JPS5938976B2 - improved composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides polyolefin-based polyolefins having many characteristics such as excellent extrusion moldability, heat-sealing properties, impact strength properties, tensile strength properties, flexibility, transparency, heat resistance, and cold resistance. A composite composition is provided.

Specifically, a copolymer with ethylene selected from the group consisting of a monomer copolymerizable with ethylene: a vinyl ester, an aliphatic unsaturated monocarboxylic acid, and an alkyl ester of the monocarboxylic acid, preferably ethylene. -Vinyl acetate copolymer (1), specific ethylene/α-olefin copolymer elastomer (B), and (1) any one of crystalline polypropylene, high-density polyethylene, and crystalline polybutene-1, or a mixed polymer thereof ( This is a molding composition consisting of a mixed composition with C). Although these are not particularly limited, they are useful as compositions constituting at least one layer of a single layer and a composite layer for film forming.

Conventionally, in order to improve various properties of crystalline polypropylene (hereinafter abbreviated as PP), especially thermal stability, strength at low temperatures, impact resistance, etc., ethylene pyrene copolymer rubber (hereinafter referred to as EPR) has been used. Method of mixing one part of (abbreviated):
Japanese Patent Publication No. 35-7088, Japanese Patent Publication No. 36-15042, Japanese Patent Application Laid-Open No. 52-78977, etc. have been proposed.

However, with these methods, the compatibility of PP(!I■EPR) is not necessarily good.5 When processed into a thin film, it becomes uneven and fluffy, the surface becomes rough, the optical properties deteriorate greatly, and the strength deteriorates. Also, in order to improve these even a little, a method of further mixing amorphous atactic polypropylenes: JP-A-49-1999-
No. 112946, Japanese Unexamined Patent Publication No. 48-96638, etc. have been proposed. All of these are based on PP and have been improved, but they still have problems when made into thin films. The purpose and characteristics of the present invention are excellent extrusion moldability, especially improved film processing stability, heat sealing properties, various strength properties, flexibility, transparency, heat resistance, cold resistance, and stiffness (modulus of elasticity) of molded products. The object of the present invention is to provide a relatively soft composition, preferably a film composition, which has improved properties such as the following.

More specifically, (1) one of the purposes is (4) a monomer copolymerizable with ethylene; vinyl ester, aliphatic unsaturated monocarboxylic acid, alkyl ester of said monocarboxylic acid; At least one copolymer with ethylene, (B) is an elastomer rerandom copolymer consisting of an ethylene-α olefin copolymer and having a density of 0.91y/~ or less, and a melt index of 0.
．． 1 to 10 thermoplastic elastomers (B1') or ethylene-α-olefin copolymer rubber (B2). (C) is a hard component: crystalline polypropylene (C1). Crystalline polybutene-1 (C2). At least one polymer selected from the group consisting of high-density polyethylene (C3), in which the ratio of each component is 0.90≧B/(A+B)≧0.05, and 2.
The above (.A) where 0≧[/(A+B)≧0.05 and (
Mixed components of B) and (C) (However, (B2) and (C1), (B2) and (C3) and (B2) in (B) and (C)
) and (excluding the case of (C1) + (C3)}), and as described later, the (A) component is preferably an ethylene monovinyl acetate copolymer and the (B) component is ethylene. A random copolymer of 1-alpha olefin, or a random copolymer with a small amount of diene component oriented in addition to ethylene-alpha olefin, with a melt index of 0.1 to 1.
This thermoplastic elastomer is supplied in the form of 0 pellets.

Here, regarding each component, the polymer (A) used in the present invention is a polymer with relatively low crystallinity that is intermediate between hard and soft, and includes monomers copolymerizable with ethylene, vinyl ester,
It is a copolymer with ethylene selected from the group consisting of aliphatic unsaturated monocarboxylic acids and alkyl esters of the monocarboxylic acids, and these include ethylene monovinyl acetate copolymers,
Ethylene-ethyl acrylate copolymer (EEA
), ethylene-methacrylic acid methyl ester copolymer (abbreviated here as EMMA), ethylene-acrylic acid copolymer (herein abbreviated as EAA), ethylene-methacrylic acid copolymer, etc. The amount of monomers other than ethylene in these copolymers is 3 to 30 weight (Wt)
%, preferably 5 to 25 wt%, more preferably 7 to 25 wt%
If the amount of 25 wt (Fb) is less than 3 wt %, the sealability, flexibility, transparency, strength characteristics, etc. will be poor.

Moreover, if it exceeds 30 wt%, extrusion processability and mixability with other components will be poor, and when T is added to the film, the surfaces will tend to block against each other, causing problems in handling.
Also, the melt index is 0.2 to 10, preferably 0.
It is 2-10, preferably 0.3-5. If it is less than 0.2, there will be problems in the mixability and extrudability of the raw materials, and if it is more than 10, the strength as a base material will be insufficient and it will be easy to tear during stretching, which is undesirable.

Among the above, the most preferred is ethylene monovinyl acetate copolymer (hereinafter abbreviated as EVA).

Next, thermoplastic elastomer (B) consisting of ethylene and α-olefin copolymer has ethylene and 3 to 12 carbon atoms.
one or more α-olefins selected from α-olefins of
It refers to a soft copolymer with olefin, and in some cases, it may be further copolymerized with a small amount of a hydrocarbon having a polyene structure, such as synchropentadiene, 1,4-hexadiene, ethylidene norbornene, etc. good.
Examples of α-olefins include propylene, butene-1, hexene-1, heptene-1,4-methyl-1-benzene, and octene-1, with propylene and butene-1 being preferred. The ethylene content of the copolymer is 20 to 93 mol%, preferably 40 to 90 mol%, more preferably 6
It ranges from 5 to 88 mol%. The properties of these copolymers are that the density is 0.91t/Crii or less, preferably Icat
Softening point [ASTM Dl525 (value for 1 kg load)] is 8
0°C or less, more preferably 70°C or less, and generally ranges from substantially amorphous in a rubbery region to low partially crystalline with a degree of crystallinity (X-ray method) of about 30 (!) or less. This shall also include things. Preferred is a copolymer of ethylene and propylene or butene-1, or a copolymer containing a small amount of a compound having a diene structure, such as a random copolymer polymerized with a vanadium compound and an organic aluminum compound catalyst. A copolymer thermoplastic elastomer with a melt index of 0.1 to 10, preferably 0.2 to 6, which is not block-like like general non-vulcanized rubber and does not cause cold flow. Preferably, the material is supplied in the form of pellets and has sufficient thermoplasticity so that it can be extruded into a film even when used alone. Next, the polymer (C) is composed of relatively hard and relatively high crystallinity components, such as crystalline polypropylene, high density polyethylene, and high molecular weight crystalline polybutene-1 (hereinafter referred to as IPP, HDPE, and PB-1, respectively). ).

These preferably consist of relatively hard polymers with a VlCat softening point of 100° C. or higher. Crystalline polypropylene, which is one of the polymers (C), refers to crystalline polypropylene with high isotacticity that is usually commercially available. or other α-olefins are preferred. Or they may be mixed arbitrarily. In addition, high-density polyethylene has a density of 0.935 (7/CTii) or higher, which is commonly commercially available.
Low pressure polyethylene with a melt index of 0.1
to 10, preferably about 0.2 to 7, preferably including a copolymer, and the content of ethylene is 93 mol% or more, preferably about 95 mol%.

If the melt index is less than 0.1, there will be problems with mixing properties and optical properties during processing, and if it is more than 10, the strength of the base material will be impaired, which means that the processability during film formation will deteriorate. Undesirable. In addition, polybutene-1 is crystalline with a butene-1 content of 93 mol% or more and has a high molecular weight that also includes copolymers with other monomers. For the same reason, those with a melt index of 0.2 to 10 are preferred. Among the above, it is preferable to mainly use crystalline polypropylene. It is more preferable to add the above-mentioned polybutene-1 to crystalline polypropylene, and a mixture of polypropylene and high-density polyethylene may also be used. Other hard polymers that have appropriate compatibility and dispersibility and meet the purpose of the present invention may also be used. The composition of the present invention is composed of a mixed composition of each of the above components (5), (3), and (C), and the range of these amounts is preferably 0.90≧B/in terms of weight ratio.
(A+B)≧0.05 and 2.0≧C/(A+B)≧
0.05, more preferably 07 [skewer/(A+B
)≧0.07 and 1.5°C/(A+B)≧0.10, more preferably 0.50≧B/(A+B)≧0
．． 10 and 1.0≧°C/(A+B)≧0.10, more preferably 0.30≧B/(A+B)≧0.
10 and 0.7≧C/(A+B)≧0.10.

If the amount of the soft component (self) mixed is small, the mixture will not exhibit a synergistic effect, and the moldability, optical properties, and mechanical strength will decrease. The above range is preferable since the product tends to block and the sealing properties etc. tend to deteriorate.
The hard component (C) is the tensile/impact strength, heat resistance,
It synergistically improves extrusion moldability, elastic modulus, and heat sealing range with other ingredients, and has a particularly large effect on heat resistance, extrusion moldability, elastic modulus, heat sealing range, etc., and the effect is greater when the mixing amount is small. For example, the thickness deviation due to inflation processability and flow characteristics within the die increases, the effect of improving heat sealing range and strength decreases, and the expected value of heat resistance also decreases.

If the amount is too large, extrusion moldability, transparency, flexibility, impact strength, etc. will deteriorate, so it is preferably within the above range. Further, the melt index of these mixtures is usually 0.2 to 10. Here, component (4) consists of a specific ethylene copolymer among the aforementioned three components (A), (B), and (C).
Preferably, it is the main component in the mixture.

Mixing only component (A) and component (C) of the three components is usually
Mixability and compatibility are poor, and the synergistic effect described above is difficult to achieve, but when component (8) is added, these drawbacks are significantly improved.

These reasons are due to the characteristics of ethylene contained in component (4), the structure related to polar functional groups, delicate interactions with other components, and complex interactions such as the crystal structure of the mixture and the dispersion state of the mixture. This seems to be due to the effect.

For example, in the case where the component is mainly composed of ingredients, when the above-mentioned components are dry blended in the form of pellets and melt-kneaded and extruded using an extruder with excellent kneading ability to form a molded product, the components dispersed in component (4) Component (B) inside or near the surrounding area of C)
) may be complicatedly distributed and interacting with each other. Depending on the molding conditions, for example, when these are processed into films or other molded products and given fluidity and orientation, their shapes become different. For example, the above mixture is extruded at a relatively high temperature of 230 to 260°C through a die for films, sheets, etc. having a small slit, for example 1.5 mm, extruded as it is or by applying a certain draw ratio, and then rapidly cooled and processed into a film. In this case, it depends on the amount of hard component (C), but for example, 30wt.
In the case of mixing %I-PP, the component (01-P
P has a structure in which its dispersed particles are oriented in the flow direction in a fibrous manner within the main component, as if it were reinforced with glass fibers, and it may exhibit significantly improved properties such as strength. It appears to be. The composition of the present invention can be freely used as a molded product, a film, or for other adhesive purposes, and is not particularly limited, but it is preferable to use it as a film. The film can be formed by a method such as an inflation method such as a water cooling method, a method of forming a film by a method such as a casting method using a T-die, or a method of biaxially stretching these.

In addition, when molded as a multilayer composite as at least one of its constituent layers, it can be used as a film with processing stability, strength, sealing properties, and optical properties, and as an adhesive.
It is also preferred for the outer layer. Furthermore, it has very good processability and is convenient for processing into molded objects, such as films, which have been given a high degree of cold orientation. Further, as a preferable example, the additive (D) in the composition of the present invention is a normal liquid with a boiling point of 200°C.
A small amount of 0.3 to 5% by weight of the above nonionic surfactants,
Preferably, when 0.5 to 3% by weight is mixed, more desirable properties can be imparted synergistically. These nonionic surfactants include polyhydric alcohols such as glycerin, sorbitol, pentaerythritol, and polyglycerin, linear saturated fatty acids with an alkyl group of 5 to 13 carbon atoms, or linear saturated fatty acids with an alkyl group of 17 to 21 carbon atoms. Examples include esters with chain unsaturated fatty acids, such as diglycerin monooleate, and polyoxyethylene alkyl phenyl ethers, such as polyoxyethylene nonyl phenyl ether or polyoxyethylene octylphenyl ether. As the polyoxyethylene fatty acid esters, esters with the aforementioned fatty acids to which polyoxyethylene of 3 to 10 units of ethylene oxide is added are preferable, and these may be used alone or in combination.

When made into a film, these exhibit anti-blocking, antistatic and anti-fogging effects and are suitable as packaging films.

In addition, these additives are easily dissolved in any of the components in the mixed resin component, and they have the effect of gradually penetrating and bleeding out from the inner layer to the surface layer, and are generally not suitable for olefin-based polymers. The low-molecular components that tend to be present are immediately removed, and the surface does not become sticky or other negative effects, and even if the surface is washed away, it remains effective for a long time. It also has favorable properties such as a plasticizing effect. In addition, as another addition (UE) to the mixed composition of the present invention, 1 to 5% by weight, preferably 1% by weight, of mineral oils that are liquid at room temperature, such as those selected from paraffinic, isoparaffinic, and naphthenic oils.
When ~3% by weight is included, a mixed matrix containing a large amount of lipophilic components such as component (B) in the mixed composition is formed, and as mentioned above, the lipophilic components are immediately spilled onto the surface without causing contamination. Polyolefin can be plasticized.

Moreover, when the above-mentioned additives 1 and (E) are used in a mixture of appropriate amounts, it becomes even more characteristic. As described above, it is possible to apply for a plasticizing effect, which has not been achieved with polyolefin polymers until now, by incorporating various additives based on the difference in affinity in the composition by creating a mixed matrix-like composite composition. .

In particular, with highly crystalline HDPE, PP, etc., even a small amount of additives will mostly come out on the surface and cannot be mixed uniformly, but the composition of the present invention is different in this respect.

In addition, films made with these compositions or additives added thereto can have an appropriate film stiffness and have a plasticized effect. If you put it together by hand, it will be compressed into a small size, and even if you loosen your hands, it will remain the same shape.On the other hand, a film made of EVA alone will not be able to be rolled up into a small size, and if you loosen it, it will instantly return to its original shape. It can be made into a film with properties similar to those made of plasticized PVC, and can be used, but is not particularly limited, to shrink wrapping films, stretch packaging films, other packaging films, agricultural films,
As a multilayer film, a barrier film by adding a via layer, a shrink packaging film thereof, or a multilayer film with other types of resins can be used. The mixture of the present invention may also be mixed with other plastic materials. A specific example will be described below using a film as an example, but the present invention is not limited thereto.

Example 1 EVA (vinyl acetate group content: 10% by weight, melt index: 0.8) (a1): 65 parts by weight and ethylene-α
Olefin copolymer elastomer (α-olefin contains 15 mol% of propylene, ethylidene norbornene 2
Melt index 0,4 by random copolymerization of weight%
5. Vikatsu softening point 40℃ or less, density 0.88y/CT
l) (b1): 15 parts by weight, crystalline polypropylene (melt index 1.0 density 0.887/d1 copolymerized with 4% ethylene, Vikat softening point 143°C) (c1
): 20 parts by weight were mixed and plasticized and kneaded with a 65 mm diameter L/D-37 mixing head type screw at a maximum temperature of 240°C in the cylinder part, and a 100 mm diameter slit of 1.0 m77! Extrude from the annular die,
By introducing nitrogen into the interior, it is inflated and rapidly cooled to a diameter of 400mI! A uniform film with a thickness of 50 μm was obtained.

This film was continuously wound up into a roll. (
Run Waterfall 1) Finished≧? ? (a1) (A2) -Jyobuki|1 (a-3--1 β-!- (A4) (A5) --1 (A6) -1 (-B4) -nu''- )-5 - :'. :-Riejin-Ji71-]- The film forming processability was good and the film could be formed stably, and the thickness deviation in the width direction was ±2.5%, and the variation in the folding width was R: 2 mT.
It was uniform with IL.

The characteristics of this film were as follows. V. --． Otoripi 0▼Hibiki-111? -IV〒〒°C, wide range and heat resistance.

Here, Haze is determined by ASTM DlOO3-52 method, tensile strength is determined by ASTM D882-67 method, and Dart strength is determined by AST.
It was measured according to the MDl7O9-67 method, and the elastic modulus is the value obtained by converting the stress at 2% elongation to the stress at 1009b elongation. 1 (seal width: 5m0) This shows the range that can be preferably sealed by changing the temperature,
The lower limit is the temperature at which it peels and cannot be sealed with a constant strength, and the upper limit is the temperature at which it melts and breaks due to heat, indicating the heat resistance at which it is impossible to maintain a constant sealing strength.

In addition, the pressing force at the time of sealing was 1 kg/d, and the time was adjusted as appropriate. Example 2 A film was prepared using the composition shown in Table 1 in the same manner as in Example 1, and the obtained properties are shown in Table 2.

(However, FunAl). Only No. 11 is in the form of a block (kneaded with other ingredients using a B3 tread kneader and repelletized to form pellets)? ? ? ? ? ? ? ? ? ? ? ? ? ? ?
? ? --=? ? ? ? ? 20152015-yen-1 15
-40 - "11] 201 35T-201 2!] (-o1] 11513011 - 112511 [,51") In both cases, the process stability of film formation was good, and uneven thickness of the film (occurred due to die structure, etc. ), the improvement effect on strength is large, and each heat sealing range is wide11
The temperature was 0 to 260°C, and the sealing strength was also excellent.

Defects such as holes caused by heat were less likely to occur. Also, in terms of cold resistance, the film did not become hard or easily tear at (-3'C). In addition, Ru
With a composition of n/F62 and a die slit of 2.0 mm, 260
A film was formed in the same way at an extrusion temperature of ℃, with a diameter of 100φ, and the draw ratio was increased as much as possible to obtain a 100μ film, and the tensile modulus (vertical/horizontal) was measured to be 4.
When this product with a K9/d of 0/19 (K9/d) was observed under a phase contrast microscope, it was observed that the polypropylene components were finely fibrous and oriented in the flow direction (vertically). This film has a Dart impact strength of 37kg-? It was a strong thing. Further, as a comparative example, in the case of EVA alone, the elastic modulus was 5/5 (K9/Md). Example
The composition of 3Run Standard 1 was used as the inner layer and outer layer, and the middle layer was made of polyvinylidene chloride (copolymer modified with vinyl chloride), extruded through a three-layer die, subjected to inflation, and cooled. Outer layer: 20μ, middle layer: 10
A film with a thickness of 30 μm and an inner layer was obtained.

This film has excellent heat sealability: [110-28
0℃], heat seal strength: 3 kg/15 mm width, and tensile strength: 4.0/3.6 (Kg
/Md), elastic modulus: 23/18 (Kg/Md),
It has good waist and flexibility, and Dart impact strength: 361<
g.? The film also had excellent cold resistance.

In addition, the acidity permeability is 20 (Cc/24hr1atm.m
”).Example 4 The composition of Run Wash 1 was melted and plasticized using the same extruder as in Example 1, and it was added as a liquid additive (D1) from the middle of the extruder.
A composition in which 1.5% by weight of diglycerin monooleate was injected and kneaded was similarly extruded to form a uniform 14μ film at a blow ratio of 4.

This film has a tensile strength of 4.5/4.2 (K9/Mi)
Elongation at 410/470 (A) Dart impact strength: 32
K9/mil, elastic modulus: 15/10 (K9/Mil)
, Haze: 1.3%, it has sufficient elongation and flexibility as a stretch packaging film, has good fit and adhesiveness to foreign object molds, and also has a moderate stiffness, and can be used with a hot plate. It had excellent sealing properties and heat resistance. As a comparative example, I tried doing the same with EVA alone, but the tensile strength of the film was 2.8/2.7 (Kg/M
d) Dart impact strength: 13kg・? It easily tears during packaging, and excessive additives bleed out onto the surface, making it sticky. Also, when trying to seal the overlapped film with a hot plate during packaging, large holes occur, resulting in poor sealing performance and heat resistance. This was unsatisfactory, and the stiffness of the film during packaging (related to elastic modulus: 3/2 (K9/Md)) was weak, resulting in disadvantages in handling and other aspects. Example 5 In Example 4, mineral oil (specific gravity: 0.885, Saybolt viscosity: 350) was further added as a liquid additive (E).
A similar film was obtained by dissolving 1.5% by weight of rosin tester and hydrogenated rosin glycerin ester to give a final amount of 0.7% by weight.This film had a tensile strength of 3. .8/3.5 (Kg/TlLd
), elongation: 460/480 gloss, Dart impact strength: 29
1<g・? and elastic modulus: 12/9 (K9/Md), Ha
ze: 0.9(1), it is flexible and pliable, and can be wrapped under excellent conditions during stretch packaging.In particular, even when the same film is stacked many times, it remains tightly fixed, and it can be made using only EVA. Compared to other films that tear during packaging, tear during sealing, and quickly lose their elasticity due to rubber-like elasticity when the same films are stacked together, this film has many surfaces that are equivalent to or better than plasticized PVC films. It was hot.

Comparative Example 1 A film having the composition shown in Table 3 below was obtained in the same manner as in Example 1.

Claims (1)

[Scope of Claims] 1(A) is at least one monomer copolymerizable with ethylene; a vinyl ester, an aliphatic unsaturated monocarboxylic acid, an alkyl ester of the monocarboxylic acid; A seed copolymer, (B) is an elastomer consisting of an ethylene-α olefin copolymer and has a density of 0.91 g/cm^3 or less; a random copolymer and a thermoplastic elastomer with a melt index of 0.1 to 10 (B_1 )
, or ethylene-α olefin copolymer rubber (B_2)
, (C) is a hard component; crystalline polypropylene (C_1)
, at least one polymer selected from the group consisting of crystalline polybutene-1 (C_2), and high-density polyethylene (C_3), and the mixing ratio of each component is 0.90≧B/(A+B)≧0.05 And 2.0≧C
/(A+B)≧0.05, the above (A) and (B) and (
Mixture component of C) (However, (B_2 in (B) and (C)
) and (C_1), (B_2) and (C_3) and (B_
An improved composition mainly consisting of 2) and {(C_1)+(C_3)}).