Method for producing modified conjugated diene polymer, polymer composition, crosslinked polymer and tire

Abstract

A modified conjugated diene polymer obtained by modifying a conjugated diene polymer that is obtained by polymerizing a conjugated diene compound or polymerizing a conjugated diene compound and an aromatic vinyl compound is produced by a production method comprising a first modification step wherein an unsaturated binding site at least either in the skeleton or at the side chain of the conjugated diene polymer is reacted with a first compound having a group 4 or 13 element of the periodic table.

Claims

1. A method for modifying a conjugated diene polymer obtained by polymerizing a conjugated diene compound or polymerizing a conjugated diene compound and an aromatic vinyl compound, the method comprising: reacting an active end of the conjugated diene polymer with a third compound having a functional group that interacts with silica; subsequently reacting an unsaturated binding site in at least one of a skeleton and a side chain of the conjugated diene polymer with a first compound having a boron-hydrogen bond; and subsequently reacting the conjugated diene polymer with a second compound having a functional group that interacts with silica, the functional group comprising at least one nitrogen atom; wherein the conjugated diene polymer is a polymer obtained by polymerization in the presence of an alkali metal compound or an alkaline earth metal compound.

2. The method for producing a modified conjugated diene polymer according to claim 1, wherein the third compound is at least one selected from the group consisting of: (I) a compound (a-1) represented by the following formula (1): ##STR00002## wherein: A.sup.1 is a monovalent functional group which has at least one atom selected from the group consisting of a nitrogen atom, a phosphorus atom, and a sulfur atom, does not have an active hydrogen, and binds to R.sup.3 with the nitrogen atom, the phosphorus atom, or the sulfur atom; R.sup.1 and R.sup.2 are each a hydrocarbyl group; R.sup.3 is a hydrocarbylene group; and n is an integer of 0 to 2; provided that, when plural R.sup.1 and R.sup.2 groups are present, the groups R.sup.1 and R.sup.2 may each be the same or different; (II) a compound (a-2) having, in the molecule, at least one functional group (x1) selected from the group consisting of a cyclic ether group and a (thio)carbonyl group and a group (x2) different from the functional group (x1), which has at least one atom selected from the group consisting of a nitrogen atom, a phosphorus atom, an oxygen atom, and a sulfur atom and does not have an active hydrogen; and (III) a compound (a-3) having two or more iso(thio)cyanate groups in the molecule.

3. A method for preparing a polymer composition comprising: modifying a conjugated diene polymer by the method according to claim 1; and blending the modified conjugated diene polymer with silica and a crosslinking agent.

4. A method for producing a crosslinked polymer, comprising: preparing a polymer composition by the method of claim 3; and cross-linking the polymer composition.

5. A method for producing a tire, comprising: producing a crosslinked polymer by the method of claim 4; wherein producing the crosslinked polymer comprises molding the polymer composition and crosslinking to form a tread or a side wall of the tire.

Description

EXAMPLES

(1) The present invention will be specifically described below on the basis of Examples but the invention is not construed as being limited to these Examples. Incidentally, parts and % in Examples and Comparative Examples are by mass basis unless otherwise specified. Measuring methods of various physical property values of the modified conjugated diene polymers are as follows. Bound styrene content [%]: it was determined by .sup.1H-NMR of 500 MHz. Vinyl content [%]: it was determined by .sup.1H-NMR of 500 MHz before modification. Weight-average molecular weight before modification: it was determined in terms of polystyrene from the retention time corresponding to the maximum peak height of a GPC curve obtained using gel permeation chromatography (trade name HLC-8120GPC manufactured by Tosoh Corporation).
Column: trade name GMHXL (manufactured by Tosoh Corporation), 2 columns
Column temperature: 40 C.
Mobile phase: tetrahydrofuran
Flow rate: 1.0 ml/minute
Sample concentration: 10 mg/20 ml

Example 1A

Synthesis of Modified Conjugated Diene Polymer A1

(2) In an autoclave reactor having an internal volume of 5 liters in which the atmosphere was replaced with nitrogen, 2,500 g of cyclohexane as a solvent, 2.45 mmol of 2,2-di(2-tetrahydrofuryl)propane (compound A) as a vinyl content adjuster, 125 g of styrene and 365 g of 1,3-butadiene as monomers were charged. After adjusting the temperature of contents in the reactor to 10 C., 5.20 mmol of n-butyllithium was added as a polymerization initiator thereto to initiate polymerization. The polymerization was conducted under adiabatic conditions, and the maximum temperature reached 85 C. At the time when the polymerization conversion reached 99% (after an elapse of time of 22 minutes from the initiation of the polymerization), 10 g of 1,3-butadiene was further added over a period of 2 minutes, and the polymerization was further conducted for 3 minutes. Then, 5.20 mmol of isopropanol as a polymerization terminator was added thereto to terminate the reaction. Thereafter, 13.4 mmol of pinacolborane (compound F) was added as a first compound (modifying agent 1) thereto, and a reaction was performed for 15 minutes.

(3) To the resulting polymer solution, 2.0 g of 2,6-di-tert-butyl-p-cresol was added. Then, solvent removal was conducted by performing steam striping with using hot water adjusted to pH 9 with sodium hydroxide, thereby obtaining a modified conjugated diene polymer. Thereafter, the resulting polymer was dried by means of a hot roll adjusted to a temperature of 110 C. to obtain a modified conjugated diene polymer A1.

Examples 2A to 5A

Synthesis of Modified Conjugated Diene Polymers A2 to A5

(4) Modified conjugated diene polymers A2 to A5 were obtained in the same manner as in Example 1A with the exception that, as the first compound to be used, the compound F was changed to the compounds G to J as shown in the following Table 1.

Example 6A

Synthesis of Modified Conjugated Diene Polymer A6

(5) A modified conjugated diene polymer A6 was obtained in the same manner as in Example 1A with the exception that 4.20 mmol of piperidine was further charged into the autoclave reactor before the initiation of polymerization.

Example 7A

Synthesis of Modified Conjugated Diene Polymer A7

(6) A polymerization reaction was performed in the same manner as in the above Example 1A, and then 5.20 mmol of isopropanol as a polymerization terminator was added to terminate the reaction. Thereafter, 13.4 mmol of the compound F was added as a first compound thereto, and a reaction was performed for 15 minutes. Then, to the resulting polymer solution, 13.4 mmol of N-[2-[3-(trimethoxysilyl)propylamino]ethyl]ethylenediamine (compound K) was added as a second compound (modifying agent 2) thereto, and a reaction was performed for 15 minutes.

(7) To the resulting polymer solution, 2.0 g of 2,6-di-tert-butyl-p-cresol was added. Then, solvent removal was conducted by performing steam striping with using hot water adjusted to pH 9 with sodium hydroxide, thereby obtaining a modified conjugated diene polymer. Thereafter, the resulting polymer was dried by means of a hot roll adjusted to a temperature of 110 C. to obtain a modified conjugated diene polymer A7.

Example 8A

Synthesis of Modified Conjugated Diene Polymer A8

(8) A modified conjugated diene polymer A8 was obtained in the same manner as in Example 7A with the exception that the amounts of the compound F and the compound K to be used were changed as described in the following Table 1.

Example 9A

Synthesis of Modified Conjugated Diene Polymer A9

(9) A modified conjugated diene polymer A9 was obtained in the same manner as in Example 7A with the exception that, as a second compound to be used, the compound K was changed to the compound L as shown in the following Table 1.

Examples 10A and 11A

Synthesis of Modified Conjugated Diene Polymers A10 and A11

(10) Modified conjugated diene polymers A10 and A11 were obtained in the same manner as in Example 7A with the exception that, as second compounds to be used, the compound K was changed to 5.0 g of the compound M or 5.0 g of the compound N as shown in the following Tables 1 and 2.

Example 12A

Synthesis of Modified Conjugated Diene Polymer A12

(11) Polymerization was initiated in the same manner as in the above Example 1A, and after 1,3-butadiene was further added, 4.46 mmol of N,N-bis(trimethylsilyl)aminopropylmethyldiethoxysilane (compound C) was added as an end-modifying agent in stead of isopropanol, and a reaction was performed for 15 minutes. Then, 13.4 mmol of the compound F was added as a first compound thereto, and a reaction was performed for 15 minutes. To the resulting polymer solution, 13.4 mmol of the compound K was added as a second compound thereto, and a reaction was further performed for 15 minutes. To the resulting polymer solution, 2.0 g of 2,6-di-tert-butyl-p-cresol was added. Then, solvent removal was conducted by performing steam striping with using hot water adjusted to pH 9 with sodium hydroxide, thereby obtaining a modified conjugated diene polymer. Thereafter, the resulting polymer was dried by means of a hot roll adjusted to a temperature of 110 C. to obtain a modified conjugated diene polymer A12.

Examples 13A and 14A

Synthesis of Modified Conjugated Diene Polymers A13 and A14

(12) Modified conjugated diene polymers A13 and A14 were obtained in the same manner as in Example 12A with the exception that, as an end-modifying agent to be used, the compound C was changed to the compound D or the compound E as shown in the following Table 2.

Example 15A

Synthesis of Modified Conjugated Diene Polymer A15

(13) A modified conjugated diene polymer A15 was obtained in the same manner as in Example 12A with the exception that, in the above Example 12A, 0.56 mmol of silicon tetrachloride was added as an end-modifying agent and a reaction was performed for 5 minutes, instead of the operation that 4.46 mmol of the compound C was added as an end-modifying agent and a reaction was performed for 15 minutes, and then 2.23 mmol of the compound C was added as an end-modifying agent and a reaction was performed for 15 minutes.

Example 16A

Synthesis of Modified Conjugated Diene Polymer A16

(14) A modified conjugated diene polymers A16 was obtained in the same manner as in Example 12A with the exception that, as a second compound to be used, the compound K was changed to 5.0 g of the compound M as shown in the following Table 2.

Example 17A

Synthesis of Modified Conjugated Diene Polymer A17

(15) A modified conjugated diene polymers A17 was obtained in the same manner as in Example 15A with the exception that, as a second compound to be used, the compound K was changed to 5.0 g of the compound M as shown in the following Table 2.

Example 18A

Synthesis of Modified Conjugated Diene Polymer A18

(16) A modified conjugated diene polymer A18 was obtained in the same manner as in Example 12A with the exception that 4.20 mmol of piperidine was further charged into the autoclave reactor before the initiation of polymerization.

Example 19A

Synthesis of Modified Conjugated Diene Polymer A19

(17) A modified conjugated diene polymer A19 was obtained in the same manner as in Example 18A with the exception that the piperidine to be used was changed to N-(tert-butyldimethylsilyl)piperazine (compound B).

Example 20A

Synthesis of Modified Conjugated Diene Polymer A20

(18) A modified conjugated diene polymers A20 was obtained in the same manner as in Example 18A with the exception that, as a second compound to be used, the compound K was changed to 5.0 g of the compound M as shown in the following Table 2.

Example 21A

Synthesis of Modified Conjugated Diene Polymer A21

(19) A modified conjugated diene polymer A21 was obtained in the same manner as in Example 19A with the exception that, in the above Example 19A, after the second compound was added and a reaction was performed for 15 minutes, 16.8 mmol of silicon tetrachloride was further added as an onium salt-forming agent.

Example 22A

Synthesis of Modified Conjugated Diene Polymer A22

(20) A modified conjugated diene polymers A22 was obtained in the same manner as in Example 20A with the exception that, as an onium salt-forming agent, silicon tetrachloride was changed to 13.6 mmol of maleic acid as shown in the following Table 3.

Comparative Synthetic Example 1

Synthesis of Conjugated Diene Polymer B1

(21) In an autoclave reactor having an internal volume of 5 liters in which the atmosphere was replaced with nitrogen, 2,500 g of cyclohexane as a solvent, 2.45 mmol of the compound A as a vinyl content adjuster, 125 g of styrene and 365 g of 1,3-butadiene as monomers were charged. After adjusting the temperature of contents in the reactor to 10 C., 5.20 mmol of n-butyllithium was added as a polymerization initiator thereto to initiate polymerization. The polymerization was conducted under adiabatic conditions, and the maximum temperature reached 85 C. At the time when the polymerization conversion reached 99% (after an elapse of time of 22 minutes from the initiation of the polymerization), 10 g of 1,3-butadiene was further added over a period of 2 minutes, and the polymerization was further conducted for 3 minutes. Then, 5.20 mmol of isopropanol as a polymerization terminator was added thereto to terminate the reaction.

(22) To the resulting polymer solution, 2.0 g of 2,6-di-tert-butyl-p-cresol was added. Then, solvent removal was conducted by performing steam striping with using hot water adjusted to pH 9 with sodium hydroxide, thereby obtaining a modified conjugated diene polymer. Thereafter, the resulting polymer was dried by means of a hot roll adjusted to a temperature of 110 C. to obtain a conjugated diene polymer B1.

Comparative Synthetic Example 2

Synthesis of Modified Conjugated Diene Polymer B2

(23) A modified conjugated diene polymer B2 was obtained by performing the same operation as in Comparative Synthetic Example 1 with the exception that 4.20 mmol of piperidine was further charged into the autoclave reactor before the initiation of polymerization.

Comparative Example 3

Synthesis of Modified Conjugated Diene Polymer B3

(24) Polymerization was initiated in the same manner as in the above Comparative Synthetic Example 1, and after 1,3-butadiene was further added, 4.46 mmol of the compound C was added as an end-modifying agent in stead of isopropanol, and a reaction was performed for 15 minutes. To the resulting polymer solution, 2.0 g of 2,6-di-tert-butyl-p-cresol was added. Then, solvent removal was conducted by performing steam striping with using hot water adjusted to pH 9 with sodium hydroxide, thereby obtaining a modified conjugated diene polymer. Thereafter, the resulting polymer was dried by means of a hot roll adjusted to a temperature of 110 C. to obtain a modified conjugated diene polymer B3.

Comparative Synthetic Example 4

Synthesis of Modified Conjugated Diene Polymer B4

(25) A modified conjugated diene polymer B4 was obtained in the same manner as in Comparative Synthetic Example 3 with the exception that, in the above Comparative Synthetic Example 3, 0.56 mmol of silicon tetrachloride was added as an end-modifying agent and a reaction was performed for 5 minutes, instead of the operation that 4.46 mmol of the compound C was added as an end-modifying agent and a reaction was performed for 15 minutes, and then 2.23 mmol of the compound C was added as an end-modifying agent and a reaction was performed for 15 minutes.

Comparative Synthetic Example 5

Synthesis of Modified Conjugated Diene Polymer B5

(26) A modified conjugated diene polymer B5 was obtained in the same manner as in Comparative Synthetic Example 3 with the exception that 4.20 mmol of piperidine was further charged into the autoclave reactor before the initiation of polymerization.

(27) The above polymerization formulas are shown in Tables 1 to 3 together with the measurement results of various physical property values of the resulting polymers.

(28) TABLE-US-00001 TABLE 1 Exam- Exam- Exam- Exam- Exam- Exam- Exam- Exam- Exam- Exam- ple 1A ple 2A ple 3A ple 4A ple 5A ple 6A ple 7A ple 8A ple 9A ple 10A Kind of (modified) conjugated diene polymer A1 A2 A3 A4 A5 A6 A7 A8 A9 A10 Polymer- Solvent ization cyclohexane (g) 2500 2500 2500 2500 2500 2500 2500 2500 2500 2500 formula Vinyl content adjuster compound A (mmol) 2.45 2.45 2.45 2.45 2.45 2.45 2.45 2.45 2.45 2.45 Polymerizing monomer styrene (g) 125 125 125 125 125 125 125 125 125 125 1,3-butadiene (g) 365 365 365 365 365 365 365 365 365 365 further added butadiene (g) 10 10 10 10 10 10 10 10 10 10 Polymerization initiator n-butyllithium (mmol) 5.20 5.20 5.20 5.20 5.20 5.20 5.20 5.20 5.20 5.20 piperidine (mmol) 4.20 compound B (mmol) End-modifying agent compound C (mmol) compound D (mmol) compound E (mmol) silicon tetrachloride (mmol) Modifying agent 1 compound F (mmol) 13.4 13.4 13.4 26.8 13.4 13.4 compound G (mmol) 13.4 compound H (mmol) 13.4 compound I (mmol) 13.4 compound J (mmol) 13.4 Modifying agent 2 compound K (mmol) 13.4 26.8 compound L (mmol) 13.4 compound M (g) 5.0 compound N (g) Onium salt- forming agent silicon tetrachloride (mmol) maleic acid (mmol) Crude Bound styrene content [%] 25 25 25 25 25 25 25 25 25 25 rubber Vinyl content [%] 55 55 55 55 55 56 55 55 55 55 proper- Weight-average [10.sup.4] 20 20 20 20 20 21 20 20 20 20 ties molecular weight before modification Mooney viscosity [10.sup.4] 9 9 10 11 12 13 11 15 12 8 (ML1 + 4, 100 C.)

(29) TABLE-US-00002 TABLE 2 Exam- Exam- Exam- Exam- Exam- Exam- Exam- Exam- Exam- Exam- ple 11A ple 12A ple 13A ple 14A ple 15A ple 16A ple 17A ple 18A ple 19A ple 20A Kind of (modified) conjugated diene polymer A11 A12 A13 A14 A15 A16 A17 A18 A19 A20 Polymer- Solvent ization cyclohexane (g) 2500 2500 2500 2500 2500 2500 2500 2500 2500 2500 formula Vinyl content adjuster compound A (mmol) 2.45 2.45 2.45 2.45 2.45 2.45 2.45 2.45 2.45 2.45 Polymerizing monomer styrene (g) 125 125 125 125 125 125 125 125 125 125 1,3-butadiene (g) 365 365 365 365 365 365 365 365 365 365 further added butadiene (g) 10 10 10 10 10 10 10 10 10 10 Polymerization initiator n-butyllithium (mmol) 5.20 5.20 5.20 5.20 5.20 5.20 5.20 5.20 5.20 5.20 piperidine (mmol) 4.20 4.20 compound B (mmol) 4.20 End-modifying agent compound C (mmol) 4.46 2.23 4.46 2.23 4.46 4.46 4.46 compound D (mmol) 4.46 compound E (mmol) 4.46 silicon tetrachloride (mmol) 0.56 0.56 Modifying agent 1 compound F (mmol) 13.4 13.4 13.4 13.4 13.4 13.4 13.4 13.4 13.4 13.4 compound G (mmol) compound H (mmol) compound I (mmol) compound J (mmol) Modifying agent 2 compound K (mmol) 13.4 13.4 13.4 13.4 13.4 13.4 compound L (mmol) compound M (g) 5.0 5.0 5.0 compound N (g) 5.0 Onium salt- forming agent silicon tetrachloride (mmol) maleic acid (mmol) Crude Bound styrene content [%] 25 25 25 25 25 25 25 25 25 25 rubber Vinyl content [%] 55 55 55 55 55 55 55 55 55 55 proper- Weight-average [10.sup.4] 20 20 20 20 20 20 20 20 21 20 ties molecular weight before modification Mooney viscosity [10.sup.4] 8 12 11 28 55 10 51 12 15 12 (ML1 + 4, 100 C.)

(30) TABLE-US-00003 TABLE 3 Comparative Comparative Comparative Comparative Comparative Exam- Exam- Synthetic Synthetic Synthetic Synthetic Synthetic ple 21A ple 22A Example 1 Example 2 Example 3 Example 4 Example 5 Kind of (modified) conjugated diene polymer A21 A22 B1 B2 B3 B4 B5 Polymer- Solvent ization cyclohexane (g) 2500 2500 2500 2500 2500 2500 2500 formula Vinyl content adjuster compound A (mmol) 2.45 2.45 2.45 2.45 2.45 2.45 2.45 Polymerizing monomer styrene (g) 125 125 125 125 125 125 125 1,3-butadiene (g) 365 365 365 365 365 365 365 further added butadiene (g) 10 10 10 10 10 10 10 Polymerization initiator n-butyllithium (mmol) 5.20 5.20 5.20 5.20 5.20 5.20 5.20 piperidine (mmol) 4.20 4.20 4.20 4.20 compound B (mmol) End-modifying agent compound C (mmol) 4.46 4.46 4.46 2.23 4.46 compound D (mmol) compound E (mmol) silicon tetrachloride (mmol) 0.56 Modifying agent 1 compound F (mmol) 13.4 13.4 compound G (mmol) compound H (mmol) compound I (mmol) compound J (mmol) Modifying agent 2 compound K (mmol) 13.4 compound L (mmol) compound M (g) 5.0 compound N (g) Onium salt- forming agent silicon tetrachloride (mmol) 16.8 maleic acid (mmol) 13.6 Crude Bound styrene content [%] 25 25 25 25 25 25 25 rubber Vinyl content [%] 55 55 55 55 55 55 55 proper- Weight-average [10.sup.4] 20 20 20 20 20 20 20 ties molecular weight before modification Mooney viscosity [10.sup.4] 75 63 5 6 9 53 10 (ML1 + 4, 100 C.)

(31) In Tables 1 to 3, abbreviations of the compounds are as follows. Compound A: 2,2-di(2-tetrafuryl)propane Compound B: N-(tert-butyldimethylsilyl)piperazine Compound C: N,N-bis(tromethylsilyl)aminopropylmethyldiethoxysilane Compound D: S-trimethylsilylmercaptopropyltriethoxysilane Compound E: N,N,N,N-tetraglycidyl-1,3-bisaminomethylcyclohexane Compound F: pinacolborane Compound G: 9-borabicyclo[3.3.1]nonane Compound H: diisopropylaluminum hydride Compound I: bis(cyclopentadienyl)titanium monochloride monohydride Compound J: bis(cyclopentadienyl)zirconium monochloride monohydride Compound K: N-[2-[3-(trimethoxysilyl)propylamino]ethyl]ethylenediamine Compound L: N,N,N,N-tetrakis(2-hydroxypropyl)ethylenediamine Compound M: KF-393 (manufactured by Shin-Etsu Chemical Company, Ltd.) Compound N: MPG-130 (manufactured by Nippon Nyukazai Co., Ltd.)

Production of Polymer Composition and Crosslinked Polymer

Example 1B

(32) Using the above modified conjugated diene polymer A1, a polymer composition was produced by blending individual components according to the blending formula shown in the following Table 4 and kneading them. The kneading was performed by the following method. Using a plastomill (internal volume: 250 ml) equipped with a temperature controller, the modified conjugated diene polymer A, polybutadiene rubber, an extender oil, silica, carbon black, a silane coupling agent, stearic acid, an anti-aging agent, and zinc oxide were blended and kneaded under conditions of a filling rate of 72% and a rotation number of 60 rpm, as first-step kneading. Then, the blended product obtained above was cooled to room temperature, and thereafter kneaded with blending sulfur and a vulcanizing accelerator, as second-step kneading. This was molded, and vulcanized at 160 C. for a predetermined time by means of a vulcanizing press to obtain a crosslinked polymer (vulcanized polymer).

(33) TABLE-US-00004 TABLE 4 Blending formula Parts by mass Modified conjugated diene polymer 70 Polybutadiene rubber *1 30 Extender oil *2 37.5 Silica *3 70 Carbon black *4 5.6 Silane coupling agent *5 5.6 Stearic acid 2 Anti-aging agent *6 1 Zinc oxide 3 Vulcanizing accelerator D *7 1.5 Vulcanizing accelerator CZ *8 1.8 Sulfur 1.5

(34) In Table 4, for individual components, the trade names used are as follows. *1: BR01 manufactured by JSR Corporation, *2: JOMO Process NC-140 manufactured by Japan Energy Corporation, *3: ZEOSIL 1165MP manufactured by Rhodia, *4: Diablack N339 manufactured by Mitsubishi Chemical Corporation, *5: Si 75 manufactured by Evonik Industries AG, *6: OZONONE 6C manufactured by Seiko Chemical Co., Ltd., *7: Nocceler D manufactured by Ouchi Shinko Chemical Industrial Co., Ltd., *8: Nocceler CZ manufactured by Ouchi Shinko Chemical Industrial Co., Ltd.

Examples 2B to 22B, Comparative Examples 1B to 5B

(35) Polymer compositions and crosslinked polymers were obtained in the same manner as in the above Example 1B with the exception that the kind of the modified conjugated diene polymer to be used was changed as shown in the following Tables 5 to 8. In Comparative Example 1B, the unmodified conjugated diene polymer B1 was used instead of the modified conjugated diene polymer A1.

(36) TABLE-US-00005 TABLE 5 Example 1B Example 2B Example 3B Example 4B Example 5B Example 6B Example 7B Kind of polymer A1 A2 A3 A4 A5 A6 A7 Blend Mooney viscosity 48 49 47 47 46 53 52 (ML1 + 4, 100 C.) 0 C. tan (INDEX) 112 111 110 109 108 115 122 70 C. tan (INDEX) 112 110 109 109 109 118 125

(37) TABLE-US-00006 TABLE 6 Comparative Comparative Example 8B Example 9B Example 10B Example 11B Example 1B Example 2B Kind of polymer A8 A9 A10 A11 B1 B2 Blend Mooney viscosity 57 50 40 41 43 49 (ML1 + 4, 100 C.) 0 C. tan (INDEX) 126 118 126 124 100 104 70 C. tan (INDEX) 128 122 117 117 100 105

(38) TABLE-US-00007 TABLE 7 Example 12B Example 13B Example 14B Example 15B Example 16B Example 17B Example 18B Kind of polymer A12 A13 A14 A15 A16 A17 A18 Blend Mooney viscosity 83 87 92 95 60 70 86 (MLI + 4, 100 C.) 0 C. tan (INDEX) 128 124 122 123 126 124 130 70 C. tan (INDEX) 130 125 124 125 120 118 133

(39) TABLE-US-00008 TABLE 8 Comparative Comparative Comparative Example 19B Example 20B Example 21B Example 22B Example 3B Example 4B Example 5B Kind of polymer A19 A20 A21 A22 B3 B4 B5 Blend Mooney viscosity 96 68 86 69 65 78 72 [ML1 + 4, 100 C.) 0 C. tan (INDEX) 136 128 131 130 100 98 104 70 C. tan (INDEX) 138 124 134 133 100 95 105

(40) <Evaluation>

(41) For respective polymer compositions and crosslinked polymers of the above Examples 1B to 22B and Comparative Examples 1B to 5B, evaluation of properties representing tire performance was carried out as shown below. The evaluation results are shown in the above Tables 5 to 8.

(42) (1) Mooney Viscosity (Blend Mooney Viscosity)

(43) The polymer composition before vulcanization was used as a sample for measurement, and the measurement was carried out in accordance with JIS K6300-1 using an L-rotor under conditions of preheating for 1 minute, a rotor operation time of 4 minutes, and a temperature of 100 C. The smaller the numerical value is, the more satisfactory the workability is.

(44) (2) 0 C. Tan

(45) The cross-linked polymer was used as a sample for measurement, and the measurement was carried out under conditions of a shear strain of 0.1%, an angular velocity of 100 radians per second, and 0 C., using ARES-RDA (manufactured by TA instruments Inc.). The measurement results were indicated by indices taking Comparative Example 1B as 100 for Examples 1B to 11B and Comparative Example 2B in which end modification was not performed and taking Comparative Example 3B as 100 for Examples 12B to 22B and Comparative Examples 4B and 5B in which end modification was performed. The larger the numerical value is, the more satisfactory the wet skid resistance is.

(46) (2) 70 C. tan

(47) The crosslinked polymer was used as a sample for measurement, and the measurement was carried out under conditions of a shear strain of 1.0%, an angular velocity of 100 radians per second, and 70 C., using ARES-RDA (manufactured by TA instruments Inc.). The measurement results were indicated by indices taking Comparative Example 1B as 100 for Examples 1B to 11B and Comparative Example 2B in which end modification was not performed and taking Comparative Example 3B as 100 for Examples 12B to 22B and Comparative Examples 4B and 5B in which end modification was performed. The larger the numerical value is, the smaller the energy loss is and the more satisfactory the low hysteresis loss properties are.

(48) As shown in Tables 5 and 6, in Examples 1B to 11B, the low hysteresis loss properties and the wet skid resistance were both satisfactory as compared with Comparative Examples 1B and 2B. Also, as shown in Tables 7 and 8, in Examples 12B to 22B, the low hysteresis loss properties and the wet skid resistance were both satisfactory as compared with Comparative Examples 3B to 5B. Moreover, with regard to those in which the compound M or N was used as a modifying agent (second compound) (Examples 10B, 11B, 16B, 17B, 20B, and 22B), it was found that a sufficiently high effect was exhibited as a compatibilizing agent (wetting agent).