Two routes have been developed inorder to prepare an inclusion complex of polyaniline (PANI) and β‐cyclodextrin (βCyD). The first route was to in situ polymerize N‐phenyl‐1,4‐phenylenediamine (PPD) which was encapsulated in βCyD in advance. The formation of an inclusion complex was confirmed by UV‐vis, circular dichroism (CD), and NMR spectra. It was found that the synthesized complex was readily dissolved in a range of solvents due to the solubility of βCyD. In these solvents, PANI was well encapsulated by βCyD with some conformation change in the chain of PANI, which was proved by the CD spectra of PANI. The second route involved preparing the inclusion complex by post‐encapsulation of PANI emeraldine base (EB) into βCyD in aqueous solution at room temperature. The encapsulation of EB into βCyD was confirmed by FT‐IR and UV‐vis spectra. The band shift in UV‐vis spectra indicated that the inclusion complexation was a gradual process, and the change in the chain conformation of PANI was also observed after it was encapsulated into βCyD. Copyright © 2003 John Wiley & Sons, Ltd.

The dispersion of styrene monomer (StM) in an aqueous solution of a poly(vinyl alcohol) (PVA) stabilizer has been studied experimentally. Parameters affecting the initial StM dispersion, such as stirring time, type and concentration of the suspending agent, and the volume fraction of styrene, have been studied in detail and the results compared with existing theories. The transitional time for a dynamic equilibrium to be established in the dispersions was found to be 150 min. When the molecular weight of the PVA increases, the drop size decreases and the StM drops become more stable toward coalescence. With one of the PVAs (PVA-2), the critical PVA concentration, for a constant drop size, was found to be equal to 0.013%, 0.023%, and 0.043% respectively, when the volume fraction of StM correspondingly equaled 0.05, 0.1, and 0.2.

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The effective microbial production of copolyesters of 3‐hydroxybutyrate (3HB) and 4‐hydroxybutyrate (4HB) with high mole fractions of 4HB units by a wild‐type strain of Ralstonia eutropha H16 was investigated in culture solutions containing 4‐hydroxybutyric acid (4HBA) and various carbon substrates in the presence of a nitrogen source such as ammonium sulfate. The addition of glucose or acetic acid to the culture solution containing 4HBA in the presence of ammonium sulfate resulted in the production of random copolymers of P(3HB‐co‐4HB) with compositions of up to 82 mol% 4HB, but the yield of copolymers was less than 7 wt% of dried cell weights. In contrast, when n‐alkanoic acids such as propionic acid, butyric acid, valeric acid and hexanoic acid, being subject to β‐oxidation metabolism in the cell, were used as the co‐substrates of 4HBA in the presence of ammonium sulfate, a mixture of copolymers with two different 4HB compositions was produced, and copolyesters with compositions of 93–100 mol% 4HB were isolated from chloroform–n‐hexane insoluble fractions in the mixture of copolymers. Especially, when this wild‐type Ralstonia eutropha H16 was cultivated in a medium containing 4HBA (15 g litre−1), propionic acid (5 g litre−1) and ammonium sulfate (5 g litre−1), namely C/N (mol/mol) = 10, the P(4HB) homopolymer was produced at maximally 34 wt% of dry cell weight (7.8 g litre−1), and the conversion yield of 4HBA to P(4HB) homopolymer resulted in values as high as 21 mol%. © 1999 Society of Chemical Industry

An optically active copolyaniline, poly(aniline-co-o-toluidine), which forms a different helix structure from that of the corresponding homopolymers was obtained by chemically oxidative polymerization with (1S)-(+)-10-camphorsulfonic acid as the chiral inductor in organic media. Formation of the genuine copolymer rather than a mixture of the corresponding homopolymers was confirmed by cyclic voltammogram, UV/vis, and circular dichroism spectra. The circular dichroism spectra of polyaniline and poly(aniline-co-o-toluidine) at suitable copolymer composition when dissolved in the same organic solvents revealed that their helical windings induced by the same chiral acid are reversed to each other. It is very interesting that the helical conformation of polyaniline can be inverted by inserting o-toluidine units into the polymer main chain. Since the chirality of poly(aniline-co-o-toluidine) depends on the o-toluidine content, this stereo-controlled polymerization of aniline derivatives affords a method to tailormake electrically conductive materials with specific electrochemical and chiroptical properties. As a proof of concept, extension of this approach to other optically active polymers will be also expected.