JP4926839B2 - Polyolefin resin composition - Google Patents

Description

  The present invention relates to a polyolefin resin composition having excellent antistatic properties, bleed resistance and slip resistance.

  Polyolefin resins are widely used as molding materials for films, molded products, fibers, etc., but there are problems such as static electricity is likely to be generated and accumulated, dust adheres to the surface, is easily contaminated, and lowers the product value. is there.

In order to solve such a problem, for example, Patent Document 1 discloses an antistatic agent composition mainly composed of diglycerin monofatty acid ester, which is used in combination with glycerin monofatty acid ester or alkyldiethanolamide. It is described that it is preferable. In polyolefin resin, when trying to obtain a good antistatic effect early after molding, the combined use of glycerin fatty acid ester is effective, but the blend of glycerin fatty acid ester also has drawbacks due to its strong cohesive strength. In long-term storage, the antistatic agent that bleeds on the surface is whitened (bloom phenomenon), causing poor appearance, and the bag made of polyolefin resin collapses due to increased slipperiness. It was.
JP-A-9-3273

  An object of the present invention is to provide a polyolefin resin composition having excellent bleed resistance and slip resistance while ensuring antistatic performance.

  The present invention provides a polyolefin resin composition containing a diglycerin fatty acid ester and an alkyldiethanolamide, wherein the glycerin fatty acid ester content in the composition is 100 ppm or less.

  The polyolefin resin composition of the present invention has a good antistatic effect, is excellent in bleed resistance, has no deterioration in surface condition, and is excellent in slip resistance and can suppress load collapse.

[Polyolefin resin]
The polyolefin resin used in the present invention refers to a polymer in which an olefin is a main constituent unit, each of which is an olefin homopolymer such as ethylene or propylene, or an ethylene-propylene block copolymer, a random copolymer, or Copolymers of ethylene and / or propylene with other olefins such as butene, pentene, hexene, and further copolymers of ethylene and / or propylene with other monomers such as vinyl acetate. It is done.

Among these, polypropylene resins such as propylene homopolymer, propylene-ethylene random copolymer, and propylene-ethylene block copolymer are preferable. The weight average molecular weight of the polypropylene resin is preferably 100,000 to 650,000. The weight average molecular weight is a value measured under the following conditions by gel permeation chromatography (GPC).
Apparatus: GPC 150C type column manufactured by Waters Co. Column: 3 AD80M / S manufactured by Showa Denko Corporation Measurement temperature: 140 ° C
Concentration: 20mg / 10ml
Solvent: Orthodichlorobenzene The melt flow rate (MFR) (JIS K6921, temperature 230 ° C., load 21.18 N) of the polypropylene resin is preferably 0.5 to 100 g / 10 min.

[Polyolefin resin composition]
The polyolefin resin composition of the present invention contains a polyolefin resin, a diglycerin fatty acid ester, and an alkyldiethanolamide, and the glycerin fatty acid ester content in the composition is 100 ppm or less.

  The diglycerin fatty acid ester used in the present invention is obtained by reacting diglycerin and a fatty acid, but the raw material diglycerin suppresses the formation of glycerin fatty acid ester to obtain excellent slip resistance, and further excellent charging. From the viewpoint of obtaining the prevention effect, the diglycerin content is preferably 90% by weight or more, more preferably 95% by weight or more. The number of carbon atoms of the fatty acid is preferably 8 to 22, more preferably 12 to 22, and still more preferably 12 to 18 from the viewpoint of obtaining excellent antistatic properties.

  The diglycerin content in the raw material diglycerin is a value measured by the following method.

  To a glass sample bottle, 2 mg of raw material diglycerin and 1.0 mL of a trimethylsilylating agent (“silylating agent TH”, manufactured by Kanto Chemical Co., Inc.) were added, sealed, and heated at 60 ° C. for 10 minutes. To this, 5.0 mL of ion-exchanged water and 1.0 mL of hexane were added and mixed, and then the hexane layer was quantified by the area ratio using a FID detector of gas chromatography (GLC) under the following conditions.

<GLC conditions>
Apparatus; Agilent Technologies 6890N type column; DB-1HT (manufactured by J & W Scientific) 30 m
Column temperature; initial = 100 ° C., final = 350 ° C.
Temperature rising rate = 10 ° C./min, held at 350 ° C. for 10 minutes Detector; FID, temperature = 330 ° C.
Injection part; split ratio = 50: 1, temperature = 330 ° C.
Sample injection volume: 1 μL
Carrier gas; helium, flow rate = 1.0 mL / min.

  From the viewpoint of obtaining an excellent antistatic effect, the reaction molar ratio of diglycerin and fatty acid is preferably 1.2 to 2.0 mol of fatty acid and more preferably 1.3 to 1.8 mol with respect to 1 mol of diglycerin. .

  The alkyldiethanolamide used in the present invention is represented by the following formula (I) and can be obtained by reacting a fatty acid or an ester thereof with diethanolamine.

(In the formula, R represents an aliphatic hydrocarbon group.)
The alkyldiethanolamide used in the present invention is preferably one having an acyl group having 8 to 22 carbon atoms, more preferably 12 to 22 carbon atoms, and particularly 12 to 18 carbon atoms. Specific examples include lauroyl diethanolamide and stearoyl diethanolamide.

  The weight ratio of diglycerin fatty acid ester to alkyldiethanolamide in the composition of the present invention is diglycerin fatty acid ester / alkyldiethanolamide = 30/70 to 75 / from the viewpoint of obtaining excellent antistatic properties and bleed resistance. 25 is preferable, and 50/50 to 70/30 is more preferable.

  From the viewpoint of obtaining an excellent antistatic effect, the content of the diglycerin fatty acid ester in the composition of the present invention is preferably 0.06 parts by weight or more, and 0.1 parts by weight or more with respect to 100 parts by weight of the polyolefin resin. Is more preferable. Moreover, from a viewpoint of preventing the appearance defect by blooming etc., 0.5 weight part or less is preferable and 0.3 weight part or less is more preferable. From this viewpoint, 0.06 to 0.5 part by weight is preferable, and 0.1 to 0.3 part by weight is more preferable.

  From the viewpoint of obtaining an excellent antistatic effect, the content of alkyldiethanolamide in the composition of the present invention is preferably 0.05 parts by weight or more, and 0.1 parts by weight or more with respect to 100 parts by weight of the polyolefin resin. More preferred. Moreover, from a viewpoint of preventing the appearance defect by blooming etc., 0.5 weight part or less is preferable and 0.3 weight part or less is more preferable. From this viewpoint, 0.05 to 0.5 part by weight is preferable, and 0.1 to 0.3 part by weight is more preferable.

  From the viewpoint of obtaining excellent slip resistance, the glycerin fatty acid ester content in the composition of the present invention is 100 ppm or less, preferably 80 ppm or less, and more preferably 60 ppm or less.

  In the present invention, the glycerin fatty acid ester content in the composition is the total content of glycerin monoester, diester and triester, and is a value measured by the following method.

  To a glass sample bottle, 15 mg of the composition of the present invention and 1.0 mL of a trimethylsilylating agent (“silylating agent TH”, manufactured by Kanto Chemical Co., Ltd.) were added, sealed, and heated at 60 ° C. for 10 minutes. To this, 5.0 mL of ion-exchanged water and 1.0 mL of hexane were added and mixed, and then the hexane layer was quantified by the area ratio using a FID detector of gas chromatography (GLC) under the following conditions.

<GLC conditions>
Apparatus; Agilent Technologies 6890N type column; DB-1HT (manufactured by J & W Scientific) 30 m
Column temperature; initial = 100 ° C., final = 380 ° C.
Temperature rising rate = 10 ° C./min, held at 380 ° C. for 27 minutes Detector; FID, temperature = 330 ° C.
Injection part; split ratio = 50: 1, temperature = 330 ° C.
Sample injection volume: 1 μL
Carrier gas; helium, flow rate = 1.0 mL / min.

  In addition to the above components, the composition of the present invention can contain other additional components as long as the effects of the present invention are not significantly impaired. Examples of other additional components include inorganic fillers such as talc, mica, calcium carbonate, glass fiber, silica, calcium silicate, magnesium sulfate, barium sulfate, and potassium titanate; condensed azo-based, isoindolinone-based, Organic pigments such as quinacridone, perylene, perinone, quinophthalone, anthraquinone, phthalocyanine; titanium white (titanium oxide), titanium yellow, zinc white, iron black, carbon black, petal, ultramarine, etc. Pigment-based, sulfur-based, phosphorous-based antioxidants; amine-based, triazole-based, benzophenone-based, benzoate-based, nickel-based, salicylic acid-based light stabilizers; organic nucleating agents such as dibenzylidene sorbitol; etc. Antistatic agent for lubricants; Lubricants such as higher alcohols and fatty acid amides; Flame retardants; Metal inertness Agent; molecular weight modifier; antibacterial agent; fluorescent whitening agents; anti-blocking agent and the like.

  When the resin composition of the present invention is formed into a molded body, it can be produced by blending diglycerin fatty acid ester and alkyldiethanolamide with polyolefin resin by a usual method, and further blending other additional components. May be. For example, powdered polyolefin resin is mixed with diglycerin fatty acid ester and alkyldiethanolamide, and other additional components as necessary. Pelletize. The pellets thus obtained are processed into a molded body by using a molding machine such as injection molding or sheet molding.

  The diglycerin fatty acid ester and alkyl diethanolamide of the present invention can obtain the same excellent antistatic effect even if a masterbatch is prepared in advance and then added to the polyolefin resin. The same effect can be obtained even if the master batch is a mixture of diglycerin fatty acid ester and alkyldiethanolamide, or a resin composition in which one of them is added to the other master batch. Can do.

  The polyolefin resin composition of the present invention can be used for any molded body that is molded by film molding, fiber molding, extrusion molding, hollow molding, injection molding, injection compression molding, foam molding or the like.

  In the following examples,% and part are% by weight and part by weight, respectively, unless otherwise specified.

Production Example 1
Using 1.0 mol of high-purity diglycerin with a diglycerin content of 96% and 1.5 mol of stearic acid, a dehydration and esterification reaction was carried out at 230 ° C. Thus, diglycerin stearic acid ester (referred to as ester-1) was obtained. The time required for the reaction was 6 hours. In addition, when the density | concentration of the glycerol fatty acid ester in a reaction product was analyzed using the gas chromatography, it was 3.5% (area ratio).

Production Example 2
Using 1.0 mol of high-purity diglycerin with 97% diglycerin content and 1.8 mol of lauric acid, dehydration and esterification reaction was carried out at 230 ° C. When the acid value reached 3, the reaction was terminated and cooled. Thus, diglycerin lauric acid ester (referred to as ester-2) was obtained. The time required for the reaction was 7.5 hours. In addition, when the density | concentration of the glycerol fatty acid ester in a reaction product was analyzed using the gas chromatography, it was 3.2% (area ratio).

Production Example 3
Using 1.0 mol of diglycerin with 45% diglycerin content and 1.5 mol of stearic acid, the dehydration and esterification reaction was carried out at 230 ° C. When the acid value reached 3, the reaction was terminated and cooled. A glycerin stearic acid ester (referred to as ester-3) was obtained. The time required for the reaction was 8 hours. When the concentration of glycerin fatty acid ester in the reaction product was analyzed using gas chromatography, it was 45.3% (area ratio).

Production Example 4
Using 1.0 mol of diglycerin content of 35% and 1.6 mol of behenic acid, a dehydration and esterification reaction was carried out at 230 ° C, and when the acid value reached 3, the reaction was terminated and cooled. A glycerin behenic acid ester (referred to as ester-4) was obtained. The time required for the reaction was 8 hours. When the concentration of glycerin fatty acid ester in the reaction product was analyzed using gas chromatography, it was 54.7% (area ratio).

Examples 1-3 and Comparative Examples 1-3
As the polyolefin resin, a resin of low density polyethylene (LD-PE) having a melt flow rate (MFR) of 1.9 (Ultzex 3021F, manufactured by Prime Polymer Co., Ltd.) was used. Using the super mixer which added the diglycerin fatty acid ester (ester-1-ester-4) obtained by 4 and the following alkyl diethanolamide and other components in the ratio shown in Table 1, and heated at 95 degreeC. By mixing, a polyolefin resin composition was obtained. The composition was pelletized using a twin-screw extruder set at 210 ° C., and then a 100 μm film was prepared using a T-die molding machine.

  About the obtained film, the antistatic property, the external appearance, and the slip resistance were evaluated by the following methods. The results are shown in Table 1.

<Alkyldiethanolamide>
Amide-1: Amizole SDHE (manufactured by Kawaken Fine Chemical Co., Ltd., carbon number 18,16 of acyl group)
Amide-2: Amizole SDE (manufactured by Kawaken Fine Chemicals Co., Ltd., carbon number of acyl group 18,16)
Amide-3: Aminone L-02 (manufactured by Kao Corporation, acyl group having 12 carbon atoms)
<Other ingredients>
GMS: Glycerol monostearate (Electro Stripper TS-5, manufactured by Kao Corporation)
<Antistatic evaluation method>
The film after molding was stored in a controlled room at 25 ° C. and 50% RH immediately after molding, and after 3 days, the surface resistivity was measured with a 4329A type high resistance meter (manufactured by Yokogawa Hewlett Packard).

<Observation of appearance>
Films stored in a room at 25 ° C. and 50% RH were visually observed after 14 days and evaluated according to the following criteria.
A: No bleed or whitening on the surface can be discerned by visual inspection.
Δ: The degree of whitening (bloom phenomenon) is small but observable.
X: The degree of whitening (bloom phenomenon) is large and can be observed easily.

<Slip resistance evaluation method>
A film stored in a room at 25 ° C. and 50% RH was measured for the static friction coefficient after 14 days according to the method of JIS K-7125.

Claims (4)

A polyolefin resin composition comprising 0.06 to 0.5 parts by weight of diglycerin fatty acid ester and 0.05 to 0.5 parts by weight of alkyldiethanolamide with respect to 100 parts by weight of polyolefin resin, A polyolefin resin composition having a glycerin fatty acid ester content of 100 ppm or less. The diglycerin fatty acid ester is an ester obtained by reacting 1.2 to 2.0 mol of a fatty acid having 8 to 22 carbon atoms with respect to 1 mol of diglycerin having a diglycerin content of 90% by weight or more. The polyolefin resin composition as described. 2. The alkyldiethanolamide has an acyl group having 8 to 22 carbon atoms.
Or the polyolefin resin composition of 2. The polyolefin resin composition according to any one of claims 1 to 3, wherein a weight ratio of diglycerin fatty acid ester to alkyldiethanolamide is diglycerin fatty acid ester / alkyldiethanolamide = 30/70 to 75/25.