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    53.
    发明专利
    未知

    公开(公告)号：DE69826422T2

    公开(公告)日：2005-03-03

    申请号：DE69826422

    申请日：1998-11-18

    Applicant: BRIDGESTONE CORP

    Inventor： HALL JAMES E ,  GRAVES DANIEL F ,  TAKEICHI HIDEO

    IPC: C08F2/06 ,  C08F297/04

    Abstract: The dispersibility of the initial polystyrene block in forming a S-B-S type of copolymer is improved by first preparing a small block of homopolydiene such as homopolybutadiene as a dispersing agent. Onto this small block of homopolybutadiene, the first block of polystyrene is formed and affixed and thereby made dispersible in a mixture of alkanes and 15 to 60% by weight of cycloalkanes, preferably hexane and cyclohexane. After the preparation of the dispersing agent and the first styrene block, the remaining monomer charges to the reactor are fed in aliphatic hydrocarbon diluents, preferably hexane or technical hexane, thereby greatly reducing the final percentage of cycloalkanes including cyclohexane in the reactor to less than 25% of total dispersing medium. The block copolymers produced according to the present process display a narrow molecular weight distribution and improved tensile strength over block copolymers produced in the absence of the additional cycloalkanes in the solvent system.

    54.
    发明专利
    未知

    公开(公告)号：DE69720369T2

    公开(公告)日：2003-10-16

    申请号：DE69720369

    申请日：1997-10-15

    Applicant: BRIDGESTONE CORP

    Inventor： HALL JAMES E

    IPC: C08F2/00 ,  C08F4/44 ,  C08F4/50 ,  C08F4/56 ,  C08F36/04 ,  C08F297/04 ,  C08G85/00 ,  C07F3/02

    Abstract: The invention is a practical process for anionically synthesizing commercially significant quantities of macrocyclic polymers from polar and/or non-polar monomers by using Group IIA and IIB metal cyclic organometallic initiators. Activation of the ring metal atom results in anionic polymerization of the monomers by addition into the initiator ring at the bonds between the atom and its two adjacent carbon atoms, the metal atom acting as a bridge between the two living ends of the propagating chain. Coupling of the cyclic polymer living ends by coupling agents produces macrocyclic polymers that are stable in air and moisture and that exhibit desirable properties, such as low viscosities at high molecular weights. Such macrocyclic polymers provide enhanced polymer processability during molding, extruding and the forming of films. Macrocyclic polymers terminated with coupling agents that also provide functional groups may be compounded to produce vulcanizable elastomeric compounds and articles that exhibit reduced hysteresis properties.

    55.
    发明专利
    未知

    公开(公告)号：DE69720138D1

    公开(公告)日：2003-04-30

    申请号：DE69720138

    申请日：1997-10-15

    Applicant: BRIDGESTONE CORP

    Inventor： HALL JAMES E

    IPC: B60C1/00 ,  C08F4/44 ,  C08F4/50 ,  C08F8/00 ,  C08F10/00 ,  C08F36/00 ,  C08F36/04 ,  C08K3/04 ,  C08K3/36 ,  C08L9/00 ,  C08L57/00 ,  C08F297/04

    Abstract: The present invention provides a method of anionic synthesis of stable macrocyclic polymers that are compounded to form vulcanizable elastomeric compounds exhibiting reduced hysteresis properties. Cyclic organometallic compounds containing divalent metal atoms of Groups IIA and IIB of the Periodic System are employed as initiators of anionic polymerization of conjugated diene, vinyl aromatic and/or triene monomers. Coupling of the living ends of the resulting macrocyclic polymers or copolymers with a coupling agent or a coupling agent that is also a functionalizing agent results in stable macrocyclic polymers with improved hysteresis properties.

    59.
    发明专利
    未知

    公开(公告)号：ES2116501T3

    公开(公告)日：1998-07-16

    申请号：ES94116325

    申请日：1994-10-17

    Applicant: BRIDGESTONE CORP

    Inventor： HALL JAMES E ,  ROGGEMAN DAVID M

    IPC: C08F2/44 ,  C08F2/00 ,  C08F212/00 ,  C08F212/06 ,  C08F236/10 ,  C08F297/04 ,  C08L53/02 ,  C08L25/08

    Abstract: In accordance with the present invention, a continuous polymerization process is provided for the preparation of a rubbery copolymer by the non-aqueous dispersion random polymerization of a mixture of 30 to 65% by weight of a conjugated diolefin monomer, preferably butadiene, and 35 to 70% by weight of a vinyl substituted aromatic monomer, preferably styrene, in a liquid aliphatic hydrocarbon dispersion medium with an anionic initiator catalyst system in the presence of a block copolymeric dispersing agent which is continuously prepared in-situ. At least one block of the dispersing agent is continuously prepared prior to the dispersion polymerization reaction and a second block of the dispersing agent and a rubbery copolymer are continuously prepared in-situ during the dispersion copolymerization. The second block of the dispersing agent has the polymer structure of the continuously produced rubbery copolymer.

    60.
    发明专利
    未知

    公开(公告)号：ES2114899T3

    公开(公告)日：1998-06-16

    申请号：ES92115066

    申请日：1992-09-03

    Applicant: BRIDGESTONE CORP

    Inventor： HALL JAMES E

    IPC: C08F2/00 ,  C08F2/38 ,  C08F36/00 ,  C08F236/04 ,  C08F236/10 ,  C08F297/04

    Abstract: A process for preparing continuously tapered polymers and copolymers having a continuous change in microstructure along the polymer backbone is disclosed. The process produces polymers and copolymers with multiple glass transition temperatures of very small energy absorption, i.e. no definable glass transition temperature. The polymers have a flexible chain end and they progressively become stiffer along the length of the chain.

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