The enhancement of chain rigidity and gas transport performance of polymers of intrinsic microporosity via intramolecular locking of the spiro-carbon.

Here, we present a new strategy to improve the rigidity of through the introduction of 8-membered ring locking into the flexible spiro-carbon pivot point to produce an interlocked polycyclic structure. This locked version of shows simultaneous increases in both permeability and selectivity that place it well above the Robeson upper bound for a number of important gas pairs. Molecular modelling demonstrates that the locked version of is much more rigid.

Copolymers of Intrinsic Microporosity Based on 2,2',3,3'-Tetrahydroxy-1,1'-dinaphthyl.

A series of new copolymers with high molecular weight and low polydispersity, prepared from tetrahydroxydinaphthyl, tetrahydroxyspirobisindane, and tetrafluoroterephthalonitrile monomers, prevent efficient space packing of the stiff polymer chains and consequently show intrinsic microporosity. One copolymer, DNPIM-33, has an excellent combination of properties with good film-forming characteristics and gas transport performance, and exhibits higher selectivity than the corresponding spirobisindane-based homopolymer PIM-1 for gas pairs, such as O(2) /N(2) , with a corresponding small decrease in permeability. This work demonstrates that significant improvements in properties may be obtained through development of copolymers with intrinsic microporosity (CoPIMs) that extends the spectrum of high-molecular-weight ladder structures of poly(dibenzodioxane)s.

Cloud point extraction: an alternative to traditional liquid-liquid extraction for lanthanides(III) separation.

Cloud point extraction (CPE) was used to extract and separate lanthanum(III) and gadolinium(III) nitrate from an aqueous solution. The methodology used is based on the formation of lanthanide(III)-8-hydroxyquinoline (8-HQ) complexes soluble in a micellar phase of non-ionic surfactant. The lanthanide(III) complexes are then extracted into the surfactant-rich phase at a temperature above the cloud point temperature (CPT).