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Samples of polyaromatic amines were synthesised by chemical and electrochemical methods, using different amounts of electrolytes for the purpose of doping the polymer. These polymers were found to show electrical conductivity in the range 10−12–10−6 S/cm. A study of conductivity at various temperatures indicates the semiconducting behaviour of these polymers. Thermal analysis shows that these polymers have high thermal stability.

Polyurethane (PU) elastomers from castor oil based polyol, polyethylene glycol (PEG) of various molecular weight (200, 400, and 600) and toluene diisocyanate were prepared in the form of transparent sheets. The sorption, mechanical and thermal properties have been studied. The solubility parameter, molecular weight between two crosslinks and degree of crosslinking of PU samples were calculated from equilibrium swelling experiments. The kinetic study of swelling revealed that sorption is anomalous in nature in all the samples. Diffusion coefficient (D) and sorption coefficient (S) were found to decrease with an increase in chain length of PEG. The stress-strain data showed that the elastomers obtained using PEG-200 gave the best mechanical properties. The thermal degradation of all elastomers starts at $ 250 C, regardless of the PEG chain length. The values of activation energy of degradation were in the range of 60À72 kJ=mole.

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Poly(2‐methoxycyanurate) of bisphenol F and bisphenol A (PMCBFA) was synthesized and fractionated by a fractional precipitation method. The fractions were characterized by viscometry, osmometry and gel permeation chromatography. The Mark–Houwink–Kuhn–Sakurada (MHKS) parameters were established in four solvents and at four different temperatures. The unperturbed dimensions and their coefficients in different solvents were computed using the Stockmayer–Fixman excluded volume theory. From the solution study it was found that PMCBFA is highly flexible. This may be due to the ether linkage present in the main chain.