JP2005220305A - Modified diene base polymer and rubber composition comprising the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a bisphenyl fluorene modified conjugative diene base polymer which, as a rubber material having a high loss modulus, is obtained by introducing a bisphenyl fluorene skeleton into a conjugative diene base polymer. <P>SOLUTION: The modified conjugative diene base polymer has intramolecularly the bisphenyl fluorene skeleton and is preferably obtained by reacting the growing terminal anion of a conjugative diene polymer prepared by anionic polymerization with a bisphenyl fluorene compound having a substitution group reactive with the growing terminal anion. The rubber composition comprises the modified conjugative diene base polymer. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a conjugated diene polymer having a bisphenylfluorene skeleton in the molecule and a rubber composition having a high loss elastic modulus containing the polymer.

  A fluorene ring and two benzene rings crossed in three directions (bisphenylfluorene skeleton).

Polymers having the above are already known and used in fields such as optical materials and electronic materials. Moreover, it is applied to a polymer having resistance in a low temperature region. For example, Patent Document 1 discloses a polyester having the above structure (bisphenylfluorene skeleton), and Non-Patent Document 1 reports a polyester and polyurethane having the above structure (bisphenylfluorene skeleton). ing.

  A rubber material having a high loss elastic modulus has a possibility of being a tread having a high grip property in a tire and a good vibration damping material in other fields. The performance of such materials largely depends on the compounding technique, and a method for improving the loss elastic modulus by modifying the polymer itself as the base of the rubber material has hardly been performed.

JP 2000-344878 A Polymer 51, 872 (2002)

  Accordingly, the present invention provides a bisphenylfluorene-modified conjugated diene polymer in which the bisphenylfluorene skeleton is introduced into a conjugated diene polymer as a rubber material having a high loss elastic modulus, and a rubber composition containing the same. .

  According to the present invention, a modified conjugated diene polymer having a bisphenylfluorene skeleton in the molecule and a rubber composition containing the modified conjugated diene polymer are provided.

  The rubber composition containing the modified conjugated diene polymer introduced with a bisphenylenefluorene skeleton according to the present invention has a high loss elastic modulus.

A polymer with a cardo structure in which a fluorene ring and two benzene rings are perpendicular to each other in three directions is known to exhibit rotational constraints on the main chain and conformation restrictions on the main and side chains due to its special structure. It has been. Based on this, the present inventors considered that a polymer having such a cardo structure may exhibit a unique viscoelastic behavior, and synthesized a modified conjugated diene polymer having the above structure in the molecule, and its physical properties. As a result, it was found that the rubber composition shows a high loss elastic modulus.
The modified conjugated diene polymer having a bisphenylfluorene skeleton in the molecule according to the present invention generates a conjugated diene polymer (for example, SBR, BR, IR, SIR, SBIR, BIR) by anionic polymerization, for example. Bisphenyl having a growing terminal anion and a substituent reactive therewith (for example, oxirane group, thiirane group, isocyanate group, isothiocyanate group, carbonyl group, imino group, vinyl group, sulfate group, phosphate group, halogen, etc.) A modified conjugated diene polymer having a bisphenylfluorene skeleton in the molecule can be obtained by reacting the fluorene compound. The reaction method is not particularly limited. For example, an anionic polymerization of a monomer system containing a diene monomer in an autoclave, for example, in a solvent in the presence of a catalyst (eg, n-butyllithium, s-butyllithium, t-butyllithium). A desired modified diene polymer can be obtained by adding a reactive substituent such as bisphenoxyethanol diglycidyl ether, biscresol fluorenediglycidyl ether, or bisphenol fluorenediglycidyl ether to the reaction. . The molecular weight of the resulting modified diene polymer is not particularly limited, but is preferably a weight average molecular weight of 10,000 to 2,000,000.

  The rubber composition according to the present invention includes a rubber component containing 50 to 100% by weight, preferably 70 to 100% by weight of the modified diene polymer in the rubber component. Examples of other rubber components blended in the rubber composition according to the present invention include any diene rubber or rubber other than diene rubber conventionally used in rubber compositions. Such representative diene rubbers include natural rubber (NR), polyisoprene rubber (IR), various polybutadiene rubbers, various styrene-butadiene copolymer rubbers (SBR), and ethylene-propylene-diene terpolymer rubbers. (EPDM), chloroprene rubber, butyl rubber, halogenated butyl rubber, acrylonitrile-butadiene copolymer rubber, and the like. Examples of non-diene rubbers include ethylene-propylene copolymer rubber, ethylene-butene copolymer rubber, brominated isobutylene-paramethylstyrene copolymer rubber, epichlorohydrin rubber, and silicon rubber. . If the amount of the modified rubber is too small, the desired performance is not exhibited, which is not preferable.

  The rubber composition according to the present invention further contains a reinforcing filler, particularly silica, or silica and carbon black, preferably 5 to 100 parts by weight, more preferably 10 to 90 parts by weight, per 100 parts by weight of the rubber component. Can be blended. If the blending amount is too small, the modification effect is not exhibited and the desired effect cannot be obtained, which is not preferable. On the contrary, if the amount is too large, the reinforcing filler interaction cancels the modification effect.

  The silica used in the present invention may be any silica that can be used for tires, for example, natural silica, synthetic silica, more specifically dry silica or wet silica. Carbon black can be any carbon black that can be used as a rubber reinforcing agent for tires. When carbon black is blended, it can be replaced with silica in an amount of 50% by weight or less of the blending amount of the silica.

  In addition to the essential components described above, the rubber composition according to the present invention is used for tires such as vulcanization or crosslinking agents, vulcanization or crosslinking accelerators, various oils, antioxidants, plasticizers, and other general rubbers. Various additives that are generally blended can be blended, and such additives can be kneaded and vulcanized by a general method to obtain a composition, which can be used for vulcanization or crosslinking. As long as the amount of these additives is not contrary to the object of the present invention, a conventional general amount can be used.

EXAMPLES Hereinafter, although an Example demonstrates this invention further, it cannot be overemphasized that the scope of the present invention is not limited to these Examples.
First, a modified conjugated diene polymer having a bisphenylenefluorene skeleton in the molecule was synthesized. The reagents used for this synthesis are as follows.
Cyclohexane and styrene were manufactured by Kanto Chemical Co., Ltd., dehydrated with molecular sieves 4A, and used after nitrogen publishing.
-Butadiene used was a 99.3% purity product manufactured by Nippon Petrochemical Co., Ltd., dehydrated with Molecular Sieves 4A.
-The n-butyllithium used was a 1.6 mol / L n-hexane solution manufactured by Kanto Chemical Co., Inc.
N, N, N ′, N′-tetramethylethylenediamine (TMEDA) was dehydrated with molecular sieves 4A and used after nitrogen publishing.
-Bisphenoxyethanol full orange glycidyl ether and bisphenol A diglycidyl ether were used after drying under reduced pressure at 100 ° C.
-Toluene manufactured by Kanto Chemical Co., Inc. was refluxed for about one week in the presence of sodium, and after confirming the dark blue color of benzophenone ketyl, which is an indicator of dehydration, distilled.

Example 1
Into an autoclave reactor with an internal volume of 10 liters purged with nitrogen, 3139 g of cyclohexane, 114.4 g (1.100 mol) of styrene, 438.9 g (8.114 mol) of butadiene and 1.103 mL (7.403 mmol) of TMEDA were charged and stirred. Started. After the temperature of the contents in the reaction vessel was 50 ° C., 3.720 mL (5.802 mmol) of n-butyllithium was added. After the polymerization conversion reached 100%, 4.699 g (1.220 mmol) of a 14.3% by weight toluene solution of bisphenoxyethanol diglycidyl ether was added and stirred for 1.5 hours. Subsequently, 0.5 mL of methanol was added and stirred for 30 minutes. A small amount of an anti-aging agent (Irganox 1520 manufactured by Ciba Specialty Chemicals Co., Ltd.) was added to the polymer solution taken out and concentrated under reduced pressure to remove the solvent. The polymer was coagulated and washed in methanol, and then dried to obtain a solid polymer.

Comparative Example 1
Into an autoclave reactor with an internal volume of 10 liters purged with nitrogen, 3138 g of cyclohexane, 115.6 g (1.110 mol) of styrene, 438.9 g (8.172 mol) of butadiene and 1.102 mL (7.398 mmol) of TMEDA were charged and stirred. Started. After the temperature of the contents in the reaction vessel was 50 ° C., 3.805 mL (5.936 mmol) of n-butyllithium was added. After the polymerization conversion reached 100%, 2.993 g (1.372 mmol) of a 15.6 wt% toluene solution of bisphenol A diglycidyl ether was added and stirred for 1.5 hours. Subsequently, 0.5 mL of methanol was added and stirred for 30 minutes. A small amount of an anti-aging agent (Irganox 1520) was added to the removed polymer solution, and the solvent was removed by concentration under reduced pressure. The polymer was solidified and washed in methanol, and then dried to obtain a solid polymer.

Comparative Examples 2 and 3
An autoclave reactor with an internal volume of 10 liters purged with nitrogen was charged with 3138 g of cyclohexane, 115.6 g (1.110 mol) of styrene, 460.8 g (8.172 mol) of butadiene and 0.727 mL (4.880 mmol) of TMEDA and stirred. Started. After the temperature of the contents in the reaction vessel was 50 ° C., 3.270 mL (5.101 mmol) of n-butyllithium was added. After the polymerization conversion rate reached 100%, 0.5 mL of methanol was added and stirred for 30 minutes. A small amount of an anti-aging agent (Irganox 1520) was added to the removed polymer solution, and the solvent was removed by concentration under reduced pressure. The polymer was solidified and washed in methanol, and then dried to obtain a solid polymer (Comparative Example 2). In Comparative Example 3, the amount of n-butyl lithium added was varied and synthesized in the same manner.

  The weight average molecular weight (Mw) and microstructure of the modified SBR obtained in Example 1 and Comparative Examples 1 to 3 are shown in Table I.

Example 2 and Comparative Examples 4-7
In the formulation (parts by weight) shown in Table II, the components other than the vulcanization accelerator and sulfur were kneaded for 3 to 5 minutes with a 0.6 liter hermetic mixer. The obtained master batch, vulcanization accelerator, and sulfur were kneaded with an 8-inch open roll to obtain a rubber composition. This composition was press vulcanized at 160 ° C. for 20 minutes in a 15 × 15 × 0.2 cm mold to obtain a rubber sheet.

The loss elastic modulus G ″ (Pa) of the obtained rubber sheet was measured as follows. The results are shown in Table II, and FIG. 1 shows the loss elastic modulus in terms of strain dispersion.
From FIG. 1, it is clear that the rubber composition containing the modified polymer exhibits a high loss elastic modulus.

Table I Footnote 1) NS-116, Nippon Zeon Co., Ltd. (Mw = 360,000)
2) Synthetic product of Comparative Example 1 (Mw = 398,000)
3) Synthetic product of Comparative Example 2 (Mw = 410,000)
4) Synthetic product of Comparative Example 3 (Mw = 352,000)
5) Synthetic product of Example 1 (Mw = 390,000)
6) Rhodia Co., Ltd. 7) Zinc Hana No. 3, manufactured by Shodo Chemical Co., Ltd. 8) Beads stearic acid Tung, Nippon Oil & Fats Co., Ltd. 9) Bis (3- (trimethoxysilyl) -propyl) tetrasulfide ,
Made by Nippon Unicar Co., Ltd.
10) Made by Nippon Pigment
11) Santoflex 13,6C, manufactured by Nihon Monsanto Co., Ltd.
12) Noxeller CZ-Q, manufactured by Ouchi Shinsei Chemical Co., Ltd.
13) Sunseller DG, manufactured by Sanshin Chemical Co., Ltd.
14) Powdered sulfur, manufactured by Karuizawa Seiren Co., Ltd.

  As described above, a modified conjugated diene polymer in which a bisphenylfluorene skeleton is introduced into a molecule according to the present invention exhibits a high loss elastic modulus when blended in a rubber composition, and is therefore used as a tire tread or a vibration damping material. be able to.

It is a graph which shows distortion (%) dispersion | distribution of the loss elastic modulus G '' (Pa) of the rubber composition of Example 2 and Comparative Examples 4-7.

Claims (5)

  A modified conjugated diene polymer having a bisphenylfluorene skeleton in the molecule.   The modified conjugated diene according to claim 1, obtained by reacting a growing terminal anion of a conjugated diene polymer obtained by anionic polymerization with a bisphenylfluorene compound having a substituent reactive with the growing terminal anion. Polymer.   A rubber composition comprising a rubber component containing 50 to 100% by weight of a modified conjugated diene polymer having a bisphenylfluorene skeleton in the molecule.   The rubber composition according to claim 3, further comprising 5 to 100 parts by weight of a reinforcing filler with respect to 100 parts by weight of the rubber component.   The rubber composition according to claim 4, wherein the reinforcing filler is silica.

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