Method for purifying bisimides

Organic compounds -- part of the class 532-570 series – Organic compounds – Heterocyclic carbon compounds containing a hetero ring...

Reexamination Certificate

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

Reexamination Certificate

active

07408070

ABSTRACT:
A method for purifying bisimides is provided. In one aspect, purified oxybisphthalimides, intermediates useful in the preparation of polyetherimides are provided. In one embodiment, a first solution containing a bisimide compound, a solvent, and a phase transfer catalyst is contacted with a solid inorganic adsorbent material having a total pore volume of about 0.5 milliliters/gram or greater and a cumulative pore volume distribution of about 20 percent or greater of particles having a pore diameter in a range between about 3 nanometers and about 20 nanometers. The solution containing the bisimide compound is then separated from the solid inorganic adsorbent material to provide a purified bisimide compound which is substantially free of the phase transfer catalyst. The purification technique is especially valuable for preparing high purity oxybisphthalimides, such as 4,4′-oxybis(N-methylphthalimide), which are substantially free of residual phase transfer catalyst.

REFERENCES:
patent: 4870194 (1989-09-01), Molinaro et al.
patent: 4906760 (1990-03-01), Mueller et al.
patent: 4933469 (1990-06-01), Berdahl et al.
patent: 5081298 (1992-01-01), Brunelle
patent: 5145971 (1992-09-01), Lesins
patent: 6028203 (2000-02-01), Brunelle et al.
patent: 6706897 (2004-03-01), Brunelle et al.
patent: 6727370 (2004-04-01), Brunelle et al.
patent: 1674443 (2006-06-01), None
Elliot P. Barrett et al., “The Determination of Pore Volume and Area Distributions in Porous Substances. I. Computations From Nitrogen Isotherms”, Contribution from the Multiple Fellowship of Baugh and Sons Company, Mellon Institute, vol. 73, pp. 373-380, Jan. 1951.

LandOfFree

Say what you really think

Search LandOfFree.com for the USA inventors and patents. Rate them and share your experience with other people.

Rating

Method for purifying bisimides does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Method for purifying bisimides, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method for purifying bisimides will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFUS-PAI-O-4007444

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.