JP2003221473A - Rubber composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a rubber composition consisting of a rubber clay nanocomposite in which a layer sheet of a mineral treated with an organic compound is dispersed finely and uniformly in a rubber. <P>SOLUTION: The composition is prepared by blending a compound having a maleic anhydride group with a layered clay mineral treated by binding a 6C or higher primary ammonium ion and/or a secondary ammonium ion with the solid rubber through an ionic bond. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rubber composition containing an organically modified layered clay mineral, and more specifically, a layered clay mineral and a maleic anhydride group-containing compound treated with a specific organic modification agent. And a rubber composition in which a layered sheet of a layered clay mineral that has been subjected to an organic treatment is uniformly finely dispersed.

[0002]

2. Description of the Related Art A rubber composition in which a layered sheet of layered clay mineral is dispersed in rubber (Japanese Patent Publication No. 6-84456).
It is also reported that the gas barrier property of such a rubber composition is improved (Japanese Patent Publication No. 8-510421).
It has also been reported that the organized clay and rubber are kneaded with a process oil for rubber to uniformly disperse the clay in the rubber (JP-A-10-8178).
5).

[0003]

SUMMARY OF THE INVENTION It is an object of the present invention to obtain a rubber composition comprising a rubber / clay nanocomposite in which a layered sheet of an organically treated layered clay mineral is uniformly finely dispersed in rubber. And

[0004]

According to the present invention, a layered clay organically treated by ionic bonding of a primary ammonium ion and / or a secondary ammonium ion having 6 or more carbon atoms to a solid rubber. A rubber composition containing a mineral and a compound containing a maleic anhydride group is provided.

Further, according to the present invention, there is provided the rubber composition, wherein maleic anhydride is used as the maleic anhydride group-containing compound, or a maleated liquid rubber having a molecular weight of 30,000 or less is further used.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION Clay minerals organically treated with distearyldimethylammonium ion and stearylammonium ion take in the process oil added during rubber mixing and further swell and expand between the layers of the clay mineral. Easier to disperse into. However, it has been difficult to form a rubber / clay nanocomposite in which a layered sheet of clay mineral is finely dispersed only by hydrophobizing and swelling with these organic treating agents and process oils. Therefore, in the present invention, by adding a maleic anhydride group-containing compound capable of chemically bonding and / or interacting with both a specific ammonium compound which is an organizing agent and rubber which is a matrix, it is possible to obtain a clay mineral during kneading. It is possible to bond and / or interact with a rubber via a maleic anhydride group-containing compound, thereby making it possible to uniformly finely disperse the clay mineral in the rubber.

In the organically treated layered clay mineral used in the present invention, a primary ammonium ion and / or a secondary ammonium ion having 6 or more carbon atoms is ionically bonded to the surface of the layered sheet constituting the clay mineral. A layered clay mineral organized by is used. As the organic treating agent, primary and secondary ammonium ions are used because the maleic anhydride group has higher reactivity. Quaternary ammonium ions are not preferable because the scorch in the rubber composition deteriorates.

Examples of the primary ammonium compound effectively used in the present invention as a treating agent include hexyl ammonium ion, octyl ammonium ion, 2-ethylhexyl ammonium ion, dodecyl ammonium ion, lauryl ammonium ion, octadecyl ammonium ion, stearyl. Ammonium ions, oleyl ammonium ions, etc. are included, and the secondary ammonium compounds include dibutyl ammonium ions, dihexyl ammonium ions, dioctyl ammonium ions, didecyl ammonium ions, didodecyl ammonium ions, distearyl ammonium ions, etc. . Moreover, you may use the monoammonium ion of the diamino compound which has a primary amino group and a secondary amino group in a molecule | numerator. For example, monoammonium ion of stearyl propylene diamine and oleyl propylene diamine can be illustrated.

Examples of the layered clay mineral used in the present invention include smectites such as montmorillonite, saponite, hydelite, nontorite, hectorite, and stevensite, vermiculite, halloysite, and the like, and either natural or synthetic is used. be able to. Also,
In the present invention, one or more of these layered clay minerals may be used.

The maleic anhydride group-containing compound effectively used in the present invention includes maleic anhydride and various maleated liquid rubbers. Particularly, maleated liquid rubber having a molecular weight of 30,000 or less is preferably used. As the maleated liquid rubber, liquid maleic anhydride modified polybutyl rubber, liquid maleic anhydride modified polyisoprene rubber, liquid maleic anhydride modified polybutadiene rubber, and liquid maleic anhydride modified ethylene propylene diene monomer rubber are preferably used.

The solid rubber used in the present invention includes natural rubber, synthetic rubber, thermoplastic elastomer or a mixture thereof. Examples of the synthetic rubber include isoprene rubber, chloroprene rubber, styrene rubber, nitrile rubber, ethylene propylene diene monomer (EPDM) rubber, butadiene rubber, butyl rubber, epichlorohydrin rubber, acrylic rubber, urethane rubber, fluorine rubber, silicone rubber, styrene- Butadiene copolymer rubber, ethylene-vinyl acetate rubber, chlorinated polyethylene, etc. are used, and examples of the thermoplastic elastomer include 1,2-
Polybutadiene, styrene-butadiene block copolymer, styrene-isoprene block copolymer and the like are used. Since this solid rubber is a vulcanized rubber in a bulk state, it is preferable to use one having a molecular weight of 10,000 or more.

The rubber composition of the present invention is obtained by using a general Banbury mixer, a Brabender mixer, a twin-screw extruder or the like into a solid rubber, and a primary ammonium ion and / or a secondary ammonium having 6 or more carbon atoms. By mixing and kneading a layered clay mineral and a maleic anhydride group-containing compound that are organically formed by ionic bonding of ions, or a primary ammonium ion and / or secondary ammonium ion having 6 or more carbon atoms is previously ionized. A rubber in which a layered sheet of the organically modified layered clay mineral is finely dispersed by blending and kneading a reaction product obtained by reacting a layered clay mineral organized by binding with a maleic anhydride group-containing compound. A rubber composition comprising a clay / clay nanocomposite can be obtained. Te, the organic lamellar clay mineral 0.
5 to 70 parts by weight, preferably 1 to 50 parts by weight, and 0.1 to 70 parts by weight, preferably 1 to 50 parts by weight of a maleic anhydride group-containing compound are used.

In addition to the above essential components, the rubber composition of the present invention further comprises a reinforcing agent such as carbon black or silica,
Vulcanizing or crosslinking agents, vulcanization or crosslinking accelerators, various oils, antioxidants, fillers, softeners, various compounding agents and additives to be added to general rubber compositions such as plasticizers may be added. The compounding amount of these compounding agents and additives can also be made into the general amount suitable for the use.

[0014]

EXAMPLES The present invention will be further described below with reference to Examples and Comparative Examples, but it goes without saying that the scope of the present invention is not limited to these Examples.

Organized lamellar clay mineral (organized clay
Preparation of Ray 1) Distearylamine (Pharmine D86 manufactured by Kao Corporation) 5
8 g and 12.4 g of hydrochloric acid were reacted in an isopropanol solution to obtain distearylamine hydrochloride. 95 g of the obtained distearylamine hydrochloride in isopropanol was added to 100 g of a layered clay mineral Na-type montmorillonite (Kunipine F, manufactured by Kunimine Industries Co., Ltd.) previously dispersed in 3 L of water.
Added at ° C. The layered clay mineral was organized by stirring at 95 ° C for 12 hours. The obtained precipitate was filtered, washed with water, and then dried to obtain a clay mineral organically treated with distearyl ammonium ion.

Organized clay minerals (organized clay
Preparation of Ray 2) 38.7 g of stearyl propylene diamine (Pharmine R86, manufactured by Kao Corporation) was reacted with 12.4 g of hydrochloric acid in an isopropanol solution to obtain stearyl propylene diamine hydrochloride. The obtained isopropanol solution of stearyl propylene diamine hydrochloride was added at 95 ° C. to 100 g of the layered clay mineral Na-type montmorillonite (Kunipia F, manufactured by Kunimine Industries Co., Ltd.) previously dispersed in 3 L of water. 95
The layered clay mineral was organized by stirring at 12 ° C for 12 hours. The obtained precipitate was filtered, washed with water, and then dried to obtain a clay mineral organically treated with a corresponding ammonium ion.

Organized clay minerals (organized clay minerals
Preparation of Ray 3) Organized clay 1 (20 g) was reacted with maleic anhydride (0.75 g) in a toluene solution, and then toluene was removed by filtration to obtain Organized clay 3.

Organized lamellar clay mineral (organized clay mineral
Preparation of Ray 4) Organized clay 4 (20 g) was reacted with maleic anhydride (0.86 g) in a toluene solution, and toluene was then distilled off to obtain Organized clay 4.

Examples 1 to 6 and Comparative Examples 1 and 2 The rubber and each compounding agent were loaded into a Banbury mixer at a compounding ratio shown in Table 1 below and sufficiently kneaded to obtain a rubber sheet sample. The dispersibility of the layered clay mineral in the rubber sheet was confirmed by analyzing the sample of the obtained rubber sheet using an X-ray diffraction method. The case where the peak derived from the layered clay mineral disappeared by X-ray diffraction was evaluated as ◯, and the case where the peak derived from the layered clay mineral did not completely disappear and remained was evaluated as Δ.

[0020]

[Table 1]

[0021]

From the results shown in Table 1 above, in the rubber compositions of the examples of the present invention, a rubber composition comprising a rubber / clay nanocomposite in which a layered sheet of an organically modified layered clay mineral was finely dispersed was obtained. You can see that it is being done. On the other hand, it is shown that the rubber composition of Comparative Example in which the organized layered clay mineral is dispersed using the conventional oil has poor dispersibility.

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Naoya Amino             2-1, Oiwake, Hiratsuka-shi, Kanagawa Yokohama Rubber Co., Ltd.             Ceremony Company Hiratsuka Factory F-term (reference) 4J002 AC011 AC021 AC061 AC071                       AC081 AC091 AC112 BB061                       BB151 BB181 BB212 BB241                       BD141 BG041 BP011 CH041                       CK051 CP031 DG046 DJ006                       DJ046 EL147 FB086 FD01

Claims (4)

[Claims] 1. A layered clay mineral and a maleic anhydride group-containing compound, which are organically treated by ionic bonding of a primary ammonium ion and / or a secondary ammonium ion having 6 or more carbon atoms to a solid rubber. Compounded rubber composition. 2. The rubber composition according to claim 1, wherein the compound containing a maleic anhydride group is maleic anhydride. 3. The maleic anhydride group-containing compound has a molecular weight of 3.
The rubber composition according to claim 1, which is a maleinized liquid rubber of 0000 or less. 4. The maleated liquid rubber is liquid maleic anhydride modified polybutyl rubber, liquid maleic anhydride modified polyisoprene rubber, liquid maleic anhydride modified polybutadiene rubber, liquid maleic anhydride modified ethylene propylene diene monomer rubber. The rubber composition according to item 3.