摘要:
The invention concerns a crosslinkable or crosslinked rubber composition having improved hysteretic properties when crosslinked which is useful for forming a tyre running tread, a method for preparing said crosslinkable composition, such a running tread and a tyre having reduced rolling resistance. Said composition is characterised in that it consists of: at least a diene elastomer having a mol ratio of units derived from conjugate dienes higher than 30 % and comprising carboxylic acid functions along its chain, and a reinforcing inorganic filler.
摘要:
The invention relates to a method for the continuous preparation of a catalytic system that can be used for the polymerisation of at least one conjugated diene monomer, said catalytic system being based on at least: a conjugated preformation diene; a salt of one or more rare earth metal(s) of an organic phosphoric acid, said salt being in suspension in at least one saturated inert hydrocarbon solvent of the aliphatic or alicyclic type; an alkylation agent comprising an alkylaluminium having formula A1R3 or HA1R2; and a halogen donor comprising an alkylaluminium halide. The inventive method is characterised in that it comprises the following successive steps in one line (L), namely: (i) a reaction between the conjugated preformation diene with the rare earth salt solution and the alkylation agent and the continued alkylation reaction for a minimum characteristic period of at least 5 minutes in an alkylation reactor (30) consisting of at least one well-mixed-type dynamic mixer, and (ii) the addition of the halogen donor to the mixture obtained in (i) in order to produce a reaction for the halogenation/ageing of the preformed catalytic system and continuous production of the preformed catalytic system at the output of the line (L).
摘要:
The invention concerns a method for preparing a diene elastomer. The invention is applicable in particular for obtaining a polybutadiene with a high proportion of cis-1,4 sequences having both a Mooney viscosity (ML1+4) not less than 40, a polydispersity index less than 2.1 and a reduced cold creep and a polyisoprene. The inventive method includes reacting a catalytic system with at least one conjugated diene monomer, said catalytic system being based on at least: one conjugated diene, one or more rare earth metal salts of an organic phosphoric acid, said salt being suspended in at least one inert and saturated hydrocarbon solvent of aliphatic or alicyclic type, an alkylating agent consisting of an alkylaluminium of formula AIR3 or HAIR2, and a halogen donor belonging to the family of alkylaluminium halides, excluding alkylaluminium sesquihalides. Said method includes offset contacting of the monomer(s) to be polymerized with at least one alkylaluminium compound of formula AIR3 or HAIR2 which is identical or not to the alkylating agent of said catalytic system, said amount being selected based on the characteristics of the polymerization medium and/or polymerization conditions and/or said elastomer to be obtained.
摘要:
The invention relates to an elastomer mixture resulting from the modification of a diene elastomer by a coupling agent that inserts an alkoxysilane bearing a tertiary or secondary amine function into the elastomer chain. The mixture mainly comprises a diene elastomer coupled by the alkoxysilane group bearing a tertiary or secondary amine function bonded to the diene elastomer via the silicon atom. The invention also relates to a reinforced rubber composition which can be used in particular to make tyres and which comprises a reinforcing filler as well as an elastomer matrix including at least said elastomer mixture, and to a method for preparing same. The composition has improved hysteretic and mechanical properties in the vulcanised state and improved processability in the green state.
摘要:
The invention relates to synthetic branched polyisoprenes having a macrostructure and a microstructure which are very similar to those of natural rubber. According to one aspect of the invention, said polyisoprenes have an apparent stress F/S0 which is equal to or greater than 0.4 MPa for an elongation α of 150 % which is applied to a dumb-bell-shaped test piece containing cross-linkable polyisoprene. According to another aspect of the invention, said polyisoprenes satisfy relation (i) Cotan δ = 0.3761. θinh + 0.15, wherein: cotan δ is the cotangent of the loss angle of a sample of the polyisoprene, which is measured at 130° C using a device with the trade name RPA2000, said sample being shear stressed at 10 % of deformation and at a stress frequency of 0.035 Hz; and θinh is the inherent viscosity of the polyisoprene, which is measured in toluene at 25° C and with a 0.1 g/dl concentration of polyisoprene in the toluene.
摘要:
The invention concerns a catalytic system used for preparing polybutadienes by polymerization, a method for preparing said catalytic system and a method for preparing polybutadienes using said catalytic system. The inventive catalytic system is based on at least: a conjugated diene monomer, a salt of one or more rare earth metals of an organic phosphoric acid, said salt being suspended in at least a saturated inert hydrocarbon solvent of aliphatic or alicyclic type, an alkylating agent consisting of an alkylaluminium of formula AIR3 or HalR2, the mol ratio (alkylating agent/ rare earth salt) being greater than 5, and a halogen donor belonging to the family of alkylaluminium halides other than alkylaluminium sesquihalides, and in accordance with the invention, said catalytic system comprises said rare earth metal(s) in a concentration not less than 0.005 mole/l.
摘要:
The invention concerns a method for obtaining a 1,3-butadiene homopolymer which consists in reacting a catalytic system in the presence of 1,3-butadiene and one or more mono-olefin(s) of 4 carbon atoms. The invention is characterized in that said catalytic system is based on at least: one conjugate diene monomer, one salt of one or more rare earth metals of an organic phosphoric acid, said salt being suspended in at least a saturated, inert hydrocarbon solvent of the aliphatic or alicyclic type, an alkylating agent consisting of alkylaluminium of formula AlR3 or HalR2, wherein R is an alkyl group, and a halogen donor consisting of alkylaluminium halide.
摘要:
The invention relates to a process for preparing, in one step, a diene block copolymer, of which at least one of these blocks is constituted of a polyether for which the number-average molecular weight is essentially from 100 to 5000 g/mol, and at least another of these blocks is constituted of a diene elastomer. The process according to the invention allows a high degree of grafting of the polyether to the polymer chains. The present invention also relates to a reinforced rubber composition, especially intended for manufacturing tyres, comprising such a block copolymer that is intended to interact with the reinforcing filler. A rubber composition according to the invention has improved hysteresis properties in the vulcanized state, while retaining satisfactory processing properties in the non-vulcanized state.
摘要:
The invention concerns a method for preparing a diene elastomer. The invention is applicable in particular for obtaining a polybutadiene with a high proportion of cis-1,4 sequences having both a Mooney viscosity (ML1+4) not less than 40, a polydispersity index less than 2.1 and a reduced cold creep and a polyisoprene. The inventive method includes reacting a catalytic system with at least one conjugated diene monomer, said catalytic system being based on at least: one conjugated diene, one or more rare earth metal salts of an organic phosphoric acid, said salt being suspended in at least one inert and saturated hydrocarbon solvent of aliphatic or alicyclic type, an alkylating agent consisting of an alkylaluminium of formula AIR3 or HAIR2, and a halogen donor belonging to the family of alkylaluminium halides, excluding alkylaluminium sesquihalides. Said method includes offset contacting of the monomer(s) to be polymerized with at least one alkylaluminium compound of formula AIR3 or HAIR2 which is identical or not to the alkylating agent of said catalytic system, said amount being selected based on the characteristics of the polymerization medium and/or polymerization conditions and/or said elastomer to be obtained.