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This work presents a new approach to the investigation of mass transport processes in polymers. The coefficient of water diffusion in polyacrilonitrile was measured using fiber optic evanescent wave spectroscopy (FEWS). Unclad AgClBr fibers of 0.9 mm diameter were dip‐coated by PAN layers of 1–10 µm thickness. The transmission of the fibers in the mid‐IR was measured using a Fourier transform infrared (FTIR) spectrometer. The penetration of water into these layers gave rise to significant changes in the measured spectrum. These changes were used for diffusion studies in situ. The novel statistical approach to the analysis of spectra was developed for the purpose of calculating the diffusion coefficient, D, using spectral data. This analysis reveals the specific wavelengths which have been taken into account for the calculation of D. The FEWS procedure, combined with statistical treatment of the spectral data, offers a high accuracy in the calculation of parameters of diffusion. It must be emphasized that the cylindrical symmetry of our fibers renders them especially suitable for the diffusion study and allows us to obviate the difficulties caused by end effects. Copyright © 2003 John Wiley & Sons, Ltd.

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This work presents the novel binary and ternary composite materials, based on a low-density polyethylene, metal alloy, which have a melting point close to those of polyethylene and carbon black. Oriented structures were obtained when high-viscosity polyethylene was used as a matrix material. Resistivity of the composite was investigated and nonohmic behavior of the ternary composites was revealed. Temperature dependence of the thermal capacity was studied. The IR (infrared) spectra of the composites were studied using an FTIR (Fourier-transform infrared) spectrophotometer. The presence of the alloy caused intensive oxidation of carbon black in the ternary composites as well.