Technical Universlty B mV e s h k a 230,637 1 1 Bmo Czech RepublicThis paper reviews the various reactions used to sulfonate polymers, especially polystyrene. The mechanisms for the sulfonation of low molar mass compounds are also 13scussed. The commonly used sulfonation reagents are described, with an emphasis on SO, and its physical and chemical properties. Polymer sulfonations can be grouped into two general routes: one involving homogeneous sulfonation and t h e other heterogeneous reactions.

Kinetics of the heterogeneous sulfonation of polystyrene (PS) beads using gaseous SO3 was investigated. Scanning electron microscopy (SEM) and electron diffraction scattering spectroscopy (EDS) was employed to study the kinetics of diffusion of SO3 into the PS particles. The diffusion of SO3 through the barrier of sulfonated polystyrene (SPS) on the beads surface was the primary parameter determining the rate and the yield of the sulfonation reaction. The measurement of the time dependence of the thickness of sulfonated layer formed on the solid PS surface provided for the hypothesis that the sulfonation in heterogeneous phase was diffusion controlled. Diffusion coefficients of SO3 in PS at −5°C, 22°C, and at 50°C and activation energy of SO3 diffusion to the solid PS were determined from these experimental data assuming in the first approximation a simple diffusion unaffected by the ongoing sulfonation reaction. The experimental data were fitted using Johanson‐Mehl‐Avrami‐Jerofyeev‐Kolgomorov's equation to obtain an overall rate constant of heterogeneous sulfonation on solid PS surface. POLYM. ENG. SCI., 2009. © 2009 Society of Plastics Engineers

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In proposed study the effect of the composition and structure of polyurethane/ground rubber (PUR/GR) composites on the mechanical behavior was evaluated. The structure-properties relationship was studied for PUR matrices with different polarity, porosity and mechanical properties. The morphology of PUR/GR composites was expressed by two structural parameters-interspace filling and interspace volume. Experimental data of mechanical testing were fitted by powerlaw functions containing mentioned structural parameters whereas exponents of these parameters reflect differences in mechanical properties and chemical composition of PUR matrices. Obtained equations describe the mechanical behavior with respect to the structure and morphology of porous PUR/GR composites consisting of one filler and different PUR matrices. Proposed study suggests new approach to the description of the relationship between mechanical behavior and structure of porous composite materials.