Solution thermodynamics of PEG samples in aqueous and nonaqueous (methanol, chloroform, tetrahydrofuran, and dimethylsulfoxide) solutions have been investigated by viscometric studies at 25, 30, 35, and 40 C. The hydrodynamic expansion factor, a h , and the unperturbed root mean square end-to-end distance, hr 2 i 1=2 h , found for the system indicated that the polymer coils contract as the temperature is raised. The long-range interaction parameter, B, was also evaluated and a significant decrease with increasing temperature was observed. The theta temperatures, y, obtained from the temperature dependence of (1/2 À v) and the second virial coefficient, A 2 , are quite good in agreement with the calculated val-ues evaluated via extrapolation and interpolation methods. The thermodynamic interaction parameter, v, was evaluated through the sum of the individual values of enthalpy and entropy dilution parameters for PEG samples. The restrictions applying to the establishment of concentration regimes, short-range, and long-range interactions are discussed. A parallelism is found between solubility profiles obtained by solution viscometry and solubility parameter approaches for PEG/solvent systems.

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Poly(m-aminophenol) (PMAP) and poly(m-aminophenol)-succinat compound (PMAP-Suc) containing ester bridge were synthesized in this study. PMAP were synthesized by chemical oxidative polymerization of m-aminophenol (MAP) in HCl medium with ammonium peroxydisulphate (APS) as an initiator at different temperatures. The optimum polymerization conditions (temperature: 25°C, reaction time: 4 h, normalized MAP/APS ratio, k: 0.625 and mol of MAP/mol of APS, r: 0.5) of PMAP were determined. PMAP was esterified in N-methyl pyrrolidone by using solution of succinic acid as cross-linking agent and concentrated sulphuric acid as catalyst under appropriate ambient conditions. The general scheme of esterification and cross-linking reaction for PMAP is proposed. These reactions were also evidenced by spectroscopic, thermal and surface morphology as well as structural characteristics relationship of macromolecules. The structures of PMAP and PMAP-Suc were characterized by solubility test, FTIR, 1 H NMR and 13 C NMR, UV-vis spectroscopy, thermal (TGA-DTA) and SEM analyses.

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