## 2 Materials and Methods
### Measurement Methods  
Attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectra were obtained with a Bruker Tensor 27 FTIR spectrometer (Ettlingen, Germany). The FTIR spectra were recorded in the 4000-600 cm\({}^{-1}\) spectral range with 32 scans per spectrum at a resolution of 4 cm\({}^{-1}\). The textural characterization of the investigated samples was determined on the basis of the low-temperature nitrogen adsorption/desorption method. Nitrogen adsorption/desorption isotherms at \(-196\)\({}^{\circ}\)C were determined volumetrically using ASAP 2405N analyzer (Micromerities Corp., Norcross, GA, USA). The measurements of the porous structure of the copolymers were preceded by outgassing (10\({}^{-2}\) mm Hg) of the samples at 140 \({}^{\circ}\)C for 2 h. To calculate the main parameters of the porous structure the Brunauer-Emmet-Teller (BET) method was applied. The linear BET plots were used to evaluate the specific surface area (\(S_{BET}\)). The total pore volume (\(V\)) was estimated from a single point adsorption at a relative pressure \(p/po\) = 0.985. The calculations of pore size distributions (PSD) followed the Barrett, Joyner and Halenda (BJH) procedure [56]. The pore diameters (D\({}_{BJH}\)) were estimated from the PSD maxima. The microspheres were imaged using a scanning electron microscope (SEM) Duall Beam\({}^{\mathrm{TM}}\), Quanta3D FEG (Fei Company, Hillsboro, OR, USA) whereas the analysis of the size and distribution of the microspheres was made using Mastersized Analyser 2000 (Malvern, Instruments Ltd., Worcestershire, UK). The statistic of the distribution was calculated using the derived diameters in accordance with British standard BS2955:1993. According to this standard, \(D(0.1)\) is the size in microns of particle below which 10% of the sample lies; \(D(0.9)\) is the size of the particle below which 90% of the sample lies. \(D(0.5)\) refers to Mass Median Diameters (MMD), which is the size in microns at which 50% of the sample is smaller and 50% is larger. Span (the width of the size distribution) was calculated as  
\[span=\frac{D(0.9)-D(0.1)}{D(0.5)} \tag{1}\]  
Thermograviometry (TG) and differential scanning calorimetry (DSC) were performed with a Netzsch STA 449 F1 Jupiter thermal analyzer (Germany) in the range of 30 to 750 \({}^{\circ}\)C in helium or synthetic air (flow = 20 mL/min), at the heating rate of 10 \({}^{\circ}\)C min\({}^{-1}\). All measurements were done in Al\({}_{2}\)O\({}_{3}\) crucibles (mass of \(\sim\)160 mg). As a reference, an empty Al\({}_{2}\)O\({}_{3}\) crucible was applied. Sample masses of \(\sim\)10 mg were used. From the TG curves the temperatures of 5 (\(T_{5\%}\)), 20 (\(T_{20\%}\)) and 50% (\(T_{50\%}\)) mass losses were determined. In turn, the temperature at which the maximum rate of mass loss (\(T_{\mathrm{max}}\)) for particular decomposition stages occurred was designed on the basis of differential TG (DTG) curves. The composition of the gas that evolved during the decomposition process was analyzed by a Bruker Tensor 27 FTIR spectrometer (Germany) coupled online to a Netzsch STA instrument by the Teflon transfer line with a 2 mm diameter heated to 200 \({}^{\circ}\)C. The FTIR spectra were recorded in the 600-4000 cm\({}^{-1}\) spectral range with 16 scans per spectrum at 4 cm\({}^{-1}\) resolution. In order to obtain more detailed DSC data, the measurements were additionally carried out with a Netzsch 204 calorimeter (Selb, Germany) operating in a linear programmed mode. The measurements were conducted at a constant heating rate (10 \({}^{\circ}\)C/min) from