JP4968848B2 - Polyolefin resin composition - Google Patents

Description

  The present invention relates to a polyolefin resin composition, and more particularly to a polyolefin resin composition excellent in transparency, heat resistance and mechanical strength.

  Polyolefin resins have the advantage of being excellent in molding processability, heat resistance, mechanical properties, low specific gravity and the like, and are widely used in films, sheets, and various molded products (structural parts, etc.). However, although the polyolefin resin itself generally has excellent physical properties, depending on certain uses, the original excellent performance of the resin cannot be brought out, so its application may be limited. there were.

  This drawback is derived from the crystallinity of the polyolefin-based resin. Various crystal nucleating agents are widely used to improve the transparency of the polyolefin-based resin and to impart heat resistance and mechanical strength. It has been broken. Such crystal nucleating agents include, for example, carboxylic acids such as sodium benzoate, aluminum 4-tert-butylbenzoate, sodium adipate and disodium bicyclo [2.2.1] heptane-2,3-dicarboxylate. Metal salts, sodium bis (4-tert-butylphenyl) phosphate, sodium-2,2′-methylenebis (4,6-ditert-butylphenyl) phosphate and lithium-2,2′-methylenebis (4,6-di) Examples thereof include compounds such as phosphoric acid ester metal salts such as tert-butylphenyl) phosphate, polyhydric alcohol derivatives such as dibenzylidene sorbitol, bis (methylbenzylidene) sorbitol and bis (dimethylbenzylidene) sorbitol.

  In addition, in order to improve the properties of polyolefin resins such as polyethylene, polypropylene, polybutene-1 and 1,2-polybutadiene, the addition of an amide compound is proposed, for example, in Patent Documents 1 to 9 below. As well known.

  Patent Document 1 proposes that a fatty acid diamide compound of phenylenediamine is blended in order to suppress deterioration of polypropylene in contact with a heavy metal such as copper, and an effect of suppressing deterioration due to heavy metal is shown. Patent Document 2 discloses that heat sealability and transparency are improved by blending a bisamide compound with a polyolefin polymer containing 5% by weight or more of polybutene-1. Furthermore, Patent Document 3 discloses that a crystalline polypropylene resin composition containing a large amount of β crystals can be obtained by adding an amide compound obtained from diamine and monocarboxylic acid to polypropylene. Furthermore, Patent Document 4 proposes a compound obtained by reacting naphthalenedicarboxylic acid or biphenyldicarboxylic acid with a monoamine.

Further, in Patent Documents 5 to 9, in each of the documents, a polycarboxylic acid-based resin is referred to as a polypropylene-based resin, a polyethylene-based resin, a polyester-based resin, a polyamide-based resin, and a crystalline synthetic resin collectively referred to as engineering plastic. A method containing an amide compound, a polyamine amide compound or a polyamino acid amide compound has been proposed.
JP 50-105558 A JP 51-114482 A JP-A-6-107875 JP-A-5-310665 JP-A-6-220269 JP-A-6-234890 JP-A-6-263969 JP-A-6-271762 JP-A-8-157640

  However, the fatty acid diamide compound of phenylenediamine described in Patent Document 1 is not practical for polypropylene resins because its effect as a crystal nucleating agent is small. Further, bisamide compounds described in Patent Document 2 (N, N′-dioctadecyl-nonanediamide shown as Sample Nos. 3-5 and 3-6 described in Table 3 on page 7 of the specification) ) Alone, no effect of improving the transparency to polypropylene was observed, and polybutene-1 had to be blended. Furthermore, the amide compound obtained from diamine and monocarboxylic acid described in Patent Document 3 is a β crystal nucleating agent, but in a polypropylene resin composition, β crystal has a lower melting point than α crystal. Since the heat resistance is low and the transparency of the molded product is poor, it was not suitable for providing a polypropylene resin composition having both heat resistance and transparency. Furthermore, the compound obtained by reacting naphthalenedicarboxylic acid or biphenyldicarboxylic acid and monoamine described in Patent Document 4 was not satisfactory because of a small effect of improving transparency.

  Furthermore, none of the polycarboxylic acid-based amide compounds, polyamine-based amide compounds, or polyamino acid-based amide compounds described in Patent Documents 5 to 9 can satisfy the transparency improvement effect for polyolefin resins.

  In addition, when adding an amide compound to a polyolefin-based resin, it is known that when ethylene bisstearylamide used as a lubricant is used in combination, the processability is improved, but the transparency and heat resistance of the processed molded product And the improvement effect of mechanical strength was not recognized or very small.

  Furthermore, today, the performance required for polyolefin resins, particularly polypropylene resins, has become higher, and there has been a demand for crystal nucleating agents that can further improve transparency and impart other properties. The current situation is that the proposals are not enough.

  Then, the objective of this invention is providing the polyolefin resin composition excellent in transparency, heat resistance, and mechanical strength.

  As a result of intensive studies to solve the above problems, the present inventors have found that the object can be achieved by adding a specific amount of 2,5-piperazinedione compound to a polyolefin resin composition. The headline and the present invention were completed.

（式（１）中、Ｒ^１及びＲ^２は、フェニルメチル基である。）
で表される２，５−ピペラジンジオン化合物０．０１〜１０質量部を配合してなることを特徴とするものである。 That is, the polyolefin resin composition of the present invention is represented by the following general formula (1) with respect to 100 parts by mass of the polyolefin resin.

(In formula (1), R ¹ and R ² are phenylmethyl groups.)
It mix | blends 0.01-10 mass parts of 2, 5- piperazine dione compounds represented by these, It is characterized by the above-mentioned.

  According to the present invention, it is possible to provide a polyolefin resin composition having excellent transparency, heat resistance and mechanical strength by blending the 2,5-piperazinedione compound as a crystal nucleating agent with a polyolefin resin. it can.

The polyolefin resin composition of the present invention is described in detail below.
Examples of the polyolefin resin used in the polyolefin resin composition of the present invention include low density polyethylene, linear low density polyethylene, high density polyethylene, isotactic polypropylene, syndiotactic polypropylene, hemiisotactic polypropylene, cyclohexane. Α-olefin polymers such as olefin polymer, stereoblock polypropylene, poly-3-methyl-1-butene, poly-3-methyl-1-pentene, poly-4-methyl-1-pentene, ethylene / propylene block or random Examples include α-olefin copolymers such as copolymers.

  Among the above-mentioned polyolefin resins, polypropylene resins having a remarkable effect of using the crystal nucleating agent according to the present invention are suitable. Polypropylene, ethylene / propylene block or random copolymer, α-olefin other than ethylene / A propylene block or random copolymer, a mixture of these propylene-based polymers and other α-olefin polymers, and the like are particularly preferably used.

  In the polyolefin resin composition of this invention, the 2, 5- piperazine dione compound represented by the said General formula (1) or General formula (2) is mix | blended with the polyolefin resin mentioned above as a crystal nucleating agent.

1 to 18 carbon atoms which may have a substituent or a branch represented by R ¹ , R ² , R ³ and R ⁴ in the general formulas (1) and (2) As the alkyl group, for example, methyl group, ethyl group, propyl group, isopropyl group, butyl group, secondary butyl group, tertiary butyl group, isobutyl group, pentyl group, isopentyl group, tertiary pentyl group, hexyl group, 2-hexyl group, 3-hexyl group, heptyl group, 2-heptyl group, 3-heptyl group, isoheptyl group, tertiary heptyl group, n-octyl group, isooctyl group, tertiary octyl group, 2-ethylhexyl group, nonyl Group, isononyl group, decyl group, dodecyl group, tridecyl group, tetradecyl group, pentadecyl group, hexadecyl group, peptadecyl group or octadecyl group.

  These alkyl groups may be interrupted by an oxygen atom, a sulfur atom, a carbonyl group, an ester group, an amide group, an imino group or the following aryl group, and the hydrogen atom in the alkyl group is a hydroxy group, a halogen atom, an amino group. Groups, nitro groups, cyano groups, alkenyl groups, alkenyloxy groups, alkanoyloxy groups, chained aliphatic groups such as alkoxycarbonyl groups, pyrrole, furan, thiophene, imidazole, oxazole, thiazole, pyrazole, isoxazole, isothiazole, Pyridine, pyridazine, pyrimidine, pyrazine, piperidine, piperazine, morpholine, 2H-pyran, 4H-pyran, phenyl, biphenyl, triphenyl, naphthalene, anthracene, pyrrolidine, pyridine, indolizine, indole, isoindole, indah Lumpur, purine, quinolizine, quinoline, isoquinoline, or cyclic aliphatic groups may be substituted, such as cycloalkyl groups below. These interruptions or substitutions may be combined.

  The alkyl group includes a hydroxyalkyl group, an alkoxyalkyl group, an alkylaminoalkyl group, a dialkylaminoalkyl group, an alkoxycarbonylalkyl group, a carboxyalkyl group, a halogenated alkyl group, an alkanoyloxyalkyl group, an aminoalkyl group, and the like. Can do.

  Examples of the hydroxyalkyl group include a hydroxymethyl group, a 2-hydroxyethyl group, a 3-hydroxypropyl group, a 4-hydroxybutyl group, a 2-hydroxybutyl group, a 1-hydroxypentyl group, and a 6-hydroxyhexyl group. As in the case of the alkyl group, the alkyl group in the hydroxyalkyl group may be interrupted, the hydrogen atom in the hydroxyalkyl group may be substituted, or the interruption and substitution may be combined.

  Examples of the alkoxyalkyl group include a methoxymethyl group, a methoxyethyl group, a methoxybutyl group, an ethoxyhexyl group, an ethoxymethyl group, a butoxyethyl group, a t-butoxyhexyl group, and a hexyloxymethyl group. Similar to the group, the alkyl group in the alkoxyalkyl group may be interrupted, the hydrogen atom in the alkoxyalkyl group may be substituted, and the interruption and substitution may be combined.

  Examples of the alkylaminoalkyl group include a methylaminomethyl group, an ethylaminomethyl group, a hexylaminomethyl group, an ethylaminoethyl group, a hexylaminoethyl group, a methylaminopropyl group, a butylaminopropyl group, a methylaminobutyl group, Examples include ethylaminobutyl group, hexylaminobutyl group, methylaminohexyl group, ethylaminohexyl group, butylaminohexyl group, hexylaminohexyl group, and the like. The hydrogen atom in the alkylaminoalkyl group may be substituted, and the interruption and substitution may be combined.

  Examples of the dialkylaminoalkyl group include a dimethylaminomethyl group, a diethylaminomethyl group, a dihexylaminomethyl group, a diethylaminoethyl group, a dihexylaminoethyl group, a dimethylaminopropyl group, a dibutylaminopropyl group, a dimethylaminobutyl group, and a diethylaminobutyl group. Group, dihexylaminobutyl group, dimethylaminohexyl group, diethylaminohexyl group, dibutylaminohexyl group, dihexylaminohexyl group and the like, and similarly to the alkyl group, even if the alkyl group in the dialkylaminoalkyl group is interrupted Often, hydrogen atoms in a dialkylaminoalkyl group may be substituted, and interruptions and substitutions may be combined.

  Examples of the alkoxycarbonylalkyl group include a methoxycarbonylmethyl group, a methoxycarbonylethyl group, a methoxycarbonylhexyl group, an ethoxycarbonylmethyl group, an ethoxycarbonylethyl group, a propoxycarbonylmethyl group, an isopropoxycarbonylmethyl group, and a butoxycarbonylmethyl group. , Pentyloxycarbonylmethyl group, hexyloxycarbonylmethyl group, hexyloxycarbonylbutyl group, hexyloxycarbonylhexyl group and the like. Like the alkyl group, the alkyl group in the alkoxycarbonylalkyl group may be interrupted. , A hydrogen atom in an alkoxycarbonylalkyl group may be substituted, and interruption and substitution may be combined.

  Examples of the carboxyalkyl group include a carboxymethyl group, a carboxyethyl group, a carboxybutyl group, a carboxyhexyl group, and the like, the alkyl group in the carboxyalkyl group may be interrupted, Hydrogen atoms in the carboxyalkyl group may be substituted, and interruptions and substitutions may be combined.

  Examples of the halogenated alkyl group include a monochloromethyl group, a monobromomethyl group, a monoiodomethyl group, a monofluoromethyl group, a dichloromethyl group, a dibromomethyl group, a diiodomethyl group, a ditrifluoromethyl group, a trichloromethyl group, and a trichloromethyl group. Examples include bromomethyl group, triiodomethyl group, trifluoromethyl group, dibromobutyl group, diiodobutyl group, difluorobutyl group, chlorohexyl group, bromohexyl group, iodohexyl group, and fluorohexyl group. In addition, the alkyl group in the halogenated alkyl group may be interrupted, the hydrogen atom in the halogenated alkyl group may be substituted, or the interruption and substitution may be combined.

  Examples of the alkanoyloxyalkyl group include an acetoxymethyl group, 2-acetoxyethyl group, propionyloxymethyl group, 1-hexanoyloxy-2-methylpentyl group, and the like. The alkyl group in the alkyl group may be interrupted, the hydrogen atom in the alkanoyloxyalkyl group may be substituted, and the interruption and substitution may be combined.

  Examples of the aminoalkyl group include an aminomethyl group, an aminoethyl group, an aminopropyl group, an aminobutyl group, an aminopentyl group, an aminohexyl group, and the like. The group may be interrupted, a hydrogen atom in the aminoalkyl group may be substituted, and the interruption and substitution may be combined.

As an aryl group which may have a substituent having 6 to 18 carbon atoms and represented by R ¹ , R ² , R ³ and R ⁴ in the general formulas (1) and (2), a phenyl group 4-hydroxyphenyl group, 3,4,5-trimethoxyphenyl group, 4-tert-butylphenyl group, biphenyl group, naphthyl group, methylnaphthyl group, anthracenyl group, phenanthryl group, etc. The hydrogen atom may be substituted with a hydroxy group, a halogen atom, a nitro group, a cyano group, an alkyl group, an alkoxy group, an alkenyl group, an alkenyloxy group, an alkoxyalkyl group, an alkanoyloxy group, or an alkoxycarbonyl group.

The optionally substituted cycloalkyl group having 3 to 12 carbon atoms represented by R ¹ , R ² , R ³ and R ⁴ in the general formulas (1) and (2) is a cyclopropyl group. , A cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, a cyclononyl group, a cyclodecyl group, etc., and a hydrogen atom in the cycloalkyl group is a halogen atom, an alkyl group, an alkoxy group, an alkenyl group, an alkenyloxy group, It may be substituted with an alkoxyalkyl group, an alkanoyloxy group, an alkoxycarbonyl group, a nitrile group or a cyano group.

Carbon substituted with an aryl group which may have a substituent of 6 to 18 carbon atoms represented by R ¹ , R ² , R ³ and R ⁴ in the general formulas (1) and (2) Examples of the alkyl group which may have a substituent having 1 to 18 atoms include phenylmethyl group (benzyl group), 3-phenylpropyl group, 4-phenylbutyl group, 5-phenylpentyl group, and 6-phenylhexyl group. A compound having a structure of the alkyl group substituted with a 2- (4-hydroxyphenyl) ethyl group or the aryl group, and R ¹ and R ² in the general formulas (1) and (2) are phenyl A methyl group is preferred. The hydrogen atom in the alkyl group substituted with an aryl group is a hydroxy group, a halogen atom, a nitro group, a cyano group, an alkyl group, an alkoxy group, an alkenyl group, an alkenyloxy group, an alkoxyalkyl group, an alkanoyloxy group, or an alkoxycarbonyl group. The alkyl group in the alkyl group substituted with an aryl group may be interrupted with an oxygen atom, a sulfur atom, a carbonyl group, an ester group, an amide group, or an imino group. Also, the above substitutions and interruptions may be combined.

Substituted by a cycloalkyl group represented by R ¹ , R ² , R ³ and R ⁴ in the general formulas (1) and (2), which may have a substituent having 3 to 12 carbon atoms. Examples of the alkyl group which may have a substituent having 1 to 18 carbon atoms include 1-cyclohexylmethyl group, 2-cyclohexylethyl group, 3-cyclohexylpropyl group, 2-cyclohexyloxyethyl group, and 2-cyclohexyloxyphenyl. Examples of the hydrogen atom in the cyclohexyl group include a hydroxy group, a halogen atom, a nitro group, a cyano group, an alkyl group, an alkoxy group, an alkenyl group, an alkenyloxy group, an alkoxyalkyl group, an alkanoyloxy group, and an alkoxy group. The alkyl group in the alkyl group which may be substituted with a carbonyl group and substituted with a cyclohexyl group is oxygen Child, a sulfur atom, a carbonyl group, an ester group, an amide group, may be interrupted by an imino group. Also, the above substitutions and interruptions may be combined.

  As the specific structure of the compound represented by the general formula (1) in the present invention, the following compound No. 1-No. 15 is mentioned. However, the present invention is not limited by the following compounds.

  In the polyolefin resin composition of the present invention, the 2,5-piperazinedione compound is 0.01 to 10 parts by mass, preferably 0.02 to 1 part by mass, more preferably 100 parts by mass of the polyolefin resin. Is blended in an amount of 0.05 to 0.5 parts by mass. If the amount is less than 0.01 parts by mass, the effect of addition is insufficient. If the amount is more than 10 parts by mass, the surface of a molded product obtained by molding the polyolefin resin composition may be bleed.

  In addition, the polyolefin resin composition of the present invention may include a conventionally known plasticizer, antioxidant, heat stabilizer, light stabilizer, ultraviolet absorber, pigment, colorant, various fillers, antistatic agent, if necessary. , Mold release agents, fragrances, lubricants, flame retardants, foaming agents, fillers, antibacterial agents, antifungal agents, various additives such as crystal nucleating agents other than the compounds represented by formula (1) or (2) May be blended.

  In the polyolefin resin composition of the present invention, the method of blending the compound represented by the general formula (1) or (2) with the polyolefin resin is not particularly limited, and is performed by a conventionally known method. be able to. For example, the polyolefin resin powder or pellets and the additive may be mixed by dry blending, or a part of the additive may be preblended and then dry blended with the remaining components. After dry blending, for example, mixing may be performed using a mill roll, a Banbury mixer, a super mixer, or the like, and kneading may be performed using a single screw or twin screw extruder. This mixing and kneading is usually performed at a temperature of about 120 to 220 ° C. A method of adding an additive in the polymerization stage of a synthetic resin, a mixture of a binder, a wax, a solvent, a granulation aid such as silica and the like in advance at a desired ratio, and then granulation to obtain a one-pack composite additive. A method of adding the pack composite additive to the polyolefin resin, a method of preparing a master batch containing the additive at a high concentration, and adding the master batch to the polyolefin resin can be used.

  When molding the polyolefin resin composition of the present invention, it is possible to carry out molding such as extrusion molding, injection molding, blow molding, vacuum molding, compression molding, etc., as in the case of general plastics. Sheets, bars, bottles, containers Various molded products such as these can be easily obtained.

  EXAMPLES Hereinafter, although a synthesis example and an Example are given and this invention is demonstrated further more concretely, this invention is not restrict | limited at all by the following Examples. In addition, a synthesis example is a manufacturing method of the 2, 5- piperazine dione compound represented by General formula (1) based on the synthetic resin composition of this invention, and an Example shows the polyolefin resin composition of this invention. .

Synthesis example 1
Compound No. 8 was synthesized according to the reaction formula (1).

Reaction formula (1)

  Under a nitrogen atmosphere, 5.0 g of phenylalanine and 40 ml of ethylene glycol were mixed, heated to 180 ° C. and reacted for 4 hours. After completion of the reaction, the reaction mixture was cooled to room temperature, and the precipitated solid was filtered off. The filtrate was washed with water and ethanol and dried to obtain 1.84 g (yield 41%) of white crystals. When the obtained white crystals were analyzed, the target compound No. 8 was identified. The results of these analyzes are shown below.

IR [KBr tablet method] (cm ⁻¹ )
1338, 1458, 1674, 2923, 3060, 3205

GC / MS: (m / z)
294, 203, 175, 91 (target compound: 294)

Example 1 and Comparative Example 1
An ethylene / propylene random copolymer having an melt flow index of 10 g / 10 min at 230 ° C. and 21.2 N (ethylene content; 3 mass%, number average molecular weight; 9.5 × 10 ⁴ , weight average molecular weight; 5 .8 × 10 ⁵ ) 100 parts by mass of phenol-based antioxidant; 0.1 parts by mass of tetrakis [methylene-3- (3 ′, 5′-ditert-butyl-4′-hydroxyphenyl) propionate] methane Phosphorus antioxidant: 0.1 part by mass of tris (2,4-ditert-butylphenyl) phosphite, 0.05 part by mass of calcium stearate, and 0.1 part by mass of the compound shown in Table 1 below , Mixed with Henschel mixer (FM200; manufactured by Mitsui Mining Co., Ltd.) at 1000 rpm for 1 minute, and then mixed at 240 ° C. with a single screw extruder (OEX3024; manufactured by DIM Co., Ltd.). Extruded to to produce pellets in processing conditions a screw speed of rpm. About the obtained pellet, after drying at 90 degreeC for 3 hours, the following evaluation was implemented.

(Crystallization temperature)
The obtained pellet was heated to 230 ° C. at a rate of 50 ° C./min with a differential scanning calorimeter (Diamond; manufactured by Perkin Elmer), held for 10 minutes, and then at a rate of −10 ° C./min. In the chart obtained by cooling to the end, the peak top of the endotherm was taken as the crystallization temperature. These results are shown in Table 1 below.

(Degree)
The obtained pellets were filled into a mold for 40 seconds at an injection temperature of 230 ° C. and an injection pressure of 70-80 MPa using an injection molding machine (EC100-2A; manufactured by Toshiba Machine Co., Ltd.). After cooling in the mold for 20 seconds, injection molding was performed under the condition of taking out the sheet from the mold to obtain a sheet having a square of 60 mm square and a thickness of 1 mm. Immediately after the injection molding, the sheet was allowed to stand for 48 hours or more in a thermostatic bath having a bath temperature of 23 ° C., and then a haze guard II (manufactured by Toyo Seiki Seisakusho Co., Ltd.) was used to measure the test piece (Haze). Asked. In addition, it shows that the transparency of a test piece is so favorable that this figure is low. These results are shown in Table 1 below.

(Transparency)
The obtained pellets were filled into a mold for 40 seconds at an injection temperature of 230 ° C. and an injection pressure of 70-80 MPa using an injection molding machine (EC100-2A; manufactured by Toshiba Machine Co., Ltd.). After cooling in the mold for 20 seconds, injection molding was performed under the condition of taking out the sheet from the mold to obtain a sheet having a square with a side of 60 mm and a thickness of 2 mm. Immediately after injection molding, the sheet was allowed to stand for 48 hours or more in a thermostatic bath having a temperature of 23 ° C., and the transparency was determined with Haze Guard Plus (manufactured by Toyo Seiki Seisakusho). In addition, it shows that the transparency of a test piece is so favorable that this figure is high. These results are shown in Table 1 below.

(Flexural modulus)
The obtained pellets were filled into a mold for 40 seconds at an injection temperature of 230 ° C. and an injection pressure of 70-80 MPa using an injection molding machine (EC100-2A; manufactured by Toshiba Machine Co., Ltd.). After cooling in the mold for 20 seconds, injection molding was performed under the condition of taking out the sheet from the mold, and a bending test piece having a length of 80 mm, a width of 10 mm, and a thickness of 4 mm was produced. The bending test piece was allowed to stand for 48 hours or longer immediately after injection molding in a thermostatic bath having a bath temperature of 23 ° C., and then subjected to a bending elastic modulus (AG-IS, manufactured by Shimadzu Corporation). MPa). These results are shown in Table 1 below.

＊１）結晶核剤未配合

* 1) Without crystal nucleating agent

  From Table 1, the polyolefin resin composition not using the 2,5-piperazinedione compound according to the present invention as a crystal nucleating agent could not satisfy the physical properties such as transparency, flexural modulus and elongation. On the other hand, it was confirmed that the polyolefin resin composition of the present invention using a specific 2,5-piperazinedione compound was excellent in transparency and physical properties from Example 1. Moreover, the polyolefin resin composition of Example 1 also had a high crystallization temperature, and showed favorable heat resistance.

Claims (1)

The following general formula (1) with respect to 100 parts by mass of the polyolefin resin:

(In formula (1), R ¹ and R ² are phenylmethyl groups. )
A polyolefin resin composition comprising 0.01 to 10 parts by mass of a 2,5-piperazinedione compound represented by the formula: