JP2013163742A - Resin composition, method for producing the same, and molded product thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a resin composition capable of producing a molded product having excellent rigidity and heat resistance.SOLUTION: A resin composition includes: 1-58 wt.% of an aliphatic polyester-based polymer (A); 0.5-50 wt.% of elastomers (B); 0.5-50 wt.% of an ethylene-based polymer (C) containing an epoxy group; 10-58 wt.% of a propylene-based polymer (D); 1-50 wt.% of plant fibers (E); and 1-50 wt.% of a modified propylene-based polymer (F) (provided that the total weight of the aliphatic polyester-based polymer (A), the elastomers (B), the ethylene-based polymer (C) containing an epoxy group, the propylene-based polymer (D), the plant fibers (E), and the modified propylene-based polymer (F) is 100 wt.%).

Description

  The present invention relates to a resin composition, a production method thereof, and a molded body thereof.

In recent years, it has been studied to replace a resin produced from petroleum as a raw material with an aliphatic polyester polymer produced from a plant as a raw material, in particular, a polylactic acid resin. In addition, the use of plant fibers as reinforcing fibers has been studied.
For example, Patent Document 1 includes 20 to 60 parts by weight of a polylactic acid resin (A), 83 to 58% by weight of the following copolymer (b1), 0.5 to 7% by weight of the following polymer (b2), Propylene resin formed by blending 1 to 10% by weight of the polymer (b3) and 15 to 25% by weight of the following talc (b4) (however, the total amount of (b1) to (b4) is 100% by weight). Composition (B) 40 to 80 parts by weight (however, the total amount of (A) and (B) is 100 parts by weight), plant natural fiber (C) 1 to 50 parts by weight, and modified propylene Automotive parts manufactured from a polylactic acid-based resin composition containing 0.1 to 20 parts by weight of resin (D); (b1) n-decane soluble content at 23 ° C. is 17 to 25% by weight (However, the weight of the copolymer (b1) is 100% by weight.) Crystalline propylene block copolymer having a rate (MFR: ASTM D 1238, 230 ° C., load 2160 g) of 20 to 40 g / 10 minutes, (b2) Molecular weight distribution Mw measured by gel permeation chromatography (GPC) method / Mn is 10 or more and the molecular weight distribution Mz / Mw is 3.5 or more, (b3) Melt flow rate (MFR: ASTM D 1238, 190 ° C., load 2160 g) is 1 to 20 g / 10 An ethylene / 1-butene random copolymer having an ethylene content of 40 to 95% by weight (provided that the weight of the copolymer (b3) is 100% by weight), (b4) Talc that is .5 to 3.5 μm is disclosed.

Patent Document 2 discloses that the propylene polymer (A) is 10 to 89% by mass, the polylactic acid resin (B) is 10 to 89% by mass, and the ethylene polymer (C) 1 to 1 is an epoxy group-containing polymer. The propylene polymer (A) contains a propylene-ethylene random copolymer component, and the propylene-ethylene random copolymer component 135 is a propylene-based resin composition containing 50% by mass. Propylene resin composition having an intrinsic viscosity ([η] _EP ) measured in a tetralin solvent at 5 ° C. of 3.5 to 10 dl / g (provided that the propylene resin (A) and the polylactic acid resin (B) And the total content of the ethylene-based polymer (C) containing an epoxy group is 100% by mass).
Further, Patent Document 3 discloses a polyolefin polymer (A), an aliphatic polyester polymer (B), and a melt flow rate measured at 190 ° C. under a load of 21 N of 0.5 to 3.0 g / 10 min. The resin composition containing the elastomers (C) and the polyolefin polymer (D) having an epoxy group is disclosed.

  Patent Document 4 discloses a method for producing a resin composition containing (A) a biodegradable resin and (C) a polyolefin-based resin, wherein (A) the biodegradable resin, (B) the ( A) A first kneading step for producing a resin composition precursor by kneading a biodegradable resin and a reactive compound, kneading the resin composition precursor and the (C) polyolefin resin. And a second kneading step. A method for producing a resin composition is disclosed.

JP 2008-88358 A JP 2009-155517 A International Publication No. 2009/078376 Pamphlet JP 2009-155644 A

Conventionally, when a resin composition is prepared by using an aliphatic polyester resin, a propylene-based polymer, and further a plant fiber to produce a molded body, there has been a problem that it is inferior in rigidity and heat resistance. The present inventors have found that a molded article having excellent rigidity and heat resistance can be obtained by making the resin composition have the following constitution, and have completed the present invention.
An object of this invention is to provide the resin composition which can manufacture the molded object which has the outstanding rigidity and heat resistance.

The above-described problems of the present invention have been solved by the following means.
That is, the present invention relates to an aliphatic polyester polymer (A) 1 to 58% by weight, an elastomer (B) 0.5 to 50% by weight, and an epoxy polymer-containing ethylene polymer (C) 0.5. -50 wt%, propylene polymer (D) 10-58 wt%, plant fiber (E) 1-50 wt%, and modified propylene polymer (F) 1-50 wt% (However, the aliphatic polyester-based polymer (A), elastomers (B), epoxy-containing ethylene polymer (C), propylene-based polymer (D), plant fiber) (E) and the modified propylene polymer (F) are 100% by weight in total).

  ADVANTAGE OF THE INVENTION According to this invention, it becomes possible to provide the resin composition which can manufacture the molded object which has the outstanding rigidity and heat resistance.

(Resin composition)
The resin composition according to the present invention comprises an aliphatic polyester polymer (A) 1 to 58% by weight, an elastomer (B) 0.5 to 50% by weight, and an ethylene polymer (C ) 0.5 to 50% by weight, propylene polymer (D) 10 to 58% by weight, vegetable fiber (E) 1 to 50% by weight, modified propylene polymer (F) 1 to 50% by weight (However, the aliphatic polyester-based polymer (A), elastomers (B), epoxy-containing ethylene polymer (C), propylene-based polymer (D), plant, (The total weight of the fiber (E) and the modified propylene polymer (F) is 100% by weight).

In the resin composition according to the present invention, the propylene polymer (D) forms a continuous phase, and the aliphatic polyester polymer (A) is stably finely dispersed in the continuous phase of the propylene polymer (D). It is preferable. Further, the plant fiber (E) may be present in either the continuous phase or the dispersed phase, but it is preferable that the plant fiber is present in a dispersed state without agglomeration between the plant fibers. More preferably, it is dispersed in the coalescence (D).
Hereinafter, each component represented by the above (A) or the like is also simply referred to as “component (A)” or the like. In the present invention, the description of “lower limit to upper limit” representing a numerical range represents “more than the lower limit and less than or equal to the upper limit”, and the description of “upper limit to lower limit” represents “the upper limit or less and less than the lower limit”. That is, it represents a numerical range including an upper limit and a lower limit.
Hereinafter, each component will be described.

[Aliphatic polyester polymer (A)]
Examples of the aliphatic polyester polymer (A) include polyester polymers composed of hydroxycarboxylic acid or lactone, polycondensates of diol and dicarboxylic acid, and copolymers thereof. When the aliphatic polyester polymer (A) is a copolymer, the arrangement of the copolymer may be any of random copolymer, alternating copolymer, block copolymer, graft copolymer and the like. In addition, at least a part of these were cross-linked with a polyvalent isocyanate such as xylylene diisocyanate or 2,4-tolylene diisocyanate, or a cross-linking agent such as a polysaccharide such as cellulose, acetyl cellulose, or ethyl cellulose. It may be a thing. Furthermore, these may have any structure such as linear, cyclic, branched, star-shaped, and three-dimensional network structure, and there is no limitation, and a copolymer with a polyolefin resin or polyolefin It may be a graft polymer with a resin. Moreover, this component (A) can be used individually or in combination.

  Examples of the hydroxycarboxylic acid include hydroxycarboxylic acids having 2 to 18 carbon atoms, preferably 6 or less carbon atoms, and most preferably hydroxycarboxylic acids having 3 carbon atoms. Specifically, glycolic acid, L-lactic acid, D-lactic acid, D, L-lactic acid, 3-hydroxybutyrate, 3-hydroxyvalerate, 3-hydroxypropionate, 4-hydroxybutyrate, 4-hydroxy Valerate, 5-hydroxyvalerate, 3-hydroxypentenoate, 3-hydroxyhexanoate, 3-hydroxyheptanoate, 3-hydroxyoctanoate, 3-hydroxynonanoate, 3-hydroxydecanoate, etc. Is mentioned. Examples of the lactone include propiolactone, butyrolactone, valerolactone, caprolactone, and laurolactone.

  In the polyester polymer, the polycondensation diol is preferably a diol having 2 to 10 carbon atoms. Among these, an aliphatic diol having 2 to 4 carbon atoms or an alicyclic diol having 5 to 6 carbon atoms is more preferable. Specifically, ethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,2-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,8-octanediol, 1,10-decanediol, 1,12-dodecanediol, 1,14-tetradecanediol, 1,16-hexadecanediol, 1,18-octadecanediol, 1,2-cyclohexanediol, 1,4-cyclohexanediol, 1 , 2-cyclohexanedimethylol, 1,4-cyclohexanedimethylol and the like.

  In the polyester polymer, the dicarboxylic acid to be polycondensed is preferably an aliphatic dicarboxylic acid having 2 to 12 carbon atoms. Among these, an aliphatic dicarboxylic acid having 2 to 6 carbon atoms or an alicyclic dicarboxylic acid having 5 to 6 carbon atoms is more preferable. Specifically, succinic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, undecanedioic acid, dodecanedioic acid, 1,14-tetradecanedicarboxylic acid, 1,16 -Hexadecanedicarboxylic acid, 1,18-octadecanedicarboxylic acid, dimer acid and hydrogenated product thereof, hexahydrophthalic acid, hexahydroisophthalic acid, hexahydroterephthalic acid and the like. These dicarboxylic acids may be derivatives such as alkyl esters having 1 to 4 carbon atoms and acid anhydrides.

  Among the above aliphatic polyester polymers, polylactic acid, polybutylene succinate, poly (butylene succinate-co-butylene adipate), poly (butylene adipate-co-butylene terephthalate), polycaprolactone, poly (3-hydroxybutyrate) Rate), poly (3-hydroxybutyrate-co-3-hydroxyhexanoate), and polyglycolic acid are preferably used. When polylactic acid is used as the aliphatic polyester polymer (A), it is preferable that the polylactic acid has an L-form ratio of 94 mol% or more in the lactic acid component constituting the polylactic acid. By making the ratio of the L isomer within such a range, it is possible to prevent the melting point from being lowered.

  The weight average molecular weight of the aliphatic polyester polymer (A) is preferably 10,000 to 500,000, and more preferably 50,000 to 400,000. More preferably, it is 70,000 to 300,000. By setting the weight average molecular weight to 10,000 or more, a molded article excellent in impact strength and tensile elongation can be obtained. Moreover, the dispersibility of an aliphatic polyester-type polymer (A) becomes favorable by making a weight average molecular weight into 500,000 or less. The polylactic acid as the aliphatic polyester polymer (A) preferably has a molecular weight of 60,000 or more. In the present invention, the weight average molecular weight (Mw) is a value measured by GPC using standard polystyrene as a molecular weight standard substance.

The method for synthesizing the aliphatic polyester polymer (A) is not particularly limited. For example, the polylactic acid synthesis method includes a direct polycondensation method from lactic acid and a ring-opening polymerization method via lactide.
Polyethylene succinate and polybutylene succinate can be produced, for example, by the method described in JP-A-6-271656. In this method, (anhydrous) succinic acid and ethylene glycol (or 1,4-butanediol) are transesterified to obtain an oligomer, and then the obtained oligomer is polycondensed. In addition, as described in JP-A-4-189822 and JP-A-5-287068, a diisocyanate or a tetracarboxylic dianhydride is crosslinked when producing polyethylene succinate and polybutylene succinate. It may be used as an agent.
Polycaprolactone can be obtained by reacting ε-caprolactone with a diol such as ethylene glycol or diethylene glycol in the presence of a catalyst. Examples of the catalyst used in this reaction include organic tin compounds, organic titanium compounds, and organic tin halide compounds. Polycaprolactone can be obtained by adding these catalysts in an amount of 0.1 ppm to 5,000 ppm and polymerizing the monomer at 100 ° C. to 230 ° C., preferably in an inert gas. These production methods include, for example, Japanese Patent Publication No. 35-189, Japanese Patent Publication No. 35-497, Japanese Patent Publication No. 40-23917, Japanese Patent Publication No. 40-26557, Japanese Patent Publication No. 43-2473, Japanese Patent Publication No. 47-14739, Japanese Patent Publication No. This is disclosed in Japanese Laid-Open Patent Publication Nos. 56-49720 and 58-61119.
Among these production methods, those produced from plant-derived materials are preferably used.

  The melt flow rate (MFR) of the aliphatic polyester polymer (A) at 230 ° C. and a load of 21.2 N is not particularly limited, but is preferably 0.5 g / 10 min to 150 g / 10 min. / 10 minutes to 100 g / 10 minutes is more preferable, and 10 g / 10 minutes to 70 g / 10 minutes is most preferable.

[Elastomers (B)]
The elastomers (B) mean rubbery elastic bodies. The elastomers (B) include a rubber having a crosslinking point in the molecule and a thermoplastic elastomer in which the molecules are constrained by a molecular group of hard layers in the molecule.
As the elastomer (B), components other than the component (A) and the component (D) are used. For example, natural rubber, polybutadiene rubber, polyisoprene rubber, butyl rubber, amorphous or low crystalline ethylene elastomer, butadiene-styrene elastomer, butadiene-acrylonitrile elastomer, hydrogenated or non-hydrogenated styrene-conjugated diene block elastomer Polyester rubber, acrylic rubber, silicon rubber and the like. The elastomer is preferably an amorphous or low crystalline ethylene-based elastomer.

The ethylene-based elastomer is an elastomer containing a monomer unit derived from ethylene as a main component, for example, an ethylene homopolymer, an ethylene-α-olefin copolymer, an ethylene-ethylenically unsaturated ester copolymer. Etc.
Such an ethylene-based polymer is preferably an ethylene-α-olefin copolymer that is a copolymer of ethylene and one or more α-olefins. The α-olefin is preferably an α-olefin having 4 to 12 carbon atoms. Specifically, for example, 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, 1-nonene, 1-decene, 1-dodecene, 4-methyl-1-pentene, 4-methyl Examples include -1-hexene, vinylcyclohexane, vinylcyclohexene, styrene, norbornene, butadiene, and isoprene.

  Examples of hydrogenated or non-hydrogenated styrene-conjugated diene block elastomers include styrene-isoprene copolymers, styrene-isoprene-styrene copolymers, styrene-ethylenebutene-styrene copolymers, styrene-butadiene copolymers, Examples thereof include styrene-butadiene-styrene copolymers.

The density of the ethylene-based elastomer, from the viewpoint of the mechanical strength of the resulting molded article, preferably ^{850kg / m 3 ~910kg / m 3} . More preferably from ^{855kg / m 3 ~900kg / m 3} . For example, in the case of the density of the ethylene-α-olefin copolymer, it is preferably 850 kg / m ³ or more, and preferably 910 kg / m ³ or less from the viewpoint of impact strength and tensile elongation at break of the resulting resin composition. . More preferably from ^{855kg / m 3 ~900kg / m 3} . The density here is measured without annealing by a method defined in JIS K 6760-1981.

The MFR of the ethylene-based elastomer is preferably 0.05 g / 10 min to 100 g / 10 min from the viewpoint of the mechanical strength of the obtained molded product. More preferably, it is 0.1 g / 10min-50g / 10min, More preferably, it is 0.5g / 10min-40g / 10min.
MFR here is measured under the conditions of a test load of 21.2 N and a test temperature of 190 ° C. by the method defined in JIS K 7210 (1995).

  The melting temperature of the ethylene-based elastomer is preferably 110 ° C. or less, more preferably 100 ° C. or less, from the viewpoint of the mechanical strength of the obtained molded body. The heat of fusion of the ethylene-based elastomer is preferably 110 J / g or less, more preferably 100 J / g or less, from the viewpoint of the tensile elongation at break of the resin composition obtained. For example, the melting temperature of the ethylene-α-olefin copolymer is 110 ° C. or lower, more preferably 100 ° C. or lower. The amount of heat of fusion of the ethylene-α-olefin copolymer is preferably 110 J / g or less, more preferably 100 J / g or less.

As a method for producing the ethylene elastomer, a known polymerization method using a known olefin polymerization catalyst is used.
For example, an ethylene-α-olefin copolymer is a solution polymerization method, a slurry polymerization method, a high pressure ion polymerization method, a gas phase polymerization method using a Ziegler-Natta catalyst, a complex catalyst such as a metallocene complex or a nonmetallocene complex, Moreover, it is preferable to manufacture by the block polymerization method using a radical initiator, the solution polymerization method, etc. Among them, it is preferable to use a polymerization method using a Ziegler-Natta catalyst or a complex catalyst, and it is preferable to use a polymerization method in the presence of a metallocene catalyst.

[Ethylene polymer containing epoxy group (C)]
The ethylene-based polymer (C) containing an epoxy group used in the present invention is a copolymer containing a monomer unit derived from a monomer containing an epoxy group and a monomer unit derived from ethylene. It is a coalescence. This copolymer may further contain a monomer unit derived from an α-olefin not containing an epoxy group and a vinyl monomer unit not containing an epoxy group.
Examples of the monomer containing an epoxy group include α, β-unsaturated glycidyl ethers such as α, β-unsaturated glycidyl esters such as glycidyl methacrylate and glycidyl acrylate, allyl glycidyl ether, and 2-methylallyl glycidyl ether. Preferably, it is glycidyl methacrylate.
Examples of vinyl monomers not containing an epoxy group include unsaturated carboxylic acid esters such as methyl acrylate, ethyl acrylate, methyl methacrylate, and butyl acrylate; unsaturated vinyl esters such as vinyl acetate and vinyl propionate. Styrene; acrylonitrile; conjugated dienes and the like.
As a copolymer containing a monomer unit derived from a monomer containing an epoxy group and a monomer unit derived from ethylene, specifically, for example, a glycidyl methacrylate-ethylene copolymer (for example, Sumitomo Chemical product name Bond First).
Examples of the copolymer of ethylene, an epoxy group-containing monomer, and an α-olefin monomer that does not contain an epoxy group include glycidyl methacrylate-ethylene-propylene-butene copolymer.
Examples of copolymers of ethylene, a monomer containing an epoxy group, and a vinyl monomer not containing an epoxy group include glycidyl methacrylate-ethylene-styrene copolymer and glycidyl methacrylate-ethylene-acrylonitrile-styrene copolymer. Etc.
Copolymers of an epoxy group-containing monomer, ethylene, an α-olefin not containing an epoxy group, and a vinyl monomer not containing an epoxy group are polyethylene, ethylene-α-olefin copolymers. It may be a graft polymer obtained by graft polymerization of a monomer containing the above epoxy group to a polymer, a hydrogenated or non-hydrogenated styrene-conjugated diene copolymer, or the like.

  In the ethylene polymer (C) containing an epoxy group, the content of the monomer unit derived from the monomer containing the epoxy group is preferably 0.01 to 30% by weight, more preferably. Is 0.1 to 25% by weight, more preferably 1 to 20% by weight. However, the content of all monomer units in the ethylene-based polymer containing an epoxy group is 100% by weight. In addition, content of the monomer unit derived from the monomer containing an epoxy group is measured by an infrared method.

  The melt flow rate (MFR) of the ethylene-based polymer (C) containing an epoxy group is preferably 0.1 g / 10 min to 300 g / 10 min, more preferably 0.3 g / 10 min to 80 g / 10. Min, more preferably 0.5 g / 10 min to 20 g / 10 min. The melt flow rate here is measured under the conditions of a test load of 21.2 N and a test temperature of 190 ° C. by the method defined in JIS K 7210 (1995).

  As a method for producing an ethylene-based polymer (C) containing an epoxy group, for example, by a high-pressure radical polymerization method, a solution polymerization method, an emulsion polymerization method, etc., a monomer having an epoxy group, ethylene, and as necessary Examples thereof include a method of copolymerizing with other monomers and a method of graft-polymerizing a monomer having an epoxy group to an ethylene resin.

[Propylene polymer (D)]
The propylene polymer (D) used in the present invention is a propylene homopolymer or a copolymer having a propylene unit content of 50% by weight or more, a propylene-ethylene random copolymer, a propylene-α-olefin. A random copolymer, a propylene-ethylene-α-olefin copolymer, “a copolymer component mainly composed of propylene or a propylene homopolymer component (hereinafter also referred to as polymer component (I))”, and “propylene. And a copolymer component of ethylene and / or one or more comonomers selected from the group consisting of α-olefins having 4 or more carbon atoms (hereinafter also referred to as copolymer component (II)). Examples include coalescence.

Specific examples of the α-olefin constituting the propylene polymer (D) include 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene and 1-decene. Carbon number of the alpha olefin which comprises a propylene polymer (D) becomes like this. Preferably it is 4-20, More preferably, it is 4-12.
Examples of the propylene-α-olefin random copolymer include a propylene-1-butene random copolymer and a propylene-1-hexene random copolymer. Examples of the propylene-ethylene-α-olefin copolymer include a propylene-ethylene-1-butene copolymer and a propylene-ethylene-1-hexene copolymer.

In the copolymer composed of the polymer component (I) and the copolymer component (II), examples of the “copolymer component mainly composed of propylene” as the polymer component (I) include propylene -An ethylene copolymer component, a propylene-1-butene copolymer component, and a propylene-1-hexene copolymer component are mentioned. When the polymer component (I) is “a copolymer component mainly composed of propylene”, the content of the copolymer (that is, a monomer other than propylene) is less than 10% by weight. The polymer component (I) is preferably a propylene homopolymer.
Examples of the copolymer component (II) include a propylene-ethylene copolymer component, a propylene-ethylene-1-butene copolymer component, a propylene-ethylene-1-hexene copolymer component, and propylene-1. -Butene copolymer component and propylene-1-hexene copolymer component. In addition, content of the copolymer (namely, monomer other than propylene) in the said copolymer component (II) is 10 weight%-70 weight%.

  Examples of the copolymer composed of the polymer component (I) and the copolymer component (II) include (propylene)-(propylene-ethylene) copolymer and (propylene)-(propylene-ethylene-). 1-butene) copolymer, (propylene)-(propylene-ethylene-1-hexene) copolymer, (propylene)-(propylene-1-butene) copolymer, (propylene)-(propylene-1-hexene) ) Copolymer, (propylene-ethylene)-(propylene-ethylene) copolymer, (propylene-ethylene)-(propylene-ethylene-1-butene) copolymer, (propylene-ethylene)-(propylene-ethylene-) 1-hexene) copolymer, (propylene-ethylene)-(propylene-1-butene) copolymer, (propylene-ethylene)-( (Lopylene-1-hexene) copolymer, (propylene-1-butene)-(propylene-ethylene) copolymer, (propylene-1-butene)-(propylene-ethylene-1-butene) copolymer, (propylene -1-butene)-(propylene-ethylene-1-hexene) copolymer, (propylene-1-butene)-(propylene-1-butene) copolymer, and (propylene-1-butene)-(propylene- 1-hexene) copolymers.

  The propylene polymer (D) is a propylene homopolymer, a propylene-ethylene random copolymer, a propylene-1-butene random copolymer, a propylene-ethylene-1-butene copolymer, or (propylene)-(propylene -An ethylene) copolymer is preferable.

The isotactic pentad fraction measured by ¹³ C-NMR of the propylene polymer (D) is preferably 0.95 or more, more preferably 0.97 or more.

Here, the isotactic pentad fraction means A.I. The method described in Macromolecules, 6, 925 (1973) by Zambelli et al., Ie isotactic linkage in the pentad unit in the propylene polymer molecular chain measured by ¹³ C-NMR, in other words propylene monomer unit Is the fraction of propylene monomer units in the center of a chain of five consecutive meso-bonded chains. Specifically, the ratio of the mmmm peak area to the absorption peak area of the methyl carbon region measured by ¹³ C-NMR spectrum is the isotactic pentad fraction.

Propylene polymer (D) can be produced by homopolymerization using Ziegler-Natta type catalyst or metallocene catalyst, or copolymerization of propylene with one or more olefins selected from olefins other than propylene. And the like. The Ziegler-Natta type catalyst includes a catalyst system using a combination of a titanium-containing solid transition metal component and an organometallic component. Examples of the metallocene catalyst include a catalyst system using a combination of a transition metal compound of Group 4 to Group 6 having at least one cyclopentadienyl skeleton and a promoter component.
Examples of the polymerization method include a slurry polymerization method and a solution polymerization method performed in an inert hydrocarbon solvent, a liquid phase polymerization method and a gas phase polymerization method performed in the absence of a solvent, and continuously. Examples thereof include a gas phase-gas phase polymerization method and a liquid phase-gas phase polymerization method, and these polymerization methods may be a batch method or a continuous method. Moreover, the method of manufacturing a propylene polymer (D) in one step may be sufficient, and the method of manufacturing in multiple steps of two steps or more may be sufficient.
In particular, as a method for producing a copolymer comprising the polymer component (I) and the copolymer component (II), preferably, the step of producing the polymer component (I) and the copolymer component ( II) is a multi-stage production method having at least two steps.

  The melt flow rate of the propylene polymer (D) is preferably 0.05 g / 10 min to 200 g / 10 min, more preferably 1 g / 10 min to 180 g / 10 min, and 10 g / 10 min. More preferably, it is ˜150 g / 10 min. In addition, the melt flow rate of polypropylene resin (D) is the value measured by 230 degreeC and a 21.2N load according to JISK7210.

[Plant fiber (E)]
The plant fiber (E) is not particularly limited as long as it is a plant-derived fiber material. Specific examples include cotton fiber, hemp fiber, bamboo fiber, wood fiber, kenaf fiber, hemp fiber, jute fiber, banana fiber, and coconut. Examples thereof include plant fibers such as fibers, pulps and cellulose fibers processed from these plant fibers, and among these, kenaf fibers are preferable.

  The average fiber length of the plant fiber (E) is preferably 0.01 to 20 mm, more preferably 0.1 to 10 mm. When the plant fiber (E) having an average fiber length in the above range is used, the reinforcing effect by the fiber is further enhanced, and a molded product having excellent rigidity and heat resistance can be obtained.

  In particular, when kenaf fibers are used as plant fibers, it is preferable to use kenaf fibers from which crushed pieces having a fiber length of 50 μm or less are removed. The water content of the kenaf fiber is preferably 5% by weight or less, and more preferably 1% by weight or less based on the weight of the kenaf fiber. When the moisture content is in the above range, it is possible to produce a molded article having excellent appearance and excellent rigidity and heat resistance. In order to remove moisture from the kenaf fiber, the kenaf fiber is preferably dried at 30 to 200 ° C., more preferably 80 to 150 ° C. before melt kneading.

[Modified propylene polymer (F)]
The modified propylene polymer (F) is a silane-modified propylene polymer (F-1) or a modified propylene polymer (F-2) obtained by grafting an α, β-glycidyl ester. Preferably, it is a silane modified propylene polymer (F-1).

<Silane-modified propylene polymer (F-1)>
The silane-modified propylene polymer (F-1) has a structure derived from a propylene polymer and has an alkoxysilane residue as a functional group.
Here, the propylene polymer has the same meaning as the propylene polymer (D).

The alkoxysilane residue has a general formula: —SiX ₃ [wherein X may be the same or different, and each represents an alkoxy group (preferably an alkoxy group having 1 to 4 carbon atoms). ] Is preferable. Such a silane-modified olefin polymer may be one in which the alkoxysilane residue is bonded to the above-mentioned propylene polymer, and the bonding site may be a molecular chain even at the terminal of the propylene polymer. It may be in the middle. The production method of such a silane-modified propylene polymer (F-1) is not particularly limited. For example, the silane coupling agent having an alkoxysilane residue is reacted with the propylene polymer to improve the silane-modified propylene polymer (F-1). Examples include silane cross-linkable ones.

  The molecular weight (weight average molecular weight) of the silane-modified propylene polymer according to the present invention is preferably about 5,000 to 1,000,000. When the molecular weight is not less than the above lower limit, the strength of the resulting molded product is excellent, and when it is not more than the above upper limit, the kneaded product has excellent fluidity and uniform dispersibility when melt-kneaded.

  The melt flow rate of the silane-modified propylene polymer (F-1) is preferably 0.3 g / 10 min to 300 g / 10 min, more preferably 1 g / 10 min to 150 g / 10 min. More preferably, it is 3 g / 10 minutes to 70 g / 10 minutes. The melt flow rate of the silane-modified propylene polymer (F-1) is a value measured at 230 ° C. and 21.2 N load according to JIS K 7210.

  The flexural modulus (FM) of the silane-modified propylene polymer (F-1) is preferably 300 MPa to 5,000 MPa, and preferably 700 MPa to 3,000 MPa from the viewpoint of the flexural modulus and heat resistance. More preferably, it is 1,100 MPa to 2,000 MPa. Here, the flexural modulus of the silane-modified propylene polymer (F-1) is a value measured according to JIS K 7171.

<Modified propylene polymer (F-2) formed by grafting α, β-glycidyl ester>
The modified propylene polymer (F-2) obtained by grafting α, β-glycidyl ester (hereinafter also referred to as modified propylene polymer (F-2)) is derived from α, β-unsaturated glycidyl ester. It is preferable that the polymer is formed by grafting an α, β-unsaturated glycidyl ester having a structural unit content of 0.1 wt% or more and 1.0 wt% or less. That is, a polymer obtained by graft polymerization of a predetermined amount of α, β-unsaturated glycidyl ester to a propylene-based polymer is preferable.
Examples of the α, β-unsaturated glycidyl ester include glycidyl methacrylate and glycidyl acrylate. Of these, glycidyl methacrylate is preferred.

  The content of the structural unit derived from the α, β-unsaturated glycidyl ester contained in the modified propylene polymer (F-2) is preferably 0.1% by weight or more, more preferably 0. 5 wt% or more and less than 1.0 wt%. However, the content of the structural unit in the modified propylene polymer (F-2) is 100% by weight. In addition, the content of the structural unit derived from the α, β-unsaturated glycidyl ester is measured by an infrared method.

  The melt flow rate (MFR) of the modified propylene polymer (F-2) is preferably 0.1 g / 10 min to 300 g / 10 min, more preferably 0.5 g / 10 min to 150 g / 10 min. More preferably, it is 1 g / 10 min to 40 g / min. Here, the melt flow rate is a value measured under conditions of a test temperature of 230 ° C. and a test load of 21.2 N according to JIS K 7210 (1995).

Examples of the method for producing the modified propylene polymer (F-2) include a method in which a propylene polymer and an α, β-unsaturated glycidyl ester are melt-kneaded using a mixer or an extruder. It is done.
In addition, as a propylene polymer used for manufacture of a modified polypropylene polymer, the polymer which can be used as said propylene polymer (D) is mentioned, The detail is as above-mentioned.

[Resin composition]
The resin composition according to the present invention contains components (A) to (F).
The content of each component is preferably 1 to 58% by weight of the aliphatic polyester polymer (A), and preferably 5% by weight or more, more preferably from the viewpoint of increasing the flexural modulus of the molded product. 10% by weight or more. Moreover, from a viewpoint of making the heat resistance of a molded object higher, Preferably it is 45 weight% or less, More preferably, it is 30 weight% or less.
The content of the elastomers (B) is 0.5 to 50% by weight, and is preferably 1% by weight or more, more preferably 2% by weight or more from the viewpoint of increasing the impact strength of the molded body. preferable. Further, from the viewpoint of increasing the flexural modulus and heat resistance of the molded body, it is preferably 30% by weight or less, and more preferably 20% by weight or less.
The content of the ethylene polymer (C) containing an epoxy group is 0.5 to 50% by weight, 1% by weight from the viewpoint of enhancing the dispersibility of the component (A) and increasing the impact strength of the molded product. The above is preferable. Further, from the viewpoint of increasing the flexural modulus and heat resistance of the molded body, it is preferably 20% by weight or less, and more preferably 10% by weight or less.
The content of the propylene-based polymer (D) is 10 to 58% by weight, and is preferably 20% by weight or more and more preferably 30% by weight or more from the viewpoint of further improving processability and heat resistance. More preferred. Further, from the viewpoint of further increasing the impact strength of the molded article, it is preferably 55% by weight or less, and more preferably 50% by weight or less.
The content of the plant fiber (E) is 1 to 50% by weight, preferably 3% by weight or more from the viewpoint of enhancing the bending elastic modulus and heat resistance of the molded body, and is 5% by weight or more. Is more preferable. Further, from the viewpoint of enhancing the impact resistance of the molded body and making it difficult to cause delamination on the surface of the molded body, it is preferably 30% by weight or less, and more preferably 20% by weight or less.
The content of the modified propylene polymer (F) is 1 to 50% by weight, and preferably 1.5% by weight or more from the viewpoint of enhancing the flexural modulus and heat resistance of the molded body. % Or more is more preferable. Moreover, from a viewpoint of improving workability and the external appearance of a molded object, it is preferable that it is 30 weight% or less, and it is more preferable that it is 20 weight% or less.
In addition, aliphatic polyester polymer (A), elastomers (B), ethylene polymer (C) containing an epoxy group, propylene polymer (D), vegetable fiber (E), and modified propylene polymer The total weight of the polymer (F) is 100% by weight.
Further, from the viewpoint that the component (D) preferably forms a continuous phase, the content (volume) of the component (D) is preferably larger than the content (volume) of the component (A).
Two or more components (A) to (F) may be used in combination, and in that case, the total content is within the above range.

The bending elastic modulus at 23 ° C. when the resin composition according to the present invention is an injection-molded body is preferably 1,250 MPa or more, more preferably 1,500 MPa or more, from the viewpoint of product rigidity. Preferably, it is 1,500 MPa to 1,800 MPa.
The deflection temperature under load when the resin composition according to the present invention is formed into a molded body (load of 0.45 MPa, conforming to JIS K 7191-2) is preferably 70 ° C. or more from the viewpoint of heat resistance of the product, More preferably, it is 90 ° C. or higher.
Izod impact strength when the resin composition of the present invention was molded bodies (23 ° C., notched) is preferably at 3 kJ / m ² or more, more preferably 7 kJ / m ² or more.
When the resin composition according to the present invention is formed into a molded body, peeling may occur due to rubbing with other objects during use, and the appearance may be impaired, particularly easily in the vicinity of the gate portion of the molded body. Therefore, it is preferable that delamination does not occur on the surface of the molded body.

  The melt flow rate (230 ° C., 2.16 kgf load, conforming to JIS K 7210) of the entire resin composition according to the present invention is preferably 1 g / 10 min or more from the viewpoint of molding processability, and more preferably, It is 3 g / 10 min or more, and from the viewpoint of impact resistance of the molded article, it is preferably 100 g / 10 min or less, and more preferably 50 g / 10 min or less.

  The resin composition of the present invention can be obtained by melt-kneading each raw material component at 150 ° C or higher, more preferably 160 to 300 ° C, and still more preferably 170 to 260 ° C. For melt kneading, for example, a Banbury mixer, a single-screw extruder, a twin-screw co-rotating extruder, or the like can be used.

  Examples of the shape of the resin composition include a strand shape, a sheet shape, a flat plate shape, and a pellet shape obtained by cutting a strand into an appropriate length. In order to mold the resin composition of the present invention, the shape is preferably a pellet having a length of 1 to 50 mm from the viewpoint of production stability of the obtained molded body.

As a manufacturing method of the resin composition which concerns on this invention, the method of melt-kneading a component (A)-a component (F) is mentioned. The kneading order of the raw material components is not particularly limited, but it is preferable to blend and knead by the following method.
That is, as a method for producing a resin composition, a propylene polymer (D), a plant fiber (E), and a modified propylene polymer (F) are kneaded to obtain a resin composition precursor (G). A first kneading step to be produced, an aliphatic polyester polymer (A), an elastomer (B), and an ethylene polymer (C) containing an epoxy group are kneaded to obtain a resin composition precursor ( A second kneading step for producing H), the resin composition precursor (G) produced in the first kneading step, and the resin composition precursor (H) produced in the second kneading step. It is preferable to have a third kneading step for kneading.
In the second kneading step and the third kneading step, a propylene polymer (D) may be further added as necessary. For example, in the third kneading step, the resin composition precursor (G), the resin composition precursor (H), and the propylene-based polymer (D) may be kneaded.
It is considered that the dispersibility of the plant fiber (E) in the propylene polymer (D) can be improved by kneading the component (D), the component (E) and the component (F) in the first kneading step. It is done. Further, in the second kneading step, the dispersibility of the aliphatic polyester polymer (A) in the propylene polymer (D) can be improved by kneading the component (A), the component (B) and the component (C). It can be increased.

The propylene polymer (D) is added in the first kneading step, the second kneading step, and, if necessary, in the third kneading step, but the total amount added in the first kneading step to the third kneading step is totaled. And it should just be 10-58 weight% with respect to the total amount of the six components of a component (A)-a component (F).
Further, the amount of the propylene-based polymer (D) added in the first kneading step is not particularly limited, but from the viewpoint that it is preferable to form a continuous phase in the resin composition precursor (G), the component (A) -It is preferable to make it into a maximum component on a volume basis among (D).

  The kneading temperature is not particularly limited, but the kneading temperature in the first kneading step and the third kneading step is preferably 150 ° C. or higher, more preferably 160 to 240 ° C., and further preferably 170 to 220 ° C. By setting it as this temperature range, deterioration of a vegetable fiber (E) is suppressed and stable kneading | mixing is attained. The kneading temperature in the second kneading step is preferably 150 ° C. or higher, more preferably 160 to 300 ° C., and further preferably 170 to 260 ° C. By setting this temperature range, the component (A) can be stably finely dispersed in the continuous phase component (D).

The resin composition according to the present invention may contain a known additive. Examples of additives include neutralizers, antioxidants, ultraviolet absorbers, lubricants, antistatic agents, antiblocking agents, processing aids, organic peroxides, and colorants (inorganic pigments, organic pigments, pigment dispersions). Agents), foaming agents, foam nucleating agents, plasticizers, flame retardants, crosslinking agents, crosslinking aids, brightening agents, antibacterial agents, light diffusing agents, and the like. These additives may be used alone or in combination of two or more.
In addition, when the resin composition which concerns on this invention contains an additive, when the total amount of said component (A) -component (F) is 100 weight part, the total amount of an additive is 100 weight part or less. Preferably, the amount is 0.001 to 50 parts by weight, more preferably 0.01 to 20 parts by weight.

The molded body obtained by molding the resin composition according to the present invention is preferably an injection molded body produced by an injection molding method. Examples of the injection molding method include a general injection molding method, an injection foam molding method, a supercritical injection foam molding method, an ultrahigh speed injection molding method, an injection compression molding method, a gas assist injection molding method, a sandwich molding method, and a sandwich foaming method. Examples thereof include molding methods and insert / outsert molding methods.
Examples of the molded body include automobile materials, home appliance materials, containers, and the like. Among them, it is suitable for automobile interior because of its excellent flexural modulus and heat resistance.

  Hereinafter, the present invention will be described with reference to examples and comparative examples. The components used in Examples and Comparative Examples are shown below.

(1) Aliphatic polyester polymer (A)
・ Ingredient (A)
TE-2000C: Polylactic acid resin, manufactured by Unitika Ltd., Terramac TE-2000C, MFR (measured at 230 ° C.) = 40 g / 10 minutes

(2) Elastomers (B)
・ Ingredient (B)
EG8842: Ethylene-octene rubber, manufactured by DuPont Dow, Engage (registered trademark) EG8842, MFR (190 ° C.) = 1 g / 10 min, specific gravity (g / cm ³ ) = 0.858

(3) Ethylene polymer containing epoxy group (C)
-Component (C) (component (F) -4: for comparative example)
BF-E: ethylene-glycidyl methacrylate copolymer, manufactured by Sumitomo Chemical Co., Ltd., Bond First E, MFR (measured at 190 ° C.) = 3 g / 10 minutes, monomer unit content derived from glycidyl methacrylate = 12 weight %

(4) Propylene polymer (D)
・ Ingredient (D)
Propylene homopolymer content when the weight of the mixture of propylene homopolymer and ethylene-propylene copolymer, MFR (230 ° C.) = 50 g / 10 min) and component (D) is 100% by weight = 87.0 % By weight, ethylene-propylene copolymer content = 13.0% by weight, ethylene-propylene copolymer being 100% by weight of ethylene-propylene copolymer-based monomer units based on ethylene Content = 32% by weight

(5) Plant fiber (E)
・ Ingredient (E)
Kenaf: Unipa Ax, Kenaf core powder, particle size <10 μm

(6) Modified propylene polymer (F)
-Component (F) -1
XPM800HM: Polypropylene-based silane crosslinkable resin, manufactured by Mitsubishi Chemical Corporation, Linkron XPM800HM, MFR (measured at 230 ° C.) = 16 g / 10 min, D = 910, FM = 1,500 MPa
-Component (F) -2
GMA-PP: glycidyl methacrylate (GMA) modified polypropylene polymer, MFR (measured at 230 ° C.) = 9 g / 10 min, glycidyl methacrylate graft ratio = 0.6 wt%)
Component (F) -3: Comparative Example HM600A: Polyethylene-based silane crosslinkable resin, manufactured by Mitsubishi Chemical Corporation, Linkron HM600A, MFR (measured at 190 ° C.) = 9 g / 10 minutes, D = 955, FM = 1 , 000 MPa

The physical properties of the raw material components and the resin composition were measured according to the methods shown below.
(1) Melt flow rate (MFR, unit: g / 10 minutes)
The measurement was performed according to the method defined in JIS K 7210.
The measurement temperature was 230 ° C. or 190 ° C., and the load was 2.16 kg (21.2 N).

(2) Density (D, unit: kg / m ³ )
The measurement was performed according to the A method (underwater substitution method) defined in JIS K7112.

(3) Intrinsic viscosity number ([η], unit: dl / g)
Using a Ubbelohde viscometer, reduced viscosities were measured at three concentrations of 0.1, 0.2 and 0.5 g / dl. The intrinsic viscosity number was obtained by an extrapolation method in which the reduced viscosity was plotted against the concentration and the concentration was extrapolated to zero.

(4) Flexural modulus (unit: MPa)
It measured according to the method prescribed | regulated to JISK7171 (2008). A test piece molded by injection molding was used. The thickness of the test piece was 3.2 mm, the bending load speed was 2.0 mm / min, and the bending elastic modulus was evaluated. The measurement temperature was 23 ° C.

(5) Deflection temperature under load (HDT, unit: ° C)
The deflection temperature under load of the test piece (width 12.7 mm, thickness 6.4 mm) formed by injection molding was measured at a load of 0.45 MPa according to the method defined in JIS K 7191-2.

(6) Izod impact strength (Izod, unit: KJ / m ² )
Using a test piece (width 12.7 mm, thickness 3.2 mm) formed by injection molding, a measurement was made with a notch at a temperature of 23 ° C. according to the method defined in ASTM D648.

(7) Layer peeling The gate part of the load deflection temperature test piece was scratched with a cutter knife along the resin flow direction, and the surface layer was pulled using a nipper to evaluate whether peeling occurred.
The following judgment was performed according to the state of peeling.
A: No peeling observed B: Partial peeling observed C: Entire peeling observed

(Examples 1-3 and Comparative Examples 1-3)
The resin composition according to the present invention was produced by the following method.
In the first kneading step, using a twin-screw kneading extruder having a cylinder inner diameter of 50 mm (TEM 50A, manufactured by Toshiba Machine Co., Ltd.) having a plurality of raw material inlets, the mixing ratio shown in Table 1 from the raw material inlet on the most upstream side. The raw materials were charged and kneaded. The cylinder temperature was set at 190 ° C., and a resin composition precursor (G) was produced at an extrusion rate of 30 kg / hour and a screw rotation speed of 200 rpm.
In the second kneading step and the third kneading step, a twin-screw kneading extruder having a cylinder inner diameter of 50 mm (TEM 50A, manufactured by Toshiba Machine Co., Ltd.) having a plurality of raw material inlets is used, from the raw material inlet on the most upstream side. The raw materials of the second kneading step are charged at the mixing ratio shown in Table 1 and kneaded to prepare a resin composition precursor (H). Subsequently, the resin composition precursor (G) and components ( D) was added and kneaded with the resin composition precursor (H). The cylinder temperature was set to 190 ° C., and the resin composition was prepared by kneading at an extrusion rate of 50 kg / hr and a screw rotation speed of 200 rpm.

  Test pieces for evaluating physical properties were produced under the following injection molding conditions. The resin composition pellets obtained above were cooled using a Saicap 110/50 injection molding machine manufactured by Sumitomo Heavy Industries, Ltd., at a molding temperature of 200 ° C., a mold cooling temperature of 35 ° C., an injection time of 15 seconds, and cooling. Injection molding was performed in 30 seconds. The obtained injection molded article was measured for flexural modulus, deflection temperature under load, and Izod impact strength to evaluate delamination. The results are shown in Table 1.

Claims (4)

1 to 58% by weight of an aliphatic polyester polymer (A),
Elastomers (B) 0.5-50% by weight,
0.5 to 50% by weight of an ethylene polymer (C) containing an epoxy group;
10 to 58% by weight of the propylene polymer (D),
1 to 50% by weight of plant fiber (E),
Modified propylene polymer (F) 1-50% by weight of a resin composition (provided that the aliphatic polyester polymer (A), elastomers (B), epoxy group-containing ethylene polymer (C ), The total weight of the propylene polymer (D), the plant fiber (E) and the modified propylene polymer (F) is 100% by weight).   The resin composition according to claim 1, wherein in the resin composition, the modified propylene polymer (F) is a silane-modified propylene polymer. A first kneading step of kneading a propylene polymer (D), a vegetable fiber (E), and a modified propylene polymer (F) to produce a resin composition precursor (G);
Second kneading step for producing a resin composition precursor (H) by kneading an aliphatic polyester polymer (A), an elastomer (B), and an ethylene polymer (C) containing an epoxy group When,
A third kneading step of kneading the resin composition precursor (G) produced in the first kneading step and the resin composition precursor (H) produced in the second kneading step, The manufacturing method of the resin composition of Claim 1 or 2.   The molded object obtained by shape | molding the resin composition of Claim 1 or 2.