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:
An exhaust gas purification device including three-way catalysts connected to engine cylinder groups and arranged in parallel, and a NOx trapping catalyst connected with the three-way catalysts downstream thereof. A controller controls fuel injection for making an A/F ratio of exhaust gas flowing into one of the three-way catalysts rich relative to a stoichiometric A/F ratio when it is required to reduce the NOx trapped by the NOx trapping catalyst.
摘要:
The present invention provides a raw rubber lapping film formed of an ethylene·&agr;-olefin random copolymer comprising ethylene unit and an &agr;-olefin unit having 4 to 20 carbon atoms and a raw rubber bale lapped with this film. Since the film is superior in strength and release properties and has good dispersibility in ethylene·&agr;-olefin copolymer rubber, the operation of lapping raw rubber with a film, the operation of stripping a film from a lapped raw rubber bale and the operation of separating each of a plurality of raw rubber bales are carried out easily and yet there is no adverse effect on the subsequent rubber processing step without stripping the film by heating at a temperature higher than the melting point of the film at the time of kneading.
摘要:
Disclosed herein is an olefin copolymer shrink film comprising an &agr;-olefin/aromatic vinyl compound random copolymer. This &agr;-olefin/aromatic vinyl compound random copolymer comprises 99.9 to 58 mol % of structural units derived from ethylene, 0 to 30 mol % of structural units derived from an &agr;-olefin having 3 to 20 carbon atoms (provided that the total of the structural units derived from ethylene and the structural units derived from an &agr;-olefin having 3 to 20 carbon atoms ranges from 99.9 to 88 mol %), and 0.1 to 12 mol % of structural units derived from an aromatic vinyl compound. The &agr;-olefin/aromatic vinyl compound random copolymer has an intrinsic viscosity [&eegr;], as measured in decalin at 135° C., of 0.1 to 10 dl/g and has a melting point, as measured by a differential scanning calorimeter, of 60 to 125° C. The olefin copolymer shrink film is oriented in at least one direction. The olefin copolymer shrink film has excellent low-temperature shrinkability and transparency.
摘要:
Disclosed is an olefin thermoplastic elastomer composition obtained by dynamically heat treating, in the presence of an organic peroxide, a blend comprising 10 to 60 parts by weight of a crystalline polyolefin resin (A) and 40 to 90 parts by weight of an unsaturated olefin copolymer (B) of at least one .alpha.-olefin of 2 to 20 carbon atoms, a conjugated diene monomer represented by the following formula (I), and optionally, an aromatic vinyl compound, the total amount of said components (A) and (B) being 100 parts by weight; ##STR1## wherein R.sup.1 and R.sup.2 are each independently a hydrogen atom, an alkyl group of 1 to 8 carbon atoms or an aryl group, and at least one of R.sup.1 and R.sup.2 is a hydrogen atom. The composition has excellent moldability and can provide a molded product having excellent elastomeric properties, tensile strength properties and appearance.
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.
摘要:
Disclosed is a foamable olefin thermoplastic elastomer composition comprising (A) a partially crosslinked thermoplastic elastomer composition, (B) long-chain branch-containing polypropylene and (C) a foaming agent. The partially crosslinked thermoplastic elastomer composition (A) is obtained by dynamically heat-treating a mixture in the presence of organic peroxide, said mixture comprising specific proportions of a peroxide-crosslinking type olefin copolymer rubber (a), which is an ethylene/.alpha.-olefin copolymer rubber composed of ethylene, an .alpha.-olefin of 3 to 20 carbon atoms and optionally a nonconjugated diene, and a peroxide-decomposition type olefin plastic (b), which is an .alpha.-olefin (co)polymer containing a specific amount of an .alpha.-olefin of 3 to 20 carbon atoms and having a specific MFR. Also disclosed is a foamed product obtained by heating the foamable olefin thermoplastic elastomer composition. From the foamable olefin thermoplastic elastomer composition, a foamed product having an expansion ratio of at least 2 times, being free from surface roughening caused by defoaming, being soft to the touch and showing excellent heat resistance and weathering resistance can be produced with high productivity through simplified steps.
摘要:
A crosslinked foamed body obtained by subjecting a rubber compounded product comprising (A) a chlorinated ethylene/.alpha.-olefin copolymer rubber, (B) a triazinethiol as a vulcanization agent, (C) an alkyl ammonium halide as a vulcanization promotor, and (D) a hydrazide-type blowing agent to two step vulcanization and foaming at a vulcanization temperature of 120.degree. to 140.degree. C. for a vulcanization time of 5 to 10 minutes in a first step and at a vulcanization temperature of 125.degree. to 160.degree. C. for a vulcanization time of 5 to 20 minutes in a second step, the second step vulcanization temperature being higher than the first step by at least 5.degree. C., so that the expansion factor will be 3 to 10 times. This crosslinked foamed body can be colored brilliantly, exhibit excellent weatherability, suppleness and shape retention as well as good outer appearance. This product is well usable, for example, as wet suits.
摘要:
A spiral wound gasket having an annular body serving as a centering member which is integrally disposed at the inner periphery side of a gasket body formed by winding, in the form of a spiral. The gasket body comprises a metal hoop material and a filler material overlapping each other. When this gasket is disposed at fit-joint-type pipe connection portions of the exhaust pipe system in a motor vehicle, the annular body serves as a centering member to prevent the gasket body from protruding into the fit joint. This prevents the gasket body from deterioration and damage, thus assuring a high sealing property for a long period of time. Further, merely by inserting and fitting the gasket, the gasket may be automatically aligned and positioned with respect to the fit joint. Further, the inner peripheral surface of the gasket body and the annular body form an annular closed space, thus making the entire gasket into a lightweight design.
摘要:
The present invention is a polyolefin polymer containing vinyl groups at both ends thereof, and a composition and a molded product containing the polymer, wherein the polymer contains a constitutional unit derived from at least one selected from the group consisting of ethylene (a), an α-olefin (b) having 3 to 20 carbon atoms, and a cyclic olefin (c), and (1) a ratio of terminal vinylation is 70% or more relative to all of both ends of molecular chains, and (2) an intrinsic viscosity [η] is in the range of 0.01 to 10 dl/g as measured in a decalin solution at 135° C. The polymer of the present invention may be molded by a LIM molding, an injection molding, a transfer molding, a compression molding, and the like, and is excellent in acid resistance, gas permeation resistance, hydrolysis resistance, and dynamic fatigue resistance. From the polymer, a thermoplastic resin composition and a crosslinkable resin composition, and a crosslinked composition having excellent mechanical characteristics are obtained.