摘要:
A lubricating oil composition for a power transmission system, which is excellent in both of low-temperature viscosity property and shear stability, is provided. The viscosity modifier of a lubricating oil for a power transmission system according to the present invention comprises an ethylene/α-olefin copolymer (B) having the properties: (B1) an ethylene content in the range of 70 to 85% by mol, (B2) an intrinsic viscosity [η] in the range of 0.2 to 1.0 dl/g, (B3) Mw/Mn not more than 2.4, and (B4) a melting point, as measured by DSC, not higher than 60° C., or no melting point observed.
摘要:
A lubricating oil composition for a power transmission system, which is excellent in both of low-temperature viscosity property and shear stability, is provided. The viscosity modifier of a lubricating oil for a power transmission system according to the present invention comprises an ethylene/α-olefin copolymer (B) having the properties: (B1) an ethylene content in the range of 70 to 85% by mol, (B2) an intrinsic viscosity [η] in the range of 0.2 to 1.0 dl/g, (B3) Mw/Mn not more than 2.4, and (B4) a melting point, as measured by DSC, not higher than 60° C., or no melting point observed.
摘要:
The present invention provides a lubricating oil composition having excellent low temperature viscosity properties suitable for engine oils for automobiles and industries, gear oils, shock absorber oils, hydraulic fluids and it also provides a lubricating oil for internal-combustion engines formed from the composition. The lubricating oil composition comprises; a lubricating oil base (A) having a kinematic viscosity at 100° C. of 1 to 50 mm2/s and a viscosity index of not less than 80, an ethylene•propylene copolymer (B) having the following properties (B1) to (B4) such that (B1) the ethylene content is from 30 to 75% by weight, (B2) the intrinsic viscosity [η] is from 1.3 to 2.0 dl/g, (B3) the Mw/Mn is not more than 2.4 and (B4) the melting point as measured with DSC is not higher than 30° C., and optionally a pour point depressant (C).
摘要:
The present invention provides a lubricating oil composition having excellent low temperature viscosity properties suitable for engine oils for automobiles and industries, gear oils, shock absorber oils, hydraulic fluids and it also provides a lubricating oil for internal-combustion engines formed from the composition.The lubricating oil composition comprises; a lubricating oil base (A) having a kinematic viscosity at 100° C. of 1 to 50 mm2/s and a viscosity index of not less than 80, an ethylene•propylene copolymer (B) having the following properties (B1) to (B4) such that (B1) the ethylene content is from 30 to 75% by weight, (B2) the intrinsic viscosity [η] is from 1.3 to 2.0 dl/g, (B3) the Mw/Mn is not more than 2.4 and (B4) the melting point as measured with DSC is not higher than 30° C., and optionally a pour point depressant (C).
摘要:
A process for producing a rubber composition containing a nonconjugated polyene copolymer (A), a softener (B) and a diene rubber (C), comprising: a step of mixing a copolymer composition (I), said copolymer composition (I) comprising 100 parts by weight of a nonconjugated polyene copolymer (A), said nonconjugated polyene copolymer (A) being a random copolymer containing 96 to 70 mol % of the structural units derived from α-olefin (A1) and 4 to 30 mol % of the structural units derived from nonconjugated polyene (A2) and having a glass transition temperature (Tg) of −25 to 20° C., and 1 to 100 parts by weight of the softener (B); the diene rubber (C); and optionally further the softener (B). A tire tread using the rubber composition and a tire having the tire tread.
摘要:
A novel and useful linear triene compound represented by the following formula (1) is co-polymerized with an &agr;-olefin to obtain an ethylenically unsaturated copolymer which is superior in weather-ability, heat resitance and fastness to ozone, together with superior scorch stability and vulcanizability at high velocity in which R1, R2, R3, R4, R5 and R6 stand each, independently of each other, for hydrogen atom or an alkyl having 1-3 carbon atoms, R7 represents an alkyl having 1-3 carbon atoms and n is an integer of 0-5, with the proviso that each of R4s or of R5s may be identical with or different from each other, respectively, when n is 2 or greater.
摘要:
The higher .alpha.-olefin copolymers obtained in accordance with the present invention are copolymers derived from higher .alpha.-olefin and non-conjugated diene represented by the following general formula [I], and (a) the non-conjugated diene content thereof is from 0.01 to 30 mol %, and (b) the intrinsic viscosity [.eta.], as measured in decahydronaphthalene at 135.degree. C., of said copolymer is from 1.0 to 10.0 dl/g. ##STR1## The invention also provides a process for preparing such higher .alpha.-olefin copolymers as illustrated above, and vulcanization products obtained from said copolymers.Furthermore, the invention provides vulcanizable compositions containing rubber comprising of the above-mentioned higher .alpha.-olefin copolymers and a specific diene rubber or a specific ethylene/.alpha.-olefin copolymer rubber.
摘要:
Provided is a rubber composition which can give a tire excellent in braking performance and fuel consumption and which is excellent in mechanical strength and fatigue resistance, and a use thereof.The rubber composition of the present invention contains a (A) 60 to 0.1 parts by weight of a nonconjugated polyene copolymer, which is a random copolymer containing 96 to 70 mol % of the structural units derived from α-olefin (A1) and 4 to 30 mol % of the structural units derived from a nonconjugated polyene (A2), and has a glass transition temperature (Tg) of −25 to 20° C., (B) 40 to 99.9 parts by weight of a diene rubber and (C) at least one selected from the group consisting of specific polymers.
摘要:
A tire provided with a tire tread made from a rubber composition comprising (A) a random copolymer based on non-conjugated cyclic polyene comprising structural units originated from one or more &agr;-olefins (A1) and originated from one or more non-conjugated cyclic polyene (A2), the said random copolymer having a content of the structural unit(s) originated from one or more &agr;-olefins (A1) in the range of 93 to 70 mole %; a content of the structural unit originated from one or more non-conjugated cyclic polyene (A2) in the range of 7 to 30 mole %; an intrinsic viscosity [&eegr;], determined in decalin at 135° C., in the range of 0.01 to 20 dl/g; a glass transition temperature (Tg) of not higher than 40° C.; and an iodine value in the range of 50 to 150, and (B) a rubber based on diene, in a weight proportion of {the random copolymer based on non-conjugated cyclic polyene (A)} versus {the rubber based on diene (B)} in the range from 60/40 to 0.1/99.9 exhibits a superior braking performance and, compatible therewith, a superior driving fuel cost aspect.
摘要:
Disclosed is a process for preparing an ethylene-.alpha.-olefin-nonconjugated polyene random copolymer comprising random copolymerizing (a) ethylene, (b) an .alpha.-olefin of 3 or more carbon atoms and (c) a nonconjugated polyene in the presence of a metallocene catalyst containing a specific metallocene compound. The ethylene-.alpha.-olefin-nonconjugated polyene random copolymer prepared by the process has such properties that (i) the copolymer contains units derived from ethylene (a) and units derived from the .alpha.-olefin of 3 or more carbon atoms (b) in a molar ratio of 40/60 to 95/5 �(a)/(b)!, (ii) the iodine value is 1 to 50, (iii) the intrinsic viscosity (.eta.) is more than 0.1 dl/g and less than 8.0 10 dl/g, (iv) the intensity ratio D of T.alpha..beta. to T.alpha..alpha. in the .sup.13 C-NMR spectrum, T.alpha..beta./T.alpha..alpha., is not more than 0.5, (v) the B value is 1.00 to 1.50, (vi) the glass transition temperature Tg is not higher than -50.degree. C., and (vii) the ratio g.eta.* of the intrinsic viscosity (.eta.) of this copolymer defined above to the intrinsic viscosity (.eta.).sub.blank of a straight-chain ethylene-propylene copolymer having the same weight-average molecular weight as this random copolymer and having an ethylene content of 70% by mol, (.eta.)/(.eta.).sub.blank, is more than 0.9. Also disclosed is a vulcanizable rubber composition containing the random copolymer. The ethylene-.alpha.-olefin-nonconjugated polyene random copolymer and the rubber composition are excellent in mechanical strength, weathering resistance, ozone resistance, processability, low-temperature flexibility and heat resistance.