JPS61281142A - Resin composition for extrusion molding - Google Patents

Abstract

PURPOSE:To provide a resin composition obtained by compounding a specific ethylene copolymer with zeolite and an organic amide compound, and having excellent transparency, well-balanced slipperiness and printability and practically acceptable blocking property. CONSTITUTION:The objective composition is produced by compounding (A) 100pts.(wt.) of an ethylene copolymer produced by the use of a Ziegler catalyst and having a density of 0.910-0.940g/cm<3>, a melt flow rate of 0.01-20g/10min and a comonomer content of 1-10wt% with (B) 0.01-1pt. of zeolite having an average particle diameter of <=20mu and (C) 0.01-1pt. of an organic amide compound obtained by mixing a saturated fatty acid amide to an unsaturated fatty acid amide at a ratio of about 3:1.

Description

Detailed Description of the Invention [Industrial Application Field] The present invention is directed to the extrusion of a linear ethylene copolymer that has blocking properties suitable for practical use and has a good balance of transparency, slip properties, and printability. The present invention relates to a molding resin composition.

[Conventional technology]

Polypropylene has been known as a material for extruded products such as films with good transparency. This polypropylene film is widely used as various packaging materials because of its excellent rigidity.

However, polypropylene film is not suitable for general-purpose processing methods such as air-cooled inflation molding, and has the disadvantages of poor impact strength (especially low-temperature impact strength) and low-temperature heat sealability, so its application fields are limited. has been limited. Therefore, in the general-purpose film field, high-pressure low-density polyethylene and low-pressure high-density polyethylene, which are resins that compensate for these drawbacks, have come to be widely used.

[Problem that the invention seeks to solve]

However, although these resins are effective in compensating for the above drawbacks, they have the drawback of poor transparency.

On the other hand, linear ethylene copolymers are resins with excellent mechanical strength such as impact strength, low-temperature impact strength, and environmental stress fracture (ESCR), as well as heat sealability and hot tack properties, which are much better than the general-purpose resins mentioned above. It is. In addition to the well-known T-die molding method and water-cooled inflation molding method, methods for molding a highly transparent film of this copolymer include an air-cooled inflation molding method with a near ring for rapid cooling (for example, Japanese Patent Application Laid-Open No. 146764-1983). General-purpose processing methods such as

However, if a linear ethylene copolymer is simply molded into a film using these molding methods, although the film transparency is good, it is completely impractical in terms of the anti-blocking and slip properties of the film. It becomes a thing. However, this results in disadvantages such as unsatisfactory transparency and inability to maintain a balance between physical properties.

The purpose of the present invention is to eliminate these drawbacks, and to improve the balance of the above-mentioned qualities while maintaining the good properties of linear ethylene copolymers.

[Means for solving problems]

That is, the present invention includes each of the following components (a) to (c), and the component (b) is 0.0 parts by weight per 100 parts by weight of the Al component.
This is a resin composition for extrusion molding, characterized in that the blending ratio of the c1 component is 1 to 1 part by weight and 0.01 to 1 part by weight.

(a) Density 0 produced using Ziegler catalyst
．． 910=0.940 g/crn”, Melt 7!:
l-1/-) 0.01 to 20 g/10 min and a comonomer content of 1 to 10% by weight ethylene copolymer (bl Zeolite (c) with an average particle size of 20 μ or less
Organic amide compound The composition of the present invention is excellent in the above points and is therefore particularly suitable for extrusion molded products, such as films and laminate materials.

[For production]

The above component (a) used in the present invention is produced using a Ziegler catalyst and has a density of 0.910 to 0.940 g/
Ethylene copolymers having a melt flow rate of 0.01 to 20 g/10 min and a comonomer content of 1 to 10% by weight are suitable.

Preferably, the density is 0.915 to 0.930 g/am'
, a melt flow rate of 0.1 to 15 g/10 minutes and a comonomer content of 2 to 8% by weight.

If the density is below the above range, the blocking of the film or the like when made into a composition will be greatly reduced and the effect of the present invention will be low, and if the density is above the range, there will be disadvantages such as poor transparency and impact strength. Exists.

Also, those with a melt flow rate below the above range have poor processability, and those with a melt flow rate above the above range have the disadvantage of reduced processability and impact strength of the film, etc.

Furthermore, comonomer contents outside the above range have disadvantages such as undesirable clarity, impact strength, and rigidity of the final target composition.

More preferably, those having a flow ratio of 6 to 15 are desirable in terms of extrusion processability and transparency.

Such a copolymer is produced by combining ethylene with one or more copolymers such as propylene, butene-1, hexene-1,4-methylpentene-11-octene-1, etc., using a pressure cuff, Qkg/cm. It is obtained by polymerizing at a low temperature, and the method described in Japanese Patent Publication No. 56-18132 is known as a manufacturing method.

The above-mentioned component (top) used in the present invention has an average particle size of 20 μm or less,
Preferably it is a zeolite with a diameter of 5μ or less.

Anything larger than 20μ will impair the appearance of the film.

The zeolite may be natural or synthetic. For example, C3100 (product name manufactured by Nihon Kagaku Kogyo Co., Ltd.)
and U47 (trade name manufactured by Mizusawa Chemical Co., Ltd.).

Furthermore, the above (c1 component) used in the present invention is an organic amide compound. Preferred specific examples include unsaturated fatty acid amide,
Contains saturated fatty acid amides.

The mixing ratio of these components (al to (c)) is such that the (bl component is 0.01 to 1 part by weight, preferably 0.1 to 0.6 part by weight, per 100 parts by weight of the (al component), and (c
) component is 0.01 to 1 part by weight, preferably 0.05 to 0
．． It is 3 parts by weight.

(If the amount of the BL component is less than the above range, the blocking property when formed into a film will deteriorate, which is undesirable; if it exceeds the above range, the transparency when formed into a film will decrease significantly.

If component (c) is below the above range, the slip properties and blocking properties will be significantly reduced, and if it is above the range, not only will there be too much slip, but the printability and heat sealability will also be significantly deteriorated, which is undesirable.

In order to achieve a particularly satisfactory balance of transparency, blocking properties, and slip properties, preferably, in the process of producing these compositions, granules with a size of 200 μm or less are used as component (a), and first ( Use a composition produced in the following order: Component a) and BL component are thoroughly mixed with a blender such as a Henschel mixer, and component (c) is further added to this mixture and the mixed mixture is pelletized with an extruder. It is desirable to do so.

In order to achieve a particularly satisfactory balance of blocking properties, slip properties, transparency, and printability, a mixture of unsaturated fatty acid amide and saturated fatty acid amide in a ratio of about 3:1 as component (c) is used in the above-mentioned production process. Particularly desirable are compositions that are pelletized by a process. Preferred unsaturated fatty acid amides include erucic acid amide and oleic acid amide, and preferred saturated fatty acid amides include behenic acid amide and stearic acid amide.

In the present invention, commonly used antioxidants, stabilizers,
Stabilizers such as antifogging agents, antistatic agents, UV agents, and nucleating agents may be added.

(Al components include not only the above-mentioned copolymers, but also blends of the above-mentioned copolymers with other resins such as high-pressure low-density polyethylene, high-density polyethylene, polypropylene, polybutene, and ethylene-vinyl acetate copolymers). It is also possible to apply talc in combination with the zeolite component (b) in a total amount of 1 part by weight or less per 100 parts by weight of component (a), which is preferable because blocking is good and no foaming phenomenon occurs due to moisture absorption. .

〔Effect of the invention〕

Films using the composition obtained in the present invention have excellent transparency, a good balance between slip properties and printability, and blocking properties that are within the practical range.

〔Example〕

Among the ingredients listed in Table 1 below, (al,
(b) and other components were mixed in a Henschel mixer, and the mixture was further added with component (c1) and pelletized at a temperature of 230°C in an extruder with a screw diameter of 35 mm and L/D 28. A composition was prepared.

This composition was processed into films using the following three methods.

(i) Film processing method (11) A linear air-cooled inflation extruder for ethylene polymer using a single air slit air ring (40 mm diameter, screw L/D 18) and a spiral type Gui 75
Using 1 layer diameter (lip width 3 times), extrude at 200°C to a film thickness of 30μ. At this time, the blow ratio was adjusted to 2.0.

(ii) Film processing method (2) The composition is processed using a double air sliver nodonia link.
Perform the same procedure as for the air cooling inflation above.

(iii) Film processing method (3) The composition was passed through an air-cooled inflation extruder (40 diameter, screw L1) using a single air slit air link.
022) and a spiral die with a diameter of 1001 m (lip width 0.8 mm) at 180° C. to a film thickness of 30 μm. At this time, the blow ratio was adjusted to 1.5.

The quality of the film thus obtained was evaluated on the following items. The measurement method is as follows.

The evaluation results are shown in Table 2.

The melt flow rate (MFR) is based on ASTM D1.
238 (190°C), and the flow ratio was determined according to JIS K7210-1975 using a melt indexer at 190°C based on the following formula.

The average particle diameters of silica, zeolite and talc are values determined by the Coulter Counter method (dispersion method is 28KC ultrasonic wave for 5 minutes, using 0.01% sodium hexametaline phosphate).

Synthetic silica is Thyroid 66, and zeolite is C8100.
was used.

(1) Haze Measured in accordance with ASTM D1003-61.

(2) Light scattering index (LSI) The formed film was kept at 23°C ± 2°C and 50 ± 5% RH for more than 24 hours, and after adjustment, the LSI meter EvanceElect
(manufactured by Roselenium) to measure the light scattering index.

(3) Blocking molded film at high temperature (45℃) and high load (50g/c+
After promoting film adhesion for 24 hours under
Tensile speed 500 m/mi using Schopper type tensile testing machine
It is expressed as the maximum stress (g/locmz) required to shearly peel off the film adhesive surface 10e11'' under conditions of n.

(4) Static friction coefficient Measured in accordance with ASTM D1894.

(5) Wetting tension Measured in accordance with ASTM D2578-67.

(Margin below)

Claims (1)

[Claims] Contains each of the following components (a) to (c), 100% of component (a)
A resin composition for extrusion molding, characterized in that component (b) is blended in a proportion of 0.01 to 1 part by weight and component (c) is blended in a proportion of 0.01 to 1 part by weight based on parts by weight. (a) Density 0.9 produced using Ziegler catalyst
10~0.940g/cm^3, melt flow rate 0
．． Ethylene copolymer with a comonomer content of 01 to 20 g/10 minutes and a comonomer content of 1 to 10% by weight (b) Zeolite with an average particle size of 20 μ or less (c) Organic amide compound