## 3 Results and Discussion
### Morphology of Studied Polymers  
One of the methods for assessing the shape and size of microspheres is optical microscopy. Images taken for the studied materials are shown in Figure 5. The left column of the figure contains the photos of polymers prepared with toluene as a pore-forming agent, while those in right column are for the series prepared with the mixture of alcohols. Figure 4: DTG curves recorded under helium and synthetic air conditions. DTG curves of the toluene series in He (**a**) and in the air (**b**), and the mixture of alcohols series in He (**c**) and in the air (**d**). Figure 5: Images of the synthesized polymers taken using an optical microscope. Magnification 10\(\times\). All synthesized materials possess regular spherical shapes. In the series prepared with toluene, large particles dominate, but their size decreases with increasing GMA content in the polymers. Most of the pDVB t microbeads have diameters of 100-160 \(\upmu\)m, while in the case of DVB-GMA 1:2 t, the largest ones have diameters of only 100 \(\upmu\)m. Polymers synthesized using mixture of decanol and benzyl alcohols are in all cases smaller than those in previous series. Even pDVB db diameters do not exceed 100 \(\upmu\)m. The subsequent materials containing higher GMA content are increasingly finer. The largest particles of DVB-GMA 1:1 db and DVB-GMA 1:2 db are ca. 50 \(\upmu\)m in diameter. In the latter material, conglomerates are formed by particles agglomerating together. Taking into account that all the polymers were prepared according to the same procedure, it can be concluded that both the chemical composition of the polymers and the used pore-forming solvents influence the size of resulting particles. The porous structure of the prepared polymers was determined by the low temperature nitrogen adsorption-desorption method. The obtained results of the measurements are presented in Table 5.  
The largest specific areas and the greatest values of total pore volumes were received for pDVB, while the poorest development of porosity was observed for the DVB-GMA 1:2 copolymers possessing the least contents of crosslinking monomer (DVB). This finding is in good agreement with the literature reports [20; 21; 22]. DVB, with two vinyl groups, is able to form connections between adjacent polymer chains. As its amount in the polymer compositions increases, the cross-linking density of the polymeric network increases, which results in the better development of porosity. Consequently, a decrease in specific surface area can be observed in both tested series with a decrease in the cross-linking monomer content. Additionally, an influence of porogen solvents is also visible. Larger S\({}_{\text{BET}}\) were obtained for series with toluene. In the case of the DVB-GMA db series, fewer cross-linked copolymers (1:1 and 1:2) were nonporous. Mean pore widths of the polymers prepared with toluene as the porogenic diluent are within the range of 5.0-11.6 nm, while those synthesized with the use of the mixture of the alcohols have almost twice higher values. More detailed data on porosity are provided by the pore size distribution analysis (Figure 6). In the series of the polymers prepared with toluene as a porogenic solvent (Figure 6a), the maximum for pore size distribution is in the width range of 10-30 nm. Above this range, the pore volumes gradually decrease. The influence of pore-forming solvent(s) on the pore size distribution of pDVB is depicted in Figure 6b. The initial parts of the PSD profiles are quite similar, but above the width of 150 nm, pDVB t has very few pores, while pDVB db has a well-developed macroporous structure. This difference is a consequence of the chemical nature of solvents used as porogens. Toluene, as a thermodynamically good solvent for the polymer, promotes the formation of mesopores, while the mixture of alcohols with poorer solving properties favors the creation of macropores and, to a lesser extent, mesopores [24; 25; 29; 30].