JPS5856579B2 - Method for producing modified polypropylene composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to polyolefin or nylon, polyester, saponified ethylene-vinyl acetate copolymer, glass,
The present invention relates to a method for producing modified polypropylene that has good adhesion to polar substances such as metals.

In general, polypropylene has mechanical properties, transparency, moldability,
Although it is used in a wide range of fields due to its excellent hygiene properties, it has the disadvantage of poor adhesion to polar substances because it is non-polar.

Various proposals have been made to improve this adhesiveness.
One such method is to graft a monomer consisting of an unsaturated carboxylic acid or a derivative thereof to polypropylene.

Grafting methods include a method of reacting in a solution state (e.g., Japanese Patent Publication No. 15422/1972), and a method of reacting in a slurry state (e.g., Japanese Patent Publication No. 18144/1973).
, a method of reacting in a molten state (for example, Japanese Patent Publication No. 43-27
421) etc.

Among these methods, the method of reacting in a molten state using an extruder is advantageous because it is easy to operate, but unreacted monomer remains in the obtained modified polypropylene, and if there is a large amount of it, it may cause adhesion. There are drawbacks such as insufficient properties and the generation of bubbles during molding of sheets, films, blow molding, etc.

Therefore, methods such as the dissolution-reprecipitation method and the solvent extraction method (Japanese Patent Application Laid-open No. 54-99193) have been proposed as methods for removing unreacted monomers, but these methods do not use large amounts of solvents or poor solvents. It has the drawbacks of being complicated to operate and being expensive.

The present inventors previously conducted various studies on methods for removing unreacted monomers remaining in modified polypropylene obtained by a melt-kneading method using unsaturated carboxylic acids or derivatives thereof, and found that It has been discovered that heating polypropylene at 60°C or higher significantly reduces unreacted monomers, suppresses foaming during forming into sheets, films, blow molding, etc., and improves adhesion to polar substances. (Patent application 170896/1989
issue).

On the other hand, in order to improve the adhesion of modified polypropylene grafted with unfoamed carboxylic acids, a method of adding a rubbery substance to the modified polypropylene has been proposed (for example, Japanese Patent Publication No. 5'4-40112, Kaisho 52-803
No. 34).

However, since a large amount of unreacted monomer remains in the modified polypropylene produced by the melt-kneading method, simply adding a rubbery substance to the modified polypropylene will hardly improve the adhesion.

On the other hand, since modified polypropylene produced by the melt-kneading method generally has a low grafting rate, a method has been proposed in which a rubber-like substance is added in advance to improve the grafting rate by the melt-kneading reaction to improve adhesion (for example, Kosho 55-5
No. 766, Special Publication No. 55-18251).

However, since the modified polypropylene produced by this method also has a large amount of unreacted monomer remaining, not only does it have insufficient adhesive properties, but it also causes air bubbles to form when molded into films, sheets, blow molding, etc. There are drawbacks.

In addition, modified polypropylene obtained by melt-kneading with a rubber-like substance added in advance will not adhere to polar substances unless the amount of grafted unsaturated carboxylic acid is about 0.15 mol% or more even after sufficient heat degassing. Not sexual enough.

When the amount of unsaturated carboxylic acid grafted is about 0.15 mol% or more, heating and deaeration can suppress foaming due to unreacted monomers during molding immediately after heating, but unsaturated carboxylic acid has strong hygroscopicity. If left for a long period of time, it will absorb moisture from the air and foaming will occur during molding.

Therefore, a modified polypropylene that does not cause foaming during molding due to moisture absorption, has a low grafting amount of unsaturated carboxylic acid, and has good adhesion to polar substances has been desired.

In view of the above, the present inventors have conducted various studies on a method for producing modified polypropylene that has a low grafting amount of unsaturated carboxylic acid and has good adhesion to polar substances using the easy-to-operate and low-cost melt mixing method. As a result, it was surprisingly found that modified polypropylene 90 obtained by the melt-kneading method
By mixing 10 to 50 parts by weight of an ethylene-α-olefin random copolymer with ~50 parts by weight and heat-treating at a temperature of 60'C or higher, a material with low grafting amount of unsaturated carboxylic acid and excellent adhesive properties can be obtained. We have discovered that it is possible to produce a good modified polypropylene composition, and have arrived at the present invention.

The present invention involves mixing 90 to 50 parts by weight of modified polypropylene obtained by melt-kneading a mixture of polypropylene, an unsaturated carboxylic acid or its derivative, and an organic peroxide, and 10 to 5 parts by weight of an ethylene-α-olefin random copolymer.
After melting and mixing the mixture with 0 parts by weight and pelletizing, 6
This is a method for producing a modified polypropylene composition, which is characterized by heat treatment at a temperature of 0° C. or higher for 90 minutes to 10 hours.

The modified polypropylene composition obtained by the production method of the present invention can be obtained by simply heating modified polypropylene at 60°C or higher, or by simply adding an ethylene-α-olefin random copolymer to the modified polypropylene and melt-kneading the modified polypropylene. In comparison, adhesion is significantly improved.

Although the mechanism of action of the adhesive improving effect of the present invention is not clear, the modified polypropylene composition
It is presumed that this is because the heat treatment at 0° C. or higher causes some structural changes as well as a decrease in unreacted monomers.

Therefore, it is also effective to perform the heat treatment at 60° C. or higher more than to reduce unreacted monomers.

The polypropylene used in the present invention is not particularly limited, and includes homopolypropylene, propylene ethylene random copolymer, propylene-ethylene block copolymer,
Copolymers of propylene and α-niolefin, mixtures thereof, and the like are used.

Examples of unsaturated carboxylic acids used in the present invention include acrylic acid, methacrylic acid, maleic acid,
Examples of derivatives of unsaturated carboxylic acids include acid anhydrides, esters, amides, imides, metal salts, etc., such as maleic anhydride, citraconic anhydride, and citraconic anhydride. itaconic acid, methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, butyl acrylate, butyl methacrylate,
Glycidyl acrylate, glycidyl methacrylate, monoethyl maleate, diethyl maleate, monomethyl fumarate, dimethyl fumarate, monomethyl itaconate, diethyl itaconate, acrylamide, methacrylamide,
Maleic acid monoamide, maleic acid diamide, maleic acid-N-monoetheramide, maleic acid-N-N-diethylamide, maleic acid-N-monobutylamide, maleic acid-N-N-dibutylamide, fumaric acid monoamide, fumaric acid acid diamide, fumaric acid-N-monoethylamide, fumaric acid-N-N-diethylamide, fumaric acid-N-
Examples include monobutylamide, fumaric acid-N-N-dibutylamide, maleimide, N-butylmaleimide, N-phenylmaleimide, sodium acrylate, sodium methacrylate, potassium acrylate, potassium methacrylate, and the like.

Among these, it is most preferable to use maleic anhydride.

The amount of unsaturated carboxylic acid or its derivative added is not particularly limited, but may be determined depending on the amount of graft reaction of unsaturated carboxylic acid to polypropylene and the amount of unsaturated carboxylic acid in the modified polypropylene composition.

It is usually added in an amount of 0.01 to 20 parts by weight, preferably 0.1 to 5 parts by weight, per 100 parts by weight of polypropylene.

Further, in the present invention, an organic peroxide is used to promote the reaction between polypropylene and an unsaturated carboxylic acid or a derivative thereof.

Examples of organic peroxides include benzoyl peroxide, lauroyl peroxide, azobisisobutyronitrile, dicumyl peroxide, α・α′-bis(t-
7”Terperoxydiisoglobil)benzene, 2.5
-dimethyl-2,5-di(t-butylperoxy)hexane 2,5-dimethyl-2,5-di(t-butylperoxy)hexane-3, di-t-butylperoxide,
Examples include cumene hydroperoxide and t-butyl hydroperoxide.

The amount of organic peroxide added is not particularly limited, but is usually 0.
0.005 to 5 parts by weight, preferably 0.01 to 1 part by weight.

Furthermore, in the present invention, fillers such as talc, calcium carbonate, gypsum, and magnesium oxide; phthylated hydroxytoluene, butylated hydroxyanisole, tetrakis It may contain a heat-resistant stabilizer such as tumanyl) propionate comethane; a weather-resistant stabilizer; a lubricant; an antistatic agent; a nucleating agent; a pigment; a dye; an anti-blocking agent, and the like.

In the present invention, the above-mentioned polypropylene, unsaturated carboxylic acid or its derivative, and organic peroxide are sufficiently mixed in a tumbler, Henschel mixer, etc. The grafting reaction is carried out by melt-kneading at a certain temperature.

The method of melt-kneading is not particularly limited, but it can be carried out using, for example, a screw extruder, a Banbury mixer, a mixing roll, or the like.

The temperature and time of melt crosstalk vary depending on the decomposition temperature of the organic peroxide used, but generally it is 160 to 280°C.
A suitable time is 3 to 30 minutes, preferably 1 to 10 minutes at 170 to 250°C.

Note that the melt-kneading may be performed in an inert gas stream.

Next, in the present invention, it is necessary to mix an ethylene-α-olefin random copolymer into the modified polypropylene produced as described above.

The ethylene-α-olefin random copolymer used in the present invention is not particularly limited, and has an MPlo of 1 to 100.
P710 min, preferably 0.5 to 30 P/10 min, ethylene content 30 to 95% by weight, preferably 50 to 9
0% by weight is preferred.

As the ethylene-α-olefin random copolymer,
Ethylene-propylene random copolymer, ethylene-butene-1 random copolymer, ethylene-pendes-1 random copolymer, ethylene-3-methyl-butene-1 random copolymer, ethylene-hexene-1 random copolymer combination, ethylene-4-methylpentene-1 random copolymer, ethylene-ophtatecene-1 random copolymer,
Examples include ethylene-propylene-diene random copolymer.

The ethylene-α-olefin random copolymer may be used alone or in combination of different types.

Among the above-mentioned ethylene-α-olefin random copolymers, it is preferable to use an ethylene-butene-1 random copolymer or an ethylene-propylene random copolymer, which has a remarkable effect of improving adhesion.

In the present invention, the amount of the ethylene-α-olefin polymer copolymer added is 90% to 50% of the modified polypropylene.
The amount is 10 to 50 parts by weight, preferably 15 to 40 parts by weight to 85 to 60 parts by weight.

If the amount added is less than 10 parts by weight, the effect of improving adhesion is small, and if it exceeds 50 parts by weight, not only the adhesion but also the mechanical strength will decrease, which is not preferable.

In addition to modified polypropylene and ethylene-α-olefin random copolymer, unmodified polypropylene can also be mixed.

The addition ratio of unmodified polypropylene is 0 to 80 parts by weight per 100 to 20 parts by weight of modified polypropylene, preferably 10 to 80 parts by weight per 90 to 30 parts by weight of modified polypropylene.
It is 70 parts by weight.

Mixing of the modified polypropylene, the ethylene-α-olefin random copolymer, or, if necessary, the unmodified polypropylene, can be carried out using a tumbler, a Henschel mixer, or the like.

Next, these mixtures are melt-kneaded using, for example, a screw extruder, a Banbury mixer/mixing roll, or the like.

Furthermore, in the present invention, the pelletized product of the modified polypropylene composition produced as described above is heated at 60°C or higher.
It is extremely important to heat and degas preferably at a temperature of 100° C. or higher.

That is, by such heat treatment, the adhesiveness of the modified polypropylene composition of the present invention is significantly improved compared to conventional modified polypropylene compositions.

In particular, the modified polypropylene composition of the present invention exhibits good adhesion even when the amount of unsaturated carboxylic acid grafted is, for example, about 0.15 mol % or less, particularly 0.12 mol % or less, which does not cause foaming during molding.

Therefore, according to the present invention, a modified polyolefin composition with good adhesiveness that does not cause foaming during molding is provided.

When the heating temperature is 60° C. or lower, degassing takes a long time and is not practical.

Although the upper limit of the heating temperature is not particularly limited, it is preferably below the melting point of the modified polypropylene in order to prevent fusion of the modified polypropylene.

The heating degassing means may be a conventionally known method, such as an aeration band type dryer, a material agitation type dryer, a fluidized bed dryer,
The drying can be carried out using a flash dryer, a spray dryer, a rotary dryer, a drum dryer, a vacuum dryer, an infrared dryer, a far-infrared dryer, a micro dryer, etc., but a hot air dryer is preferably used.

Note that the degassing effect is further improved if heat drying is performed under reduced pressure.

The heating deaeration time is not particularly limited, but it may take a long time if the heating temperature is low and the modified polypropylene contains a large amount of unreacted monomers, and it may take a short time if the heating temperature is high and there are few unreacted monomers. That's fine.

Generally, the heating time is 10 minutes to 10 hours, and it is preferable to heat and degas so that the amount of unreacted monomer is 0.05 mol % or less.

The modified polypropylene composition obtained in the present invention not only has good adhesion to unmodified polypropylene, but also has good adhesion to polar substances such as metals, glass, nylon, polyester, and saponified ethylene-vinyl acetate copolymers. Shows adhesion.

Therefore, for example, (1) polar resin/modified polypropylene composition/polypropylene, (2) modified polypropylene composition/polar resin/modified polypropylene composition/polypropylene, (3) polypropylene/modified polypropylene composition/polar resin/modified polypropylene composition. It is possible to provide a laminate with good adhesion of polypropylene and the like.

Moreover, when these laminates are stretched, a composite stretched polypropylene film having excellent gas barrier properties, oil resistance, water impermeability and heat sealability is obtained.

EXAMPLES The present invention will be explained below with reference to Examples, but the present invention is not limited to these Examples.

Note that the various physical properties in this specification were measured by the following methods.

○Measured using MFI ASTM D 1238-52T at 230°C under a load of 2160P.

○Amount of maleic anhydride A film with a thickness of approximately 0.1 mm was formed by hot pressing, and the infrared absorption spectrum was measured. From the absorption peak intensity of maleic anhydride of 1780CIrL-1, the
The amount of maleic anhydride was determined using the calibration curve shown in Figure 2, Vol. 5, No. 274 (1968), p. 109.

The amount of maleic anhydride in the graft reaction is approximately 0.1 mr thick.
The amount of maleic anhydride was taken as the amount of maleic anhydride in the sample which was vacuum-dried at a temperature of 50° C. for 24 hours after extracting the film of No. n with acetone for 6 hours.

The amount of residual unreacted maleic anhydride was determined by subtracting the amount of graft-reacted maleic anhydride from the total amount of maleic anhydride.

O adhesive strength (T-peel strength) For adhesion with saponified ethylene-vinyl acetate copolymer, nylon, and polyethylene terephthalate, co-extrude them, cut them into 2-width pieces in the direction of cooling and solidification, and measure the T-peel strength. It was measured.

Adhesion to glass and aluminum was determined by wiping the glass plate and aluminum plate with xylene, sandwiching modified polypropylene between the two plates, melting at 250°C, pressing, cooling and solidifying, and peeling off by hand. The adhesive strength was measured by looking at the sample.

A T-die was attached to a 40 mm diameter extruder with an O tensile modulus of elasticity L/D = 20, and 2
A sheet with a thickness of 0.5 mm was extruded at 00°C, and the resulting sheet was cut into strips with a width of 1 cfIL in the MD force direction.
A tensile test was carried out at 1 minute in mm, and the tensile modulus was calculated from the initial slope.

Examples 1-4, Comparative Examples 1-2 MFI=1.3f/10min homopolypropylene 100
Parts by weight, 0.5 parts by weight of maleic anhydride, 2,5-dimethyl-2,5-di(t-butylperoxy)hexane (trade name: Kayahexa AD-40°C) 0.1 parts by weight, butylated hydroxy Toluene (trade name: BHT), 1 part by weight, and 0.1 part by weight of calcium stearate were mixed in a hexyl mixer for 5 minutes, and a 40-meter diameter with L/D = 24 was mixed.
Melt-kneading pelletization was performed at 220°C using an extruder.

The MFI of the obtained modified polypropylene is 34.5 y,
'i 0 min, total maleic anhydride amount is 0.197 mol%,
The amount of graft-reacted maleic anhydride was 0.082 mol%, and the amount of unreacted maleic anhydride was 0.115 mol%.

Next, this modified polypropylene was mixed with an ethylene-butene-1 random copolymer having an ethylene content of 80% by weight and an MFI = 6.4 P/10 min in the proportions shown in Table 1.
Melt-kneading pelletization was performed at 220° C. using a 407ILπφ extruder with /D=24.

Thereafter, these modified polypropylene compositions were heated and degassed at 150° C. for 3 hours using a constant temperature air dryer.

MFI of the obtained modified polypropylene composition, maleic anhydride content, saponified ethylene-vinyl acetate copolymer (
Table 1 shows the adhesive strength and tensile modulus with respect to saponified EVA (hereinafter also abbreviated as saponified EVA).

The adhesive strength with the saponified ethylene-vinyl acetate copolymer was determined as follows.

That is, the modified polypropylene composition was
A saponified ethylene-vinyl acetate copolymer (MF I = 19.5?/1o
minutes, ethylene content 45 mol%, saponification degree 99% or more) were extruded from a 30 mmφ extruder with L/D = 24 at 200 °C through a coextrusion T-die to obtain a modified polypropylene composition with a thickness of 0.5 mm. A coextruded sheet of saponified ethylene-vinyl acetate copolymer having a thickness of 0.2 mm was molded, and its T-peel strength was measured.

Note that these modified polypropylene compositions did not foam during molding even when left for a long period of time.

Comparative Example 3 The same procedure as in Example 2 was carried out except that heating and deaeration was not performed in Example 2.

Obtained modified polypropylene composition (7) MF I =
19.4 P/10 minutes, total maleic anhydride amount is 0.1
45 mol%, graft reaction maleic anhydride amount is 0.06
1 mol%, the amount of unreacted maleic anhydride is 0.084 mol%
The adhesive strength with saponified EVA was 0.

It also foamed during molding.

Comparative example 4 MF l-13L? /10 minutes homopolypropylene 80
Parts by weight, ethylene content 80% by weight, MFI=6.4?
/ 20 parts by weight of x-y-lene-phthene-1 random copolymer, 0.3 parts by weight of maleic anhydride, 1 part by weight of Kayahexa AD-40C, 1 part by weight of BHTo, 0.1 part by weight of calcium stearate. Mixed for 5 minutes with a Henschel mixer, melt-kneaded and pelletized at 220°C with a 40 mm diameter extruder with L/D = 24, and MF I =
17.3 P/10 min, total maleic anhydride amount 0.153
A modified polypropylene composition was obtained in which the amount of graft-reacted maleic anhydride was 0.113 mol % and the amount of unreacted maleic anhydride was 0.040 mol %.

Next, this modified polypropylene composition was heated and degassed at 150°C for 3 hours using a constant temperature air dryer, and MF I
= 14.5f/10min, total maleic anhydride amount 0.13
A modified polypropylene composition was obtained in which the amount of graft-reacted maleic anhydride was 0.110 mol%, and the amount of unreacted maleic anhydride was 0.028 mol%.

The adhesive strength between this modified polypropylene composition and saponified EVA was 0.

When this modified polypropylene was left as it was for 5 months, it developed a small crack during molding.

Example 6 MFI=0.5P/10min, ethylene content 1.0% by weight
100 parts by weight of propylene-ethylene random copolymer, 0.5 parts by weight of maleic anhydride, 0.1 parts by weight of dicumyl peroxide, 1 part by weight of BHTo, and 0.1 parts by weight of calcium stearate were mixed in a Henschel mixer for 5 minutes. Mix and use a 40 mm φ extruder with L/D=24 to
Melt-kneading pelletization was performed at ℃.

MF I of the obtained modified polypropylene = 3.2
P710 minutes, total maleic anhydride amount is 0.203 mol%,
The amount of graft-reacted maleic anhydride was 0.086 mol%, and the amount of unreacted maleic anhydride was 0.117 mol%.

The ethylene content is 80 parts by weight in this modified polypropylene.
20 parts by weight of an ethylene-butene-1 random copolymer with a weight percent of MFI-64i/'10 was mixed, and L/D=2.
Melt-kneading pelletization was performed at 220°C using a 40 mmφ extruder No. 4.

Next, this modified polypropylene composition was heated and degassed at 145° C. for 3 hours using a constant temperature hot air dryer.

MFI-3,5f of the obtained modified polypropylene composition
/10 minutes, the total amount of maleic anhydride was 0.073 mol%, the amount of graft-reacted maleic anhydride was 0.063 mol%, and the amount of unreacted maleic anhydride was 0.010 mol%.

40 m of this modified polypropylene composition with L/D=20
mφ extruder at 200℃, and nylon 6 L/D=
Co-extrusion T from 24 30 mm φ extruders at 250°C.
The mixture was coextruded through a die to form a coextruded sheet having a modified polypropylene composition layer of 0.5 mm thickness and a nylon 6 layer of 0.2 mm thickness.

Is the device strength 4300? /2cm.

Comparative Example 5 The same procedure as in Example 6 was carried out except that heating and deaeration was not performed in Example 6.

MF I = 3 of the obtained modified polypropylene composition
．． 5 P/10 minutes, the total amount of maleic anhydride was 0.175 mol%, the amount of graft-reacted maleic anhydride was 0.064 mol%, the amount of unreacted maleic anhydride was 0.111 mol%, and the amount of maleic anhydride was 0.111 mol%. The adhesive strength was O.

Comparative Example 6 MFI=0.5te/10min, ethylene content 1.0% by weight
80 parts by weight of propylene-ethylene random copolymer,
20 parts by weight of ethylene-butene-1 random copolymer with ethylene content of 20% by weight, MFI = 6.4S'/10 minutes,
0.3 parts by weight of maleic anhydride, 0.1 parts by weight of dicumyl peroxide, 1 part by weight of BHTo, and 0.1 parts by weight of calcium stearate were mixed in a Henschel mixer for 5 minutes, and a 40 mmφ extruder with L/D = 24 was used. Melt-kneading pelletization was performed at MFI = 2.6 f/10 min, total amount of maleic anhydride 0.197 mol%, amount of graft-reacted maleic anhydride 0.135 mol%, amount of unreacted maleic anhydride 0.
A modified polypropylene composition containing 0.062 mol % was obtained.

Next, this modified polypropylene composition was heated and degassed at 145°C for 3 hours using a constant temperature air dryer, and MFI=
2.3 f/10 min, total maleic anhydride amount o, 14 s
A modified polypropylene composition was obtained in which the amount of graft-reacted maleic anhydride was 0.128 mol % and the amount of unreacted maleic anhydride was 0.020 mol %.

The adhesive strength between this modified polypropylene composition and nylon 6 was 150P/2CIrL.

Example 7 MF I = 1.2 f/10 min, ethylene content 2.
6% by weight propylene-ethylene block copolymer 10
0 parts by weight, 0.5 parts by weight of maleic anhydride, 0.2 parts by weight of benzoyl peroxide, 1 part by weight of BHTo, and 0.1 parts by weight of calcium stearate were mixed in a Henschel mixer for 5 minutes, and L/D = 24. Melt-kneading pelletization was performed at 190° C. using a 40 mm extruder.

MFI of the obtained modified polypropylene = 30.5P/1
At 0 minutes, the total amount of maleic anhydride was 0.233 mol%, the amount of graft-reacted maleic anhydride was 0.092 mol%, and the amount of unreacted maleic anhydride was 0.141 mol%.

The ethylene content is 70 parts by weight in 80 parts by weight of this modified polypropylene.
Mixing 20 parts by weight of ethylene-propylene random copolymer with weight part %, MFI = 5.3 P/10 minutes,
Melt mixed wire pelletization was performed at 220° C. using a 40 m7 ILφ extruder with L/D=24.

Next, this modified polypropylene composition was heated and degassed at 150°C for 3 hours using a constant temperature hot air dryer, and MF I = 1
6. IP/10 min, total maleic anhydride amount 0.087 mol%, graft reaction maleic anhydride amount 0.071 mol%
A modified polypropylene composition containing 0.016 mol % of unreacted maleic anhydride was obtained.

40 m of this modified polypropylene composition with L/D=20
mφ extruder at 200°C, and polyethylene terephthalate was extruded from a 3o1rL11Lφ extruder with L/D=24 at 270°C through a coextrusion T-die, so that the thickness of the modified polypropylene composition layer was 0.5 mm, and the polyethylene terephthalate layer was A coextruded sheet with a thickness of 0.2 mm was made and the adhesive strength was measured and it was found to be 4501/2c1.
It was rL.

Comparative Example 7 The same procedure as in Example 7 was carried out except that heating deaeration was not performed in Example 7.

MFI of the obtained modified polypropylene composition=25.3
P/10 min, total maleic anhydride amount is 0.208 mol%,
The amount of graft-reacted maleic anhydride was 0.079 mol %, the amount of unreacted maleic anhydride was 0.131 mol %, and the adhesive strength with polyethylene terephthalate was 0.

Comparative Example 8 MFI = 1.2 g/10 min, 80 parts by weight of propylene-ethylene block copolymer with ethylene content of 2.6%, ethylene content of 70% by weight, ethylene-propylene random with MFI = 5.3 V2O 20 parts by weight of copolymer,
0.3 parts by weight of maleic anhydride, 0.2 parts by weight of benzoyl peroxide, 11 parts by weight of BHTO, and 0.1 parts by weight of calcium stearate were mixed in a Henschel mixer for 5 minutes, and then mixed at 190°C in a 40 mmφ extruder with L/D=24.
Melt kneading pelletization was performed with MFI=16.7P/1.
A modified polypropylene composition was obtained in which the total amount of maleic anhydride was 0.210 mol %, the amount of graft-reacted maleic anhydride was 0.149 mol %, and the amount of unreacted maleic anhydride was 0.061 mol %.

Next, this modified polypropylene composition was heated and degassed at 150°C for 3 hours using a constant temperature air dryer, and MF I
= 14.2S'/10 minutes, total maleic anhydride amount 0.1
58 mol%, graft reaction maleic anhydride amount 0.137
A modified polypropylene composition with an amount of unreacted maleic anhydride of 0.021 mol % was obtained.

What is the adhesive strength between this modified polypropylene composition and polyethylene terephthalate? /2CIft.

Example 8 The modified polypropylene composition used in Example 2 was
After heating and degassing in the same manner as above, it was sandwiched between two glass plates wiped with xylene, melted and pressed at 250°C, and cooled and solidified.

This material could not be peeled off by hand.

Comparative Example 9 When the modified polypropylene composition used in Comparative Example 3 was subjected to the same experiment as in Example 8, it was easily peeled off by hand.

Example 9 The modified polypropylene composition used in Example 2 was
After heating and degassing in the same manner as above, it was sandwiched between two aluminum plates wiped with xylene, melted and pressed at 250°C, and cooled and solidified.

This material could not be peeled off by hand.

Comparative Example 10 When the modified polypropylene composition used in Comparative Example 3 was subjected to the same experiment as in Example 9, it was easily peeled off by hand.

Comparative Example 11 The modified polypropylene composition obtained in Comparative Example 3 was dissolved in xylene by boiling, and after cooling, it was precipitated with a large amount of acetone, filtered, and dried under reduced pressure at 50° C. for 24 hours.

MF I of this modified polypropylene composition vAA = 17
．． 9Y710 minutes, total maleic anhydride amount is 0.067 mol%, graft reaction maleic anhydride amount is 0.055 mol%
The amount of unreacted maleic anhydride was 0.012 mol%.

Next, modified polypropylene composition 'IMA) 100 parts by weight, BHTo, 1 part by weight, calcium stearate 0.1
The weight parts were mixed in a Henschel mixer for 5 minutes, L/D=
The saponified EVA obtained in the same manner as in Example 2 was pelletized at 220°C using a 40 mmφ extruder.
The adhesion strength with the material was 300S'/2cIrL.

Comparative Example 12 The modified polypropylene composition (A) obtained in Comparative Example 11 was extracted with acetone for 8 hours using a Soxhlet extractor, and
Dry under reduced pressure at ℃ for 24 hours to obtain MFI = 17.5? /
After 10 minutes, a modified polypropylene composition (1 mB) containing a total amount of maleic anhydride of 0.057 mol %, an amount of graft-reacted maleic anhydride of 0.054 mol %, and an amount of unreacted maleic anhydride of 0.003 mol %) was obtained.

Next, 100 parts by weight of modified polypropylene composition (B),
0.05 parts by weight of maleic anhydride, 1 part by weight of BHTo, and 0.1 parts by weight of calcium stearate were mixed in a Henschel mixer for 5 minutes, and a 40 m7 IL with L/D = 24 was mixed.
Pelletization was performed at 220°C using a φ extruder, and MF I
= 18.3 P710 minutes, total maleic anhydride amount 0.
068 mol%, graft reaction maleic anhydride amount 0.05
A modified polypropylene composition containing 5 mol% and an amount of unreacted maleic anhydride of 0.013 mol% was obtained.

This composition and saponification EV determined in the same manner as in Example 2
The adhesive strength with A was 100P/2cIIL.

Comparative Example 13 The same procedure as Comparative Example 12 was carried out except that maleic anhydride was not added.

The adhesive strength between the obtained modified polypropylene composition and saponified EVA was 1800f/2CrfL.

Table 2 below shows Example 2 and Comparative Examples 11, 12 and 13.
The results are also shown.

Claims (1)

[Scope of Claims] 1. 90 to 50 parts by weight of modified polypropylene obtained by melt-kneading a mixture of polypropylene, an unsaturated carboxylic acid or its derivative, and an organic peroxide, and 10 parts by weight of ethylene-α-olefin random copolymer. A method for producing a modified polypropylene composition, which comprises melting and pelletizing a mixture of 50 parts by weight and then heat-treating the mixture at a temperature of 60° C. or higher for 10 minutes to 10 hours. 2. The method according to claim 1, wherein the unsaturated carboxylic acid derivative is maleic anhydride. 3. The method according to claim 1, wherein the heating temperature is 100°C or higher and lower than the melting point of the modified polypropylene. 4. The method according to claim 1, wherein the modified polypropylene composition is heated and degassed so that the residual unreacted monomer in the modified polypropylene composition is 0.05 mol% or less. 5. The method according to claim 1, wherein the ethylene-α-olefin random copolymer is an ethylene-butene-1 random copolymer rubber or an ethylene-propylene random copolymer rubber. 6 A patent in which the modified polypropylene is obtained by melt-kneading a mixture consisting of 100 parts by weight of polypropylene, 0.05 to 5 parts by weight of an unsaturated carboxylic acid or its derivative, and 0.01 to 1 part by weight of an organic peroxide. The method according to claim 1.