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    191.
    发明专利
    未知

    公开(公告)号：ES2058658T3

    公开(公告)日：1994-11-01

    申请号：ES90107146

    申请日：1990-04-14

    Applicant: BASF AG

    Inventor： PIPPER GUNTER ,  KOCH ECKHARD MICHAEL DR

    IPC: C08G69/28

    Abstract: A process for the continuous preparation of polytetramethylene adipamide, in which (a) an aqueous solution of the salt of 1,4-diaminobutane and adipic acid is heated with evaporation of water to form a vapor phase and a molten prepolymer, (b) the said prepolymer and vapor phase are passed, to effect thorough mixing thereof, through a mass transfer zone equipped with baffles and located immediately downstream of stage (a), (c) the said vapor phase is separated from the polymer in a separting zone and the polymer is discharged in the form of a melt capable of being granulated, with the proviso that the total residence time in stages (a), (b) and (c) is less than 5 minutes, and (d) pyrrolidine is distilled off from the vapor phase separated in stage (c) and 1,4-diaminobutane is recycled to the vaporizing stage (a).

    195.
    发明专利
    未知

    公开(公告)号：DE3912769A1

    公开(公告)日：1990-10-25

    申请号：DE3912769

    申请日：1989-04-19

    Applicant: BASF AG

    Inventor： PIPPER GUNTER ,  KOCH ECKHARD MICHAEL DR

    IPC: C08G69/28 ,  C08G69/36 ,  C08G69/40 ,  C08G69/46

    Abstract: A process for the continuous preparation of a linear polyamide having ether bridges in the polymer chain, in which an aqueous solution of a salt of a diamine and an equimolar amount of a dicarboxylic acid, which may additionally contain a lactam or the corresponding aminocarboxylic acid, from 1 to 80% of the polyamide-forming units, based on the total polyamide-forming units, being diamine and/or dicarboxylic acid units which, after removal of the amine groups or carboxyl groups, have radicals of formula I -R1-O-R2-O]R3-I, in which R1, R2 and R3 are the same or different and denote alkylene radicals of from 2 to 6 carbon atoms, which may contain alkyl radicals of from 1 to 3 carbon atoms as substituents, and n is an integer from 1 to 60, is passed for a short period of time through a prepolymerization zone, the resulting mixture of prepolymer and vapor is intimately mixed and then separated, the vapor fraction obtained is separated to give an aqueous amine solution, which is recycled to the precondensation zone, the prepolymer is further condensed, discharged with the removal of water vapor, solidified and granulated and the polymer granules are further condensed, to the desired viscosity, in the solid phase under a blanket of an inert gas.

    198.
    发明专利
    未知

    公开(公告)号：DE3710803A1

    公开(公告)日：1988-10-20

    申请号：DE3710803

    申请日：1987-03-31

    Applicant: BASF AG

    Inventor： PIPPER GUNTER ,  CORDES CLAUS DR

    IPC: C08G69/16 ,  C08G69/46

    Abstract: Caprolactam and oligomers thereof are removed from nylon granules containing same in a process wherein (a) nylon granules are introduced at not less than 100 DEG C. at the top of a substantially upright treatment zone, (b) nylon granules are passed downward through the treatment zone while being heated to from 130 DEG to 210 DEG C., (c) superheated steam is passed at from 130 DEG to 210 DEG C. upward through the treatment zone, (d) dry nylon granules are withdrawn at the bottom end of the treatment zone and steam containing caprolactam and oligomers thereof is withdrawn at the top of the treatment zone, (e) the caprolactam and oligomers thereof containing steam thus obtained is passed through a column giving an aqueous solution of caprolactam and oligomers thereof as bottom product and virtually caprolactam-free steam as overhead product.

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