JPH0341105B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Application Field] The present invention relates to a modified polyethylene composition with excellent adhesive properties and a multilayer laminate using the same. It is laminated with a hydrophilic thermoplastic resin film or sheet and used as a packaging film, and is also used as an adhesive in the form of powder, film, or sheet. [Prior Art] Multilayer laminates are known in which two or more resin films or sheets are laminated to take advantage of the strengths of each resin, and polyethylene can also be laminated with other resin films and formed into multilayer laminates. things are being done. There is also modified polyethylene whose adhesiveness has been improved by grafting unsaturated carboxylic acid or the like onto polyethylene. [Problem to be solved by the invention] Polyethylene film has poor adhesion to other resin films, so it is necessary to directly bond them to each other without using any other adhesive or the like to form a multilayer laminate that is difficult to peel off. It is impossible to obtain things. Further, since the above-mentioned modified polyethylene still has insufficient adhesive properties, a multilayer laminate having sufficient adhesive strength cannot be obtained even if this modified polyethylene is used. [Means for Solving the Problems] In view of the above-mentioned points, the present inventors conducted intensive studies to provide polyethylene with excellent adhesiveness to other resins, and as a result, grafted a specific unsaturated monomer. A modified polyethylene composition containing a specific ratio of modified high-pressure polyethylene and modified linear low-density polyethylene or modified high-pressure polyethylene grafted with a specific unsaturated carboxylic acid or its anhydride has extremely excellent adhesive properties. It has been found that a multilayer laminate with no risk of peeling can be obtained by laminating it with other resin films. The present invention was made based on the above findings, and
Modified linear low-density polyethylene prepared by grafting one or more α,β-unsaturated carboxylic acids or anhydrides to 100 parts by weight of modified high-pressure polyethylene grafted with one or more epoxy group-containing unsaturated monomers having one or more epoxy groups. The present invention provides a modified polyethylene composition containing 5 to 100 parts by weight of modified high-density polyethylene, and a multilayer laminate comprising a layer made of the modified polyethylene composition and a thermoplastic resin layer having hydrophilic properties. be. The modified polyethylene composition of the present invention and the multilayer laminate using the same will be explained in detail below. The modified high-pressure polyethylene, which is one of the ingredients of the modified polyethylene composition of the present invention, is produced by grafting one or more epoxy group-containing unsaturated monomers having one or more epoxy groups to high-pressure polyethylene. . As the epoxy group-containing unsaturated monomer,
Glycidyl methacrylate, glycidyl acrylate, vinyl glycidyl ether, allyl glycidyl ether, vinyl glycidyl thioether, p
-glycidylstyrene, etc., and glycidyl methacrylate is particularly preferred. The amount of the above epoxy group-containing unsaturated monomer to be grafted onto high-pressure polyethylene is 0.01×10 ^-4 ~
It is preferable to set the amount to 1.0×10 ⁻⁴ mole/g (relative to polyethylene). As a method for grafting the above-mentioned epoxy group-containing unsaturated monomer to high-pressure polyethylene, for example, a mixture of high-pressure polyethylene and an epoxy group-containing unsaturated monomer is extruded in the presence of a polymerization initiator such as t-butyl hydroperoxide. Examples include a method of melt-kneading using a machine or the like. In addition, modified linear low-density polyethylene or modified high-density polyethylene, which is another compounding component, is
It is produced by grafting one or more α,β-unsaturated carboxylic acids or anhydrides thereof onto linear low-density polyethylene or high-density polyethylene. The above-mentioned linear low-density polyethylene is produced by combining ethylene and α-olefin, such as butene, in the presence of a Ziegler-based or chromium-based catalyst at low or high pressure.
A copolymer with one selected from the group consisting of 1, pentene-1, hexene-1, 4-methylpentene-1, heptene-1, and octene-1, with a density of
It is 0.915 to 0.935 g/cm ³ . In addition, the above-mentioned high-density polyethylene refers to Phillips process polyethylene obtained by polymerizing ethylene using a catalyst such as chromium oxide supported on alumina or silica-alumina, or polymerized using a catalyst such as molybdenum oxide supported on alumina. Standard method polyethylene obtained by polymerization using a Ziegler type catalyst consisting of a transition metal compound and an organometallic compound, and having a density of 0.935 to 0.965.
g/ ^cm3 . The linear low density polyethylene to the high density polyethylene preferably has a melt index of 0.1 to 50 g/10 minutes and a melting point of 110 to 135°C. Examples of the α,β-unsaturated carboxylic acid or anhydride thereof include maleic acid, itaconic acid, citraconic acid, and anhydrides of these acids, with maleic anhydride being particularly preferred. The above α, β to be grafted onto the above polyethylene
- the amount of unsaturated carboxylic acid or its anhydride is 0.01
×10 ^-4 ~1.0×10 ^-4 mole/g (vs. polyethylene)
It is preferable to make it so that The above-mentioned α,β-unsaturated carboxylic acid or its anhydride can be grafted onto the above-mentioned polyethylene by a method similar to that used for grafting the epoxy group-containing unsaturated monomer onto the above-mentioned high-pressure polyethylene. In the present invention, the blending ratio of the modified high-pressure polyethylene and the modified linear low-density polyethylene to the modified high-density polyethylene is 5 to 100 parts by weight, preferably 10 parts by weight, to 100 parts by weight of the former.
~60 parts by weight. If the blending ratio is outside the above range, the adhesiveness will be insufficient. Furthermore, the modified polyethylene composition of the present invention includes:
It is possible to contain an elastomer or a modified elastomer in which one or more α,β-unsaturated carboxylic acids or anhydrides thereof are grafted onto the elastomer. Examples of the elastomer include ethylene-propylene copolymer rubber, butyl rubber, polyisobutylene, ethylene-butene-1 copolymer rubber, styrene-butadiene copolymer rubber, and the like. Further, as the α,β-unsaturated carboxylic acid or its anhydride used to obtain the above-mentioned modified elastomer, those exemplified as those used in the production of the above-mentioned modified linear low-density polyethylene or modified high-density polyethylene can be used. Similar methods can be mentioned, and the method of grafting α,β-unsaturated carboxylic acid or its anhydride to the elastomer is also the same as the method for producing modified linear low-density polyethylene or modified high-density polyethylene described above. Can be adopted. The amount of α,β-unsaturated carboxylic acid or its anhydride to be grafted to the elastomer is 0.01×10 ^-4 ~
It is preferable to set the amount to 1.0×10 ⁻⁴ mole/g (relative to elastomer). The content of the elastomer or the modified elastomer is 5 to 100 parts by weight of the blend of 100 parts by weight of the modified high-pressure polyethylene and 5 to 100 parts by weight of the modified linear low-density polyethylene or the modified high-density polyethylene. Preferably, the amount is 50 parts by weight. By containing the above-mentioned elastomer or the above-mentioned modified elastomer, the adhesiveness and low-temperature properties of the modified polyethylene composition of the present invention can be further improved, and the mechanical strength, transparency, gloss, etc. of the multilayer laminate can be improved. be able to. The above-mentioned modified polyethylene composition of the present invention can be molded by a method similar to that of ordinary polyethylene, such as extrusion molding, and can be molded into a film or sheet, and can be used alone or as a hydrophilic thermoplastic resin film. Or it can be laminated with a sheet and used as a packaging film, etc. It can also be used as a powder,
It is also used as an adhesive in the form of a film or sheet. A multilayer laminate obtained using the modified polyethylene composition of the present invention can be obtained by molding the modified polyethylene composition of the present invention and the hydrophilic thermoplastic resin into a film or sheet by extrusion or the like, respectively. , are manufactured by laminating them. Preferred examples of the hydrophilic thermoplastic resin include polyamides such as 6-nylon, 66-nylon, 11-nylon, 12-nylon, 6-66 copolymerized nylon, and saponified products of ethylene-vinyl acetate copolymer (saponified EVA). ) or partially saponified polyolefins. Lamination of the film or sheet of the modified polyethylene composition and the film or sheet of the thermoplastic resin can be carried out, for example, by overlapping a film of the modified polyethylene composition and a film of the thermoplastic resin and heating and pressurizing them; This can be carried out by a method in which a film of a modified polyethylene composition and a film of a thermoplastic resin are simultaneously extruded and bonded together. The following are production examples, examples of the present invention, and comparative examples of modified high-pressure polyethylene, modified linear low-density polyethylene, and modified high-density polyethylene, which are components of the modified polyethylene composition of the present invention. It will be explained in more detail. Production example 1 Melt index (MI) 2.0g/10 minutes, density
0.922g/ ^cm3 high-pressure polyethylene (manufactured by Ube Industries,
Glycidyl methacrylate 0.5 x 10 ^-4 mole/g (relative to polyethylene), t-butyl hydroperoxide 0.16 x
After dry blending 10 ^-4 mole/g (relative to polyethylene) with a ribbon blender, the screw diameter was adjusted to 240℃, screw diameter 65mmφ, L/
The mixture was melt-kneaded using a D22 extruder with a residence time of about 1 minute to obtain a modified high-pressure polyethylene (modified sample A) according to the present invention. Production example 2 Melt index (MI) 2.0g/10 minutes, density
0.922g/ ^cm3 high-pressure polyethylene (manufactured by Ube Industries,
Maleic anhydride 0.3×10 ^-4 mole/g (relative to polyethylene), t
-Butyl hydroperoxide 0.096×10 ^-4 mole/
g (for polyethylene) with a ribbon blender, and then melt-kneaded in the same manner as in Production Example 1.
A modified high-pressure polyethylene (modified sample B) was obtained. Production example 3 Melt index (MI) 15g/10 minutes, density
0.96g/ ^cm3 high-density polyethylene (manufactured by Nissan Chemical,
Low pressure high density polyethylene grade 1150 powder)
Glycidyl methacrylate 0.5×10 ^-4 mole/g
(based on polyethylene) and t-butyl hydroperoxide 0.16×10 ^-4 mole/g (based on polyethylene) were dry-blended using a ribbon blender, and then melt-kneaded in the same manner as in Production Example 1 to obtain modified high-density polyethylene (modified sample C). ) was obtained. Production example 4 Melt index (MI) 15g/10 minutes, density
0.96g/ ^cm3 high-density polyethylene (manufactured by Nissan Chemical,
Low pressure high density polyethylene grade 1150 powder)
Maleic anhydride 0.5×10 ^-4 mole/g (relative to polyethylene), t-butyl hydroperoxide 0.16×
After dry blending 10 ^-4 mole/g (based on polyethylene) using a ribbon blender, the mixture was melt-kneaded in the same manner as in Production Example 1 to obtain a modified high-density polyethylene (modified sample D) according to the present invention. Production example 5 Melt index (MI) 12g/10 minutes, density
0.926g/cm ³ , melting point 124℃ linear low-density polyethylene (manufactured by Ube Industries, linear low-density polyethylene
LLDPE) to maleic anhydride 0.5×10 ^-4 mole/g
(based on polyethylene) and t-butyl hydroperoxide 0.16×10 ^-4 mole/g (based on polyethylene) were dry-blended using a ribbon blender, and melt-kneaded in the same manner as in Production Example 1. Density polyethylene (modified sample E) was obtained. Production example 6 Melt index (MI) 5g/10 minutes, density
0.88g/ ^cm3 of ethylene-propylene copolymer rubber (manufactured by Mitsui Petrochemicals, ethylene-propylene copolymer rubber grade P0 180) with 0.5x maleic anhydride.
10 ^-4 mole/g (for copolymer rubber) and t-butyl hydroperoxide 0.16 x 10 ^-4 mole/g (for copolymer rubber) were dry-blended using a ribbon blender, and then melt-kneaded in the same manner as in Production Example 1. Thus, a modified ethylene-propylene copolymer rubber (modified sample F) was obtained. Production example 7 Melt index (MI) 2.0g/10 minutes, density
0.922g/ ^cm3 high-pressure polyethylene (manufactured by Ube Industries,
Glycidyl methacrylate 0.3 x 10 ^-4 mole/g (relative to polyethylene), t-butyl hydroperoxide 0.096 x
After dry blending 10 ^-4 mole/g (based on polyethylene) using a ribbon blender, the mixture was melt-kneaded in the same manner as in Production Example 1 to obtain a modified high-pressure polyethylene (modified sample G) according to the present invention. Production example 8 Melt index (MI) 15g/10 minutes, density
0.96g/ ^cm3 high-density polyethylene (manufactured by Nissan Chemical,
Low pressure high density polyethylene grade 1150 powder)
Glycidyl methacrylate 1.0×10 ^-4 mole/g
(based on polyethylene) and t-butyl hydroperoxide (based on polyethylene), ^0.32 ) was obtained. The melt index (MI), density, amount of maleic anhydride added or amount of glycidyl methacrylate added of modified samples A to H obtained in Production Examples 1 to 8 are summarized in Table 1 below.

【table】

[Table] Examples and Comparative Examples Modified polyethylene compositions were obtained using the formulations shown in Table 2 below. Adhesion tests were conducted on these modified polyethylene compositions using the test method shown below.
The results are summarized in Table 2 below. Test method (i) Adhesion to nylon sheet (peel strength) Nylon sheet (5033B, 50 x 100 x 0.5 mm)
and a sheet (50 x 100 x 0.5 mm) made from a modified polyethylene composition, placed in an oven kept at 210°C, and heated at a load of 20 g/cm ³ for 5 minutes.
After stacking by pressure bonding for a minute, samples were obtained by dropping them into water and rapidly cooling them. In addition, samples were obtained in the same manner when the oven temperature was changed to 230°C and 250°C and the layers were laminated. Cut 15mm from both ends of this sample and size it to 20×100.
After adjusting the size to 0.5 mm, the T-peel strength is measured using a tensile tester manufactured by Instron at a speed of 10 mm/min. (ii) Adhesion with saponified EVA sheet (peel strength) Adhesion with nylon sheet except when saponified EVA sheet (EVAL EP-F, 50 x 100 x 0.5 mm) is used instead of nylon sheet Measure the T-peel strength in the same manner as above. (iii) Multilayer laminate with nylon film and saponification
Adhesion (peel strength) of a multilayer laminate with an EVA film A multilayer laminate of a modified polyethylene composition film and a nylon film, and a modified polyethylene composition film were saponified using an extruder under the following molding conditions and extrusion temperature. A multilayer laminate with EVA film is prepared, and the peel strength is measured by the method described below. (a) Molding conditions BUR2, take-up speed 12m/min, folding diameter 240mm,
75mmφ double layer die, film thickness 40μ each

[Table] Products
Saponified EVA 190 200 200 220
(c) Method for measuring peel strength T-peel strength is measured at a speed of 50 mm/min using an Instron tensile tester in accordance with JIS K6854.

【table】

[Effects of the present invention]

Since the modified polyethylene composition of the present invention has excellent adhesiveness with other resins, it can be molded into a film or sheet and laminated with other resin films or sheets to form a multilayer laminate with no risk of peeling. It can also be used as an adhesive in the form of powder, film, or sheet.Furthermore, the film, sheet, etc. formed from the modified polyethylene composition of the present invention has good printability and dyeability. It has various excellent effects.

[Claims]

1 (1) 100 parts by weight of a curable epoxy resin, (2) A conjugated diolefin polymer with a number average molecular weight of 300 to 10,000 or a conjugated diolefin copolymer with a conjugated diolefin unit of 50 mol% or more, catalyzed with aluminum phenoxide. 30 to 300 parts by weight of a phenol-added conjugated diolefin polymer to which a phenol has been added as an essential component.