JPH0481486A - Bonding composition - Google Patents

Abstract

PURPOSE:To obtain the subject composition, containing a crystalline olefinic polymer modified with an unsaturated carboxylic acid (anhydride) and a thermoplastic polyester and capable of exhibiting excellent adhesive strength to nonpolar and polar substrates. CONSTITUTION:The objective composition containing (A) 100 pts.wt. crystalline olefinic polymer [preferably propylene (co)polymer having 100-200 deg.C melting point] modified with an unsaturated carboxylic acid (anhydride) (preferably maleic anhydride) and (B) 5-200 pts.wt. thermoplastic polyester.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to adhesive compositions. More specifically, the present invention relates to an adhesive composition that exhibits excellent adhesive strength to nonpolar and polar substrates.

(Prior art) Generally, base materials made of polyolefin, aluminum, polyester, steel, etc. are laminated together or laminated with porous materials such as paper, wood, synthetic resin foam, etc. to produce packaging materials, industrial materials, etc. It is used in many fields such as materials, automobile parts, construction materials, household goods, medical supplies, and sporting goods.

Adhesives are usually used when laminating these various products. The physical properties required of this adhesive are diverse and differ depending on the field of application, but the ones that are particularly required are nonpolar base materials such as polyolefin, aluminum, polyester, steel, etc. This is the adhesive strength with typical polar base materials, that is, the adhesive strength between different types of base materials.

Various proposals have been made to improve this adhesiveness.
One such method is a method of grafting a monomer consisting of an unsaturated carboxylic acid or its derivative to polypropylene (for example, Japanese Patent Publication No. 43-27421, Japanese Patent Publication No. 44-1).
5422), and a method of mixing ethylene-propylene random copolymer rubber with modified polypropylene grafted with an unsaturated carboxylic acid or a derivative thereof has been proposed (Japanese Patent Application Laid-open No. 80334/1983). Furthermore, a method has been proposed in which a mixture of a propylene-ethylene block copolymer, an ethylene-α-olefin random copolymer rubber, an unsaturated carboxylic acid or its derivative, and an organic peroxide is melt-kneaded (Japanese Patent Publication No. 61 -48526
issue). However, these adhesives could not be said to have sufficient adhesion to either nonpolar substrates or polar substrates.

(Problems to be Solved by the Invention) In view of the current situation, the present inventors have developed an adhesive composition that combines a nonpolar base material such as polyolefin with a polar base material such as aluminum, polyester, and steel. As a result of various studies in order to develop a product with satisfactory adhesive strength, we found a product made by mixing a specific olefin polymer modified by grafting with an unsaturated carboxylic acid and a thermoplastic polyester in a predetermined ratio. It was discovered that the present invention can be adapted to the purpose, and based on this knowledge, the present invention was accomplished.

(Means for Solving the Problems) That is, the present invention provides that (B) 5 to 20 parts by weight of a thermoplastic polyester to 100 parts by weight of a crystalline olefin polymer modified with an unsaturated carboxylic acid or its acid anhydride.
The present invention provides an adhesive composition characterized in that it contains 0 parts by weight.

In the present invention, examples of the crystalline olefin polymer as component (A) include propylene homopolymer, copolymer of propylene and other olefins, low density polyethylene, high density polyethylene, and polybutene-1. These crystalline olefin polymers preferably have a melting point of about 100 to 200°C. In particular, propylene homopolymers and copolymers of propylene and other olefins are preferably used.

Examples of the unsaturated carboxylic acid or its acid anhydride in component (A) include acrylic acid, methacrylic acid, maleic acid, fumaric acid, itaconic acid, crotonic acid, citraconic acid, maleic anhydride, itaconic anhydride, and citraconic anhydride. etc. can be mentioned. Among these, it is most preferred to use maleic anhydride. These unsaturated carboxylic acids or other acid anhydrides can be mixed with the crystalline olefin polymer in the presence of an organic peroxide by heating in a solution, slurry or melt state using a conventional method. Graft polymerized onto the polymer component. The unsaturated carboxylic acid or its acid anhydride is preferably used in an amount of 0.01 to 5 parts by weight per 100 parts by weight of the crystalline olefin polymer.

The thermoplastic polyester in component (B) has plasticity in a high temperature range and can be molded into any shape, has an ester bond in the main chain of the polymer, and is usually a dibasic acid or a dibasic polyester. Obtained by copolymerizing alcohol. If necessary, trivalent or higher acid and glycol are also copolymerized. It can also be obtained by ring-opening polymerization of ε-caprolactone and the like. Examples of the bicyclic acid include terephthalic acid, isophthalic acid, phthalic anhydride, succinic acid, adipic acid, azelaic acid, sebacic acid, dodecanedioic acid, dimer acid, paraoxybenzoic acid, trimellitic anhydride, and the like. Examples of dihydric alcohols and trihydric or higher glycols include ethylene glycol, propylene glycol, 1,4-butanediol, 1,5-bentanediol, 1,6-hexanediol, neopentyl glycol, polyethylene glycol, polypropylene glycol, Examples include polytetramethylene glycol, 1,4-cyclohexane dimetatool, pentaerythritol, polybutadiene diol, hydrogenated polybutadiene diol, and the like.

If the amount of component (B) is less than 5 parts by weight relative to 100 parts by weight of component (A), the adhesive force with the polar substrate will be insufficient;
If the amount of component (B) exceeds 200 parts by weight, the adhesive strength to the nonpolar substrate will be insufficient.

Further, other polymers than those mentioned above can be used in the adhesive composition of the present invention within a range that does not impair the properties required therein.

Examples of such polymers include amorphous olefin polymers such as ethylene-propylene rubber and ethylene-propylene-diene rubber, ethylene-vinyl ester copolymers, styrene-olefin block copolymers, and polyamides.

The adhesive composition is prepared by melting each of the above components using a Banbury mixer, a kneader 1 extruder, etc. at a temperature that is higher than the melting point of both components (A) and (B) and higher than the decomposition temperature of component (D). After kneading, it is formed into granules, flakes, pellets, rods, etc., and used for adhesion tests.

The adhesive composition of the present invention containing both components (A) and (B) above as basic essential components may optionally contain a tackifier resin, wax, plasticizer, filler, antioxidant, solvent, etc. can be blended to prepare a hot melt adhesive.

Examples of tackifying resins include rosin or its derivatives, terpene resins, terpene-phenol resins, aromatic, aliphatic, alicyclic or copolymerized petroleum resins, coumaron-indene resins, and phenolic resins. , styrene resin, etc.

Examples of the wax include paraffin wax, microcrystalline wax, polyethylene wax, and polypropylene wax.

The adhesive composition of the present invention thus prepared can be used as an effective adhesive for non-polar substrates such as polyolefins and polar substrates such as aluminum, polyester, steel, etc. I can do it.

The adhesive composition can be applied to these substrates, for example, by the following method.

(1) A method in which a film or sheet of an adhesive composition formed by heat-adhesive inflation method, T-Guy method, etc. is sandwiched between base materials and heat-sealed.

Alternatively, a method in which an adhesive composition is laminated in advance on one base material side by a coextrusion method, an extrusion coating method, etc., and then the other base material is laminated.

(2) Through a molten film of adhesive composition by sandwich lamination method T-Guy method, etc.
How to bond base materials together.

(3) Coextrusion method If the base material can be extruded, including the adhesive composition,
A method in which all constituent layers are coextruded and laminated using an extrusion molding method.

(4) Hot-melt method An adhesive composition to which tackifying resin, wax, etc. are added as necessary is applied to the base material using a hot-melt gun, roll coater-1 extrusion coater, etc., and bonded by pressure. Method.

(Effects of the Invention) The adhesive composition according to the present invention exhibits excellent adhesion to nonpolar substrates such as polyolefin and polar substrates such as aluminum, polyester, steel, etc.
It can be effectively used in many fields such as packaging materials, industrial materials, automobile parts, building parts, household goods, medical goods, and sporting goods.

(Examples) Next, the present invention will be described in more detail based on examples. The performance test results for each example are shown in Table 1 below.

Note that performance tests of the compositions prepared in each Example and Comparative Example were conducted as follows.

(Adhesive Strength) The adhesive composition was heated and melted at 180° C., and a sheet with a thickness of 0.1 mm was created using a hot press.

This adhesive sheet was sandwiched between base materials, and it was heat-sealed using a heat sealer at a sealing temperature of 160°C and a sealing time of 3 seconds.Then, the sample was cut into a width of 25 mm. using a tensile speed of 200
T-peel strength was measured under conditions of mm/min and measurement temperature of 20°C.

The base materials for measuring adhesive strength were a polypropylene film (PP, thickness 0.3 mm) and an aluminum plate (Al1
, 0.1 mm thick) were used, respectively.

(Melt viscosity) Melt viscosity at 180°C was measured using a B-type rotational viscometer.

Reference Example 1 (A) Maleic anhydride-modified propylene polymer-1 (MA
H-modified PP-1) Propylene homopolymer (MI40. Melting point 160°C)
100 parts by weight of maleic anhydride, 1 part by weight of maleic anhydride, and 0.5 parts by weight of dicumyl peroxide as an organic peroxide were mixed in a Henschel Mikie under a nitrogen atmosphere, and this mixture was extruded using an extruder at a resin temperature of 220°C. It was made into pellets.

The grafting rate of maleic anhydride in this product was 95%.

Reference Example 2 (B) Maleic anhydride modified propylene polymer-2 (MA
H-modified PP-2) Propylene copolymer (ethylene content 5% by weight, MI
20, melting point 150°C) 100 parts by weight, maleic anhydride 0
．． 5 parts by weight, α,α′-bis(t-
Butylperoxy-m-isopropyl)benzene 0.2
Mix the weight parts in a hexyl hemiscer under a nitrogen atmosphere,
This mixture was extruded using an extruder at a resin temperature of 220°C to form pellets. The grafting rate of maleic anhydride in this product was 92%.

Example 1 UE-3210 (trade name, manufactured by Unitika Co., Ltd.) 20 was added as a thermoplastic polyester to 100 parts by weight of maleic anhydride-modified propylene polymer-1 prepared according to Reference Example 1.
Parts by weight were blended using a Henschel mixer, and this mixture was extruded using an extruder at a resin temperature of 200°C to form pellets.

The adhesive strength and melt viscosity of the adhesive composition thus prepared were measured.

Example 2 100 parts by weight of maleic anhydride-modified propylene polymer-2 prepared according to Reference Example 2 was used as thermoplastic polyester Vyron GM900 (trade name, manufactured by Toyobo Co., Ltd.)
50 parts by weight were blended using a Henschel mixer, and this mixture was extruded using an extruder at a resin temperature of 200°C to form pellets.

The adhesive strength and melt viscosity of the adhesive composition thus prepared were measured.

Example 3 50 parts by weight of the maleic anhydride-modified propylene polymer-1 prepared in Reference Example 1 and an unmodified propylene copolymer (abbreviated as unmodified PP-2) were prepared.

(Ethylene content 5% by weight, MI 20, melting point 150°C)
AHM as thermoplastic polyester for 50 parts by weight
150 parts by weight of -400 (trade name, manufactured by Asahi Kasei Corporation) were blended using a Henschel mixer, and this mixture was extruded using an extractor at a resin temperature of 200°C to form pellets.

The adhesive strength and melt viscosity of the adhesive composition thus prepared were measured.

Example 4 Maleic anhydride-modified propylene polymer-2 prepared according to Reference Example 2 was thermoplastic based on 70 parts by weight and 30 parts by weight of unmodified propylene homopolymer (abbreviated as PP-1, MI40, melting point 160°C). VPE-47 as polyester
40 parts by weight of 09A (trade name, manufactured by Gutdeyer) were blended using a Henschel mixer, and this mixture was extruded using an extruder at a resin temperature of 200° C. to form pellets.

The adhesive strength and melt viscosity of the adhesive composition thus prepared were measured.

Comparative Example 1 The adhesive strength and melt viscosity of maleic anhydride-modified propylene polymer-1 prepared in Reference Example 1 were measured.

Comparative Example 2 100 parts by weight of the maleic anhydride-modified propylene polymer-1 prepared in Reference Example 1 was blended with 2 parts by weight of UE-3210 (trade name, manufactured by Unitika) as a thermoplastic polyester using a Henschel mixer. This mixture was extruded using an extruder at a resin temperature of 200°C to form pellets.

The adhesive strength and melt viscosity of the adhesive composition thus prepared were measured.

Comparative Example 3 50 parts by weight of maleic anhydride-modified propylene polymer-1 prepared according to Reference Example 1 and an unmodified propylene copolymer (abbreviated as unmodified PP-2, ethylene content 5% by weight)
, MI 20, melting point 150°C) and 150 parts by weight of Vylon GM900 (trade name, manufactured by Toyobo Co., Ltd.) and 150 parts by weight of AHM-400 (trade name, manufactured by Asahi Kasei Co., Ltd.) as thermoplastic polyesters were mixed in a Henschel mixer. Blend this mixture using an extruder at a resin temperature of 2.
It was extruded at 00°C to form a pellet.

The adhesive strength and melt viscosity of the adhesive composition thus prepared were measured.

The results in Table 1 show that the adhesive of the comparative example has poor adhesion to either the polypropylene film or aluminum plate, whereas the adhesive of the example of the present invention has poor adhesion to either of the above substrates. It can be seen that the adhesive exhibits excellent adhesion.

Claims (1)

[Claims] 1. Contains 5 to 200 parts by weight of (B) thermoplastic polyester based on 100 parts by weight of (A) crystalline olefin polymer modified with unsaturated carboxylic acid or its acid anhydride. An adhesive composition characterized by: 2. The adhesive composition according to claim 1, wherein the crystalline olefin polymer in component (A) is a propylene homopolymer or copolymer. 3. The adhesive composition according to claim 1 or 2, wherein the unsaturated carboxylic acid or its acid anhydride in component (A) is maleic anhydride.