## 3 Results  
Chemically diversified copolymers of DVB were synthesized via suspension polymerization. This method is especially suitable for the preparation of highly cross-linked, porous materials as regular microspheres having a diameter in the micrometric range. In the copolymer syntheses, various monomers that noticeably differed in chemical structure were used. We applied compounds that were both commercially available (St, DVB, VP, EGDMA) and synthesized in our laboratory (BMB, BMPS, BMPM). Figure 1 displays the chemical structure of all the used monomers. The assumed chemical structure of the obtained copolymers was confirmed by ATR-FTIR analysis (see Figure 2). The spectra of all copolymeric beads exhibited bands indicating the existence of a benzene ring, i.e., at 3058-3018 cm\({}^{-1}\) (\(\
u\) C-H), 1604-1602 cm\({}^{-1}\) and 1510-1492 cm\({}^{-1}\) (\(\
u\) C-C), 758 and 698 cm\({}^{-1}\) (\(\delta\) oop C-H of monosubstituted benzene), and 800-799 cm\({}^{-1}\) (\(\delta\) out-of-plane C-H of \(p\)-disubstituted benzene) and alkyl and alkylene groups, i.e., at 2962-2853 cm\({}^{-1}\) (\(\
u\) asym. and sym. C-H). The bands at 1452-1449 cm\({}^{-1}\) originated from the vibrations of alkyl and alkylene groups as well as from the benzene ring. In the case of NVP-_co_-DVB copolymer, the spectrum also showed a band at 1686 cm\({}^{-1}\) associated with the C=O stretching vibrations of the \(\gamma\)-lactam ring. On the other hand, for copolymers containing the ester groups, the carbonyl band could be seen at higher wave numbers (1747-1726 cm\({}^{-1}\)). The presence of the ester group was also manifested by the band at 1196-1087 cm\({}^{-1}\) (\(\
u\) C-O). A very low intense absorption band at 1638-1630 cm\({}^{-1}\) coming from the unreacted C=C double bonds was also visible in some spectra. The main drawback of the suspension polymerization is a broad-sized distribution of the obtained microspheres. Average size and size distribution depend on a number of factors including the diameter of the flask, the diameter of the stirrer, the volume ratio of the organic phase to the water phase, the mixing speed and the stabilizer concentration. While maintaining the constant value of the above-mentioned parameters, differences in  
Figure 1: Chemical structures of monomers used for the synthesis of copolymeric microspheres. Figure 2: ATR-FTIR spectra of copolymeric microspheres. (**a**); DVB-\(\alpha\)-BMB, DVB-\(\alpha\)-BMPS and DVB-\(\alpha\)-BMPM (**b**) DVB-\(\alpha\)-ST, DVB-\(\alpha\)-NVP and DVB-\(\alpha\)-EGDMA. the diameter of the synthesized microspheres were the result of the different chemical structure of the monomers. Because the monomers were chemically diversified, we dealt with different densities in the organic phase and, consequently, different interfacial tensions. As a result, microspheres of various diameters were created (Table 2). The mass median diameter of the synthesized microspheres was in the 54-155 \(\upmu\)m range. Microspheres with the smallest diameter were obtained for the DVB-\(co\)-ST copolymer. What is important, is that this copolymer also indicated a broad-sized distribution. As a consequence, the value of span was the highest among all tested copolymers. The remaining copolymers were more uniform. The smallest value of the width of the size distribution (0.470) was observed for the DVB-\(co\)-EGDMA microspheres. These considerable differences in size distribution are clearly visible in Figure 3. The microsphere diameters determined on the basis of SEM images for all of the investigated copolymers were in the range of about 8 to 200 \(\upmu\)m.  
The deliberate aim of this work was to synthesize microspheres having a highly developed internal structure. Generally, the porous structure of the polymers was predominantly determined by phase separation during polymerization.