Thermogravimetry, diffuse reflectance infrared
Fourier transform spectroscopy, and X-ray photoelectron
spectroscopy (XPS) were used for the studying of ther-
mally induced structural changes of polyacrylonitrile
(PAN) deposited on the surface of SBA-15 type meso-
porous silica. Polymer was introduced onto the support by
the precipitation polymerization of acrylonitrile in aqueous
suspension of SBA-15. Low temperature transformation (to
723 K) of the deposited PAN was analyzed. It was found
that at about 523 K, exothermic cyclization of polymer
chains to the so-called ladder form of PAN occurred.
However, the total cyclization of PAN required higher
carbonization temperatures, at which gradual dehydroge-
nation followed by graphitization was initiated. XPS
revealed that the cyclic form of PAN and a relatively large
amount of carbonyl species, formed during the carboniza-
tion of the PAN/SBA-15 composite at 623 K, were
responsible for the high sorption capacity in the methyl–
ethyl ketone (MEK) vapor elimination. The efficiency in
the MEK adsorption was also influenced by the content of
PAN-derived carbon deposited on the SBA-15 surface