JPS5813643A - Polyolefin composition - Google Patents

Abstract

PURPOSE:To provide a composition having remarkably improved adhesivity, little odor, and improved color tone, by compounding a hydrotalcite compound to a polyolefin modified by graft polymerization; CONSTITUTION:To objective composition is prepared by compounding (A) 100pts.wt. of a polyolefin modified with an unsaturated carboxylic acid or an unsaturated carboxylic acid anhydride or a mixture of said modified polyolefin with unmodified polyolefin with (B) 0.01-30pts.wt., preferably 0.05-1.0pt.wt. of a hydrotalcite compound. The polyolefin in the component (A) is a low-density or high-density ethylene homopolymer having a molecular weight of 50,000- 300,000. The unsaturated carboxylic acid and its anhydride are preferably maleic acid and maleic anhydride.

Description

DETAILED DESCRIPTION OF THE INVENTION q] OBJECTS OF THE INVENTION The present invention relates to polyolefin compositions. More specifically, regarding a polyolefin composition comprising (A) a polyolefin modified with an unsaturated carboxylic acid or an unsaturated carboxylic acid anhydride and a (Bl 8 hedrotalcite-based compound), a composition that dramatically improves adhesiveness. The purpose is to provide something.

BACKGROUND OF THE INVENTION Polyolefins are widely produced industrially and used in many fields because they have excellent mechanical, thermal, chemical, and electrical properties, are easy to process, and are inexpensive resins. has been done.

However, since it is a non-polar resin due to its chemical structure, iron,
Composite materials and laminates with metals such as aluminum and alloys containing these as main components, polar polymers such as nylon and ethylene-vinyl alcohol copolymers, and inorganic materials such as talc, mica, and gas. It has the disadvantage of poor adhesion during manufacture.

For this reason, methods for imparting adhesive properties have been developed. Typical methods include discharge treatment using corona discharge, random copolymerization with vinyl monomers having polar groups, and graft copolymerization of unsaturated organic compounds with polar groups such as unsaturated carboxylic acids onto the surface of polyoleain. Examples include methods of denaturing by polymerization and the like. Among these methods, many methods of graft polymerizing unsaturated carboxylic acids or their anhydrides have been proposed and are widely applied. According to this method, adhesiveness to metal materials, organic materials, and inorganic materials can be imparted to the polyolefin without impairing the above-mentioned excellent properties originally possessed by polyolefin. Addition of metal compounds, addition of polymeric compounds such as elastomers, etc. have been developed for the purpose of further improving the adhesion of the grafted material obtained by this method. I haven't gotten anything.

In addition, the modified polyolefin Furthermore, it becomes a problem when used as a food packaging material. Further, during denaturation, the color tone may deteriorate, which may impair the appearance of the product.

l Structure of the Invention Based on the above, the present inventors have conducted various searches to improve the drawbacks (problems) of polyolefins modified by graft polymerization, and have found that (A) [unsaturated carboxylic acid or unsaturated carboxylic acid] A polyolefin composition consisting of a polyolefin modified with anhydride (hereinafter referred to as "modified polyolefin") or the modified polyolefin, 100 parts by weight of the polyolefin, and (B) 001 to 30 parts by weight of a hydrotalcite compound has been dramatically improved. They found that not only the adhesion was improved, but there was almost no odor, and the color tone was also improved.
We have arrived at the present invention.

■　Effects of the invention.

The composition obtained according to the present invention has the following effects (characteristics) in order to significantly improve the above-mentioned problems that the compositions obtained by conventional methods had. ing.

(1) Metals such as iron, aluminum, copper, lead, zinc, tin, apricot, and nickel, as well as alloys containing these as main components (e.g., stainless steel, brass), nylon, ethylene-vinyl alcohol copolymer Combined, polyethylene terephthalate, polybutylene terephthalate,
Polymers with polar groups such as polymethyl methacrylate, polyacetal, cellulose acetate, cellulose nitrate, polyurethane, chloroprene rubber, acrylic ester rubber and acrylonitrile-butadiene rubber (NBR) and inorganic materials such as mica, talc and glass. It not only exhibits strong adhesive properties, but also exhibits strong adhesive properties even at relatively low temperatures close to the melting point or softening point and under short bonding conditions. Furthermore, since it has properties similar to those of polyolefins, it also adheres to polyolefins.

(2) Since there is almost no odor, there are no operational problems when manufacturing molded products using the composition of the present invention, and there is no discomfort when using the molded products, and it can also be used as a food packaging material. suitable.

(3) Also, since the color tone is good, it is suitable for applications where the appearance of the product is important.

The reason why the composition of the present invention has strong adhesion, low strength, no odor, and good color tone is currently being elucidated. By adding a hydrotalcite-based compound to the monoolefin, it exerts some effect on the graft-polymerized unsaturated carboxylic acid or its anhydride and the adherend after the adhesion process, resulting in a strong bond. It is also assumed that the unsaturated carboxylic acid or its anhydride remaining unreacted and the hydrotalcite-based compound exert some kind of interaction.

Since the composition of the present invention exhibits the above-mentioned excellent effects, it can be used in a wide variety of fields. Typical uses are shown below.

(1) Composite material of metal plate of the above metal or alloy and sheet or film of boron olefin, such as building materials, automobile parts, furniture, airplane parts, interior materials, etc. (2) Foil of the above metal or alloy and a polyolefin sheet or film, such as food packaging materials, drug packaging materials, etc. Packaging materials, containers, etc. for drugs, etc. (4) ° Coating materials for metal pipes (5) Composite materials of polyolefin and the above-mentioned inorganic materials (6) Composite boards of polyolefin and wood (7)
Composite film of polyolefin and paper (8) Composite materials of polyolefin and wood flour, cellulose fibers, and other various materials can be combined with polyolefin and applied to various fields.

Concave Detailed Description of the Invention (A) Polyolefin The polyolefin used in the present invention includes a homopolymer of ethylene, a homopolymer of propylene, a copolymer of ethylene and propylene, and a copolymer of ethylene and/or propylene having at most the number of carbon atoms. copolymers with 12 other α-olefins (the copolymerization proportion of α-olefins is at most 20% by weight) and copolymers of ethylene with vinyl compounds such as vinyl acetate, acrylic esters and methacrylic esters. Examples include polymers (copolymerization ratio of vinyl compound is at most 50 mol%, preferably at most 40 mol%). The molecular weight of these polyolefins is generally from 1 to 1 million, preferably from 20,000 to 500,000, and particularly preferably from 50,000 to 300,000. In addition, low-density and high-density ethylene homopolymers, propylene homopolymers, copolymers of ethylene and propylene, and copolymers of ethylene or propylene with other α
- Copolymers with olefins are preferred.

(B) Modified polyolefin The modified polyolefin used in the present invention can be obtained by modifying the above-mentioned polyolefin with an unsaturated carboxylic acid or its anhydride.

Representative examples of unsaturated carboxylic acids or their anhydrides include:
Monobasic carboxylic acids having at most 10 carbon atoms and at least one double bond (e.g. acrylic acid, methacrylic acid) and having at most 15 carbon atoms and at least one double bond Diradical carboxylic acids having a bond (e.g. citraconic acid, itaconic acid, maleic acid) and anhydrides of said diradical carboxylic acids (e.g. maleic anhydride, itaconic anhydride, citraconic anhydride, hemic anhydride) can be given. Among these unsaturated carboxylic acids or derivatives thereof, maleic acid and maleic anhydride are preferred.

Modified polyolefins are generally obtained by treating polyolefins with unsaturated carboxylic acids and/or their anhydrides in the presence of organic peroxides, by irradiating electron beams in place of the organic peroxides, and by irradiating ultraviolet rays. Examples include methods of generating radicals in polyolefins using irradiation, heating, inorganic radical initiators, etc., but methods of treating polyolefins with unsaturated carboxylic acids and/or their anhydrides in the presence of organic peroxides include is common.

Among these modification methods, in order to produce the modified polyolefin of the present invention in the presence of an organic peroxide, any of various known methods (for example, solution method, suspension method, melt method) can be used. Can be adopted.

Among these production methods, when producing a modified polyolefin by a solution method, a polyolefin and an unsaturated carboxylic acid and/or its anhydride are added to a nonpolar organic solvent, a radical initiator is added, and the mixture is heated at high temperature. A modified polyolefin can be obtained by heating. In this case, examples of nonpolar organic solvents used include hexane, heptane, benzene, toluene, xylene, chlorobenzene, and tetrachloroethane.

Moreover, as a radical initiator, 2,5-dimethyl-
2,5-di(tert-butylperoxy)hexane, 2.
5-dimethyl-2,5-di(tert-butylperoxy)
Organic peroxides such as hexyne-3 and benzoyl peroxide are mentioned. Furthermore, the treatment temperature is the temperature at which the polyolefin used dissolves, and is generally 1
The temperature is 10 to 160°C, particularly preferably 130 to 150°C.

In addition, when producing a modified polyolefin by a suspension method, a polyolefin and an unsaturated carboxylic acid and/or its anhydride are added to a polar solvent (generally water), and the radical initiator described above is added to the mixture under high pressure. below 100℃
It is obtained by processing at a temperature above.

Furthermore, when producing a modified polyolefin by a melting method, a melt mixing machine (for example, an extruder), which is commonly used in the field of general Kinzo resin, is used to produce a polyolefin, unsaturated carboxylic acid and/or its anhydride. It can also be obtained by processing the above-mentioned radical initiator while melting and kneading it. The kneading temperature at this time varies depending on the type of polyolefin and radical initiator used, but is in the temperature range from above the melting point of the polyolefin used to below 300°C. In the case of polyethylene, it is generally from 120 to 270°C, and in the case of polypropylene, it is - generally from 160 to 270°C.

To produce modified polyolefins using other modification methods, known methods may be applied.

(C) Hydrotalcite compound Furthermore, the hydrotalcite compound used in the present invention has the general formula Mge Me2 (OH)16 q03 ・4H20(
However, Me is AI! It is a hydrated carbonate mineral denoted by +Cr or F., e), and has an orthogonal system and a rhodohedral trigonal lattice.

Common examples include manaseite, stichtite, pyroolite, and Mg. ,,AI,(
oH)tCcos). , 1. - Synthetic hydrotalcites represented by 0.54H,O can also be used.

Furthermore, it is also possible to use a hydrotalcite compound whose surface has been previously treated with stearic acid or the like in order to prevent secondary aggregation of the hydrotalcite compound.

The particle size of the hydrotalcite compound used in the present invention is not particularly limited, but is usually 0.1 to 100 microns, preferably 5 microns or less, particularly 0.5 microns or less.
When the composition of the present invention is produced using a material of micron size or less, it is preferable because a transparent material can be obtained with a hydrotalcite compound content of 20% by weight or less.

Composition (mixing) ratio In producing the composition of the present invention, the mixing ratio of the hydrotalcite compound to 100 parts by weight of modified polyolefin or modified polyolefin and polyolefin is from o, oi to 30 parts by weight, and 0. The amount is preferably 0.02 to 10 parts by weight, particularly preferably 0.05 to 5.0 parts by weight, particularly preferably 0.05 to 1.0 parts by weight. 10
If the mixing ratio of the hydrotalcite compound to 0 parts by weight of the modified polyolefin or the modified polyolefin and the polyolefin is less than 0.01 parts by weight, the above effects cannot be sufficiently exhibited. On the other hand, if it exceeds 30 parts by weight, the polyolefin originally has
``Not only the properties are impaired, but also the adhesion is reduced.

(E) Mixing method In producing the composition of the present invention, the modified polyolefin may be used as it is, but the modified polyolefin and the polyolefin may be used in combination.

In this case, the polyolefin used as the raw material for the modified polyolefin and the polyolefin to be mixed may be the same or different.

Even when using modified polyolefin alone or in combination with modified polyolefin and polyolefin, the amount of unsaturated carboxylic acid and/or its anhydride used for modification (including modified and unreacted) is generally 0.01 to 10% by weight. If the amount of unsaturated luponic acid and/or its anhydride used for modification is less than 0.01% by weight, a composition with sufficient adhesiveness cannot be obtained. On the other hand, if the weight ratio exceeds 10, the above-mentioned properties of the polyolefin will be impaired.

In addition, for the purpose of improving the impact resistance and adhesion of the composition of the present invention, ethylene-α-olefin rubber materials (EPR, E
Rubber-like materials such as PDM) styrene-butadiene copolymer rubber, chlorinated polyethylene and ethylene-vinyl acetate copolymer rubber may also be blended. In this case, modified polyolefin or modified polyolefin and polyolefin 10
The blending ratio of the rubbery material to 0 parts by weight is at most 50 parts by weight.

In preparing the compositions of the present invention, oxygen and heat stabilizers, metal deterioration inhibitors, fillers (e.g. mica, talc, glass, organic fibers, wood flour) commonly used in the field of polyolefins, A lubricant and a flame retardant may also be added. Alternatively, a relatively large amount of filler may be added to the composite material for use as a composite material.

The composition of the invention can also be obtained by mixing all of the composition components simultaneously. You can also pre-mix some of the composition ingredients and air the remaining mixture into the resulting mixture. 5,□6o, -waao. 1/ To produce the composition of the present invention, tri-blending may be carried out using a mixer commonly used in the polyolefin industry such as a Henschel mixer, a Banbury mixer, a Nigoo, a roll mill, and an integrated screw extruder. It can be obtained by melt-kneading using a mixer such as. At this time, the composition obtained by triblending in advance (
A homogeneous composition can be obtained by melt-kneading the mixture).

In this case, the softening point of the modified polyolefin and polyolefin used is generally melt-kneaded, then molded into pellets and subjected to the "long form" described below. It must be carried out at a temperature above 250
If it is carried out at a temperature above .degree. C., the modified polyolefin and a part of the polyolefin may undergo thermal deterioration, so it is a matter of course that it must be carried out at a temperature below this temperature.

The polyolefin composition obtained in this way exhibits strong adhesion to the aforementioned metal materials, polyolefins, polymers with polar groups, and inorganic materials, and the interface can be strongly bonded, making it possible to bond these materials. Manufacture molded products or molded products with these materials, composites,
Laminates can be produced.

To produce composites and laminates, the composition of the present invention or pellets of the composite material may be processed as is by the commonly used extrusion molding methods, injection molding methods, blow molding methods, compression molding methods, inflation methods, and T- A molded product may be manufactured by a molding method such as a film molding method using a method such as a die method, and the resulting molded product may be used to manufacture composites and laminates by the method described below. During manufacturing, the pellets and the other materials may be simultaneously molded (eg, coextruded) and crimped (eg, in the production of electric wires). Furthermore, the molded product produced as described above and other materials may be bonded together. It can also be produced by adhering the powder or pellets of the composition or composite material of the present invention to the surface of another material and press-bonding it.

The crimping method involves crimping using a roll, a press, or the like while heating using a hot roll, an infrared heater, a hot plate, heated air, electromagnetic induction, etc. alone or in combination. It is not necessary to adopt a specific heating method and compression bonding method, and any commonly used method may be used.

When compressing, the heating temperature must be higher than the melting point of the modified polyolein or blend of modified polyolefin and polyolefin used. Generally, the higher the temperature, the better the adhesion, but a high temperature of 280° C. or higher is unsuitable because the hydrotalcite compound will undergo a dehydration reaction. In addition, since the composition of the present invention contains a noidrotalcite-based compound, it is possible to obtain a composite or a laminate having strong adhesive properties even at a relatively low temperature.

EXAMPLES EXAMPLES AND COMPARATIVE EXAMPLES The present invention will be explained in more detail with reference to Examples below.

In addition, in the examples and comparative examples, the melt index (hereinafter referred to as "M, I, J") is JISK-6.
According to 760, the temperature is 190℃ and the load is 2.1
Measurement was performed under the condition of 6kfI. In addition, the melt O flow index (hereinafter referred to as [MFIj)] is based on JIS K-
According to 6758, the temperature is 230°C and the load is 2.
Measurement was performed under the condition of 16 kl. The peel strength was measured by T-peeling a test piece with a width of 15 WI at a speed of 300 cm/min using a tensile tester. Furthermore, the odor is reduced by T-gui film (
Thickness: 80 microns) with heat sealer (ri□, :00
A 20 crn square bag was made by sealing on three sides using a 300° C.), and the odor at the opening of the bag was evaluated as follows.

○: There is some odor, but it is not bad △: Relatively weak odor ×: Strong odor Also, the color tone is T-Gui film (thickness 80 microns,
A paper tube (width: 20 crm, length: toom) was wound around a paper tube, the end surface was observed with the naked eye, and the judgment was made as follows.

○゛: Milky white △: Yellowish white ×: Yellowish brown Furthermore, the transparency was determined by haze (
haze value) was measured.

Example 1 Polypropylene powder (MF I '2.0' El
/10 minutes) 100 parts by weight of maleic anhydride, O6' parts by weight, and 0.4 parts by weight of pendiyl peroxide were uniformly mixed for 5 minutes using a Henschel mixer.

This mixture was supplied to a vented extruder (diameter 401 m), and modified by the melt method in the extruder under graft modification extrusion conditions such that the resin temperature was 220°C and the average residence time (100 seconds). A pellet (hereinafter referred to as "modified PPJ") was produced. The MFI of this modified PP pellet was 30 g/10 minutes.

100 parts by weight of the modified PP pellets and a synthetic hydrotalcite (average particle size 04 microns) having the chemical formula described above.
After pre-triblending 5 parts by weight using a tumbler for 5 minutes, the resulting mixture was supplied to the vented extruder described above and mixed under conditions such that the resin temperature was 220°C and the average residence time was 100 seconds. . The obtained composition and T-
A film having a thickness of 80 microns was formed by the Gouy method. This film was laminated with aluminum foil, and a laminate was produced by heat bonding using a hot plate at a temperature of 180° C. and a pressure of 1 kg/cm 2 for 1 second.

Example 2 Instead of the modified PP pellets used in producing the composition in Example 1, 0.5 parts by weight of water was added to 100 parts by weight of the modified PP pellets, and the mixture was heated in a hot oven at a temperature of 50°C for 4 hours. A composition was produced under the same conditions as in Example 1, except that a treated product obtained by ring-opening treatment of maleic anhydride added during storage for 1 day was used. A film was prepared from the obtained composition in the same manner as in Example 1. The film thus obtained was heat-bonded to aluminum foil under the same conditions as in Example 1 to produce a laminate.

Examples 3 to 5, Comparative Examples 1 to 5 Polypropylene powder (hereinafter referred to as “P”) used in Example 1
P”), high-density polyethylene powder (density 0.9
60 E/Cm, M, ■, 1.0 g/10 min, hereinafter referred to as rHDPEJ) and chain low density polyethylene powder (density 0923 g/Cm, M, I, 1.
0.9/10 min, hereinafter referred to as rL-LDPEj), 100 parts by weight each, unsaturated carboxylic acid or its anhydride (
(the amount of modifier used is shown in Table 1) and in the case of PP (Examples 1.2 and 5 and Comparative Examples 1.4 and 5) 0.4 parts by weight of benzoyl peroxide and H
In the case of DPE and L-LDPE (Examples 2 and 3 and Comparative Examples 2 and 3), 2°5 of 001 parts by weight
-di-methyl-2,5-di(tert-butylperoxy)
Hexane was mixed in advance using a Henschel mixer in the same manner as in Example 1. Each of the obtained mixtures was modified under the same conditions as in Example 1 to produce modified polyolefin pellets.

100 parts by weight of each of the modified polyolefin pellets thus obtained and the synthetic hydrotalcite used in Example 1 as the metal compound, magnesium oxide (average particle size 40 microns) or aluminum hydroxide (gifcy crystals, Tri-blending was carried out in the same manner as in Example 1 using 0.5 parts by weight of each (average particle size: 0.5 microns) (no metal compound was used in Comparative Examples 1 to 3). Each of the mixtures obtained was prepared under the same conditions as in Example 1 using a vented extruder to produce a composition. Using each of the compositions thus obtained, films were produced and laminates were produced in the same manner as in Example 1.

The peel strength and film transparency of each laminate obtained as described above were measured. In addition, the color tone of each film obtained and the odor generated during the production of the laminate were evaluated. The results are shown in Table 2.

Claims (1)

[Scope of Claims] (A) 100 parts by weight of a polyolefin modified with an unsaturated carboxylic acid or an unsaturated carboxylic acid anhydride, or the modified polyolefin and a polyolefin, and (B) 0.01 to 0.01 parts by weight of a hydrotalcite compound. 3
A polyolefin composition consisting of 0 parts by weight.