Polysulfone has been carboxylated, via a metalated intermediate, by reaction of a THF solution of polymer with n‐butyllithium and then treatment with carbon dioxide. The polymer reactions with n‐butyllithium were close to quantitative and did not require the use of a tertiary amine catalyst. A series of polymers ranging from 0.2 to 1.9 carboxyl groups per repeat unit was prepared by this method in the salt, acid and ester form. The structures of these polymer derivatives were characterized by 1H‐NMR, 13C‐NMR and IR. The glass transition temperatures and thermal stabilities were characterized by differential scanning calorimetry (DSC) and thermogravimetry (TG).

Carboxylated polysulfone membranes having a chiral recognition site induced by an alternative molecular imprinting technique Yoshikawa, M.; Izumi, J-I; Ooi, T.; Guiver, Michael; Robertson, Gilles Polymer Bulletin 40, 517-524 (1998) SUMMARYMolecularly imprinted polymeric membranes were prepared from carboxylated polysulfone. Membranes imprinted by Z-D-Glu recognize the D-isomer in preference to the corresponding L-isomer, and vice versa. The amino acid preferentially adsorbed by the membrane was also selectively permeated by electrodialysis. INTRODUCTIONWe have reported that optical resolution of racemic α-amino acids was attained by molecularly imprinted polymeric membranes, which were prepared from polystyrene resins bearing oligopeptide (1-4) or derivatives of natural polymer (5). The molecular imprinting technique, first proposed by Wulff (6), is a facile one for introducing molecular recognition sites into polymeric materials (7-9).We have applied an alternative molecular imprinting technique to our studies (1-5) that is based on inducing "molecular memory" in a membrane substrate at the same time of gelation. An optically active imprint molecule is combined with the membrane polymer containing a functional group moiety in solution. The membrane polymer assumes a favourable conformation for the functional group to interact with the imprint molecule. Upon gelation and membrane formation, a "molecular memory" of the optical isomer is retained by the formed membrane, such that it recognizes or favours interaction with isomers of the same configuration. The present work concerns the formation of molecularly imprinted polymeric membranes obtained from an entirely non-chiral synthetic polymer having carboxyl groups. The chiral recognition ability of these imprinted polymeric membranes derived from carboxylated polysulfone was investigated.

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The development of polymeric anion‐exchange membranes (AEMs) combining high ion conductivity and long‐term stability is a major challenge for materials chemistry. AEMs with regularly distributed fixed cationic groups, based on the formation of microporous polymers containing the V‐shape rigid Tröger's base units, are reported for the first time. Despite their simple preparation, which involves only two synthetic steps using commercially available precursors, the polymers provide AEMs with exceptional hydroxide conductivity at relatively low ion‐exchange capacity, as well as a high swelling resistance and chemical stability. An unprecedented hydroxide conductivity of 164.4 mS cm−1 is obtained at a relatively a low ion‐exchange capacity of 0.82 mmol g−1 under optimal operating conditions. The exceptional anion conductivity appears related to the intrinsic microporosity of the charged polymer matrix, which facilitates rapid anion transport.