JPS6015409A - Adhesive polyolefin composition - Google Patents

Abstract

PURPOSE:The titled composition excellent in adhesiveness, odor, color, etc., obtained by modifying a polyolefin with an unsaturated carboxylic acid (anhydride) and a polyol compound (fatty acid ester) and using the modified polyolefin as a principal component. CONSTITUTION:A polyolefin such as polyethylene or polypropylene is modified with an unsaturated carboxylic acid (anhydride), e.g., acrylic acid or maleic anhydride, and the product is further modified with a polyol compound having at least two hydroxyl groups (e.g., polyoxyethylene glycol or trimethylolpropane) and, optionally, a fatty acid ester of a polyol compound to prepare a modified polyolefin. The purpose adhesive polyolefin composition is obtained by mixing the modified polyolefin with, optionally, an antioxidant, pigment, antiblocking agent, inorganic filler, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to polyolefin compositions with improved adhesion.

Although polyolefins have excellent mechanical, thermal, and chemical properties, they are nonpolar materials, so they are
It has poor adhesion to metal materials such as aluminum and polar polymers such as nylon, polyester, and polyurethane, limiting its applications. For this reason, a method of graft copolymerizing unsaturated carboxylic acids such as acrylic acid and maleic anhydride or their anhydrides has been proposed for the purpose of improving adhesion, and some results have been obtained. Currently, a wide range of shortcomings have been pointed out, including a lack of water, odor, and poor color tone.

As a result of various studies aimed at improving these problems, the present inventors found that a polyolefin composition obtained by modifying polyolefin with a specific compound exhibits excellent adhesion to various materials, and has no odor or odor. The present invention was achieved by discovering that it has comprehensively balanced physical properties including color tone.

That is, the present invention relates to an adhesive mainly composed of a modified polyolefin obtained by modifying a polyolefin with an unsaturated carboxylic acid or its anhydride, a polyol compound having two or more hydroxyl groups in the molecule, and optionally a fatty acid ester of a polyionyl compound. polyolefin composition.

The polyolefin composition according to the present invention has strong adhesion to metal materials such as iron and aluminum, polar polymers such as nylon, polyester, and polyurethane, and inorganic materials such as talc and glass, but particularly has strong adhesion to polyurethane. Even in the so-called injection foam molding method, in which a urethane material is injected into a polyolefin molded product and foam molded, it has excellent properties of exhibiting strong adhesion at temperatures below the softening point of the polyolefin.

In addition to this adhesive performance, this polyolefin has an excellent overall balance, with unpleasant odors being significantly reduced not only at room temperature but also during relatively high-temperature processing, and color deterioration of molded products less likely to occur. A composition is obtained according to the invention.

Examples of the polyolefin used in the present invention include homopolymers of ethylene or propylene, random and block copolymers of ethylene and propylene, copolymers of ethylene and propylene and/or α-olefins having 4 or more carbon atoms, or Copolymers of ethylene and unsaturated compounds such as vinyl acetate, acrylic esters and methacrylic esters are preferred. Although these polyolefins can be used alone, it is also possible to use two or more types.

Further, the unsaturated carboxylic acids and their anhydrides used in the present invention include, for example, unsaturated monocarboxylic acids such as acrylic acid and methacrylic acid, unsaturated dicarboxylic acids such as maleic acid, fumaric acid, and itaconic acid, and maleic anhydride. Anhydrides such as itaconic anhydride and himic anhydride.

Among these compounds, maleic anhydride is particularly preferred).

Examples of the polyol compound having two or more hydroxyl groups in the molecule used in the present invention include one type or a mixture of two or more types selected from the following compounds.

(1) Polyoxyethylene glycol, polyoxypropylene glycol, and polyoxyethylene-oxydipropylene glycol with a molecular weight of 8,000 or less. (2) Ethylene oxide in polyols such as chrycerin, trimethylolethane, trimethylolpropane, pentaerythritol, and sorbitol. And/or the molecular weight obtained by addition polymerization of propylene oxide is F3o
Compounds below oo (8) Ethylene glycol, propylene glycol,
Polyglycerin such as glycerin, trimethylolethane, trimethylolpropane, pentaerythritol, sorbitol, diglycerin condensed with glycerin, triglycerin, and tetraglycerin. Among these compounds, trimethylolethane, trimethylolpropane, and glycerin contain ethylene oxide and/or Or polyols with a molecular weight of 1000 or less obtained by addition polymerization of propylene oxide are particularly preferred. In addition, as fatty acid esters of polyols, esters of saturated or unsaturated carboxylic acids having 22 or less carbon atoms and the above polyols are used, such as polyols and caproic acid, 2-ethylhexanoic acid, lauric acid, stearic acid, behenic acid, oleic acid, etc. Examples include mono- and diesters of acids, erucic acid.

Among these compounds, preference is given to using monoester compounds.

The modified polyolefin of the present invention can be obtained by first modifying a polyolefin with an unsaturated carboxylic acid or its anhydride by a known method, and then modifying it with a polyol compound and optionally a fatty acid ester of the polyol compound. It is also possible to obtain 'C' by simultaneously modifying a polyolefin with an unsaturated carboxylic acid or its anhydride, a polyol compound, and optionally a fatty acid ester of the polyol compound.

As a method for modifying polyolefin with an unsaturated carboxylic acid or its anhydride, a method of reacting in a homogeneous or heterogeneous system using a radical initiator in an organic solvent (for example, Japanese Patent Publication No. 44-15422, Japanese Patent Publication No. 52-80546, (Japanese Patent Publication No. 54-80715, etc.) or i, a method of melt-kneading a polyolefin and an unsaturated carboxylic acid or its anhydride in the presence or absence of a radical initiator using a Banbury mixer 1 heated roll, screw extruder, etc. (for example,
JP 52-21042, JP 51-10265,
QB946,884, JP-A-55-16022). A method for simultaneously modifying a polyolefin with an unsaturated carboxylic acid or its anhydride, a polyol compound, and optionally a fatty acid ester of the polyol compound may be carried out in the same manner as above. In order to further modify a polyolefin that has been modified with an unsaturated carboxylic acid or its anhydride with a polyol compound and optionally a fatty acid ester of a polyol compound, a liquid polyol compound or a fatty acid ester of a polyol compound is added to a powder of the polyolefin. This is carried out by bringing the pellets into contact with each other, or by bringing the polyolefin powder or pellets into contact with a water or organic solvent solution of a polyol compound and, in some cases, a fatty acid ester of the polyol compound. At this time, the temperature can be usually from room temperature to about 200°C. Also,.

The contact may be carried out by mixing in a container or by the above-mentioned melt mixing.

In addition, the proportion of each modifying component is usually 0.0 parts by weight of unsaturated carboxylic acid or its anhydride per 100 parts by weight of polyolefin.
1 to 5 parts by weight, preferably 0.05 to 2 parts by weight, particularly preferably 0.1 to 1 part by weight, the polyol compound is o, o
The amount of i-io is preferably 0.05 to 5, and the fatty acid ester of the polyol is preferably 0.01 to 2 parts by weight, particularly preferably 1 part by weight or less. If the amount of the unsaturated carboxylic acid or its anhydride is less than 0.011 parts by weight, the adhesiveness will be insufficient, and if it is more than 5M parts, no improvement in the adhesiveness can be expected and the cost will be high.

If the amount of the polyol compound is less than 0.01 parts by weight, the effect of improving adhesion is insufficient, and if it is more than 0 parts by weight of IO, bleeding to the surface of the polyolefin molding will be severe, deteriorating the appearance of the product, and the physical properties of the polyolefin will significantly deteriorate. Undesirable.

Fatty acid esters of polyol compounds are acrylic resins,
It is desirable to use a small amount of resins containing polar groups, such as polyester resins and polyurethane resins, since this increases adhesiveness. Furthermore, the fatty acid ester of the polyol compound also has a corrosion inhibiting effect on metal materials.

If the amount of fatty acid ester in the polyol compound exceeds 2 parts by weight, it is undesirable because it bleeds onto the surface of the polyolefin molded product, impairing the product's appearance and deteriorating its physical properties. When using a fatty acid ester of a polyol compound, it is preferable from the viewpoint of bleeding and physical properties that the total amount of the polyol compound and the fatty acid ester of the polyol compound does not exceed 10 parts by weight.

The polyolefin composition of the present invention is a composition mainly composed of the modified polyolefin obtained in this way, and also contains commonly used oxidation-preventing agents, copper-damage inhibitors, lubricants, anti-brogging agents, etc. Various additives, pigments, talc,
Inorganic fillers such as mica, calcium carbonate, etc. can be added. It is also possible to add unmodified polyolefin resins.

As such a polyolefin resin, the same polyolefin as used for the above-mentioned modified polyolefin can be used.

The present invention will be specifically explained below using Examples and Comparative Examples, but the present invention is not limited thereto.

Example 1 Ethylene-containing fi 7. Ethylene-propylene block copolymer with Owt%, melt index lt (MFI) 2 (manufactured by Jumin Chemical Co., Ltd., Jumin Noprene ■) IKf
As a polyol, it has 8 terminal hydroxyl groups and has an average molecular weight of M80.
0 polyoxyethylene polyol 5F, maleic anhydride 4F, and 0.5 g of 2.5-dimethyl-2,5-di-t-butylperoxyhexane as a radical initiator were added and mixed thoroughly with a Shiba mixer. The MFI=
85 white pellets were obtained. This at 200°C150K
A sheet of 10×10t1n was prepared by pressing for 5 hours under 9 conditions of p/J.

The obtained sheet was placed on a hot pot kept at 40°C, a cylindrical polyethylene mold with a diameter of 5 crn was placed on the sheet, and a urethane blowing agent (MDI/polyol/Freon mixture) was injected into the mold. The foam was allowed to harden for 10 minutes. (The composition of the foaming agent was adjusted so that the foaming ratio of polyurethane foam was 40 times.) Ten minutes after injection, the sheet was peeled off from the foam material by hand and the adhesive strength was determined. Cohesive failure of the urethane foam was observed on the entire surface, indicating good adhesion. In addition, as an odor test, the pellets were placed in a 50CH Erlenmeyer flask and heated in a water bath for 80°C for 15 minutes, and then the odor was confirmed in the field, and no irritating odor was detected.

Examples 2 to 5 and Comparative Examples 1 to 2 In Example 1, only the amount of polyol added was 1.8.10
The mixture was kneaded and granulated using an 80m single-screw extruder with the temperature changed to 80f to obtain white pellets. These were subjected to an adhesion test with polyurethane foam and an odor test in the same manner as in Example 1. Further, the ratio axis was determined using the same procedure for Comparative Example 1 in which only the polyol was removed from the conditions of Example 1, and Comparative Example 2 in which only maleic anhydride was removed. The results are shown in Table 1.

Table 1 * Amount based on 100 parts by weight of polyolefin (same below) Examples 6 to 7 Polypropylene 50F/ grafted with maleic anhydride obtained in Comparative Example 1 was heated with 1 each of water and xylene as a heating medium, and heated at 100° After stirring at C, 0.51 of each of the polyols used in Example 1 was added and treated for 4 hours. After the treatment was completed, the treated polymers were thoroughly rinsed with each hot medium and dried.The treated polymers were tested for adhesion to polyurethane foam in the same manner as in Example 1. The results are shown in Table 2. 8- It can be concluded that there is no difference in the effect of C after changing the denaturation method.

Table 2 Examples 8 to 14 Evaluations were carried out in the same manner as in Example 1 except that the type of polyol component and the formula 1 were changed as shown in Table 3. The results are shown in Table 3.

Table 8 E Polyoxypropylene polyol with 3 terminal hydroxyl groups and average molecular weight J14.40** Polyoxyethylene-propylene polyol with 8 terminal hydroxyl groups, average molecular weight 8000, and ethylene oxide content in the molecule of 30% Examples 15 to 18 For 100 parts by weight of a modified polyolefin obtained by modifying a polyolefin with acrylic acid or maleic anhydride, a polyol or a polyol and its fatty acid ester was added at the blending ratio shown in Table 4, in the case of an ethylene polymer, at 80°C. In the case of propylene-based polymers, Polyurekne adhesiveness and odor tests were conducted on the polymers obtained by extruding them at 230° C. using a 30-mole single-screw extruder.

The results are shown in Table 4.

Examples 19 to 21, Comparative Examples 3 to 5 The modified polypropylene obtained in Examples 1 and 11 was
A pressed sheet with a thickness of 0.30 was prepared by hot pressing for 5 minutes under conditions of 50 h/cr/I. Press sheets were prepared in the same manner. These press sheets were used as adherends and 〈(soft aluminum E)&(o, a
rnm thickness), iron plate (0.2rcn thickness), J: Sandwiched between stainless steel plates (0.1IIIrn thickness) and crimped with a hot press for 5 minutes at 280'C, IQKri/cnl, then T. The mold peel strength was measured. 5th result
Shown in the table.

No. 5 Surface treatment of coating materials Degrease the surface with an equal volume mixture of ton/toluene

Claims (1)

[Claims] A modified polyolefin obtained by modifying a polyolefin with an unsaturated carboxylic acid or its anhydride, a polyol compound having two or more hydroxyl groups in the molecule, and optionally a fatty acid ester of the polyol compound, an adhesive polyolefin whose main component is f. Composition.