JPS59164317A - Adhesive resin and its laminate - Google Patents

Abstract

PURPOSE:An adhesive resin excellent in adhesion to PVC resins and suitable in the production of laminates, obtained by grafting a specified polyolefin resin composition with an unsaturated carboxylic acid (anhydride) in the presence of a radical generator. CONSTITUTION:A resin composition is prepared by mixing 1-99wt% ethylene/ vinyl acetate copolymer of a vinyl acetate content of 3-50wt% with 99-1wt% ethylene/(meth)acrylate ester copolymer of a (meth)acrylate ester content of 1- 30wt%. 1-99pts.wt. this resin composition is further mixed with 99-1pt.wt. ethylene/alpha-olefin elastomer. 100pts.wt. resulting resin composition is grafted with an unsaturated carboxylic acid (anhydride) (e.g., acrylic acid or maleic anhydride) in the presence of 0.001-0.5pts.wt. radical generator to obtain the purpose adhesive resin.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides vinyl chloride resins, vinylidene chloride resins, polyamide resins, ethylene vinyl alcohol copolymers,
This invention relates to a graft-modified resin that has excellent adhesion to polyester resins, etc., and a laminate using the same. The present invention relates to a graft-modified resin and a laminate using the same.

Vinyl chloride resin, vinylidene chloride resin, polyamide resin, ethylene vinyl alcohol copolymer Q, polyester thread resin, etc. have excellent gas barrier properties and good oil resistance, chemical resistance, etc., so they are used in various applications. It is suitable as a packaging material, especially a food packaging material.

However, these resins generally have poor sealing properties, so they are often used by laminating them with resins that have good sealing properties, such as polyolefin resins, and this laminate is an excellent packaging product that combines the features of both. It becomes a kidnapping fee. However, although various acid-graft modified polyolefins have already been proposed and are actually used in the market as adhesives for these resins, their adhesion with vinyl chloride resins and vinylidene chloride resins is particularly poor. However, there is a strong demand for a resin with even stronger adhesive properties.

When vinyl chloride resin or vinylidene chloride thread resin is used as a packaging material, an appropriate amount of plasticizer is usually added to these resins to give the film flexibility and other properties (J). Thermal adhesion between mixed so-called soft vinyl chloride resin and polyolefin resin is particularly difficult, and this tendency increases as the amount of plasticizer increases, that is, as the resin becomes softer. This is thought to be because the plasticizer bleeds out and the adhesion with the polyolefin is inhibited by this plasticizer.And of course, if the adhesion is insufficient, it not only has a negative effect on oil resistance and heat resistance, but also has a negative effect on the seal. This greatly affects the strength, resulting in insufficient sealing and making it unusable.

Therefore, the present inventor has conducted extensive studies on adhesive resins that can be strongly thermally bonded to vinyl chloride thread resins or vinylidene chloride resins, and laminates that have excellent barrier properties, oil resistance, and sealing properties, beyond the adhesion inhibition caused by plasticizers. As a result, the present invention was arrived at, and the gist of the present invention is that vinyl acetate content of 3 to 50
wt% ethylene-vinyl acetate copolymer 1-99 wt%
and ethylene-acrylic ester #polymer or ethylene-methacrylic ester copolymer 99 with an acrylic ester or methacrylic ester content of 1 to 30 wt%
1 to 99 parts by weight of a resin composition consisting of ~1% by weight of a resin composition consisting of 99 to 1 part by weight of etrene-alpha olefin yarn elas).0001 to 05 parts by weight of a radical generator. An adhesive resin obtained by graft-modifying an unsaturated carboxylic acid or its anhydride in the presence of 1 to 99% by weight of an ethylene-vinyl acetate copolymer with a vinyl acetate content of 3 to 50% by weight, and an acrylic ester or methacrylic acid ester. , j IJ acid ester content] ~ 30 wt% of a resin composition consisting of 99 to 1 wt% of an ethylene-acrylic ester copolymer or an ethylene-methacrylic ester copolymer, and ethylene-α Resin composition 1.0 consisting of 99 to 1 part by weight of olefin elastomer
Adhesive resin layer and vinyl chloride resin layer or vinylidene chloride resin layer obtained by graft-modifying unsaturated carboxylic acid or its anhydride in the presence of 0.001 to 0.05 parts by weight of a radical generator based on 0 parts by weight. It is a laminate consisting of layers.

As the resin used for graft modification in the present invention, ethylene-vinyl acetate copolymer (hereinafter abbreviated as EVA) is
Vinyl acetate content (hereinafter abbreviated as vinyl acetate content) is 3 to 50
wt% is preferably 10 to 35 wt%, and the melt flow rate (according to JIS K6760, the same shall apply hereinafter) is not particularly limited, but is 0.5 to 300 g710
mm, preferably 1 to 30.9/IQmm, and 1 to 99% by weight, preferably 30 to 90% by weight in the resin composition
Use.

If the vinyl acetate content is less than 3 wt%, the adhesion is insufficient, and if it exceeds 50 wt%, the extrusion moldability decreases, and the melt flow rate is less than 0.5 g / 1 om = 300.9 Even if it exceeds /10m, extrusion moldability deteriorates.

In addition, ethylene-acrylic acid ester copolymer or ethylene-methacrylic acid ester copolymer (11: Shiteha), the acrylic ester content or methacrylic ester content is 1 to 30 wt%, preferably 5 to 20 wt%, The melt 70-rate is not particularly limited, but is 0.5 to 1'50.9/iQ mm, preferably 1 to 50 g/10 mw, and preferably 99 to 1% by weight in the resin composition. is 70~]0% by weight.

Note that if the ester content is less than 1 wt%, the adhesion is insufficient, and if it exceeds 30 wt%, the extrusion moldability decreases,
Furthermore, if the melt flow rate is less than 0.5.9/10 mm or exceeds 150.9/IQmm, extrusion moldability will deteriorate.

Examples of acrylic esters include methyl acrylate, ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, etc., and examples of methacrylic esters include methyl methacrylate, ethyl methacrylate, butyl methacrylate, etc., especially methyl acrylate. , ethyl acrylate, and methyl methacrylate are preferred.

This resin composition has insufficient adhesion when the EVA content exceeds 99% by weight, and even when the ethylene-acrylic ester copolymer or ethylene-methacrylic ester copolymer exceeds 99% by weight. Adhesion becomes insufficient.

In addition, examples of the ethylene-α-olefin elastomer include copolymer elastomers of ethylene and α-olefins having 3 or more carbon atoms, copolymer elastomers of ethylene and α-olefins having 3 or more carbon atoms, and dienes. can be mentioned. Examples of ethylene and α-olefin copolymer elastomers having 3 or more carbon atoms include ethylene-propylene elastomers, ethylene-butene-1-ester elastomers, copolymers of ethylene and α-olefins having 3 or more carbon atoms, and hiscyene. Combined elastomers include ethylene-propylene-dicyclopentadiene elastomer, ethylene-propylene-ethylidene norbornene elastomer, ethylene-propylene-1,4-hexadiene elastomer, etc.; Vinyl acetate copolymer, ethylene-acrylic acid ester copolymer, and ethylene-methacrylic acid ester copolymer may be mixed with other resins, fillers, additives, etc. to the extent that they do not practically impede the properties. It's okay.

The ethylene-α-threfin yarn elastomer is subjected to graft modification in the form of a composition with the ethylene-vinyl acetate copolymer/ethylene-acrylic ester copolymer or ethylene-methacrylic ester copolymer resin composition. However, the ratio is 1 to 99 parts by weight for the former and 99 to 1 part by weight for the latter.
Parts by weight.

In either case, 1 part by weight or less or 99 parts by weight or more.
2, the adhesion is insufficient, especially when the amount of plasticizer is 30w.
% or more, the adhesion with vinyl chloride resins becomes insufficient.

000% radical generator per 100 parts by weight of this resin composition
The unsaturated carboxylic acid or its anhydride is graft-modified in the presence of 0.01 to 0.05 parts by weight, preferably 0.05 to 0.03 parts by weight. If the amount of the radical generator is less than 0,001 parts by weight, the adhesion will be insufficient, and if it exceeds 0,000 parts by weight, there is a concern that gel may occur due to crosslinking.

As the radical generator, dicumyl peroxide, benzoyl peroxide, di-t-butyl peroxide, 2,5-dimethyl-2,5-di(1-butylperoxy)hexane, 72.5-dimethyl-2 ,5-di(1
Organic peroxides such as -butylperoxy)hexane-3, lauroyl peroxide, and 1-butylperoxybenzoate are preferably used, and two or more thereof may be used in combination.

Examples of unsaturated carboxylic acids or anhydrides thereof that are monomers used for graft modification include acrylic acid, maleic acid, fumaric acid, itaconic acid, himic acid, and their anhydrides. Maleic acid or hymic anhydride is preferred. Also, two or more types may be combined. Graft modification can be carried out by adding a graft monomer and a radical generator to the above-mentioned resin composition suspended or dissolved in an appropriate solvent, heating and stirring the mixture, or mixing the resin composition with the monomer and radical generator in advance. death,
There is a method of melt-kneading using an extruder, Banbury mixer, kneader, etc., but maleic acid, maleic anhydride,
In the case of graft modification using Himic anhydride or the like as a monomer, the latter method is preferably employed.

The adhesive resin thus obtained of the present invention exhibits particularly excellent adhesive properties in a laminate in which vinyl chloride resin layers or vinylidene chloride resin layers are bonded together, but bonding methods include, for example, coextrusion molding, Any method such as extrusion coating, dry lamination, or various heat welding methods can be used, and it is also possible to obtain a desired laminate with layers of different resins, including a polyolefin thread resin layer, but it is especially important to use separate extruders for each resin. It is economical to obtain a multilayer film, multilayer sheet, multilayer blow bottle, etc. in a desired shape through melt extrusion and coextrusion molding to join each layer inside a circular gouy, T-goo, etc. or immediately after extrusion. preferable.

Molding is possible if the molding temperature is higher than the softening humidity of each resin and lower than the decomposition temperature. In the case of coextrusion molding, it is desirable from the viewpoints of adhesiveness, moldability, and physical properties that the melt viscosities of the resins constituting each layer are not extremely different.

The present invention will be explained in more detail by giving examples and comparative examples below.

Examples 1 to 2 Melt flow rate (JIS K 6730)
12,! 9/1 omm, vinyl acetate content 15%
Ethylene-vinyl acetate copolymer (hereinafter abbreviated as EVA), Melt Flow Ray-1- (JIS K6760)
3, H/1omiyr, methyl acrylate content I Qw
t% of ethylene methyl acrylate copolymer (hereinafter referred to as EM
A), melt flow rate (JISK6758
)3.1. ! ? /10ml71 and fish fin> Content 2
8 mol% ethylene-propylene elastomer (hereinafter referred to as
(abbreviated as EPR) was mixed in a Henschel mixer in the proportions shown in Table 1, and 0.014 parts by weight of G-t-butyl peroxide was added to this, based on 00 parts by weight of the above resin composition, to make the pellet surface uniform. After soaking it in water, add 0 maleic acid.
8 parts by weight were added to form a mixture using a Henschel mixer, and this was melt-mixed and extruded at 200°C using a 40 mm extruder to obtain a graft-modified adhesive resin.

Next, using a coextrusion film molding device, this graft modified adhesive resin was heated to a cylinder temperature of 180'C and a temperature of 1
At 85°C, polyvinyl chloride resin (hereinafter abbreviated as PVC) containing 45% by weight of DOP' (dioxylphthalate +-) was heated at a cylinder temperature of 170°C and a die temperature of 85°.
Two-layer coextruded film with C (adhesive resin layer 30μ thick, P
A VC layer (50μ thick) was obtained.

Table ] This coextruded film II] ], 5 mmz length]
, cut into 5 cm pieces, forcibly peeled off one end, and using a Tensilon type tensile tester, the tensile speed was 100 m17/m1I.
Peel strength was measured under Iz 180 degree peeling conditions. The results are also shown in Table 1, and the peel strength was high in all cases.

Comparative Examples 1 to 5 EVA/EMA compositions and EPR were compared to Comparative Examples 1 to 5 in Table 1.
A graft-modified resin was obtained in the same manner as in Examples 1 to 2, except that the proportions shown in 5 were used, and PV
A two-layer film was made with C and the peel strength was measured. The results are also shown in Table 1, and the peel strength was low in all cases.

Examples 13-21 Melt flow rate (JIS K6730) 20.
9/lQmm, ffr containing vinyl acetate, ], 88wt
EVAl Melt Flow Ray) (JIS K676
Q): 19/10ml methyl methacrylate content 1-8
wt% of ethylene-methyl methacrylate-1 cofj combination (hereinafter abbreviated as EMMA), and butene-1 content of 10 mol% as an ethylene-α olefin elastomer,
Melt 70-1/-1・(JIS I(6760)3
．． 6. @/IQmLn, = c tyrene - phthene 1 elas l"v- (hereinafter abbreviated as EB) in Examples 13 to 2 of Table 2
] Graft-modified resins were obtained in the same manner as in Examples J to 12, except that the proportions not shown were used, and a two-layer film with PVC was similarly made using a coextrusion molding machine, and the peel strength was measured. The results are also shown in Table 2, and the peel strength was high in all cases.

Comparative Examples 6 to 9 Graft modified resins were obtained using the resin compositions of Comparative Examples 6 to 9 shown in Table 2 in the same manner as Comparative Examples 1 to 5, and the interlayer peel strength of the two-layer film with I) VC was measured in the same manner as in Comparative Examples 1 to 5. did. The results are also shown in Table 2, and the peel strength was lower than in Examples 13-21.

Claims (1)

[Claims] (]) 6ffi vinyl-containing B1.3-50 wt% ethylene-vinyl acetate copolymer 1-99 wt% and acrylic ester or methacrylic ester content 1-30 wt%
wt% ethylene-acrylic ester copolymer or ethylene-methacrylic ester copolymer 99-1% by weight
0.001 parts by weight of the radical generator per 100 parts by weight of the resin composition consisting of 1 to 99 parts by weight of the resin composition and 99 to 1 part by weight of the ethylene-α olefin elastomer.
An adhesive resin obtained by graft-modifying an unsaturated carboxylic acid or its anhydride in the presence of 0.5 parts by weight. (2) Ethylene with a vinyl acetate content of 3 to 50 wt%
Vinyl acetate copolymer 1 to 99% by weight and ethylene-acrylic ester copolymer or ethylene-acrylic ester containing 1 to 30% by weight of acrylic ester or methacrylic ester.
Resin composition 10 consisting of 1 to 99 parts by weight of a resin composition comprising 99 to 1% by weight of a methacrylic acid ester copolymer and 99 to 1 part by weight of an ethylene-α olefin elastomer
An adhesive resin layer and a vinyl chloride resin layer or a vinylidene chloride resin layer formed by graft-modifying an unsaturated carboxylic acid or its anhydride in the presence of 0.001 to 0.05 parts by weight of a radical generator based on 0 parts by weight. A laminate consisting of.