Interfacially polymerized polyester films
AssigneeThe Cynara Company
InventorsPaul G. Glugla, Gregory K. Rickle, Bethanne L. Smith, Stephen E. Bales
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Abstract
The present invention concerns a polyester gas separation membrane which is obtained by the interfacial polymerization of benzenetricarbonyl trihalide or benzene tetracarbonyl tetrahalide in a water-insoluble organic solvent in one phase and a variety of polyfunctional phenols present as the di- or tri-salt in a mixture of water and phase transfer agent and a water-soluble organic solvent in the second phase. The present invention also includes the polyester membrane itself, its methods of preparation and the use of the membranes to separate gas mixtures, such as carbon dioxide and methane, helium and methane and the like.
Claims23
A crosslinked polyester glassy polymer in the form of a membrane produced by interfacial polymerization, said polymer including ##STR13## trifunctional groups or ##STR14## tetrafunctional groups having the general structure:
- ##STR15## A is selected from the group consisting of:
- ##STR16## A.sup.1 is selected from the group consisting of;
- ##STR17## R.sup.1, R.sup.2, and R.sup.3 are each independently selected from one or more difunctional aromatic groups --O--Q.sup.1 --O--, --O--Q.sup.2 --O--, or --O--Q.sup.3 --O--, wherein Q.sup.1, Q.sup.2, and Q.sup.3 each independently contain 1-4 aromatic groups optionally connected by a direct bond, --CH.sub.2 --, C(CH.sub.3).sub.2, C(CF.sub.3).sub.2, --O--, --S--, ##STR18## C.dbd.O, --N.dbd.N--, --CH.dbd.CH--, --C.tbd.C--, --N(R.sup.12)--, wherein R.sup.12 is CH.sub.3 or CH.sub.3 CH.sub.2 --, and ##STR19## wherein the oxygen atoms are attached directly to the same or a different aromatic ring.
A process for producing a gas permeable crosslinked polyester glassy polymer as a membrane, which process comprises:
- (a) interfacially polymerizing:
- (i) an essentially monomeric aromatic group containing reactant having two or more alkali metal substituted phenoxy functional groups per reactant molecule in a mixture of water, a water soluble polar organic solvent, and a phase transfer agent, and
- (ii) an aromatic triacid trihalide selected from the group consisting of:
- ##STR30## an aromatic tetraacid tetrahalide selected from the group consisting of:
- ##STR31## wherein X is chloro or bromo, in one or more water insoluble nonpolar aprotic solvents at a temperature of between about 0.degree. and 90.degree. C. for between about 1 sec and 3 hr. in the presence of a phase transition catalyst, and
- (b) removing the crosslinked polyester glassy polymer membrane formed at the interface surface of the immiscible liquids formed in step (a);
- (c) quenching the crosslinked polyester glassy polymer membrane formed in step (b) in one or more organic solvents optionally in the presence of water at ambient conditions for between about 0.1 sec and 1 min;
- and
- (d) drying the crosslinked polyester glassy polymer of step (c) at ambient temperature at between about 14-20 hr or at about 50.degree.-120.degree. C.
Dependencies are inferred from the claim text.