Synthetic resins or natural rubbers -- part of the class 520 ser – Synthetic resins – Polymerizing in tubular or loop reactor
Reexamination Certificate
2004-10-27
2010-06-15
Cheung, William K (Department: 1796)
Synthetic resins or natural rubbers -- part of the class 520 ser
Synthetic resins
Polymerizing in tubular or loop reactor
C526S065000, C526S073000, C526S348200
Reexamination Certificate
active
07737229
ABSTRACT:
The invention relates to a process for the continuous preparation of ethylene homopolymers or copolymers in the presence of free-radical polymerization initiators and, if desired, molecular weight regulators at from 120° C. to 350° C. and pressures in the range from 100 to 4000 bar, in which the polymer is separated from unpolymerized ethylene in a high-pressure stage at a pressure of from 100 to 500 bar and at least one low-pressure stage at a pressure of from 1 to 100 bar and the ethylene separated off in the high-pressure stage is separated from remaining monomeric, oligomeric and/or polymeric constituents and recirculated to the inlet of the tube reactor in a high-pressure circuit and the ethylene separated off in the low-pressure stage is separated from remaining monomeric, oligomeric and/or polymeric constituents and recirculated to the inlet of the tube reactor in a low-pressure circuit. The initiator is used as a solution in an isoparaffinic solvent having a boiling point of not more than 160° C. and the solvent is separated from the other monomeric, oligomeric and/or polymeric constituents in the low-pressure circuit. The solvent is then, if appropriate after being admixed with fresh solvent, reused for dissolving initiator.
REFERENCES:
patent: 3275615 (1966-09-01), Krulisch
patent: 5100978 (1992-03-01), Hansenbein et al.
patent: 6355741 (2002-03-01), Marechal
patent: 2003/0008982 (2003-01-01), Mahling et al.
patent: 2004/0181015 (2004-09-01), Deckers et al.
patent: 4102808 (1991-01-01), None
patent: 394794 (1992-03-01), None
patent: 567818 (1992-03-01), None
patent: 449092 (1994-11-01), None
patent: 2362869 (1978-03-01), None
patent: 823932 (1956-06-01), None
patent: 1558883 (1976-08-01), None
patent: WO 03/018646 (2003-06-01), None
Ullmann's Encyclopedia der technischen Chemie, 4thEdition, vol. 19, p. 169-178 (1980).
Dröge Thomas
Gonioukh Andrei
Köhler Gernot
Teuber Theo
Basell Polyolefine GmbH
Cheung William K
Guo Shao-Hua
LandOfFree
Continuous preparation of ethylene homopolymers or copolymers does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Continuous preparation of ethylene homopolymers or copolymers, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Continuous preparation of ethylene homopolymers or copolymers will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-4158283