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The paper presents the small angle X-ray scattering (SAXS) studies of series of controlled porosity glasses (CPGs) with a polymer layer deposited on their surface which was obtained by crosslinking a dextran- polyimine mixture. For the investigated systems the power law scattering conditions (I(q)=I(subscript 0)q(superscript -(alpha) ), where I(subscript 0) and (alpha) are the constants, q- scattering vector) are fulfilled in a broad range of q values. The (alpha) value in the range 4<(alpha) <6 can result from the diffuse profile of the electron density in the boundary layer (transition layer) existing between the regions of different electron densities. For the investigated samples the values of (alpha) exponent change according to amounts of polymer in samples on the range 3.97- 4.49. Thus, the thickness of the transition layer for samples with (alpha) greater than 4.0 was calculated. The correlation between the amount of dextran or polyimine or crosslinking agent (diethyleneglycol diglycidyl ether) and the thickness of the transition layer was observed. Also, the comparison of the surface areas of CPGs with surface polymer layer measured by means of SAXS and BET method was examined. The obtained results demonstrate that the use of the equation [J(q)=k(subscript 1)/q + k(subscript 2)/q$=3)] in SAXS calculations results in SAXS surface areas comparable with those from BET measurements. In addition, the differences between them depend on the transition layer surface also explains the distinctions between the ion capacity of sorbents and the concentration of electron - donor nitrogen atoms existing in the investigated materials.
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