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a-Cyclodextrin membranes were prepared by the phase inversion method using four types of casting solvents such as N-methyl pyrrolidone (NMP), dimethyl sulfoxide (DMSO), dimethyl acetamide (DMAc), and dimethyl formamide (DMF) herein-after termed as a-CD-NMP, a-CD-DMSO, a-CD-DMAc, and a-CD-DMF, respectively. The membranes were characterized by IR, XRD, TGA-DTA, DSC, and SEM analysis and show that solvents like NMP, DMA, DMF give good uniform morphological membranes and are better than that of DMSO. Thermal decompositions of the pure polymer and composite membranes indicate different range of thermal degradation of the membrane. This study reveals that the casting solvents NMP, DMF, DMAC have nearly same significant effect on morphology and other properties of the membranes. This is explained in terms of demixing behavior of the polymer and the combined effect of solvent volatility and polymer-solvent interactions as estimated from Hansen solubility parameter. Solvent hydrophobicity also affects the performance of the membrane and can be determined in terms of water permeability.

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A Chiral polymer from 1,2-bis(2-methyl-1-triethylsiloxy-1-propenyloxy)ethane and dialdehyde from adipoyl chloride and 4-hydroxy benzaldehyde has been prepared in gram scale level and characterized by IR, NMR, TGA, DSC, optical rotation and Circular dichrosm (CD) study. The same was used for preparation of enantioselective membrane by phase inversion technique and the membrane was characterized for pore size and surface morphology through SEM (Scanning Electron Microscope) analysis. The enantioselective property of the membrane in the resolution of racemic compounds was studied using aqueous solution of Atenolol, Captopril, Propranolol hydrochloride and Salbutamol as feed solution. Pressure driven membrane processes were studied under pressure 4:84 Â 10 À2 N/m 2 , 24:22 Â 10 À2 N/m 2 and 48:44 Â 10 À2 N/m 2 . The Effect of feed concentration and operating pressure on membrane performance were studied differently. Solution diffusion model have been used to explain the permeation behaviour of the membrane. From this type of membrane 95% ee and 6.4 mg/m 2 h of flux were obtained.KEY WORDS: Atenolol / Captopril / Propranolol Hydrochloride / Salbutamol / Enantioselective Membrane / Chiral polymers are important in various applications, including the separation of racemic compounds and polymeric catalysis in asymmetric synthesis.1 Although various methods have been developed to synthesize chiral polymers, we focus on repetitive asymmetric reaction between prochiral monomers using a chiral catalyst. Asymmetric polymerization by means of repetitive asymmetric C-C bond forming reactions in the presence of a chiral catalyst gives optically active polymers having main chain configurational chirality. Novel optically active polymers have been prepared by asymmetric polymerization methods based on asymmetric reactions, such as asymmetric Diels-Alder reaction, asymmetric addition of allylsilane to aldehyde and asymmetric Mukaiyama aldol reaction.1 These asymmetric reactions are used for chiral polymer synthesis by repetitive asymmetric reaction between prochiral monomers to give optically active polymers. Recent progress in the method of asymmetric synthesis prompted us to design new chiral polymers by repetitive asymmetric reaction. This type of polymerization is attracting attention as one of the efficient methods for accessing optically active polymers.The Mukaiyama aldol reaction is an important C-C bond forming reaction. Based on this reaction, a number of complicated molecules, including naturally occurring compounds have been skillfully synthesized. In polymer synthesis, this type of reaction has been used as a new polymerization method called 'aldol group transfer polymerization' (aldol-GTP). All of the dialdehyde monomer used in asymmetric polymerization are useful for the aldol polymerization. Various catalytic asymmetric Mukaiyama aldol reactions of silyl enol ethers and aldehydes have been studied using chiral catalyst.

The membranes containing facilitated transport groups for Carbon dioxide had been prepared by immobilizing PAMAM ( Polyamidoamine) (Generations 0,1,2,3,4) dendrimer into the polymeric membranes. The dendrimer incorporated membranes were prepared by the phase inversion method. The permeation abilities of the membranes for pure CO 2 and binary mixture of CO 2 /N 2 were calculated. The effects of feed gas pressure on the permeability of the membranes were studied. The results of the permeation experiments showed that PAMAM dendrimer (Generation 4) composite membrane possessed a better CO 2 permeability and selectivity over N 2 than the any other membranes composite with other generations of dendrimer (Generations 0,1,2,3).