Patent Application
20080097023
Examples will be used to further explain the present invention, but the present invention is by no means limited to these Examples. Note that the “parts” hereinbelow indicate “parts by weight”.
The compounding agents used in the Examples etc. were as follows:
S-SBR: Bayer's solution polymerization SBR VSL5025 (oil extension 37.5 phr)
BR: Nippon Zeon's BR 1220
Filler (carbon black): Tokai Carbon's N234
Filler (silica): Rhodia's Z1165MP
Silane coupling agent: Degussa's bis-[3-(triethoxysilyl)-propyl]tetrasulfide (i.e., Si69)
Zinc white: Seido Chemical (Zinc White No. 3)
Stearic acid: NOF Corporation's Beads Stearic Acid
Antioxidant 6C: Flexsys' N-phenyl-N′-(1,3-dimethylbutyl)-p-phenylenediamine (SANTOFLEX 6PPD)
Process oil: Fuji Kosan's Aromatics 3
Sulfur: Hosoi Chemical Industrial's oil-extended sulfur
Vulcanization accelerator CZ: N-cyclohexyl-2-benzothiazyl sulfenamide (Noccelar CZ-G) made by Ouchi Shinko Chemical Industrial
Vulcanization accelerator DPG: Ouchi Shinko Chemical Industrial diphenyl guanidine (Noccelar D)
Polyether E1: THF14.3 mole/E020.4 mole random adduct of 1,4-butanediol synthesized in the following Synthesis Example 1
A glass autoclave was charged with 90 parts of 1,4-butanediol (1.0 mole), 1032 parts of THF (14.3 moles), and 12.8 parts of BF3-THF and 896 parts of EO (20.4 moles) was dropwise added from a pressure resistant dropping funnel at 35 to 50° C. over 10 hours. Thereafter, the resultant mixture was reacted at 50° C. over 5 hours, followed by cooling. Further, 7.4 parts of a 48% aqueous NaOH solution was added, then the unreacted substance was distilled off at 30 mmHg or less. Thereafter, an adsorption treatment agent (Kyowa Chemical Industry Kyoward 600 and Kyoward 1000, the same below) was used for treatment, then the resultant mixture was filtered, then dehydrated under reduced pressure (i.e., 130° C., 30 mmHg or less, 1 hour, the same below) to obtain 2000 parts of a THF14.3 mole/EO20.4 mole random addition product of 1,4-butanediol (polyether E1).
Polyether E2: THF6.5 mole/PO10.0 mole random addition product of lauryl alcohol synthesized in the following Synthesis Example 2
A glass autoclave was charged with 186 parts of lauryl alcohol (1.0 mole), 468 parts of tetrahydrofuran (THF) (6.5 moles) and 7.9 parts of BF3-THF and 580 parts (10.0 moles) of PO was dropwise added from a pressure resistant dropping funnel at 35 to 50° C. over 10 hours. Thereafter, the resultant mixture was reacted at 50° C. over 5 hours, followed by cooling. Further, 4.8 parts of a 48% aqueous NaOH solution was added, then an adsorption treatment agent was used for treatment, and the resultant mixture was filtered and dehydrated under a reduced vacuum at 130° C. and 30 mmHg or less to obtain 1230 parts of a THF6.5 mole/PO10.0 mole random addition product of lauryl alcohol (polyether E2).
Polyether E3: Ester obtained from the polyether E2 synthesized in the following Synthesis Example 3 and succinic acid
1234 parts of the (polyether E2) obtained in the Synthesis Example 2 (1.0 mole), 59 parts of succinic acid (0.5 mole), 4.8 parts of paratoluene sulfonic acid 1-hydrate and 3.2 parts of hypophosphoric acid were charged and reacted (esterified) over 12 hours at 100 to 120° C., while passing nitrogen through the solution and removing the water generated in the reaction. The resultant mixture was treated with an adsorption treatment agent and filtered to remove the paratoluene sulfonic acid 1-hydrate and hypophosphoric acid, then dehydrated under reduced pressure to obtain 1100 parts of a polyether compound (polyether E3) liquid in state at room temperature and with an acid value (measured according to JIS K 1557) of 3.0.
Polyether E4: EO19.0 mole adduct of lauryl alcohol synthesized in the following Synthesis Example 4
A glass autoclave was charged with lauryl alcohol in an amount of 186 parts (1.0 mole) and KOH 3.3 parts. 836 parts of EO (19.0 moles) were dropwise added at 105° C. over 33 hours from a pressure resistant dropping funnel. Thereafter, the ingredients were reacted at 130° C. for 10 hours, followed by cooling. Further, the resultant mixture was treated with an adsorption treatment agent, filtered, then dehydrated under reduced pressure at 130° C. and 30 mmHg or less to obtain 1000 parts of an EO19.0 mole addition adduct of lauryl alcohol (polyether E4).
Polyether E5: Sanyo Chemical Industriies Polypropylene Glycol “Newpol PP-2000”
Polyether E6: Sanyo Chemical Industrial Polyethylene Glycol “PEG-4000S”
The unvulcanized master batch obtained in the following Examples, tire tread rubber composition and size P205/60R15 pneumatic tire formed using the same for the tread were evaluated for physical properties.
(1) Mooney viscosity: An unvulcanized master batch was used to measure the Mooney viscosity at 100° C., according to JIS K 6300 and evaluated for kneadability/processability. The value of the Mooney viscosity is shown indexed to the value of the standard example as 100. The smaller the value, the better the mixing/processing ability.
(2) ΔG′: A α-Technology RPA2000 was used to measure the strain shear stress G′. The unvulcanized rubber was used for vulcanization at 160° C. for 20 minutes and measured for G′ at a strain of 0.28% to 30.0%. The difference (G′ 0.28 (MPa)-G′ 30.0 (MPa)) was shown as an index. The smaller the value, the better the silica dispersion.
(3) Wet braking performance: Each tire was run over an asphalt road surface sprinkled with water at an initial speed of 40 km/h, then the vehicle braked. The braking distance at this time was measured and indexed to the Standard Example as 100. The larger the value, the better the brakeability shown.
(4) Rolling resistance: The value of the rolling resistance at a vehicle speed of 80 km/h was measured and indexed to the Standard Example as 100. The smaller the value, the lower the value of the rolling resistance shown.
(5) Abrasion resistance: Each tire was run over a dry road surface for 10000 km under conditions of a load corresponding to 88% of the maximum load capacity defined in JATMA (YEAR BOOK 1998) and an air pressure of 200 kPa, then the abrasion of each tire was indexed to the abrasion of the Standard Example. The larger the value, the better the abrasion resistance shown.
The ingredients other than the vulcanization system in each of the formulations shown in Table I were mixed by a 1.8 liter internal mixer for 3 to 5 minutes. When the content reached 165±5° C., the mixture was discharged. This mixture, i.e., the master batch was then mixed with the vulcanization accelerator and sulfur by an 8-inch open roll to obtain a rubber composition. This composition was used to evaluate the Mooney viscosity and ΔG′. On the other hand, this rubber composition was used as the tread to prepare a size P205/60R15 tire by an ordinary method which was then evaluated by its mixing/processing ability and physical properties. The results are shown in Table 1.
The rubber composition for a tire and the pneumatic tire according to the present invention is superior in processability, economy (i.e., low rolling resistance) and safety (i.e., high grip), and therefore, can be used for automobile tires etc.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2004-163501 | Jun 2004 | JP | national |
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/JP05/10207 | 5/27/2005 | WO | 00 | 7/6/2007 |
