomer and the modified polyolefin.

  The resin composition of the present invention preferably contains 0.1 to 50% by weight of a layered silicate because the impact resistance is further improved. Examples of the layered silicate include smectites such as montmorillonite, beidellite, hectorite and saponite; swelling fluorinated mica such as Na-type fluorotetrasilicon mica, Na-type teniolite and Li-type teniolite; The layered silicate which does not contain aluminum and magnesium, etc. can be illustrated, These 1 type (s) or 2 or more types are mixed and used. Examples of the synthesis method include a melting method, an intercalation method, and a hydrothermal method. The layered silicate preferably contains an organic cation between layers because it is more effective in improving impact resistance. As a method of incorporating an organic cation between layers of the layered silicate, first, a layered silicate is used. Disperse the silicate in water or a polar organic solvent, add the above organic cation in the form of a salt to this, and mix with stirring. -The method of washing and drying is mentioned.

  Examples of the shape of the resin composition of the present invention include a pellet shape, a powder shape, a lump shape, and the like. Among them, the pellets are excellent in production efficiency at the time of manufacture and excellent in handleability at the time of molding. The shape is preferred. As a method for forming a pellet shape, for example, a strand cutting method in which a strand-shaped molten granule is cut with a strand cutter, an underwater cutting method in which a molten resin is cut in water, or the molten resin is cooled or cut by mist or the like. Examples include the hot-cut method and the sheet pelletizing method in which a sheet-shaped molten granule is cut with a sheet pelletizer. Among them, strand cutting is particularly possible because pellets with good resin bite can be obtained during injection molding and extrusion molding. Method, underwater cut method and hot cut method are preferably used.

  As a method for producing the resin composition of the present invention, since a resin composition having particularly good production efficiency and excellent moldability is obtained, the temperature of the molten resin discharged from the die of the extruder is 160 ° C. or higher and 185 ° C. or lower. It is preferable to produce using a kneader whose temperature is set to be. Examples of the kneader include, for example, a different-direction twin-screw extruder such as a same-direction twin-screw extruder and a conical twin-screw extruder; a batch mixer such as a Banbury mixer and a pressure kneader; and a roll kneader.

  When the resin composition of the present invention is produced, it is desirable to dry the PHB polymer and / or PLA in advance, and the drying conditions are arbitrary, for example, at a temperature of 40 to 90 ° C. for 30 minutes. It is preferable to dry for about 3 days. Further, when molding the resin composition of the present invention, it is desirable to dry the resin composition in advance, and the drying conditions are arbitrary, for example, at a temperature of 40 to 90 ° C. for 30 minutes to It is preferable to dry for about 3 days.

  The molding method of the resin composition of the present invention is arbitrary, and examples thereof include profile extrusion, film, sheet, blow, injection, foaming, extrusion coating, rotational molding, etc. Among them, the injection molding property is excellent. In the case of performing injection molding, if the temperature of the molten resin is 230 ° C. or lower, preferably 210 ° C. or lower, the time required for crystallization in the mold is small, and the molding cycle can be shortened.

  Examples of the resin composition of the present invention include calcium carbonate, mica, talc, silica, barium sulfate, calcium sulfate, kaolin, clay, pyroferrite, bentonite, sericite, zeolite, nepheline cinnite, attapulgite, wollastonite, ferrite, Inorganic fillers such as calcium silicate, magnesium carbonate, dolomite, antimony trioxide, titanium oxide, iron oxide, molybdenum disulfide, graphite, gypsum, glass beads, glass powder, glass balloon, glass fiber, quartz, quartz glass, montmorillonite Various kinds of plant fibers such as starch, cellulose fiber and kenaf; natural fillers such as wood flour, okara, fir shell, bran and organic fillers such as modified products thereof may be mixed. In particular, calcium carbonate and talc also have a function of increasing the crystallization speed, so it is desirable to add them. When a filler is added, the resin composition has an excellent balance between rigidity and impact resistance. Therefore, the filler is preferably used in an amount of 150 parts by weight or less with respect to 100 parts by weight of the resin composition of the present invention.

  Furthermore, it is also possible to add plasticizers such as fatty acids, aliphatic esters, aliphatic amides, and fatty acid metal salts to the resin composition of the present invention.

  In addition, the resin composition of the present invention may contain a crystal nucleating agent as necessary, which further increases the crystal growth rate. Examples of the crystal nucleating agent include nitrided nectar, mica, talc, alumina, calcium hydroxyapatite, and aluminum chloride. Among these, talc and silicon nitride are preferable. Further, it may contain a plasticizer such as fatty acid, aliphatic ester, aliphatic amide, fatty acid metal salt, etc., thereby further increasing the crystal growth rate.

  Furthermore, the resin composition of the present invention includes an antihydrolysis agent represented by carbodiimide, an antiblocking agent, a release agent, an antistatic agent, a slip agent, an antifogging agent, a lubricant, a heat resistance stabilizer, an ultraviolet ray, if necessary. Stabilizers, light stabilizers, weathering stabilizers, antifungal agents, rust inhibitors, ion trap agents, foaming agents, flame retardants, flame retardant aids, and the like may be included. Furthermore, other thermoplastic resins and rubbers, particularly thermoplastic resins called biodegradable resins may be blended.

  The resin composition of the present invention is used for the housing and structure of electrical products; automotive exterior parts such as bumpers, rocker moldings, side moldings, and over fenders; automotive interior parts such as carpets, head liners, door trims, sun visors, etc. For example, it is suitably used.

  Since the resin composition of the present invention has a high crystallization rate, it is excellent in molding processability, productivity of a molded product, and excellent in impact resistance.

  Hereinafter, the present invention will be described with reference to examples, but these are illustrative and the present invention is not limited to these examples.

  Various measurements in Examples and Comparative Examples are shown below.

~ Measurement of crystallization temperature ~
The crystal growth rate was measured using a differential scanning calorimeter (trade name DSC-7, manufactured by Perkin Elmer). A 5 mg sample is cut from the pellet and loaded into an aluminum pan. The pan is heated from room temperature to 180 ° C. at a heating rate of 80 ° C./min and held at 180 ° C. for 1 minute. Then, it cooled at the speed | rate of 10 degree-C / min, and measured the highest temperature among the peak temperature of the heat flux based on crystallization as crystallization temperature.

~ Measurement of crystal melting point ~
The crystal melting point was measured using a differential scanning calorimeter (trade name DSC-7, manufactured by Perkin Elmer). A 5 mg sample is cut from the pellet and loaded into an aluminum pan. The highest temperature among the peak temperatures of the heat flux based on crystal melting observed when the pan was heated from room temperature at a heating rate of 10 ° C./min was measured as the crystal melting point.

~ Measurement of weight average molecular weight ~
The molecular weight was measured by gel permeation chromatography using only the dissolved components obtained by dissolving the pellets obtained by granulation in chloroform at 60 ° C. for 2 hours. Calibration was performed using standard polystyrene (manufactured by Tosoh Corporation), and the weight average molecular weight (Mw) was determined in terms of polystyrene. The measurement conditions are shown below.
Model: Product name HLC8020GPC (manufactured by Tosoh Corporation)
Solvent: Chloroform sample dissolution conditions: 60 ° C, 2 hours temperature: 40 ° C
Measurement concentration: 50 mg / 50 mL
Injection volume: 100 μL
Column: Two trade names TSKgel GMHHR-H (manufactured by Tosoh Corporation) -Measurement of solidification time in injection molding-
Injection molding was performed using an injection molding machine (trade name IS100E, manufactured by Toshiba Machine Co., Ltd.), and the solidification time was measured. The set temperature is NH: 180 ° C., H1: 175 ° C., H2: 160 ° C., H3: 140 ° C., mold temperature: 60 ° C., injection pressure: 6.8 MPa, a total of 10 seconds of injection time and compensation time The injection molding was performed under the conditions, and after completion of the pressure-compensating step, the cooling time was increased every other second, and an attempt was made to take out the molded product with an ejector pin. The minimum cooling time during which the product can be taken out by ejection with an ejector pin was measured as the minimum solidification time. In addition, the temperature of the molten resin when molding is performed under these conditions is 183 ° C.

~ Measurement of Izod impact strength ~
The Izod impact strength at 23 ° C. was measured using a notched Izod test piece obtained by injection molding.

Example 1
Poly 3-hydroxybutyrate polymer (manufactured by PHB Industrial S / A, trade name Biocycle 1000) preliminarily dried in an oven at 80 ° C. for 4 hours in advance, 65% by weight, linear low density polyethylene (Tosoh Corporation) Manufactured, trade name Nipolon Z ZF260) 30% by weight, maleic anhydride modified polyethylene (manufactured by Sigma-Aldrich Co., Ltd., maleic anhydride modified amount 3 wt%) 4% by weight, epoxidized soybean oil (manufactured by Asahi Denka Kogyo Co., Ltd.) A compound consisting of 1% by weight (trade name Adeka Sizer O-130P) was prepared, and melt extrusion was performed using a different-direction twin screw extruder (trade name: Labo Blast Mill, manufactured by Toyo Seiki Seisakusho; resin temperature 181 ° C., rotation speed 60 rpm). Mix, solidify the extruded strand in a hot tub set at 60 ° C, and pelletize with a strand cutter To obtain a more resin composition.

  Table 1 shows the crystallization temperature, the crystal melting point, the weight average molecular weight of the chloroform-dissolved component, the solidification time in the injection molding, and the Izod impact strength of the obtained resin composition.

Example 2
Maleic anhydride having a molecular weight (Mw) of 15000 containing 28.6 g of a copolymer elastomer composed of ethyl acrylate, butyl acrylate and acrylonitonyl containing 1.0% by weight of carboxyl groups in a 500 ml beaker and 5% by weight of acid anhydride groups. 10.0 g of modified polypropylene and 200 ml of o-dichlorobenzene were added and dissolved at 90 ° C. with stirring to obtain a polymer solution. To this solution, a 10% aqueous solution of zinc acetate dihydrate equivalent to 7 times the number of moles of carboxylic acid was slowly added. A white precipitate formed with the addition of the aqueous metal salt solution. The precipitate was filtered and washed with water, and then dried under reduced pressure at 60 ° C. overnight to obtain an acrylate copolymer elastomer-modified polyolefin.

  Poly 3-hydroxybutyrate polymer (manufactured by PHB Industrial S / A, trade name Biocycle 1000) previously preliminarily dried in an oven at 80 ° C. for 4 hours, 65% by weight, ultra-low density polyethylene (manufactured by Tosoh Corporation) Trade name Lumitac 12-1) 30% by weight, acrylic ester copolymer elastomer-modified polyolefin 4% by weight obtained above, epoxidized soybean oil (trade name Adeka Sizer O-130P, manufactured by Asahi Denka Kogyo Co., Ltd.) A blend consisting of 1% by weight was prepared, melt-extruded and mixed in a different-direction twin-screw extruder (trade name: Labo Blast Mill, manufactured by Toyo Seiki Seisakusho; resin temperature 182 ° C., rotational speed 60 rpm), The resin composition was obtained by solidifying with a hot tub set at ° C. and pelletizing with a strand cutter.

  Table 1 shows the crystallization temperature, the crystal melting point, the weight average molecular weight of the chloroform-dissolved component, the solidification time in the injection molding, and the Izod impact strength of the obtained resin composition.

Example 3
Disperse 1500 g of Na montmorillonite (Kunimine Kogyo, trade name Kunipia F) in 100 liters of water at 80 ° C. and stir for 3 hours to make a suspension. After further stirring at 80 ° C. for 1 hour, filtration, washing, drying and pulverization yielded a layered silicate having an average particle size of 1.1 μm in which ammonium salts were ionically bonded between the layers.

  100 parts by weight of a poly 3-hydroxybutyrate polymer (trade name Biocycle 1000, manufactured by PHB Industrial S / A) preliminarily dried in an oven at 80 ° C. for 4 hours in an Henschel mixer having an internal volume of 10 liters, ethylene / acetic acid 40 parts by weight of a vinyl copolymer (trade name Ultrasen 760, manufactured by Tosoh Corporation), and precipitated calcium carbonate whose surface is treated with a fatty acid as calcium carbonate (trade name, white glossy CCR, manufactured by Shiroishi Kogyo Co., Ltd.) 0.12 μm) 40 parts by weight and 15 parts by weight of the layered silicate obtained as described above were charged and stirred at a rotational speed of 950 rpm for 5 minutes. The resin temperature immediately after mixing was 182 ° C. Immediately after the kneading, the obtained composite was put on a roll molding machine to form a sheet and cooled and solidified. Then, it was made into a pellet shape with a sheet pelletizer.

  Table 1 shows the crystallization temperature, the crystal melting point, the weight average molecular weight of the chloroform-dissolved component, the solidification time in the injection molding, and the Izod impact strength of the obtained resin composition.

Example 4
Instead of linear low-density polyethylene (trade name Nipolon Z ZF260, manufactured by Tosoh Corporation), an ethylene-propylene copolymer (manufactured by JSR, product name JSR EP02P) is used, and talc (product manufactured by Fuji Talc Co., Ltd., product) No. LSM # 300) The same method as in Example 1 except that 30 parts by weight of layered silicate used in Example 3 and 10 parts by weight of polylactic acid (trade name Lacia H440 manufactured by Mitsui Chemicals, Inc.) were added. Thus, a resin composition was obtained.

  Table 1 shows the crystallization temperature, the crystal melting point, the weight average molecular weight of the chloroform-dissolved component, the solidification time in the injection molding, and the Izod impact strength of the obtained resin composition.

Comparative Example 1
Pellets were obtained in the same manner as in Example 1 except that the extrusion was performed only with the PHB polymer.

  Table 1 shows the crystallization temperature, the crystal melting point, the weight-average molecular weight of the dissolved chloroform, the solidification time in the injection molding, and the Izod impact strength. The obtained resin was inferior in Izod impact strength.

Comparative Example 2
Pellets were obtained in the same manner as in Example 1 except that the temperature setting of the extruder was changed and the temperature of the molten resin was 215 ° C.

  Table 1 shows the crystallization temperature, the crystal melting point, the weight-average molecular weight of the dissolved chloroform, the solidification time in the injection molding, and the Izod impact strength. The obtained resin had a long solidification time and was inferior in moldability.

Claims (5)

A poly 3-hydroxybutyrate polymer and / or polylactic acid 1 to 99% by weight and a polyethylene resin 99 to 1% by weight, satisfying the following characteristics (a) and (b): Resin composition.
(A) With a differential scanning calorimeter, a crystalline melting point observed when heated at a temperature rising rate of 10 ° C./min from room temperature is 130 ° C. or higher and 185 ° C. or lower. (B) A chloroform-soluble component is measured by gel permeation chromatography. The weight average molecular weight (Mw) in terms of polystyrene at the time of 20,000 to 3,000,000 The resin composition according to claim 1, further comprising 0.1 to 10% by weight of an acid-containing thermoplastic polyolefin. The resin composition according to claim 1, further comprising 0.001 to 10% by weight of an epoxy compound. Further, (i) 100 parts by weight of a modified polyolefin containing 0.01 to 15% by weight of a carboxyl group or acid anhydride group, and (ii) an acrylate copolymer elastomer containing 0.01 to 5% by weight of a carboxyl group 0.001 to 10% by weight of an elastomer-modified polyolefin comprising 1 to 500 parts by weight and a metal salt corresponding to 0.1 to 30 equivalents of a carboxylic acid group or an acid anhydride group constituting the modified polyolefin of (iii) (i) The resin composition according to claim 1, comprising: Furthermore, 0.1-50 weight% of layered silicate is contained, The resin composition of Claims 1-4 characterized by the above-mentioned.