JPH0948098A - Polypropylene-base resin laminate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To increase the adhesion strength of a polypropylene-base resin laminate. SOLUTION: A laminate is formed of (A) a polypropylene-base resin and (B) a polyolefin-base resin. At least one of the resin components contains at least 1wt.% but at most 5wt.% of an ethylene-α-olefin co-polymer elastomer that meets the following conditions: the content of α-olefin having carbon atoms of 4 to 20 is greater than 65wt.% but less than 95wt.%; the density at 23 deg.C is less than 0.88G/cm<3> ; and no crystal melting peak is observed by a differential scanning calorimeter.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a polypropylene resin laminate, and more particularly to a polypropylene resin / polyolefin resin laminate having excellent adhesive strength.

[0002]

2. Description of the Related Art Polypropylene resin (hereinafter referred to as "PP") is often used by being laminated with the same or different polyolefin resin for the purpose of improving physical properties. Often poor and often problematic. To avoid this problem, adhesive resin is often added, but addition of adhesive resin often impairs transparency, and contamination of the molding machine due to metal adhesion of adhesive resin is avoided. There were many problems such as not having it. Further, although the addition of an elastomer component represented by ethylene / propylene rubber slightly improves the adhesiveness, it significantly impairs the transparency and greatly changes the appearance, so that its use is limited. Furthermore, an increase in the bonding temperature not only causes an increase in energy cost, but also causes deterioration of the resin and yellowing, which is not preferred.

As described above, although there has been a strong demand for improving the adhesive strength of the polypropylene resin laminate, it has not been able to meet the needs of the market, which has been a serious problem.

[0004]

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and provides a polypropylene resin laminate showing excellent adhesiveness.

[0005]

Means for Solving the Problems The inventors of the present invention have conducted extensive studies to achieve the above object, and as a result, completed the present invention. That is, the present invention is a laminate comprising a polypropylene-based resin (A) and a polyolefin-based resin (B), wherein at least one of the resin components (a)-
The present invention relates to a polypropylene-based resin laminate, characterized by containing 1% by weight or more and 50% by weight or less of an ethylene / α-olefin copolymer elastomer (C) satisfying the condition (d).

(A) Carbon number of α-olefin: 4 or more and 20 or less (b) Content of α-olefin: greater than 65% by weight 9
5% by weight or less (c) Density at 23 ° C .: less than 0.88 g / cm ³ (d) Crystal melting peak by differential scanning calorimeter: not observed Below, the details will be described.

As the polypropylene resin (A) used in the present invention, a generally used crystalline polypropylene resin can be used. For example, polypropylene homopolymer, propylene / ethylene random copolymer having an ethylene content of 0.5 to 12% by weight, ethylene content of 0.5 to 12% by weight, and α-olefin content such as 1-butene of 0.5. ~ 20 wt% propylene / ethylene / α-olefin terpolymer, ethylene content 1
-60% by weight of impact PP (sometimes referred to as block PP), a crystalline polypropylene resin having a syndiotactic structure, and the like. Among these, one kind alone or a mixture of two or more kinds is used. To be

The melt flow rate of the polypropylene resin (A) is not particularly limited, but is 230 ° C., 2.16.
Under a kg load, those having a weight of 0.01 to 100 g / 10 minutes are preferably used.

Examples of the polyolefin resin (B) used in the present invention include polyethylene resins represented by high-density polyethylene, linear low-density polyethylene, branched low-density polyethylene, and ethylene-vinyl acetate copolymer resins. , Ethylene / ethyl acrylate copolymer resin, poly (1-butene), poly (4-methyl-1-pentene), thermoplastic polyolefin-based elastomer, polypropylene-based resin, and the like. One of these alone or It is used as a mixture of two or more kinds. When a polypropylene resin is used as the polyolefin resin (B), it is desired that the polypropylene resin (A), which is the other component of the present invention, be different in composition, molecular weight and the like, but they are the same raw material. However, if there are differences in the molecular orientation, crystallinity, etc., it is expected to improve the mechanical properties and the like by forming multiple layers. Therefore, it is preferably used like other polyolefin resins.

In the laminate of the present invention, 1% by weight or more and 50% by weight or less of the ethylene / α-olefin copolymer elastomer (C) is added to at least one of the polypropylene resin (A) and the polyolefin resin (B). After that, it is characterized by being molded. If it is less than 1% by weight, the adhesive strength of the obtained laminate may be poor, and if it exceeds 50% by weight, the flexibility of the obtained laminate may be deteriorated. In addition, it is preferably used in an amount of 3% by weight or more and 30% by weight or less from the viewpoint of improvement in adhesive strength and a balance between low temperature heat sealability and heat resistance.

The ethylene α- used in the present invention
The α-olefin of the olefin copolymer elastomer (C) has 4 to 20 carbon atoms, and for example, 1-
Butene, 1-pentene, 1-hexene, 4-methyl-1
-Pentene, 1-heptene, 1-octene, 1-nonene, 1-decene, 1-undecene, 1-dodecene, 1-
Tridecene, 1-tetradecene, 1-pentadecene, 1
-Hexadecene, 1-heptadecene, 1-octadecene, 1-nonadecene, 1-eicosene and the like, and one or more of these are used. Among them, 1-butene, 1-heptene, 1-hexene, 1-octene and the like are preferable from the viewpoint of availability.

The ethylene α- used in the present invention
The α-olefin content of the olefin copolymer elastomer (C) needs to be more than 65% by weight and 95% by weight or less, and within this range, a polypropylene resin laminate having excellent adhesive strength can be obtained.

Ethylene / α-used in the present invention
The density of the olefin copolymer elastomer (C) at 23 ° C. is less than 0.88 g / cm ³ . 0.8
When the ethylene / α-olefin copolymer has a content of 8 g / cm ³ or more, the adhesive strength of the obtained laminate may decrease.

Ethylene.alpha.-used in the present invention
The olefin copolymer elastomer (C) is characterized in that no crystal melting peak is observed by a differential scanning calorimeter (abbreviated as DSC). When an ethylene / α-olefin copolymer showing a crystal melting peak is used, the adhesive strength of the obtained laminate may decrease.

The ethylene α- used in the present invention
The molecular weight of the olefin copolymer elastomer (C) is not particularly limited, but the number average molecular weight measured by gel permeation chromatography (GPC) is preferably 5,000 to 1,000,000 in terms of polyethylene. If the number average molecular weight is less than 5,000, the resin tends to be sticky, and if it exceeds 1,000,000, molding may be difficult. In addition, in terms of easy handling and excellent moldability, it is 10,000 to 600
Those of 000 are particularly preferable.

Ethylene / α-used in the present invention
The molecular weight distribution (Mw / Mn) of the olefin copolymer elastomer (C) is not particularly limited, but is preferably 3 or less, and the high molecular weight fraction is 10% as an index of the composition distribution.
The ratio of the average α-olefin content (mol%) in the low-molecular-weight fraction 10% to the average α-olefin content (mol%) is preferably 1.2 or less, more preferably 1.15.
It is the following.

The method for producing the ethylene / α-olefin copolymer elastomer (C) described above is not particularly limited,
It can be produced using various catalysts such as a titanium-based catalyst, a vanadium-based catalyst, or a metallocene-based catalyst. Among them, it is preferable to use a metallocene-based catalyst that is easy to obtain an ethylene / α-olefin copolymer elastomer satisfying the above-mentioned molecular weight, molecular weight distribution and composition distribution.

That is, a catalyst composed of (a) a transition metal compound containing a transition metal of Group 4 of the periodic table, (b) a compound which reacts with this to form an ionic complex, and / or (c) an organometallic compound The ethylene / α-olefin copolymer elastomer can be produced by copolymerizing ethylene and the α-olefin in the presence of

Polymerization can be carried out by any of batch method, semi-continuous method and continuous method, and it is also possible to carry out in two or more stages by changing the polymerization conditions. The copolymer obtained after the completion of the polymerization is separated and recovered from the polymerization solution by a conventionally known method, and dried to obtain a solid copolymer.

The polypropylene resin (A) and the polyolefin resin (B) constituting the laminate of the present invention include organic and inorganic pigments, a crystal nucleating agent, a clarifying agent, an antiblocking agent, and a mold release agent. Agents, antistatic agents, slip agents, anti-fog agents, lubricants, heat stabilizers, UV stabilizers, weather resistance stabilizers, foaming agents, antifungal agents, rust preventives, ion trap agents,
A flame retardant, a flame retardant aid, and the like may be added as necessary.

It is also possible to add an adhesive resin to the laminate of the present invention. As the adhesive resin, polyolefin-based polyol, acid-modified polyolefin-based resin, ethylene / vinyl alcohol copolymer, saponified ethylene /
Examples thereof include vinyl acetate copolymer and polyvinyl alcohol.

The method for producing the laminate of the present invention is arbitrary,
(1) A method of adhering a polypropylene resin (A) and a polyolefin resin (B) by co-extrusion, such as multilayer molding such as a multilayer film, a multilayer sheet, and a multilayer blow, (2) one of the components in advance After molding, a method of adhering the other resin component by melt-coating on the surface thereof, (3) a method of preliminarily molding both components and then heat-sealing and adhering them, and the like are used.

Further, even if the laminate of the present invention is a laminate of three or more layers, it is sufficient that at least one set of two adjacent layers satisfies the constituent requirements of the present invention. Further, the laminate of the present invention may be uniaxially stretched or biaxially stretched if necessary.

[0024]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to examples, but these are only illustrative and not restrictive. Various measurements and ethylene and α in the examples
The olefin copolymer elastomer was synthesized by the following method.

(Α of ethylene / α-olefin copolymer
-Measurement of olefin content) It was calculated by measurement of ¹³ C-NMR spectrum (JNM GX400, manufactured by JEOL Ltd.) at 100 MHz in o-dichlorobenzene as a solvent.

(Measurement of Molecular Weight and Molecular Weight Distribution) o-
Gel permeation chromatography (manufactured by Millipore Corporation) at 140 ° C using dichlorobenzene.
It was calculated in terms of polyethylene by using 150C type GPC).

Synthesis Example 1 of ethylene / α-olefin copolymer elastomer To a 5 l autoclave were added 1000 ml of toluene and 500 ml of 1-butene, and the temperature was raised to 40 ° C. Furthermore, ethylene was introduced so that the total pressure would be 8 kg / cm ² . Next, 10 ml of toluene, 5 mmol of methylaluminoxane, and 5 μmol of titanium (dimethyl (t-butylamide) (tetramethyl-η5-cyclopentadienyl) silane) dichloride were added to another reaction vessel,
After stirring this mixed solution for 20 minutes, it was introduced into an autoclave and polymerization was started. This polymerization has a total pressure of 8 kg /
cm ² , ethylene was continuously introduced at 40 ° C.
For 30 minutes.

After the completion of the polymerization, the polymer was washed with a large amount of ethanol and dried under reduced pressure at 60 ° C. for 12 hours. As a result, ethylene 1- having a 1-butene content of 72% by weight was used.
44 g of a butene copolymer elastomer was obtained. Number average molecular weight 108,000, Mw / Mn = 2.2, density 0.86
It was 4 g / cm ³ .

Example 1 Propylene homopolymer (Tosoh Polypro J5100A
MFR: 10 g / 10 min, 230 ° C., 2.16 kg load) 144 g, and 36 g of ethylene / 1-butene copolymer elastomer obtained in Synthesis Example 1 were used using a Labo Plastomill (internal volume 200 cc, manufactured by Toyo Seiki Seisakusho). 60 rpm
Melt blended at 200 ° C. for 5 minutes. Then, the obtained composition was molded into a film having a thickness of 0.1 mm by a press molding machine set at 200 ° C. to obtain Sample A. Separately from this, linear low density polyethylene (Nipolon-LF
20-R Tosoh MFR: 2g / 10 minutes, 190
C., 2.16 kg load) was molded into a film having a thickness of 0.1 mm with a press molding machine set to 200.degree. Sample A and sample B are overlaid and heat-sealed 17
It was heat-sealed at 0 ° C. and 2 kg / cm ² for 1 second. This was cut into a width of 15 mm to obtain a test piece for measuring adhesive strength.

Synthesis Example 2 of Ethylene / α-Olefin Copolymer Elastomer 400 ml of toluene and 1 ml of 5 l of autoclave.
1100 ml of butene was added and the temperature was raised to 40 ° C. Furthermore, ethylene was introduced so that the total pressure would be 8 kg / cm ² . Next, 10 ml of toluene, 3 mmol of methylaluminoxane, and 3 μmol of diphenylmethylene (cyclopentadienyl-1-fluorenyl) zirconium dichloride were added to another reaction vessel, and this mixed solution was added to 20 ml.
After stirring for a minute, the mixture was introduced into an autoclave to start polymerization. This polymerization was carried out at 40 ° C. for 60 minutes by continuously introducing ethylene so as to keep the total pressure at 8 kg / cm ² .

After the completion of the polymerization, the polymer was washed with a large amount of ethanol and dried under reduced pressure at 60 ° C. for 12 hours. As a result, the ethylene 1-butene content of 77% by weight 1-
102 g of butene copolymer elastomer was obtained. Number average molecular weight 45,000, Mw / Mn = 2.6, density 0.86
It was ³ g / cm ³ .

Various ethylene / 1-butene copolymer elastomers were obtained by changing the amount of 1-butene and performing the same operation as above. Further, 1-butene was changed to 1-hexene and propylene to obtain various ethylene / α-olefin copolymer elastomers. The copolymers used are summarized in Table 1.

Example 2 Instead of the ethylene / 1-butene copolymer elastomer used in Example 1, ethylene / 1-obtained in Synthesis Example 2 was used.
Using butene copolymer elastomer, a test piece was obtained in the same manner as in Example 1.

Example 3 Instead of the ethylene / 1-butene copolymer elastomer used in Example 1, the 1-hexene content was 77% by weight.
A test piece was obtained in the same manner as in Example 1 by using the ethylene / 1-hexene copolymer elastomer.

Example 4 Instead of propylene homopolymer, ethylene / propylene random copolymer (Tosoh Polypro J6080A ethylene: 3.2 wt% MFR: 8 g / 10 minutes, 230
C., 2.16 kg load) was used, and a test piece was obtained in the same manner as in Example 1 except that the bonding temperature was 160.degree.

Example 5 Instead of linear low density polyethylene, branched low density polyethylene (PETROSEN 205 manufactured by Tosoh MFR: 3 g)
A test piece was obtained in the same manner as in Example 1 except that / 10 minutes, 190 ° C., 2.16 kg load) was used.

Example 6 Instead of linear low density polyethylene, high density polyethylene (Nipolon Hard 8300A manufactured by Tosoh MFR:
A test piece was obtained in the same manner as in Example 1 except that 0.35 g / 10 minutes, 190 ° C., 2.16 kg load) was used.

Example 7 Instead of linear low density polyethylene, an ethylene / propylene random copolymer (Tosoh Polypro J6080A) was used.
Ethylene: 3.2 wt% MFR: 8 g / 10 minutes, 23
0 ℃, 2.16kg load), and the adhesion temperature is 155 ℃
A test piece was obtained in the same manner as in Example 1 except for the above.

Example 8 Linear low density polyethylene (Nipolon-LF20-R
Tosoh MFR: 2g / 10 minutes, 190 ° C, 2.1
6 kg load) 144 g, ethylene-1 obtained in Synthesis Example 1-
36 g of butene copolymer elastomer was used with a Labo Plastomill (internal volume 200 cc, manufactured by Toyo Seiki Seisakusho) 6
Melt blended at 0 rpm for 5 minutes at 200 ° C. Then, the obtained composition was molded into a film having a thickness of 0.1 mm by a press molding machine set at 200 ° C. to obtain Sample A.

Separately from this, propylene homopolymer (Tosoh Polypro J5100A MFR: 10 g / 10 min,
Sample B was formed into a film having a thickness of 0.1 mm by a press molding machine set to 200 ° C. (230 ° C., 2.16 kg load).

Thereafter, adhesion was performed in the same manner as in Example 1 to obtain a test piece.

Example 9 A test piece was obtained in the same manner as in Example 1 except that 162 g of propylene homopolymer and 18 g of ethylene / 1-butene copolymer elastomer were used.

Comparative Example 1 A test piece was obtained in the same manner as in Example 1 except that the ethylene / 1-butene copolymer elastomer was not added.

Comparative Example 2 The same procedure as in Example 1 was repeated except that the ethylene / 1-butene copolymer elastomer used in Example 1 was replaced with an ethylene / 1-butene copolymer elastomer having a 1-butene content of 53% by weight. A test piece was obtained by the method.

Comparative Example 3 An ethylene / propylene copolymer elastomer having a propylene content of 75% by weight was used in place of the ethylene / 1-butene copolymer elastomer used in Example 1, and a test was conducted in the same manner as in Example 1. Got a piece.

Comparative Example 4 A test piece was obtained in the same manner as in Example 4 except that the ethylene / 1-butene copolymer elastomer was not added.

Comparative Example 5 A test piece was obtained in the same manner as in Example 5 except that the ethylene / 1-butene copolymer elastomer was not added.

Comparative Example 6 A test piece was obtained in the same manner as in Example 6 except that the ethylene / 1-butene copolymer elastomer was not added.

Comparative Example 7 A test piece was obtained in the same manner as in Example 7 except that the ethylene / 1-butene copolymer elastomer was not added.

The test pieces obtained above were evaluated by the following methods. The results are shown in Table 1.

(Measurement of Adhesive Strength) A T-type peel test was carried out using a Shopper tensile strength tester. Pulling speed is 300mm /
Minutes

[0052]

[Table 1]

[0053]

As described above, the polypropylene resin laminate of the present invention exhibits excellent adhesive strength.

Claims (1)

[Claims] 1. A laminate comprising a polypropylene resin (A) and a polyolefin resin (B), wherein at least one of the resin components is an ethylene / α-olefin satisfying the conditions (a) to (d). A polypropylene-based resin laminate, characterized by containing 1% by weight or more and 50% by weight or less of a copolymer elastomer (C). (A) α-olefin carbon number: 4 or more and 20 or less (b) α-olefin content: greater than 65% by weight and 9
5% by weight or less (c) Density at 23 ° C .: less than 0.88 g / cm ³ (d) Crystal melting peak by differential scanning calorimeter: not observed