摘要:
Tire, including at least one structural element including a crosslinked elastomeric material obtained by crosslinking a crosslinkable elastomeric composition, includes: (a) at least one diene elastomeric polymer; (b) at least one activator obtained by dry comilling a mixture including: at least one salt, or one oxide, or one hydroxide of a metal belonging to groups 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, or 16 of the Periodic Table of the Elements; and at least one layered material, said layered material having an individual layer thickness of 0.01 nm to 30 nm, preferably 0.05 nm to 15 nm, and more preferably 0.1 nm to 2 nm; (c) at least one vulcanization accelerator; and (d) sulfur or derivatives thereof.
摘要:
A tire includes: a carcass structure including at least one carcass ply, of a substantially toroidal shape, having opposite lateral edges associated with respective right-hand and left-hand bead structures, the bead structures including at least one bead core and at least one bead filler; a belt structure applied in a radially external position with respect to the carcass structure; a tread band radially superimposed on the belt structure; a pair of sidewalls applied laterally on opposite sides with respect to the carcass structure; at least one layer including a crosslinked elastomeric material having air barrier properties, wherein the crosslinked elastomeric material is obtained by crosslinking a crosslinkable elastomeric composition including: (a) 10 phr or 100 phr, preferably 20 phr to 60 phr, of at least one butyl rubber; (b) 0 phr to 90 phr, preferably 40 phr to 80 phr, of at least one diene elastomeric polymer; (c) 5 phr to 120 phr, preferably 15 phr to 90 phr, of at least one reinforcing filler; (d) 2 phr to 20 phr, preferably 5 phr to 15 phr, of at least one copolymer of at least one ethylenically unsaturated carboxylic acid or a derivative thereof with at least one ethylenically unsaturated monomer containing at least one polyoxyalkylene side chain.
摘要:
Tire having at least one structural element including a crosslinked elastomeric material obtained by crosslinking a crosslinkable elastomeric composition containing (a) 100 phr of at least one diene elastomeric polymer; (b) 1 phr to 50 phr, preferably 2 phr to 40 phr, and more preferably 5 phr to 30 phr, of at least one layered material having an individual layer thickness of 0.01 nm to 30 nm, preferably 0.05 nm to 15 nm; (c) 0.1 phr to 15 phr, preferably 0.3 phr to 10 phr, of at least one methylene donor compound; and (d) 0.4 phr to 20 phr, preferably 0.8 phr to 15 phr of at least one methylene acceptor compound. Preferably, the at least one structural element is selected from bead filler, sidewall insert tread underlayer, or tread base.
摘要:
A class of bridged or unbridged metallocene compounds is disclosed, wherein the cyclopentadienyl ligands have two or four adjacent substituents forming one or two alkylenic cycles of from 4 to 8 carbon atoms.These metallocenes are useful as catalyst components for the polymerization of olefins, particularly for the (co)polymerization of ethylene and for the polymerization of propylene.
摘要:
A process for the preparation of heterophasic elastomeric polymer comprising the step of polymerizing ethylene, an alpha-olefin CH2═CHL, where L is an alkyl, cycloalkyl or aryl radical with 1–10 carbon atoms and a non-conjugated diene in the presence of a catalyst system comprising a transition metal catalyst component supported on a porous alpha-olefin polymer, characterized in that at least part of the diene is impregnated on the porous alpha-olefin polymer.
摘要:
Tyre for vehicle wheels, comprising at least one component made of a crosslinked elastomeric material, in which said component includes an elastomeric composition comprising: (a) at least one diene elastomeric polymer, (b) at least one cycloolefin polymer, said cycloolefin polymer having a glass transition temperature (Tg) of not less 50° C. Preferably, said component including said composition is a tyre tread band.
摘要:
Ethylene based polymers having high molecular weights can be obtained in high yields at temperatures of industrial interest, by carrying out the polymerization reaction in the presence of catalysts comprising silicon bridged metallocenes having a particular ligand system containing a heteroatom.
摘要:
Catalysts for the polymerization of olefins are disclosed, comprising the product obtainable by contacting: (A) a bridged and/or substituted cyclopentadienyl compound of Ti, Zr or Hf; (B) one or more organometallic aluminium compounds of formula (II): AlR43−zHz wherein the substituents R4, same or different from each other, are linear or branched, saturated or unsaturated C1-C20 alkyl or alkylaryl radicals, optionally containing Si or Ge atoms, wherein at least one of the substituents R4 is different from a straight alkyl group; z is 0 or 1; and (C) water, the molar ratio between the organometallic aluminium compound and water being comprised between 1:1 and 100:1; said catalyst being obtainable by a process comprising the following steps: (i) contacting component (A) with part of component (B) in the absence of component (C); (ii) contacting part of component (B) with component (C) in the absence of component (A) and successively (iii) contacting the products obtained in steps (i) and (ii).