JPH069834A - Polypropylene-based resin composition - Google Patents

Abstract

PURPOSE:To provide the subject polypropylene-based resin composition useful as a raw material of a molding exhibiting respectively excellent impact resistance, mechanical strength, transparency, printability, low-temperature heat- sealing properties, radiation resistance, etc., without reducing characteristics essential to PP. CONSTITUTION:This polypropylene-based resin composition contains characteristically 30 to 99wt.% polypropylene-based resin and 1 to 70wt.% ethylene-based copolymer containing 2 to 50wt.% acrylamide derivative-derived unit.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polypropylene resin composition which is useful as a raw material for a molded article excellent in impact resistance, mechanical strength, transparency, printability, low temperature heat sealability, radiation resistance and the like. .

[0002]

2. Description of the Related Art Polypropylene resins are generally inexpensive and their characteristics are transparency, mechanical strength, heat resistance, surface gloss, chemical resistance, oil resistance, rigidity, bending fatigue resistance, etc. It is used in a wide range of fields such as industrial materials, food packaging materials, cosmetic packaging materials, and chemical packaging materials by taking advantage of the properties of. However, among polypropylene-based resins (hereinafter sometimes abbreviated as PP), homopolypropylene resins are hard and have a high glass transition temperature, so that they are very brittle at low temperatures, easily broken, and have poor transparency. There was a problem. Propylene / ethylene random copolymer resins and block polypropylene resins are well known as solutions to these problems to some extent. However, the transparency and gloss of the propylene / ethylene random copolymer were still insufficient. Block polypropylene resins, on the other hand, generally have ethylene / propylene rubber or polyethylene resin dispersed in PP,
Manufactured by a method that balances impact resistance and rigidity. However, the transparency was markedly hindered due to the difference in refractive index between the two mixed.

Further, since PP is generally a hydrophobic resin, it is inferior in printability and dyeability, and a method of subjecting a molded article of PP to surface treatment such as corona treatment, flame treatment and sulfuric acid treatment is known. ing. However, there has been a problem that the surface tension decreases with time after the surface treatment. Also,
Since PP has a tertiary carbon in the molecular skeleton, there is a problem that the physical properties are significantly deteriorated when irradiated with radiation. As a method for solving these problems, as a method for improving transparency, a dibenzylidene sorbitol derivative described in Polymer Digest, July 1984, p. 116 and Polymer Digest, June, 1985, p. 43 is blended with PP. However, a method of expressing transparency by the nucleating agent effect is well known. As a method of blending the dibenzylidene sorbitol derivative with PP, further, JP-A-58-185632 and JP-A-53-11704 are known.
4, JP-A-58-101136 and JP-A-5-
8-84728, JP-A-58-87024, JP-A-58-129036, JP-A-58-1.
34714, JP-A-58-157840,
JP-A-58-157841, JP-A-58-158
Many methods have been proposed, such as Japanese Laid-Open Patent Publication No. 223 and Japanese Laid-Open Patent Publication No. 54-77654. However, these methods have problems such that they decompose during molding, an offensive odor is generated, and the impact resistance is lowered due to the nucleating agent effect.

On the other hand, a method of blending a hydrogenated terpene resin and a nucleating agent with PP and quenching them with cooling water to obtain a transparent sheet (JP-A-1-171833, JP-A-1-1718).
No. 34), a method of blending PP and an ethylene / α-olefin copolymer and quenching at 60 ° C. or lower (JP-A 1-2).
No. 99851) is known. However, these methods require a special molding device, and it has been difficult to easily obtain a transparent product with a general-purpose molding device. As a method of improving impact resistance, a method of containing 5 to 20% of polyisobutene (Japanese Patent Publication No. 35-1064).
No. 0), ethylene / propylene copolymer 5-20
% Blending method (JP-B-35-7088),
A method of blending high-molecular-weight low-pressure polyethylene (JP-B-37-6975, JP-B-37-15067), a method of blending polyethylene with ethylene and ethylene / propylene rubber, so-called propylene / ethylene block copolymer (Kuroda; Polymer, Volume 28, No. 1
0, 714, 1979) and the like are known. However, these methods have a problem that they are inferior in gloss and transparency.

As a method of improving printability, in addition to the above-mentioned surface treatment method, a method of applying a mineral oil or a higher fatty acid to a polyolefin film (JP-A-4-65438, JP-A-4-65439, etc.) Is proposed. However, this method still has problems such as poor wetting during coating, blooming of the coating material, and curling of the film. PP is excellent in bending (hinge property) among polyolefin resins, but when folded, the folds are whitened, and when a constant tension is applied, the part to which the tension is applied is whitened and locally whitened. You can see the phenomenon. Generally, this whitening is observed to run at right angles to the direction of stress, and this phenomenon is called stress whitening (Str
ess Whit-ing), and the occurrence of local molecular orientation called Creze is said to be the cause of whitening. For these mechanisms, see OKSPURR, WPNIEGISCH,
J. Appl. Polymer Sci. Vol. 6, page 585 (196
2), CB BUCHNALL, RRSMITH, POLYMER, LOND., Vo
l. pp. 6,437 (1965), RP KAMBOUR, Appl. P
Olymer Symposia, Vol. 7, page 215 (1965) and the like. For research on stress whitening, see Motoyoshi,
Lubricity and lubricants of plastics (Nikkan Kogyo Shimbun, 197)
7). As a whitening prevention method,
Conventionally, a method of kneading a lubricant or a plasticizer has been adopted.
However, this method causes blades and blooms,
There were problems such as deterioration of transparency.

On the other hand, in the medical packaging field, P
For the molded article of P, the sterilization means by irradiating the gamma ray with cobalt 60 or the electron beam is adopted. However, due to the molecular structure of PP, the molecular chains are easily broken by irradiation with radiation, and deterioration progresses, resulting in deterioration of physical properties such as impact resistance and tensile elongation. As a method of preventing the deterioration of polypropylene due to such irradiation with radiation, when an antioxidant is added to PP to improve the radiation resistance, a phenolic antioxidant particularly produces a phenoxy radical upon irradiation with radiation, There is a problem that the molded product turns yellow.
The following proposals have been made as solutions to these problems.

An ethylene / propylene random copolymer resin having an ethylene content of 2.8 to 7.0% by weight (JP-A-60-
55005), polypropylene or an ethylene content of 2 to be obtained by blending an ethylene / propylene random copolymer having an ethylene content of 2% by weight or less and an ethylene / propylene random copolymer having an ethylene content of 4% by weight or more. Method of blending diallyl (iso) phthalate or triallyl (iso) cyanurate to 4% by weight of ethylene / propylene random copolymer blend (JP-A-60-168740), melt flow rate in the presence of radical generator From 0.05 to 10 g / 10 minutes to 1
Propylene homopolymer block adjusted to 0 to 100 g / 10 minutes 5 to 95% by weight and ethylene content 2 to 15
100 parts by weight of a propylene block copolymer consisting of 5 to 95% by weight of a propylene / ethylene random copolymer block and 0.05 to 0.5 of a sorbitol compound
PP composition consisting of 1 part by weight (Japanese Patent Application Laid-Open No. 60-215047)
Gazette), 5 to 95 parts by weight of a propylene homopolymer block and 2 to 15% by weight of ethylene in propylene /
A resin composition comprising 100 parts by weight of a propylene block copolymer consisting of 95 to 5 parts by weight of an ethylene random copolymer block and 0.05 to 0.5 parts by weight of a sorbitol compound (JP-A-60-215048). , Polypropylene or propylene / ethylene random copolymer 100
A resin composition in which 0.005 to 0.2 parts by weight of an organic peroxide and 0.01 to 0.5 parts by weight of triallyl (iso) cyanurate or diallyl (iso) phthalate are mixed in parts by weight (JP-A-61-73711). Gazette), propylene homopolymer or propylene / ethylene random copolymer having an ethylene content of 3.0% by weight or less, ethylene / propylene random copolymer having an ethylene content of 4.0 to 15.0% by weight. And a mixture of organic peroxides, wherein the ethylene content in the total amount of these homopolymers and copolymers is 1.5 to 4.5% by weight, and the total of the homopolymers and copolymers Quantity 10
The mixing ratio of the organic peroxide to 0 parts by weight is 0.001-
0.25 parts by weight, melt flow index 15 g /
There has been no proposal for a composition (Japanese Patent Application Laid-Open No. 61-159437) for 10 minutes or more. None of these methods has sufficient transparency, or the effect of suppressing deterioration of physical properties such as impact resistance and tensile elongation after irradiation with radiation is not sufficient.

Further, as a method for improving the low temperature heat-sealing property of PP, a method of blending PP with ethylene / propylene elastomer or ethylene / propylene / butene-1 copolymer which is a copolymer of ethylene and α-olefin is used. And a method of blending polybutene-1
No. 28351, JP-A-54-60348, etc.) are known. However, these methods still have insufficient low temperature heat sealability.

[0009]

Therefore, according to the present invention, impact resistance, mechanical strength, transparency, printability, low temperature heat sealability, radiation resistance, etc. can be achieved without impairing the inherent properties of PP. It is an object of the present invention to provide a polypropylene resin composition which is useful as a raw material for a molded article excellent in heat resistance.

[0010]

Means for Solving the Problems As a result of various studies to solve the above problems, the present inventors have found that by blending a specific ethylene copolymer resin with a polypropylene resin, It was found that the purpose could be achieved. The present invention has been completed based on such findings. That is, the present invention relates to (A) polypropylene resin 30 to 9
Provided is a polypropylene resin composition comprising 9% by weight and (B) 1 to 70% by weight of an ethylene copolymer resin containing an ethylene unit and an acrylamide derivative and / or a methacrylamide derivative unit. .

Next, each component contained in the resin composition of the present invention will be described. In the resin composition of the present invention,
The polypropylene resin as the component (A) is homopolypropylene, ethylene / propylene random polypropylene (including ethylene-propylene rubber; the same applies hereinafter), ethylene-propylene block polypropylene (including ethylene-propylene rubber. .),
Mixture of homo polypropylene and ethylene / propylene random polypropylene, mixture of homo polypropylene and ethylene / propylene block polypropylene, mixture of ethylene / propylene random polypropylene and ethylene / propylene block polypropylene), homo polypropylene and polyethylene and / or ethylene and carbon Mixture of α-olefin copolymer resin having a number of 4 to 12, ethylene / propylene random polypropylene and polyethylene, and / or ethylene and α- having a carbon number of 4 to 12
Mixture with olefin copolymer resin, ethylene / propylene block polypropylene and polyethylene and / or mixture of ethylene and α-olefin copolymer resin having 4 to 12 carbon atoms, homopolypropylene and ethylene / propylene random polypropylene and polyethylene and / Or a mixture of ethylene and an α-olefin copolymer resin having 4 to 12 carbon atoms, homopolypropylene, ethylene / propylene block polypropylene and polyethylene, and / or ethylene and α-olefin copolymer resin having 4 to 12 carbon atoms. A mixture, ethylene / propylene random polypropylene, ethylene / propylene block polypropylene and polyethylene, and / or a mixture of ethylene and an α-olefin copolymer resin having 4 to 12 carbon atoms, and the like. Among these, when ethylene / propylene random polypropylene or ethylene / propylene block polypropylene is used, the compatibility with the ethylene copolymer resin as the component (B) tends to be better than when homopolypropylene is used. However, on the other hand, when homopolypropylene is used, the transparency is further improved probably because it functions as a crystallization nucleating agent. As a copolymer of ethylene and an α-olefin having 4 to 12 carbon atoms,
For example, ethylene / butene-1 copolymer, ethylene / 4
-Methylpentene-1 copolymer, ethylene / hexene-
1 copolymer or such a polyolefin resin grafted with an unsaturated carboxylic acid or an anhydride thereof in the presence of an organic peroxide or copolymerized with another monomer (eg, methyl acrylate, ethyl acrylate, etc.) Things are included.

The resin composition of the present invention further contains, as the component (B), an ethylene-based copolymer resin containing ethylene units and acrylamide derivative and / or methacrylamide derivative units. For such copolymer resins, Journal of Polymers, Vol. 35, No. 12, p. 795 (197)
8), U.S. Pat. No. 3,629,209, JP-B-43
-21655, Japanese Patent Publication No. 44-19537,
JP-B-43-23766, JP-B-43-9063
It can be obtained by an ordinary method described in JP-A No. 63-304010.

The acrylamide derivative and / or methacrylamide derivative constituting the component (B) are N-alkyl derivatives and N, N-dialkyl derivatives. Specifically, N-methylacrylamide, N-ethylacrylamide, Nn-propylacrylamide, N-isopropylacrylamide, Nn-butylacrylamide, N-isobutylacrylamide, Nt-butylacrylamide, N, N- Dimethyl acrylamide, N,
N-diethyl acrylamide, N-ethyl methacrylamide, N-n-propyl methacrylamide, Nt-butyl methacrylamide, N, N-dimethyl methacrylamide, N, N-diethyl methacrylamide, etc. are mentioned, and these are independent. Can be used in or as a mixture. Of these, N-ethylacrylamide, N-
Isopropyl acrylamide, Nt-butyl acrylamide, N, N-dimethyl acrylamide, N, N-diethyl acrylamide, Nn-propyl acrylamide, Nt-butyl acrylamide and the like are preferable.

The content of the acrylamide derivative and / or the methacrylamide derivative unit in the ethylene copolymer resin is usually 2 to 50% by weight, and 5 to 45% by weight.
Is preferred. When the content is less than 2% by weight, when it is mixed with PP, its modifying effect is poor, which is not preferable. On the other hand, when it exceeds 50% by weight, the flexibility of the copolymer is gradually lost, and when blended with PP, the resin composition obtained is inferior in mechanical properties, which is not preferable. In addition,
The ethylene-based copolymer resin used in the present invention can contain units derived from other polymerizable monomers, together with ethylene and an acrylamide derivative and / or a methacrylamide derivative. Here, as other polymerizable monomers, ester compounds each having an unsaturated bond,
Examples thereof include acid compounds, ether compounds and hydrocarbon compounds.

Examples of the ester compound having an unsaturated bond include vinyl acetate, methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate,
Hexyl acrylate, octyl acrylate, lauryl acrylate, benzyl acrylate, N, N-dimethylaminoethyl acrylate, methyl methacrylate, ethyl methacrylate, propyl methacrylate, butyl methacrylate, hexyl methacrylate, octyl methacrylate, Lauryl methacrylate, N, N-dimethylaminoethyl methacrylate, methyl fumarate, ethyl fumarate, propyl fumarate, butyl fumarate, dimethyl fumarate, diethyl fumarate, dipropyl fumarate, dibutyl fumarate, methyl maleate, Examples thereof include ethyl maleate, propyl maleate, butyl maleate, dimethyl maleate, diethyl maleate, dipropyl maleate and dibutyl maleate.

Examples of the acid compound having an unsaturated bond include acrylic acid, methacrylic acid, maleic acid and fumaric acid. Examples of the ether compound having an unsaturated bond include methyl vinyl ether,
Examples include ethyl vinyl ether, propyl vinyl ether, butyl vinyl ether, octadecyl vinyl ether, and phenyl vinyl ether. Furthermore, examples of the hydrocarbon compound having an unsaturated bond include styrene, norbornene, butadiene, acrylonitrile, methacrylonitrile, acrolein, crotonaldehyde, trimethoxyvinylsilane, vinyl chloride, and the like.
Examples thereof include vinylidene chloride.

It is preferable that the above-mentioned polymerizable monomer basically does not react with the acrylamide derivative and the methacrylamide derivative, but if the amount used is selected in consideration of stoichiometry, it reacts with these derivatives. It is also possible to use possible monomers. Further, one kind or two or more kinds of the above polymerizable monomers can be used depending on the intended use. The content of these polymerizable monomers is 40% by weight or less. If this content exceeds 40% by weight, the original characteristics of the ethylene copolymer resin will be impaired. In order for the ethylene-based copolymer resin to exhibit the original properties as polyethylene, the total amount of acrylamide derivative, methacrylamide derivative and other polymerizable monomer is preferably 50% by weight or less in the resin. , 45 wt% or less is even more preferable.

In particular, for applications requiring transparency, it is preferable to contain at least 3% by weight of other polymerizable monomers, and more preferably at least 5% by weight, in order to reduce the crystallinity of polyethylene. Preferably
It is most preferable to contain at least 10% by weight. Further, when used in a field where oil resistance is required in applications such as industrial materials, it is preferable to select a highly polar polymerizable monomer and copolymerize it. Here, examples of the highly polar polymerizable monomer include acrylonitrile, acrylic acid, and acrylic acid ester. Further, in the field of food packaging, low odor and low taste as well as hygiene are strongly required. Therefore, in the field,
The polymerizable monomer depends on the odor and the amount remaining in the copolymer and cannot be unconditionally limited, but it is preferably 10% by weight or less, and more preferably 3% by weight or less. Especially for laminates for which strict odorlessness and tastelessness are required, is there any use of polymerizable monomers with strong odor?
Alternatively, it is very small, preferably 1% by weight or less.

The mixing ratio of the components in the resin composition of the present invention is (A) polypropylene resin 30 to 99.
It is necessary to make the range of 1 to 70% by weight and the ethylene copolymer resin (B) 1 to 70% by weight. If the proportion of polypropylene resin is less than 30% by weight, the properties originally possessed by the resin may be impaired, and if it exceeds 99% by weight, transparency, impact resistance, radiation resistance, printability, etc. The improvement effect of does not appear and it cannot be used. On the other hand, when the proportion of the ethylene-based copolymer resin is less than 1% by weight, the effect of improving transparency, impact resistance, radiation resistance, printability, etc. does not appear,
If it exceeds 70% by weight, the properties originally possessed by the polypropylene resin are impaired and the polypropylene resin cannot be used. Polypropylene resin 40 to 98% by weight and ethylene copolymer resin 2 to
It is preferably in the range of 60% by weight.

The blending method for obtaining the resin composition of the present invention is not particularly limited, and for example, it is preferable to pelletize using a ribbon blender, a high speed mixer, a kneader, a pelletizer, a mixing roll and the like and dry. On the other hand, each component of the resin composition of the present invention may be directly supplied to a molding machine and molded. The melting index (MFR, measured according to JIS-K6758 at a load of 2.16 kg and a temperature of 230 ° C.) of the resin composition of the present invention is not particularly limited and is appropriately selected depending on the molding method and extruded. In the case of molding, the range of 0.1 to 100 is preferable.

The resin composition of the present invention may further contain other additives commonly used for thermoplastic resins. Examples of such additives include 2,5-di-t-butylhydroquinone as an antioxidant; 2,6-
Di-t-butyl-p-cresol; 4,4'-thiobis- (6-t-butylphenol); 2,2-methylene-
Bis (4-methyl-6-t-butylphenol); octadecyl 3- (3 ', 5'-di-t-butyl-1'-hydroxyphenyl) propionate; 4,4'-thiobis- (6-butylphenol), etc. , Ethyl-2-cyano-3,3-diphenylacrylate as a UV absorber, 2- (2'-hydroxy-5-methylphenyl) benzotriazole, 2-hydroxy-4-octoxybenzophenone, phthalic acid as a plasticizer Fatty esters of polyhydric alcohols (polyhydric alcohol monostearate, sorbitan monopalmitate) such as dimethyl, glycerin, dipropylene glycol, triethylene glycol, diethylene glycol, diethyl phthalate, wax, liquid paraffin, and phosphate ester as antistatic agents. Etc.), sulfated oleic acid, Li oxide, such as carbowax, as a lubricant ethylenebis stearamide and butyl stearate, carbon black as a colorant, phthalocyanine, quinacridone, indoline,
Examples of fillers include azo pigments, titanium oxide, red iron oxide, and the like, such as glass fiber, asbestos, mica, ballastonite, calcium silicate, aluminum silicate, and calcium carbonate. Also, many other polymer compounds can be blended within a range that does not impair the action and effect of the present invention.

The resin composition of the present invention can be formed into films, sheets, tubes, bottles and the like by the known melt molding method and compression molding method, and can also be made into a laminate by various lamination methods. As a stacking method, for example,
A so-called dry lamination molding method or sand lamination method in which a single layer product of the resin composition of the present invention is laminated with a dry lamination adhesive such as a urethane-based or acrylic-based adhesive, or a co-extrusion lamination or co-extrusion method. There are various methods such as a method (feed block, multi-manifold method), a co-injection molding method, a co-extrusion pipe molding method, a solution coat molding method in which the resin composition of the present invention is dissolved in a solvent and coated.

Other thermoplastic resins that can be used for lamination include polyethylene resins, polypropylene resins, polyolefin resins such as copolymer resins of ethylene and α-olefins having 3 to 12 carbon atoms, polystyrene resins, polyethylene terephthalate resins, Examples thereof include polyvinyl chloride resin, polycarbonate resin, polyamide resin, saponified ethylene / vinyl acetate copolymer resin, polyvinylidene chloride resin, polyvinyl alcohol resin and the like. Examples of the above-mentioned copolymer resin of ethylene and α-olefin having 3 to 12 carbon atoms include ethylene / butene-1 copolymer, ethylene / 4-methylpentene-1 copolymer, ethylene / hexene-1 copolymer. Polymer, modified polypropylene blended with ethylene / propylene rubber, modified polybutene, modified poly-4-methylpentene-1, grafting unsaturated carboxylic acid or its anhydride on such polyolefin resin in the presence of organic peroxide Examples thereof include those obtained by copolymerization or copolymerization with other monomers (for example, methyl acrylate, ethyl acrylate, etc.).

The multilayer laminate obtained by the various methods as described above is further reheated by using a vacuum molding machine, a compression molding machine, a stretch blow molding machine or the like to apply a stretching operation, or the above-mentioned multilayer. The laminate can be subjected to a heat stretching operation using a uniaxial or biaxial stretching machine. The layer structure of the multilayer laminate is A / B / C, C / B / when the layer made of the resin composition of the present invention is A layer, the adhesive resin layer is B layer, and the other thermoplastic resin layer is C layer. Typical examples include A / B / C and C / B / metal foil / A / B / C. Incidentally, the thermoplastic resin of both outer layers, even if different resins,
The same resin may be used. Further, for the adhesive resin layer, so-called dry lamination adhesive such as urethane-based, acrylic-based, polyester-based and the known adhesive resin in the coextrusion molding method can be used. For example,
There is a resin obtained by grafting or copolymerizing an unsaturated carboxylic acid, an acid anhydride or an ester monomer with a polyolefin resin.
As the grafting method, a method in which a polyolefin resin is melted and graft-modified with the above components in the presence of an organic peroxide,
Alternatively, there is a method in which a polyolefin resin is dissolved in hot xylene and the above components are grafted in the presence of an organic peroxide. Here, examples of the unsaturated carboxylic acid, acid anhydride, and ester monomer include acrylic acid, methacrylic acid, ethacrylic acid, glycidyl methacrylate, and acrylic acid 2-.
Hydroxyethyl, 2-hydroxyethyl methacrylate, diethyl maleate, monoethyl maleate, di-n-butyl maleate, maleic acid, maleic anhydride, fumaric acid, fumaric anhydride, itaconic acid, itaconic anhydride, Examples include 5-norbornene-2,3-anhydride, citraconic acid, citraconic anhydride, crotonic acid, crotonic anhydride, acrylonitrile, methacrylonitrile, sodium acrylate, calcium acrylate, magnesium acrylate and the like. These graft polymers are described in US Pat.
953655, JP-A-51-98784, JP-B-44-15423, and JP-B-49-48.
22 and the like.

[0025]

The reason why the above-mentioned problems can be solved by the present invention has not been clarified yet, but since the ethylene copolymer resin is rich in flexibility, wettability and impact resistance, It is conceivable that when they are mixed, they have some effect on each other to compensate for the defects while maintaining the original properties of both.

[0026]

EXAMPLES Next, the present invention will be described more specifically based on examples, but the present invention is not limited thereto. Reference Example (Preparation of Ethylene Copolymer Resin) Polymerization was carried out in an autoclave type reactor divided into 2 zones with an internal volume of 4 liters at a temperature of 190 to 210 ° C. and a pressure of 11
It was carried out using t-butylperoxypivalate as an initiator under the conditions of 00 to 1300 atm. Using N, N-dimethylacrylamide and acrylamide as the acrylamide component, other monomers and / or solvents were injected upstream of the second stage compressor and fed with ethylene to the first zone of the reactor. The purified copolymer was separated from unreacted monomers by a high pressure separator and a low pressure separator, and pelletized by using an extruder. The following copolymers (a) to (e) were produced by the above method. The acrylamide derivative content of each copolymer was measured using an infrared spectrometer and ¹³ C-NMR, and the MFR was 190 ° C. according to JIS-K6760.
The load was measured at 2.16 kg.

(A) Ethylene / N, N-dimethylacrylamide copolymer MFR3.5 (g / 10 minutes), N, N-dimethylacrylamide content = 19.2 wt% (b) Ethylene / N, N- Dimethylacrylamide copolymer MFR 3.7 (g / 10 minutes), N, N-dimethylacrylamide content = 37 wt% (c) Ethylene / acrylamide copolymer MFR 4.6 (g / 10 minutes), acrylamide content = 1
1.4 wt% (d) Ethylene / methyl methacrylate / N, N-dimethylacrylamide copolymer MFR5.1 (g / 10 min), methylmethacrylate content = 6.2 wt%, N, N-dimethylacrylamide containing Amount = 9.1% by weight (e) Ethylene / N, N-dimethylacrylamide / maleic anhydride copolymer MFR 7.4 (g / 10 min), ethylene content 87.9% by weight, N, N-dimethylacrylamide Content 8.2% by weight, maleic anhydride content = 3.9% by weight

Examples 1 to 15 and Comparative Examples 1 to 3 The polypropylene type resins and ethylene type copolymers shown in Table 1 were used in an extruder with KTX-37 type same-direction twin-screw vent manufactured by Kobe Steel. The resin composition was manufactured by melt mixing at 230 ° C. A test for measuring the Izod impact strength and flexural modulus of the obtained resin composition using a Sumitomo Heavy Industries, Ltd. mini mat 7/8 ounce injection molding machine under the conditions of an injection temperature of 230 ° C. and a mold temperature of 45 ° C. Created a piece. Next, these test pieces were left to stand in a thermostatic chamber at a temperature of 23 ° C. and a relative humidity of 50% for 7 days for conditioning, and the temperature was 23 ° C. and a relative humidity of 50%.
The Izod impact strength with notch was measured according to ASTM-D256, and the flexural modulus was measured according to ASTM-D790. The results are shown in Table 1.

The symbols relating to PP shown in Table 1 have the following meanings. A: The MFR at 230 ° C and a load of 2.16 kg is 8.1 (g /
10 minutes) homopolymer B: ethylene content 3.2% by weight, 230 ° C., load 2.16
Propylene / ethylene random copolymer with an MFR in kg of 8.4 (g / 10 min) C: Dibenzylidene sorbitol 0.3 as a clarifying nucleating agent
5% by weight added, ethylene content 7.1% by weight, 230
MFR at ℃, load 2.16kg is 20.1 (g / 10min)
Propylene / ethylene random copolymer

[0030]

[Table 1]

Example 16 and Comparative Examples 4 to 6 Example 2, Example 5, Example 8, Example 9, Example 1
2. With respect to the resin compositions of Example 14 and Comparative Examples 1 to 3, using a 10 ounce injection molding machine manufactured by Nissei Plastic Industry Co., Ltd., a thickness of 2 was obtained under the conditions of an injection temperature of 230 ° C. and a mold temperature of 45 ° C.
A flat plate having a size of 10 mm and 10 × 12 cm was formed. About this molded product, Shishido Co., Ltd. electrostatic electrostatic nest meter, S-51
The charging half-life time was measured using a 09-type (100V, 80VA, 1550RPM). Also, Yokogawa HEWLE
The volume resistivity was measured using an electric resistance measuring device 16008 manufactured by TT-PACKARD Co., Ltd. Next, using the same flat plate, spray Nippon Paint Flexen 101, and
A cross-cut test (paintability test) of IS-K5400 was performed. The results are shown in Table 2. Further, in order to observe stress whitening, the flat plate was bent and the whitening phenomenon was observed. As a result, no whitening phenomenon was observed on any of the flat plates of the examples, but the flat plate of the comparative example easily whitened.

[0032]

[Table 2]

Examples 22 to 27 and Comparative Examples 7 to 9 In the compounding ratio of the resin compositions used in Examples 16 to 21 and Comparative Examples 4 to 6, tetrakis [methylene (3,5- Di-t-butyl-hydroxyphenyl)
Propionate] methane 0.05% by weight, calcium stearate 0.05% by weight and dibenzylidene sorbitol
0.35% by weight was added and mixed well. 40m after mixing
It was extruded and pelletized at 230 ° C. with a mφ single screw extruder. Using these pellets, a flat plate having a thickness of 2 mm and 10 × 12 cm was molded under the same molding conditions using the above injection molding machine. This plate was irradiated with 3 Mrad of γ-ray with a cobalt 60 radiation source to evaluate the radiation resistance of the plate. The tensile test was performed according to JIS-K6758. The impact resistance strength was evaluated by the falling weight impact strength, which is an energy value (kg-cm) required to break the weight by dropping the weight from a certain height using the above flat plate. The results are shown in Table 3. In Table 3, the symbols of the measurement items mean the following. I: Tensile strength (kg / cm ² ) II: Tensile elongation (%) III: Drop weight impact strength (kg-cm)

[0034]

[Table 3]

[0035]

[Table 4]

Examples 28 to 33 and Comparative Examples 8 to 9 Example 2, Example 5, Example 8, Example 9, Example 1
2. Using the resin compositions of Example 2, Comparative Example 2 and Comparative Example 3, a 40 mmφ cast film molding machine was used to obtain a film having a thickness of 40 μm. Next, this film is 5m
Using a heat sealing machine having a m × 200 mm heat sealing bar, heat sealing pressure 1 k at each set temperature
Heat sealing was performed under the conditions of g / cm ² and heat sealing time of 1.0 seconds, a test piece with a width of 15 mm was taken out, and 10 test pieces were measured with a tensile tester at a pulling speed of 500 mm / min. The T-type peel strength was calculated by rounding off. Moreover, Haze was measured according to ASTM-D1003 using a Toyo Seiki Seisakusho Haze meter. The results are shown in Table 4.

Comparative Examples 10 to 13 PPs of Comparative Examples 2 and 3 were mixed with an ethylene / propylene / butene-1 copolymer (M at a temperature of 230 ° C. and a load of 2.16 kg).
FR = 5.3 g / 10 min, ethylene content 2.3% by weight, propylene content 84.2% by weight, butene-1 content 13.5% by weight) or ethylene / propylene elastomer (temperature 23
After thoroughly mixing 10 wt% of each of MFR at a temperature of 0 ° C and a load of 2.16 kg with 3.7 g / 10 min and an ethylene content of 70% by weight, a temperature of 230 ° C and 40 mmφ were measured.
A resin composition was obtained using a single screw extruder. Using these resin compositions, heat seal peel strength and HAZE were measured in the same manner as in Example 28, and the results are shown in Table 4. The symbols in Table 4 represent the following. EPB: ethylene / propylene / butene-1 copolymer EPR: ethylene / propylene elastomer

[0038]

[Table 5]

[0039]

[Table 6]

[0040]

EFFECTS OF THE INVENTION The polypropylene resin composition of the present invention has excellent characteristics such as flexibility, impact strength, mechanical strength, transparency, low temperature heat sealability, antistatic property, printability and radiation resistance. Produce a product. Therefore, the resin composition of the present invention is expected to be effectively used as various industrial materials, industrial packaging materials, food packaging materials, medical device materials, pharmaceutical packaging materials, cosmetic packaging materials and vinyl chloride substitutes.

Claims (4)

[Claims] 1. (A) Polypropylene resin 30 to 99
A polypropylene resin composition comprising 1% to 70% by weight of an ethylene copolymer resin containing 1% by weight and (B) an ethylene unit and an acrylamide derivative and / or a methacrylamide derivative unit. 2. The polypropylene resin composition according to claim 1, wherein the content of the acrylamide derivative and / or methacrylamide derivative unit of the ethylene copolymer resin is 2 to 50% by weight. 3. The polypropylene resin composition according to claim 1, wherein the acrylamide derivative is N-alkyl-substituted acrylamide or N, N-dialkyl-substituted acrylamide. 4. The polypropylene resin composition according to claim 1, wherein the acrylamide derivative is N, N-dimethylacrylamide.