JPH0881663A - Adhesive - Google Patents

Abstract

PURPOSE: To obtain an adhesive excellent in chemical resistance and compatibility and capable of well bonding a polyester resin molded product with a polyamide molded product by compounding a specific amount of an aromatic polyester with specific amounts of specified polymers. CONSTITUTION: This adhesive comprises (A) 100 pts.wt. of an aromatic polyester, (B) 10-100 pts.wt. of an aliphatic polyamide having a ratio of 6-12 between the methylene group number and the amide group number in the main chain of the polymer and (C) 5-100 pts.wt. of a modified polyolefin. The component A is preferably the mixture of (i) polytetramethylene terephthalate with a copolyester containing (ii) terephthalic acid and (iii) an aliphatic dicarboxylic acid as the acid components wherein the content of the component (ii) is >=50mol.% based on the whole acids in the mixture of the component A, and the component C is preferably polypropylene containing glycidyl groups and acid anhydride groups in amounts of 1-10wt.% and 0.05-1wt.%, respectively.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an adhesive, and more particularly to an aromatic polyester-based adhesive capable of favorably adhering a polyester resin molded product and a polyamide resin molded product.

[0002]

2. Description of the Related Art Polyester resins and polyamide resins are both useful as engineering plastics, but since they have both advantages and disadvantages, they are used for applications with suitable characteristics.

For example, polyester resins are generally excellent in heat resistance and chemical resistance, but inferior in toughness and hydrolysis resistance.
Polyamide resin is excellent in flexibility, toughness, hydrolysis resistance, etc., but is inferior in heat aging resistance, chemical resistance, weather resistance, etc., and also changes in characteristics due to moisture absorption.

The use of a molded article in which these polyester resin and polyamide resin are compounded is a very useful means because the advantages of both can be utilized and the drawbacks can be compensated for.

Compounding a polyester resin with a polyamide resin is described in European Patent Application Publication No. 0,336.
An example is a two-layer tubular product formed by extrusion molding of No. 806 polytetramethylene terephthalate and nylon (PA) 12.

However, since the polyester resin and the polyamide resin have different properties, there is a problem in that the adhesiveness at the interface between the two is poor when the molded products are compounded in this way. And as these adhesives, German Patent No. 3,8
It has been proposed to use polyvinyl alcohol in 27,092, functionalized polyolefins in EP-A-0,287,839, and in JP 6-099553 a mixture of polyester and polyamide. .

However, these adhesives have problems in molding and use due to inferior heat resistance and chemical resistance, and in the production of adhesives due to poor compatibility between polyester and polyamide. Problems have not been resolved.

[0008]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object thereof is to obtain an adhesive for polyester resin / polyamide resin which is excellent in heat resistance, chemical resistance and compatibility.

[0009]

The present inventors have conducted intensive studies to obtain an adhesive satisfying the above-mentioned properties, and as a result, found that a composition obtained by blending an aromatic polyester with a specific polymer in a specific amount meets the above-mentioned object. The present invention has been reached.

That is, the adhesive of the present invention comprises 10 to 100 parts by weight of an aliphatic polyamide (B) in which the ratio of the number of methylene groups to the number of amide groups in the polymer main chain is 6 to 12 per 100 parts by weight of the aromatic polyester (A). Parts and 5 to 100 parts by weight of (C) modified polyolefin.

The present invention will be described.

The aromatic polyester of the component (A) used in the present invention has an acid component of phthalic acid derivative such as terephthalic acid, isophthalic acid, phthalic acid, methylterephthalic acid, methylisophthalic acid; 2,6-naphthalenedicarboxylic acid. One or more aromatic dicarboxylic acids selected from naphthalenedicarboxylic acids such as acids, 2,7-naphthalenedicarboxylic acid, 1,4-naphthalenedicarboxylic acid, and 1,5-naphthalenedicarboxylic acid, and derivatives thereof, The diol component is one or more of aliphatic diols such as ethylene glycol, propylene glycol, tetramethylene glycol, hexamethylene glycol, neopentyl glycol, polyoxyalkylene glycol represented by polyethylene glycol and polytetramethylene glycol. Homopolymer of polyester, one of the copolymers and their mixture of two or more of the main component.

The aromatic polyester preferably contains 50 mol% or more of an aromatic dicarboxylic acid component as an acid component and 95 mol% or more of an aliphatic diol as a diol component.

When the aromatic polyester component is a mixture of two or more polymers, the ratio of the acid and diol components in all the components is preferably within the above range.

The acid component copolymerized with the above-mentioned aromatic dicarboxylic acid in this aromatic polyester is an aliphatic or fatty acid such as succinic acid, adipic acid, sebacic acid, azelaic acid, decanedicarboxylic acid or cyclohexanedicarboxylic acid. Cyclic dicarboxylic acids are preferred.

As the diol component, hydroquinone,
Obtained from dihydroxybenzene and its derivatives such as resorcin; bisphenol compounds such as 2,2-bis (4-hydroxyphenyl) propane and 2,2-bis (4-hydroxyphenyl) sulfone; bisphenol compounds and glycols such as ethylene glycol Aromatic diols such as ethers and diols can be copolymerized in a range of less than 5 mol%.

As the aromatic polyester of the component (A) of the present invention, polytetramethylene terephthalate, polyethylene terephthalate, polyethylene terephthalate, from the viewpoint of heat resistance and chemical resistance.
Polytetramethylene-2,6-naphthalenedicarboxylate and polyethylene-2,6-naphthalenedicarboxylate are preferable, and polytetramethylene terephthalate is particularly preferable.

When polytetramethylene terephthalate and a copolyester composed of terephthalic acid and an aliphatic dicarboxylic acid as an acid component are mixed and used, the polytetramethylene terephthalate is adhered while maintaining its heat resistance and chemical resistance. The effect that the power is improved appears. A mixture of polytetramethylene terephthalate and a copolymerized polyester composed of terephthalic acid as an acid component and an aliphatic dicarboxylic acid is mixed so that the proportion of terephthalic acid in all acid components is 50 mol% or more.

The aromatic polyester used in the present invention has an intrinsic viscosity of 0.5 or more when measured at 35 ° C. with o-chlorophenol.

The aromatic polyester used in the present invention can be produced by a usual production method, for example, a melt polycondensation reaction or a method in which this is combined with a solid phase polycondensation reaction. For example, a production example of polytetramethylene terephthalate will be described. In the presence of a catalyst, terephthalic acid or its ester-forming derivative (for example, lower alkyl ester such as dimethyl ester, monomethyl ester) and tetramethylene glycol or its ester-forming derivative are used. Polytetramethylene terephthalate can be produced by a method in which a glycol ester of terephthalic acid obtained by heating and reacting is polymerized to a predetermined degree of polymerization in the presence of a catalyst.

The aliphatic polyamide having a ratio of the number of methylene groups to the number of amide groups in the polymer main chain of the component (B) used in the present invention is 6 to 12 includes nylon 11, nylon 12, nylon 69, nylon 610, nylon. 61
1, nylon 612, nylon 613 and the like.

These polyamides can be easily obtained by condensation polymerization of the corresponding diamine and dicarboxylic acid, condensation polymerization of the corresponding aminocarboxylic acid, or ring-opening polymerization of the corresponding cyclic lactam. It may be a copolymer of the amide or ester-forming compound.

Among these aliphatic polyamides, nylon 12 and nylon 11 are particularly preferable.

When the ratio of the number of methylene groups to the number of amide groups in the polymer main chain is less than 6, the crystallinity increases,
If this ratio is greater than 12, the number of amide groups that contribute to adhesion decreases, and the adhesion effect decreases.

The amount of the aliphatic polyamide having a ratio of the number of methylene groups to the number of amide groups in the polymer main chain of the component (B) used in the present invention of 6 to 12 is 100 parts by weight of the aromatic polyester of the component (A). 10 to 100 parts by weight. If the amount is less than 10 parts by weight, the adhesive strength will not be sufficiently exhibited, and if it is more than 100 parts by weight, the composition will be difficult to extrude.

The polyolefin as the raw material of the modified polyolefin of the component (C) used in the present invention is a polymer containing the main polyolefin component in an amount of 50 mol% or more, preferably 80 mol% or more, or a random or block with another polyolefin component. Copolymers can be used. The main polyolefin component is ethylene, propylene, 1-butene, 3-methyl-1-butene, 1-pentene, 4-methyl-1-pentene, 1-hexene, 5
-Methyl-1-hexene and the like can be mentioned.

The following general formula (I)

[0028]

Embedded image

(In the formula, R1 to R4 are hydrogen or carbon number 1
Is an alkyl group of 6 and n represents an integer of 1 to 20. The thing which copolymerized the non-conjugated diene represented by these can also be used. Here, as the non-conjugated diene comonomer, 2-methyl-1,4-pentadiene, 1,4-hexadiene, 4-methylidene-1-hexene, 4-methyl-1,4-hexadiene, 5-methyl-1, 4-hexadiene, 1,4-heptadiene, 4-ethyl-1,4
-Hexadiene, 4,5-dimethyl-1,4-hexadiene, 4-methyl-1,4-heptadiene, 4-ethyl-1,4-heptadiene, 5-methyl-1,4-heptadiene, 5-methyl-1 , 4-octadiene, 1,5-
Heptadiene, 1,5-octadiene, 5-methyl-
1,5-heptadiene, 2-methyl-1,5-hexadiene, 1,6-octadiene, 6-methyl-1,6-octadiene, 7-methyl-1,6-octadiene, 2-
Methyl-1,6-heptadiene, 1,9-decadiene,
1,13-tetradecadiene and the like can be mentioned. Of these, 1,4-hexadiene, 2-methyl-1,5-hexadiene, 7-methyl-1,6-octadiene, 1,
9-decadiene, 1,13-tetradecadiene and the like are desirable. Two or more kinds of these non-conjugated diene comonomers may be used.

In order to randomly copolymerize the polyolefin with the non-conjugated diene comonomer, a general copolymerization method using a Ziegler-Natta catalyst may be applied. In this case, the proportion of the non-conjugated diene is preferably 10 mol% or less.

The modified polyolefin used in the present invention is modified by introducing a compound having a glycidyl ether group into the polyolefin main chain by a method such as copolymerization or grafting.

By using this modified polyolefin, the ratio of the number of methylene groups to the number of amide groups in the polymer main chain of the component (A) and the component (A), which are essentially incompatible, is 6 to 12. By compatibilizing the aliphatic polyamide, it becomes possible to perform extrusion in a good state.

When an acid anhydride group is introduced together with the glycidyl ether group, the compatibilizing effect between the component (A) and the component (B) is significantly enhanced.

The modified amount of the modified polyolefin of the component (C) used in the present invention is such that the glycidyl ether group is 1 to 1
0% by weight, and 0.05 to 1% by weight when an acid anhydride is used in combination. When the amount of modification of both is smaller than this range, the above-mentioned compatibilizing effect is not sufficiently exhibited, and when it exceeds this range, problems such as thickening occur during processing in a molten state.

The amount of the modified polyolefin as the component (C) used in the present invention is 5 to 100 parts by weight per 100 parts by weight of the aromatic polyester as the component (A). If the blending amount is less than 5 parts by weight, the compatibilizing effect is small, and if it is more than 100 parts by weight, the compatibility with the aromatic polyester as the component (A) becomes poor and peeling phenomenon or the like occurs on the surface layer. Therefore, it is not preferable.

Other compounding agents such as stabilizers and processing aids may be added to the adhesive of the present invention.

In the adhesive of the present invention, it is preferable that these compounding components are uniformly dispersed. A known method can be used for the compounding method. For example, all or part of the compounding ingredients are fed all at once or dividedly into a heated single-screw, twin-screw, etc. extruder and homogenized by melt-kneading, and then the molten composition extruded into a wire is cooled and solidified. Then, there is a method of granulating by cutting to a desired length, but a method using another mixer such as a blender, a kneader, or a roll may be used. Further, it is also possible to use a combination of these means, or a method of sequentially adding the blended components by repeating a plurality of times, and the like.

The adhesive of the present invention thus obtained can bond polyester resin and polyamide resin well. The method of bonding is not particularly limited, and is a one-step method such as multi-component injection molding or coextrusion molding, or press molding after first forming a bonded article.
A multi-step method of adhering by injection molding, extrusion molding or the like can be adopted.

The polyester resin and the polyamide resin to be adhered may be resins mainly composed of a polymer composed of a polyester unit and a polyamide unit, respectively.

[0040]

EXAMPLES The present invention will be described in detail below with reference to examples.

Adhesiveness in the examples is measured by molding a polyester resin and a polyamide resin (thickness: 0.5 to 1 m).
sheet adhesive (thickness 0.5 to 1 mm) is sandwiched between m), the sample is inserted between the press molding machine and 250 ° C.
Were heated for 5 to 10 minutes, and pressure was applied by pressing when they were in a molten state.

After cooling, the peeled state when the polyester resin layer and the polyamide resin layer were peeled off was observed.

[Materials used] (1) Polytetramethylene terephthalate (PBT) ...
Using o-chlorophenol as a solvent, P having an intrinsic viscosity of 0.88 measured at 35 ° C. with an Ostwald viscosity tube
BT polymer (manufactured by Teijin Limited). (2) Polytetramethylene-2,6-naphthalenedicarboxylate (PBN) ... PBN polymer having an intrinsic viscosity of 0.77 measured by an Ostwald viscosity tube at 35 ° C. using o-chlorophenol as a solvent (Teijin )
Made). (3) PA11 ... “Rilsan BMN 0” Toray Industries, Inc.
Made. (4) PA12 ... “Daiamide L1600” manufactured by Daicel Huls Co., Ltd. (5) PA636 ... "PRIADIT 2054" manufactured by Unichema, the Netherlands. (6) Modified PP ... “Tonen CMP HA300” manufactured by Tonen Chemical Co., Ltd. (7) Copolyester 1 ... 60/40 mol% of terephthalic acid / adipic acid as an acidic component and 30/58/12 mol% of ethylene glycol / 1,4-butanediol / polytetramethylene glycol as a glycol component
Polyester polymerized in the proportion of. (8) Copolymerized polyester 2 ... A polyester obtained by polymerizing terephthalic acid / isophthalic acid as an acid component at 50/50 mol% and ethylene glycol / neopentyl glycol as a glycol component at a ratio of 45/55 mol%.

[Examples 1 to 10 Comparative Examples 1 to 6] 130
PBT having an intrinsic viscosity of 0.88, which was dried with hot air at 8 ° C.
PA12, modified PP and copolymerized polyesters 1 and 2 were mixed in advance in a tumbler at a ratio shown in Table 1, and then a cylinder temperature of 250 was obtained while drawing vacuum using a vented twin-screw extruder with a screw diameter of 44 mm. Melt kneading was carried out at a temperature of 160 ° C., a screw rotation speed of 160 rpm, and a discharge rate of 50 kg / hr, and a thread discharged from a die was cooled and cut to obtain an adhesive pellet.

This adhesive pellet was used to press 2 with a press molding machine.
After heating at 50 ° C., pressure was applied to form a sheet.

PBT, PBN and PA11 (nylon 1
The molded article for the adhesion test of 1) had a cylinder temperature of 250 to 280 ° C. and a mold temperature of 6 with an injection molding machine having an injection capacity of 5 ounces.
0-80 ° C, injection pressure 60 MPa, cooling time 12 seconds,
And a thickness of 0.7 mm under the condition that the entire molding cycle is 40 seconds
The molded product of was molded.

Adhesion was measured using these samples. The results are shown in Table 1.

[0048]

[Table 1]

In the case of the composition in which the modified PP or the copolyester is blended with PBT, it adheres to the PBT molded product, but PA1
No adhesion to 1 molded product (Comparative Examples 2 to 3). P to PBT
With the composition containing A12, the adhesiveness with the PA11 molded product is slightly improved, but it is difficult to extrude the adhesive due to poor compatibility with both (Comparative Example 1). But PB
When modified PP is blended in addition to T and PA12, the extrudability of both is significantly improved, and good adhesion is exhibited for both PBT molded products and PA11 molded products (Comparative Example 4, Example 1). ~ 4). Furthermore, when PBT and copolyester are used together as the polyester component of the adhesive,
Even when the blending amount of PA12 is small, higher adhesive strength can be obtained (Examples 6 to 10). This composition also exhibits good adhesiveness to a PBN resin molded product, which has a higher crystallinity than PBT and is considered to be difficult to bond as a polyester resin molded product (Examples 5 and 7). When PA636 is used as the component of the adhesive, the high adhesive strength as when PA12 is used cannot be obtained (Comparative Examples 5 to 5).
6).

Claims (4)

[Claims] 1. An aliphatic polyamide 10 to 100, wherein the ratio of the number of methylene groups to the number of amide groups in the polymer main chain (B) is 6 to 12 per 100 parts by weight of the aromatic polyester (A).
An adhesive obtained by mixing 5 parts by weight and (C) 5 to 100 parts by weight of the modified polyolefin. 2. The adhesive according to claim 1, wherein the aromatic polyester as the component (A) is polytetramethylene terephthalate. 3. An aromatic polyester as component (A), which is a copolymerized polyester comprising polytetramethylene terephthalate and terephthalic acid as an acid component and an aliphatic dicarboxylic acid, and terephthalic acid in all acid components of the aromatic polyester mixture. Of 50 mol% or more,
The adhesive according to claim 1, which is a mixture. 4. The modified polyolefin as the component (C) has a glycidyl ether group content of 1 to 10% by weight and an acid anhydride group content of 0.05.
1. A polypropylene containing 1% by weight.
The adhesive according to any one of 3 above.