JP2018035320A - Polyolefin resin composition and method for producing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a polyolefin resin composition which can improve impact resistance using a material derived from a biomass in place of a petroleum-based resin/rubber, and to provide a method for producing the same.SOLUTION: A polyolefin resin composition is composed by dynamic crosslinking a resin mixture containing a polyolefin resin, trans-polyisoprene and a crosslinking agent. The polyolefin resin composition can further enhance its versatility in applications such as an automotive member and a member for home electronics requiring impact resistance.SELECTED DRAWING: None

Description

  The present invention relates to a polyolefin resin composition and a method for producing the same, and more particularly to a polyolefin resin composition having excellent impact resistance and a method for producing the same.

  Resins are used in various industrial products surrounding daily life such as daily necessities, automobile parts, and electrical appliances. Polyolefin resins are resins that are versatile and have excellent mechanical properties.

  For example, polypropylene resin is one of versatile resins among polyolefin resins. Examples of the type include homopolypropylene composed entirely of propylene repeating units, random polypropylene which is a copolymer with an ethylene monomer, and block polypropylene. Polypropylene resins have various properties depending on the type. For example, homopolypropylene has high rigidity but low impact resistance, and random polypropylene and block polypropylene have properties that are superior in impact resistance to homopolypropylene but inferior in rigidity.

  In recent years, polypropylene resin has been used as a structural material in applications such as a member for home appliances and a member for automobiles because of its excellent properties. And the improvement of the further impact resistance of the polypropylene resin in the said use is desired.

  In order to improve the impact resistance of such a polypropylene resin, for example, it is known that homopolypropylene is copolymerized with an ethylene monomer, and that other elastomer components such as resin and rubber are added to the polypropylene resin. Patent Document 1 proposes to improve impact resistance by crosslinking an elastomer component added to a polypropylene resin.

  However, it is difficult to say that the impact resistance of the obtained resin composition is still sufficient by any of these techniques. Similar impact resistance improvements are also desired for other polyolefin resins such as polyethylene resins. Also, most of the resin and rubber components used in the above technology are petroleum resins and rubbers such as synthetic resins, synthetic rubbers, and ethylene propylene rubber. From the viewpoint of environmental problems, development of impact resistance modifiers and modification methods for polyolefin resins using biopolymers is desired as an alternative technique.

JP 2011-195706 A

  The present invention has an object to solve the above-mentioned problems, and the object thereof is a polyolefin resin composition that can improve impact resistance by using a biomass-derived material in place of petroleum-based resin / rubber. And providing a manufacturing method thereof.

  The present invention is a polyolefin resin composition obtained by dynamically crosslinking a resin mixture containing a polyolefin resin, transpolyisoprene and a crosslinking agent.

  In one embodiment, when the content of the trans polyisoprene is 100 parts by mass, the content of the polyolefin resin is 80 parts by mass to 500 parts by mass, and the content of the crosslinking agent is 0.1 parts by mass. Part to 10 parts by mass.

  In one embodiment, when the content of the trans polyisoprene is 100 parts by mass, the content of the polyolefin resin is 100 parts by mass to 240 parts by mass, and the content of the crosslinking agent is 0.5 parts by mass. Part to 4.5 parts by mass.

  In one embodiment, the cross-linking agent is an organic peroxide.

  In a further embodiment, the organic peroxide is dicumyl peroxide, 2,5-dimethyl-2,5-di (t-butylperoxy) hexane, and 2,5-dimethyl-2,5- (t- (Butylperoxy) -3-hexyne is at least one organic peroxide selected from the group consisting of.

  In one embodiment, the trans polyisoprene has a group of particles having an average particle size of 0.1 μm to 100 μm or a structure in which the particles are imparted to each other, and the polyolefin resin composition has a sea-island structure or a co-continuous structure. Is forming.

  The present invention also provides a method for producing a polyolefin resin composition, comprising: mixing a polyolefin resin, transpolyisoprene, and a crosslinking agent to obtain a resin mixture; and heating and kneading the resin mixture to move the resin mixture. Cross-linking.

  In one embodiment, the kneading step is performed at a temperature of 80 ° C to 240 ° C.

  In one embodiment, when the content of the trans polyisoprene is 100 parts by mass, the content of the polyolefin resin is 80 parts by mass to 500 parts by mass, and the content of the crosslinking agent is 0.1 parts by mass. Part to 10 parts by mass.

  In one embodiment, the cross-linking agent is an organic peroxide.

  The present invention is also a resin molded article containing the polyolefin resin composition.

  According to the present invention, the impact resistance of the resin composition can be improved without adding a petroleum resin or rubber. Thereby, the polyolefin resin composition of this invention can further improve the versatility in the use for which impact resistance is required, such as a member for motor vehicles, a member for household appliances.

It is an electron micrograph which expanded the fracture surface of the observation sample produced from the strip piece produced for the Charpy impact test about the resin composition obtained in Example 1 and Comparative Example 2, Comprising: (a) is a comparative example 2 is an enlarged photograph (1000 times) of a fracture surface of an observation sample produced from the resin composition of No. 2, and (b) is an enlarged photograph (1000 times) of a fracture surface of an observation sample produced from the resin composition of Example 1. It is. 10 is a graph showing the results of a peel test for each of “test piece with DCP treatment” and “test piece without DCP treatment” produced in Example 7. FIG.

  Hereinafter, the present invention will be described in detail.

(Polyolefin resin composition)
The polyolefin resin composition of the present invention is constituted by dynamically crosslinking a resin mixture containing a polyolefin resin, transpolyisoprene and a crosslinking agent.

  The polyolefin resin constituting the resin composition of the present invention is a generic term for polyolefin-based resins, and examples thereof include polymers and copolymers containing olefins or alkenes (for example, α-olefins) as monomer units. Examples of such polyolefin resins include olefinic thermoplastics including polypropylene (PP) resin, polyethylene (PE) resin, polymethylpentene (PMP) resin, polypropylene as a hard segment, and ethylene propylene rubber as a soft segment. Elastomeric (TPO) resins, as well as combinations thereof, can be mentioned. Furthermore, examples of the polypropylene resin include a homopolymer (homopolypropylene) that is a homopolymer of propylene, and a random copolymer that includes a predetermined amount (for example, 4.5% by weight or less) of ethylene as a copolymer component with respect to propylene. Terpolymers containing ethylene and 1-butene as copolymerization components in propylene, block copolymers of ethylene and propylene, and combinations thereof. Examples of polyethylene resins include, for example, high density polyethylene (HDPE) low density polyethylene (LDPE), linear low density polyethylene (LLDPE), very low density polyethylene (VLDPE), ultra high molecular weight polyethylene (UHMW-PE), And ethylene vinyl acetate copolymer (EVA), and combinations thereof.

  The weight average molecular weight of the polyolefin resin in the present invention is preferably 10,000 to 1,000,000, more preferably 50,000 to 500,000. If the weight average molecular weight of the polyolefin resin is less than 10,000, the mechanical properties of the resulting polyolefin resin composition may be lowered, and the versatility as a resin molded product may be impaired. If the weight average molecular weight of the polyolefin resin exceeds 1,000,000, the moldability of the resulting polyolefin resin composition may be reduced.

  The content of the polyolefin resin in the resin composition of the present invention can be preferably set based on the content of trans polyisoprene described later. In the present invention, for example, when the content of transpolyisoprene is 100 parts by mass, the content of the polyolefin resin is preferably 80 parts by mass to 500 parts by mass, more preferably 90 parts by mass to 400 parts by mass, More preferably, it is 100 mass parts-240 mass parts. In the above criteria, if the content of the polyolefin resin is less than 80 parts by mass, the amount of the polyolefin resin contained in the resulting resin composition will be relatively lowered as compared with the amount of other components, There is a risk that the mechanical properties of the polyolefin resin itself may not be utilized. In the above criteria, if the content of the polyolefin resin exceeds 500 parts by mass, the content of transpolyisoprene contained in the obtained resin composition is relatively lowered as compared with the amount of other polyolefin constituents. Therefore, it may be difficult to impart sufficient impact resistance to the resulting resin composition.

  In the polyolefin resin composition of the present invention, the trans polyisoprene may be, for example, one derived from biomass, one chemically synthesized, or a combination thereof. In particular, trans polyisoprene is preferably polyisoprene obtained from biomass because it is a non-petroleum material and is easily available. The polyisoprene obtained from biomass includes trans polyisoprene and cis polyisoprene. In the present invention, the polyisoprene obtained from the material derived from the biomass includes, in addition to trans polyisoprene. In addition, cis polyisoprene may be contained within a range that does not affect the effect of the polyolefin resin composition that can be provided by the trans polyisoprene itself. Furthermore, in the present invention, trans polyisoprene may be appropriately chemically modified with a maleic anhydride group, a maleimide group, an epoxy group, or the like.

  Biomass containing polyisoprene includes, for example, plant tissues composed of plant roots, stems (stems), leaves, wings (pericarps and seeds), and bark, and combinations thereof. Examples of the plants constituting them include, but are not necessarily limited to, Eucommia ulmoides Oliver, Paraquim guttata, and Bala rubber (Mimusops balata). In the present invention, in addition to obtaining a trans polyisoprene having a high weight average molecular weight, the content of the trans 1,4-bond unit is high and the content of the bond isomer unit is low in the structure. Therefore, it is preferable to use trans polyisoprene derived from eucommia. Transpolyisoprene can be obtained by a known method in the art using, for example, a dried or non-dried pulverized plant tissue and / or cutting powder.

  The number average molecular weight (Mn) of trans polyisoprene in the present invention is not necessarily limited. For example, when the trans polyisoprene is derived from Eucommia, it is preferably 10,000 to 3,000,000, more preferably 50. 1,000 to 2,000,000, still more preferably 100,000 to 1,500,000.

Or although the weight average molecular weight (Mw) of the trans polyisoprene in this invention is not necessarily limited, For example, when it is a thing derived from a eucommia, Preferably it is 1 * 10 < ³ > -5 * 10 < ⁶ >, More preferably, it is 1 * 10 ^{4 to} 5 × 10 ⁶ .

  Further, in the resin composition of the present invention, the transpolyisoprene has a group of particles constituted by a predetermined size or a continuous fine structure, and the resin composition can form a sea-island structure or a co-continuous structure. . Here, the term “continuous microstructure” used in the present specification means that, for example, particles of the above-mentioned transpolyisoprene having a predetermined size are imparted to each other (for example, physical adhesion such as molten adhesion, bonding, adsorption, etc.). It refers to the structure formed by applying and including chemical and chemical application). The average particle size of trans polyisoprene having such particle morphology is preferably 0.1 μm to 100 μm, more preferably 0.1 μm to 10 μm. When the trans polyisoprene satisfies the above average particle diameter and the resin composition forms a phase structure, the polypropylene resin composition can be modified to further improve the impact resistance. In addition, the average particle diameter of such trans polyisoprene exists in the said cross section, for example by etching the cross section of the sample piece comprised from the obtained polyolefin resin composition with a solvent like n-hexane. The trans polyisoprene component is removed, and the resulting pores and phase structure (corresponding to the particle size and shape of the trans polyisoprene contained in the polyolefin resin composition) are used by a sputtering technique such as gold vapor deposition. The surface treatment can be performed, and then the radius of the pores subjected to the surface treatment can be measured through the viewing angle of the electron micrograph. Moreover, the phase structure in the resin composition can be observed through the operation using the electron microscope.

  In the polyolefin resin composition of the present invention, the crosslinking agent is blended with the polyolefin resin and trans polyisoprene as a resin mixture. By dynamically crosslinking such a resin mixture, it is possible to provide excellent physical properties (for example, impact resistance) to the resulting resin composition as compared to an uncrosslinked one.

  In the present invention, the crosslinking agent is, for example, an organic peroxide, and examples of the organic peroxide include 2,5-dimethyl-2,5-di (t-butylperoxy) hexane, dicumyl peroxide, And 2,5-dimethyl-2,5- (t-butylperoxy) -3-hexyne, and combinations thereof. For example, the organic peroxide has a decomposition temperature close to that of a polyolefin resin (for example, polypropylene resin); it is easily available as a reagent and a material for industrial production; It is useful as a crosslinking agent in the present invention.

  The content of the crosslinking agent in the resin composition of the present invention can be preferably set based on the content of the trans polyisoprene. In the present invention, for example, when the content of transpolyisoprene is 100 parts by mass, the content of the crosslinking agent is preferably 0.1 parts by mass to 10 parts by mass, more preferably 0.1 parts by mass to 7 parts by mass. 0.5 parts by mass, more preferably 0.5 parts by mass to 4.5 parts by mass. In the above criteria, if the content of the crosslinking agent is less than 0.1 parts by mass, it is difficult to perform appropriate dynamic crosslinking in the obtained resin composition, and satisfactory impact resistance is provided. There is a risk that it will not be obtained. In the above criteria, when the content of the crosslinking agent exceeds 10 parts by mass, the dynamic crosslinking formed in the resulting resin composition becomes a so-called hypercrosslinking and firmly restrains each constituent molecule, and the resin composition There is a risk of deteriorating the molding processability of the object itself.

  The polyolefin resin composition of the present invention may further contain other additive materials as necessary. Examples of other additive materials include fillers, crystal nucleating agents, plasticizers, vulcanization accelerators, anti-aging agents, and flexibility-imparting agents, and combinations thereof. Here, examples of the filler include, but are not limited to, cellulose powder, carbon black, silica, talc, titanium oxide, and combinations thereof. The crystal nucleating agent is not particularly limited as long as it can promote the crystallization of the polyolefin resin, and any inorganic or organic crystal nucleating agent can be used. The plasticizer, vulcanization accelerator and anti-aging agent are not particularly limited, and for example, commercially available products can be used.

  The content of other additive materials in the composition of the present invention is not particularly limited, and any amount can be selected by those skilled in the art in consideration of the content of the polyolefin, transpolyisoprene, and crosslinking agent.

  The polyolefin resin composition of the present invention is constituted by dynamically crosslinking a resin mixture containing a polyolefin resin, transpolyisoprene and a crosslinking agent, and other additive materials included as necessary. Here, the term “dynamic cross-linking” used in the present specification refers to cross-linking of transpolyisoprene formed during kneading processing of a resin mixture, and cross-linking of polyolefin resin and transpolyisoprene. Trans polyisoprene and the graft formed by cross-linking of polyolefin resin and trans polyisoprene are finely dispersed in the resin composition by shearing force by kneading. The ratio of dynamic crosslinking (crosslinking density) in such a resin composition can be easily changed by those skilled in the art, for example, by changing the conditions in the kneading step described later.

  The polyolefin resin composition of the present invention has a sea-island structure or a co-continuous structure in which transpolyisoprene is finely dispersed in a polyolefin resin matrix, and has improved impact resistance compared to the case of a polyolefin resin alone. As a result, the polyolefin resin composition of the present invention has a wider range of resin molded articles (for example, molded articles for automobiles) than the conventional polyolefin resin alone, which has been pointed out to have insufficient impact resistance and the like. , Molded products for home appliances, molded products for office use, and molded products for daily necessities).

  In place of the polyolefin resin, other thermoplastic resin is used, and the other thermoplastic resin, the transpolyisoprene, and the resin mixture containing the cross-linking agent are dynamically cross-linked. A thermoplastic resin composition with modified physical properties can also be obtained. In one embodiment, such other thermoplastic resins include, for example, polycarbonate resin, polyester resin, polyvinyl chloride resin, polystyrene resin, polyurethane resin, polyacrylonitrile resin, polyacryl resin, polyamide resin, polyacetal resin, A fluororesin, a polysulfone resin, a polyarylate resin, a polybutadiene resin, an acrylic rubber, and a combination thereof may be mentioned. Alternatively, in one embodiment, the other thermoplastic resin includes, for example, aromatic polycarbonate resin, polyethylene terephthalate resin, polybutylene terephthalate resin, polyvinyl chloride resin, polystyrene resin, polyurethane resin, acrylonitrile / styrene resin, acrylonitrile.・ Butadiene / styrene resin, styrene / butadiene block polymer, cellulose acetate resin, acrylic / chlorinated polyethylene resin, ethylene / vinyl alcohol resin, ethylene / vinyl acetate resin, fluorine resin, polyacrylic resin, polymethacrylic resin, methyl methacrylate resin , Methyl methacrylate / styrene resin, acrylic / chlorinated polyethylene resin, polyamide resin, polyacetal resin, polysulfone resin, polyethersulfur Resins, polyarylate resins, polyphenylene sulfide resins, polyphenylene oxide resins, polyether ether ketone resins, resins composed of alicyclic ethylenically unsaturated monomer units, ethylene / ethyl acrylate resins, and combinations thereof It is done.

(Manufacturing method of polyolefin resin composition)
In the production of the polyolefin resin composition of the present invention, first, the polyolefin resin, transpolyisoprene, a crosslinking agent, and, if necessary, the other additives are mixed to form a resin mixture.

  In obtaining the resin mixture, the polyolefin resin, transpolyisoprene, crosslinker and other additives can be mixed in various orders. In one embodiment, the polyolefin resin and transpolyisoprene are premixed and kneaded at a predetermined temperature, after which a cross-linking agent can be added to the kneaded product to form a resin mixture (in this case, the other additive materials are It can be added after kneading by a kneader described later). Alternatively, in another embodiment, the polyolefin resin, transpolyisoprene, cross-linking agent, and other additive materials are once charged directly into a kneading apparatus as described later, or once mixed in a separate container, whereby the resin mixture is obtained. Can be formed.

  Next, the resin mixture is kneaded under heating.

  Various kneading apparatuses can be used for this kneading. Examples of the kneading apparatus include, but are not limited to, a segment mixer, a Banbury mixer, a Brabender mixer, a pressure kneader, a single screw extruder, a twin screw extruder, an open roll, and the like.

  The temperature required for kneading can be set to any temperature by those skilled in the art in consideration of the melting point of the polyolefin resin to be used, the decomposition initiation temperature of transpolyisoprene, and / or the reaction temperature of the crosslinking agent. The temperature subjected to kneading is preferably 80 ° C to 240 ° C, more preferably 100 ° C to 200 ° C, and even more preferably 120 ° C to 180 ° C. If the temperature subjected to kneading is less than 80 ° C., dynamic crosslinking in the resin mixture becomes insufficient, and the impact resistance of the resulting resin composition may not be improved much compared to that of the polyolefin resin alone. is there. When the temperature for kneading exceeds 280 ° C., the molecular weight of the polyolefin resin and / or transpolyisoprene may decrease, and the mechanical properties of the resulting resin composition may decrease.

  The time required for kneading is not necessarily limited because it can vary depending on the total amount of the resin mixture to be used, the ratio of the content of the polyolefin resin, transpolyisoprene and cross-linking agent, and other additives constituting the resin mixture, It can be set at any time by those skilled in the art. The time required for kneading is preferably 3 minutes to 60 minutes, more preferably 5 minutes to 30 minutes. If the time required for kneading is less than 3 minutes, dispersion in the resin mixture and dynamic crosslinking become insufficient, and the impact resistance of the resulting resin composition may not be improved much compared to that of the polyolefin resin alone. There is. If the time required for kneading exceeds 60 minutes, thermal degradation and molecular chain scission of the polyolefin resin and / or transpolyisoprene in the resin mixture may occur, and the mechanical properties of the resulting resin composition may be reduced.

  Through the kneading, the resin mixture is dynamically crosslinked to obtain a resin composition having a sea-island structure or a co-continuous structure composed of a dispersed phase composed of transpolyisoprene and a matrix phase composed of a polyolefin resin. it can.

  In this way, the polyolefin resin composition of the present invention is produced.

  Although the transpolyisoprene component is crosslinked, the polyolefin resin composition of the present invention exhibits thermoplasticity as a whole resin composition due to the polyolefin resin as a constituent component. For this reason, the polyolefin resin composition of the present invention uses a known molding method for thermoplastic resins and the method such as an extrusion molding method, an injection molding method, a blow molding method, and a compression molding method. It can be molded into an arbitrary resin molded product by a molding apparatus. Furthermore, the obtained resin molded product can be further remolded.

  Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited to these examples.

Example 1
In a lab plast mill (kneader) equipped with a segment mixer whose temperature is adjusted to 150 ± 10 ° C., 20 g of homopolypropylene (F113G, manufactured by Prime Polymer Co., Ltd.) and transpolyisoprene derived from Eucommia ulmoides Oliver ( 20 g of Tochu Elastomer (registered trademark) manufactured by Hitachi Zosen Co., Ltd. was added and melt-kneaded under conditions of 50 rpm for 3 minutes. Next, 0.5 g of dicumyl peroxide (DCP) (manufactured by Kishida Chemical Co., Ltd.) is added as a crosslinking agent to the kneaded product obtained above, and further melt-kneaded for 16 minutes at 50 rpm. Thus, dynamic crosslinking was performed. Thereafter, 0.08 g of 4,6-bis (octylthiomethyl) -o-cresol (manufactured by BASF) was added as an anti-aging agent, and kneaded at a rate of 50 rpm for 1 minute. A sample was obtained. About this sample, the impact strength by the following Charpy impact test was measured, and the biomass degree was computed.

(Impact strength; Charpy impact test)
A sample of the polypropylene resin composition obtained above is cut into small pieces, and a Charpy impact test strip (80 × 10 ×) using a small injection molding machine (manufactured by Thermo Fisher Scientific Co., Ltd./model: HAAKE MiniJet Pro). 4 mm). The test piece was subjected to single notch processing using a notching machine (manufactured by INSTRON). For the Charpy impact test, an impact tester (manufactured by INSTRON) was used, and a test based on JIS K 7111-1 was performed. Table 1 shows the results of the obtained Charpy impact test.

(Biomass degree)
The biomass degree of the obtained sample was calculated from the following formula:

(Here, “mass of biomass-derived component” is the mass of transpolyisoprene used in this embodiment, and “total component weight” is the input polypropylene, transpolyisoprene, anti-aging agent, and organic peroxidation. The total mass of the object).

  The biomass degree of the sample of the polypropylene resin composition obtained in this example was 49.8%. The obtained results are shown in Table 1.

(Examples 2 and 3)
A sample of the polypropylene resin composition was prepared in the same manner as in Example 1 except that the amount of the crosslinking agent used in Example 1 was changed to the amount shown in Table 1, and the impact strength of the obtained sample and The biomass degree was evaluated in the same manner as in Example 1. The obtained results are shown in Table 1.

(Examples 4 to 6)
Table 1 shows 28 g of pellets of homopolypropylene (manufactured by Prime Polymer Co., Ltd., F113G) and 12 g of transpolyisoprene derived from Eucommia ulmoides Oliver (manufactured by Hitachi Zosen Co., Ltd., Eucommia elastomer (registered trademark)). A sample of the polypropylene resin composition was prepared in the same manner as in Example 1 except that the content of the crosslinking agent was changed to 0.5 parts by mass, 1.5 parts by mass, and 4.5 parts by mass, respectively. The impact strength and biomass degree of the obtained samples were evaluated in the same manner as in Example 1. The obtained results are shown in Table 1.

(Comparative Example 1)
Instead of the sample obtained in Example 1, impact strength and biomass degree were evaluated in the same manner as in Example 1 for 40 g of homopolypropylene (F113G, manufactured by Prime Polymer Co., Ltd.) pellets. The obtained results are shown in Table 1.

(Comparative Examples 2 and 3)
Without containing a cross-linking agent, homopolypropylene (Prime Polymer Co., Ltd., F113G) pellets and Eucommia ulmoides Olive-derived polypolyisoprene (manufactured by Hitachi Zosen Co., Ltd., Eucommia Elastomer (registered trademark)) are respectively shown. A sample of the polypropylene resin composition was prepared in the same manner as in Example 1 except that it was used in a content as described in 1. The impact strength and biomass degree of the obtained sample were the same as in Example 1. evaluated. The obtained results are shown in Table 1.

  As shown in Table 1, the polypropylene resin compositions obtained in Examples 1 to 3 have excellent impact strength, although there is no significant difference in the degree of biomass compared to the polypropylene composition obtained in Comparative Example 2. Had. It can be seen that the impact strength of the obtained polypropylene resin composition tended to increase as the content of the crosslinking agent increased.

(Observation of fracture surface of polypropylene resin composition sample)
For each observation sample obtained in Example 1 and Comparative Example 2, first, each strip produced for the Charpy impact test was immersed in n-hexane at 60 ° C. for 120 minutes, and each strip was The torn surface was solvent-etched to dissolve trans polyisoprene. Subsequently, gold samples were deposited by sputtering to obtain observation samples.

  Thereafter, the solvent-etched surface of each observation sample was observed with a scanning electron microscope (manufactured by Hitachi High-Technologies Corporation / model: Hitachi S3400-N). The obtained results are shown in FIG.

  According to FIG. 1, for example, on the solvent etching surface ((b) of FIG. 1) of the observation sample obtained from Example 1, there are a large number of pores in which transpolyisoprene has been dissolved by etching. , And the matrix of polypropylene present in the vicinity thereof. Thus, in the sample of the polypropylene resin composition obtained in Example 1, it can be seen that transpolyisoprene constitutes a continuous microstructure and that polypropylene forms a co-continuous structure.

  On the other hand, the etching surface (FIG. 1 (a)) obtained from the sample of Comparative Example 2 that was not subjected to dynamic crosslinking was observed on the etching surface of Example 1 (FIG. 1 (b)). It was not possible to find a pore having a size as expected.

(Example 7: Evaluation of interfacial adhesion)
Homopolypropylene (manufactured by Prime Polymer Co., Ltd., F113G) was put into a mold in a compression molding machine whose temperature was adjusted to 190 ° C., and a flat plate having a thickness of 1 mm was molded by pressurizing under a condition of 30 MPa for 5 minutes. Thereafter, the mold temperature was lowered to 30 ° C. or less by water cooling, and the flat plate was taken out. The flat plate obtained by this operation is referred to as “flat plate A”.

  On the other hand, transpolyisoprene derived from Eucommia ulmoides Oliver (manufactured by Hitachi Zosen Co., Ltd., Tochu Elastomer (registered trademark)) was put into a mold in a compression molding machine whose temperature was adjusted to 120 ° C., and the same as above. A flat plate was formed. The flat plate obtained by this operation is called “flat plate B”.

  Next, an acetone solution of 10 mg / mL dicumyl peroxide (DCP) was applied to a width of 1 cm above one surface of each of the flat plate A and the flat plate B. Then, after volatilizing acetone from the flat plate A and the flat plate B, the flat plate A and the flat plate B are superposed so that the DCP coated surfaces face each other, and this is put in a compression molding machine whose temperature is adjusted to 165 ° C. for 10 minutes. , Under a pressure of 0.5 MPa, the crosslinking reaction was allowed to proceed. Thereafter, the stacked flat plates were cut so that a 1 cm × 1 cm square DCP-coated surface remained in the center portion to obtain a 5 cm × 1 cm square test piece (also referred to as “test piece with DCP treatment”). .

  On the other hand, the test piece obtained by apply | coating only acetone to each surface of the flat plate A and the flat plate B, and pressurizing similarly to the above was produced (it is also called "the test piece without a DCP process").

  Next, a peel test was performed on each of the “test piece with DCP treatment” and the “test piece without DCP treatment” using a universal material testing machine (Autograph AGX-plus manufactured by Shimadzu Corporation). The test speed was 1 mm / min. FIG. 2 shows the results of the peel test.

  As shown in FIG. 2, the “test piece with DCP treatment” has a larger value for both the test force (vertical axis) and the stroke (horizontal axis) than the “test piece without DCP treatment”. It shows that the interfacial adhesive force between the flat plates is remarkably improved by performing cross-linking (dynamic cross-linking) by DCP between the flat plate A and the flat plate B, and the cross-linking between polypropylene and transpolyisoprene is improved. It can be seen that it was formed.

(Example 8)
Laboplast mill (kneader) equipped with a segment mixer whose temperature is adjusted to 150 ± 10 ° C., 36 g of high-density polyethylene (Bracem, SGE7252) pellets, and transpolyisoprene (Hitachi Shipbuilding Co., Ltd.) derived from Eucommia ulmoides Oliver 4 g of Tochu Elastomer (Registered Trademark) manufactured by Co., Ltd. was added and melt-kneaded under conditions of 50 rpm for 3 minutes. Next, 0.06 g of dicumyl peroxide (DCP) (manufactured by Kishida Chemical Co., Ltd.) is added as a cross-linking agent to the kneaded product obtained above, and further melt-kneaded for 6 minutes at 50 rpm. Thus, dynamic crosslinking was performed. Thereafter, 0.08 g of 4,6-bis (octylthiomethyl) -o-cresol (manufactured by BASF) was added as an anti-aging agent, and kneaded at 50 rpm for 1 minute. A sample was obtained. About this sample, the impact strength by the Charpy impact test was measured like Example 1, and the biomass degree was computed. The obtained results are shown in Table 2.

(Examples 9 and 10)
A sample of the polyethylene resin composition was prepared in the same manner as in Example 8 except that the amount of the crosslinking agent used in Example 8 was changed to the amount shown in Table 2, and the impact strength of the obtained sample and The biomass degree was evaluated in the same manner as in Example 1. The obtained results are shown in Table 2.

(Comparative Example 4)
Table 2 shows pellets of high-density polyethylene (manufactured by Braschem, SGE7252) and transpolyisoprene derived from Eucommia ulmoides Oliver (manufactured by Hitachi Zosen Co., Ltd., Eucommia Elastomer (registered trademark)) without containing a crosslinking agent. A sample of the polyethylene resin composition was prepared in the same manner as in Example 8 except that the content was as described, and the impact strength and the degree of biomass of the obtained sample were evaluated in the same manner as in Example 1. . The obtained results are shown in Table 2.

  As shown in Table 2, the polyethylene resin compositions obtained in Examples 8 to 10 have excellent impact strength, although there is no significant difference in the degree of biomass compared to the polyethylene composition obtained in Comparative Example 4. It turns out that it had.

  According to the present invention, a wider range of resin molded articles (for example, molded articles for automobiles, molded articles for home appliances) than conventional polyolefin resin alone, which has been pointed out that impact resistance is still insufficient. , Office molded articles, and daily molded articles).

Claims (10)

  A polyolefin resin composition obtained by dynamically crosslinking a resin mixture containing a polyolefin resin, transpolyisoprene and a crosslinking agent.   When the content of the trans polyisoprene is 100 parts by mass, the content of the polyolefin resin is from 80 parts by mass to 500 parts by mass, and the content of the crosslinking agent is from 0.1 parts by mass to 10 parts by mass. The polyolefin resin composition according to claim 1, wherein   The polyolefin resin composition according to claim 1 or 2, wherein the crosslinking agent is an organic peroxide.   The organic peroxide is dicumyl peroxide, 2,5-dimethyl-2,5-di (t-butylperoxy) hexane, and 2,5-dimethyl-2,5- (t-butylperoxy) -3. The polyolefin resin composition according to claim 3, which is at least one organic peroxide selected from the group consisting of hexyne.   The trans polyisoprene has a group of particles having an average particle diameter of 0.1 μm to 100 μm or a structure in which the particles are attached to each other, and the polyolefin resin composition forms a sea-island structure or a co-continuous structure; The polyolefin resin composition in any one of Claim 1 to 4.   A method for producing a polyolefin resin composition, the step of mixing a polyolefin resin, transpolyisoprene and a crosslinking agent to obtain a resin mixture; and the step of dynamically kneading the resin mixture by heating and kneading the resin mixture; Including the method.   The method according to claim 6, wherein the kneading step is performed at a temperature of 80 ° C. to 240 ° C.   When the content of the trans polyisoprene is 100 parts by mass, the content of the polyolefin resin is from 80 parts by mass to 500 parts by mass, and the content of the crosslinking agent is from 0.1 parts by mass to 10 parts by mass. 8. The method according to claim 6 or 7, wherein:   The method according to claim 6, wherein the cross-linking agent is an organic peroxide.   A resin molded product comprising the polyolefin resin composition according to any one of claims 1 to 5.