## 2 Materials and Methods
### Measurement Methods  
Structural characterization of the obtained materials was made on the basis of FTIR spectroscopy. For this purpose, a Bruker Tensor 27 FTIR spectrometer (Ettlingen, Germany) operating in the spectral range 4000-600 cm\({}^{-1}\) was used. The ATR-FTIR spectra were recorded with a resolution of 4 cm\({}^{-1}\). \begin{table}
\begin{tabular}{c c c c} \hline \hline \multirow{2}{*}{**Copolymer**} & \multirow{2}{*}{**Monomers**} & \multirow{2}{*}{**Monomers Ratio**} & \multicolumn{2}{c}{**Diluents (mL)**} \\ \cline{3-4}  & & & **Toluene** & **Chlorobenzene** \\ \hline BMA-co-EGDMA\_1\_T & \multirow{2}{*}{BMA} & EGDMA & 1:1 & 22.5 & - \\ BMA-co-EGDMA\_1\_C & \multirow{2}{*}{BMA} & EGDMA & 1:1 & & 22.5 \\ BMA-co-EGDMA\_4\_T & \multirow{2}{*}{BMA} & EGDMA & 1:4 & 22.5 & - \\ BMA-co-EGDMA\_4\_C & \multirow{2}{*}{BMA} & DVB & 1:1 & 22.5 & - \\ \cline{3-4} BMA-co-DVB\_1\_C & \multirow{2}{*}{BMA} & DVB & 1:1 & & 22.5 \\ BMA-co-DVB\_4\_T & \multirow{2}{*}{DVB} & DVB & 1:4 & 22.5 & - \\ BMA-co-DVB\_4\_C & \multirow{2}{*}{DVB} & DVB & 1:4 & & 22.5 \\ \cline{3-4} BMA-co-TRIM\_1\_T & \multirow{2}{*}{BMA} & TRIM & 1:1 & 22.5 & \\ BMA-co-TRIM\_1\_C & \multirow{2}{*}{TRIM} & TRIM & 1:1 & & 22.5 \\ BMA-co-TRIM\_4\_T & \multirow{2}{*}{TRIM} & TRIM & 1:4 & 22.5 & \\ BMA-co-TRIM\_4\_C & \multirow{2}{*}{TRIM} & TRIM & 1:4 & & 22.5 \\ \hline \hline \end{tabular}
\end{table} 
Table 1: The main experimental parameters of the microsphere synthesis. Figure 1: SEM image of BMA-co-TRIM_C microspheres synthesized in the presence of 0.5 wt.% (**a**) and 2.5 wt.% (**b**) of PVA. Porous structure of the investigated copolymers was ascertain based on the nitrogen amount adsorbed on the copolymers surface. The isotherms of nitrogen adsorption/desorption were collected at \(-196\)\({}^{\circ}\)C using ASAP 2405N analyzer (Micromerities Corp., Norcross, GA, USA). Before the porous structure measurements, the copolymers were outgassed (\(10^{-2}\) mm Hg) at 140 \({}^{\circ}\)C for 2 h. The linear Brunauer-Emmet-Teller (BET) plots were applied to calculate the specific surface area (\(S_{BET}\)). The pore volume (\(V\)) was evaluated based on a single point adsorption at a relative pressure \(p/po=0.985\). Pore size distributions (PSD) and its maxima (PSD\({}_{\rm max}\)) was appraised according to the Barrett, Joyner and Halenda (BJH) approach [60]. The pore diameters (\(D_{BJH}\)) were evaluated on the basis of the PSD\({}_{\rm max}\). A scanning electron microscope (SEM) Duall BeamTM, Quanta3D FEG (Fei Company, Hillsboro, OR, USA) was used for taking the images of the obtained microspheres. Their size and size distribution were measured by a Mastersizer Analyser 2000 (Malvern, Instruments Ltd., Worcestershire, UK). The British standard BS2955:1993 was the base for calculation of the distribution statistics. According to the standard, \(D\)(0.1) is the particle size below which 10% of the sample lies, whereas \(D\)(0.9) is the particle size below which 90% of the sample lies. \(D\)(0.5) refers to Mass Median Diameters (MMD) that is the size at which 50% of the sample is smaller and 50% is larger. All of the particle diameters are given in microns. Span (width of the size distribution) was calculated on the basis of the following formula:  
\[span=\frac{D(0.9)-D(0.1)}{D(0.5)} \tag{1}\]  
Thermogravimetric (TG) analyses were performed using a Netzsch STA 449 F1 Jupiter thermal analyzer (Selb, Germany) both in helium as well as synthetic air atmosphere (flow = 20 mL/min). The analysis temperature range was 35-800 \({}^{\circ}\)C whereas the heating rate was 10 \({}^{\circ}\)C min\({}^{-1}\). The measurements were performed in Al\({}_{2}\)O\({}_{3}\) crucibles. As a reference, an empty Al\({}_{2}\)O\({}_{3}\) (mass of \(\sim\)160 mg) crucible was used. The sample masses were about 10 mg. On the basis of the TG curves, the characteristic temperatures of \(T_{5\%}\), \(T_{20\%}\), \(T_{50\%}\) mass losses as well as final decomposition temperature (_FDT_) were determined.