Analytical model of equation of state for polydisperse fluid of adhesive spherical particles

An analytical model of the equation of state is presented for the polydisperse fluid of adhesive colloidal particles. The model is based on the mean-spherical approximation solution of the Ornstein-Zernike equation for a multicomponent hard sphere Yukawa fluid in which the Yukawa tails are sufficiently short range and strong. In particular, assuming that distributions of diameters and ‘charges’ of particles are described by the Schulz function, the analytical expressions for the compressibility and the pressure for the intrinsically polydisperse fluid are given in terms of simple functions of the packing fraction, the adhesion parameter and the Schulz distribution parameter.     

Ring‐opening polymerization of lipoic acid and characterization of the polymer

Thermal polymerization of DL ‐α‐lipoic acid (LPA) in bulk without any initiator proceeded easily above the melting point of LPA. The molecular weight polymer determined by GPC was high. From the ¹H NMR spectra of polymers, poly(LPA) obtained from polymerization of high purity LPA was to consist of cyclic structures, which was confirmed by ESI‐MS. Interlocked polymer consisting of poly(LPA) and dibenzo‐30‐crown‐10 entangled with each other was synthesized by the polymerization of LPA in the presence of dibenzo‐30‐crown‐10. From the DSC analysis of the polymers, glass transition temperature was estimated to be about ?11 °C, but melting point was not observed, indicating that poly(LPA) is an amorphous polymer. By photodecomposition of poly(LPA), M_n was rapidly decreased at the early stage of the decomposition. After that, the M_n of the polymer kept and then was almost constant even for a prolonged reaction time. On the basis of the results, it would be presumed that poly (LPA) obtained form polymerization of high purity LPA includes an interlocked structure. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2010