## 2 Materials and Methods
### AFM Measurements  
AFM measurements were performed with DI3000 system (Digital Instruments, Santa Barbara, CA, USA) equipped with 100 \(\times\) 100 \(\upmu\)m X-Y scanner. Topography imaging was carried out in TappingMode using standard probes (Nanosensors Pointprobes: nominal tip radius \(\mathrm{r_{tip}}\) = 10 nm, resonance frequency \(\mathrm{f_{res}}\) = 306-353 kHz, and spring constant range k = 43-68 N\(\cdot\)m\({}^{-1}\)) under ambient conditions. The scanning area was 3 \(\times\) 3 \(\upmu\)m; typical scanning speed was approx. 1 \(\upmu\)m/s. The set of three topography data points was acquired for each sample in order to provide statistically significant data, as local morphological non-homogeneities could be noticed and excluded. The roughness values distribution allowed us to assume that the acquired data could be utilized for further analysis, providing expected consistency. In addition, 50 \(\times\) 50 \(\upmu\)m images were also acquired to confirm the homogeneity of the surface on a larger scale. The 3 \(\times\) 3 \(\upmu\)m scanning area allowed us to observe the presence of silver nanoparticles in the polymer film; therefore, the data obtained for this area was utilized in further analyses, while the nanoscale appearance of \begin{table} -  
* The mechanical property measurements from atomic force microscopy enabled the detection of the degradation of the outer layers of the material in terms of changes in stiffness and adhesion [23; 24; 25].
* Wettability tests provided complementary information to the roughness measurement concerning the practical aspects of the utilization of the film in particular conditions [25].
* Colorimetric analysis gave information concerning the loss of aesthetical aspects of the film as well as phenomena responsible for the aging process [26].  
\end{table} 
Table 1: The simulated solar radiation exposure parameters. \begin{table}
\begin{tabular}{l l} \hline \hline
**Basic Exposure Time** & **500 h** \\ \hline Type of lamp & evanescent \\ \hline Spraying of the samples & no spraying \\ \hline Black plate’s temperature & 37.1 \({}^{\circ}\)C \\ \hline Relative humidity during the exposure & 48\% (average value during the dry periods) \\ \hline The radiation intensity of full spectra of the xenon lamp (290 nm \(<\lambda<\) 800 nm) & 48\% (average value during the dry periods) \\ \hline The radiation intensity of UV spectra of the xenon lamp (290 nm \(<\lambda<\) 800 nm) & 48\% (average value during the dry periods) \\ \hline The radiation intensity of the xenon lamp & 0.34 \(\frac{W}{m^{2}\cdot mm}\) \\ \hline \hline \end{tabular}
\end{table} 
Table 2: The UV light exposure parameters. surface degradation can be noticed in the area of matrix-filler interphase. Images at both scales are shown in Figure 2.  
The mechanical properties of the film were determined using force spectroscopy, where contact probes NTMDT CSG30 (0.6 N\(\cdot\)m\({}^{-1}\), 6 nm radius) were used. In order to provide required measurement accuracy, the reference sample was utilized [27; 28]. Approach/retract speed was 10 nm/s. The maximum tip-sample force was limited to 75 nN in order to avoid sample's deformation and tip damage. The measurements were performed using following procedure: the force-distance acquisition was performed 10 times in a single spot; then, the probe's location was changed, and the acquisition procedure was repeated within an area of 3 \(\times\) 3 \(\upmu\)m. This process was continued while nine sets of curves were acquired. Then, in order to avoid the influence of local non-homogeneities, the measurement spot was changed three times, where the whole data collection procedure was performed. The topography data was processed using SPIP software (version 5.1.7) from Image Metrology [29], and force spectroscopy curves were analyzed while the DMT model was utilized. In both cases, median value was calculated and used in the analysis, and standard deviation was used to evaluate the uniformity and repeatability of the calculated values.