# Tuning of Morphology and Surface Properties of Porous Silicones by Chemical Modification
## 2 Experimental Section  
### Materials and Methods  
All reagents and organic solvents were high purity and were used as received: poly(methylhydrogen)siloxane (PMHS) was obtained from Alfa Aesar; Karstedt catalyst, n-hexane, allytrimethylsilane (ATMS), and trimethylpropane tris(3-mercaptoethanol) (SHCL) were obtained from Sigma-Aldrich, St. Louis, MO, USA; and 2,2-dimethoxy-2-phenylacetophenone (DMPA) was obtained from Merck. Double-distilled water was used in all experiments.  
Poly(dimethyl-methylhydrogen)siloxane with 10 or 30% Si-H groups (CoSiH10 and CoSiH30) were synthesized according to [26]. A poly(dimethyl-methylvinyl)siloxane copolymer Vi50 with \(\sim\)50% vinyl groups was obtained by ring-opening copolymerization of octamethylcolotetrasiloxane (D\({}_{4}\)) and tetramethyltetravinylcytotetrasiloxane (V\({}_{4}\)) according to [27]. The surfactants were prepared as described previously [28].  
Fourier transform infrared (FT-IR) spectra were registered on a Bruker Vertex 70 Spectrometer in transmittance mode, in the 400-4000 cm \({}^{-1}\) spectral range, with a resolution of 4 cm\({}^{-1}\) and an accumulation of 32 scans.  
The contact angle was measured by taking digital photos of 10 \(\upmu\)L water droplets, following in principle the method described in [29]. Due to the irregular shape and porosity of the broken surfaces that were intended for analysis, attempts to use a goniometer were unsuccessful. Thus, manual adjustments of the sample position, repeated focusing of the camera, and multiple drop (at least 4 for each sample) analysis were carefully performed. The contact angles were measured with ImageJ free software and, alternatively, with the secant method applied manually on enlarged printed images. For each measurement, the average between the left and right CAs was taken, and an average of at least four drops on each sample is reported. Reference materials, like PDMS and glass slides, were measured and a reasonable precision within a few degrees was considered satisfactory for the purpose of our research.  
Surface tension and powder wetting measurements were performed with a Sigma 700 automated tensiometer from KSV. All samples were packed in the same way: 50 \(\pm\) 1 mg of roughly ground material was placed between two filter papers identically cut from the same batch and introduced into a specially designated metallic cylinder with a perforated bottom and a tightly closed piston. The experiments were performed in duplicate for each material, and the results were similar.  
SEM investigations were performed with a Quanta 200 microscope (FEI Company, Hillsboro, OR, USA), using an LFD (large field detector), working in low vacuum mode at 20 kV without any coating, and with a Verios G4 UC (Thermo Scientific, Waltham, MA, USA), using an ETD (Everhart-Thomley detector) at 5 kV, for more detailed observation. In the latter case, the samples were coated with 6 nm of platinum with a Leica EM ACE200 sputter coater to provide electrical conductivity and to prevent charge buildup during exposure to the electron beam. All the samples were analyzed in cross sections obtained by breaking the monolith materials.  
The compression tests were performed using an Instron 3365 two-column universal mechanical testing machine at a 50 mm/min compression rate. Monolith samples of 8 mm diameter were measured in triplicate, and the average value of the Young's modulus at 10% compression was considered.