S1.3. Fabrication of HBPSi-R/EP co-polymer systems
The fabrication of HBPSi-R/EP co-polymer systems employed a facile thermosetting workflow via casting methods. The resin matrix included a bisphenol-A diglycidyl ether epoxy resin (DGEBA, E51) and an anhydride-type curing agent (Methyl tetrahydrophthalic anhydride, MTHPA). A drop of tertiary amine (Tris(dimethylaminomethyl)phenol, DMP-30) was used as the curing accelerator. Firstly, 70 g of DGEBA with different mass fraction of HBPSi-R (3%, 6%, 9%) was pre-polymerized at 80 °C for 15 min. Since a uniform resin solution of xHBPSi-R/EP was obtained, where x is the mass fraction of HBPSi-R. 56 g of MTHPA and a drop of DMP-30 were added and stirred for another 15 min. The pre-polymer mixture was fully degassed in an 80 oC vacuum for 30 min and then poured into a pre-heated mold. The curing process underwent a heating procedure of 120 °C × 2h, 150 °C × 3h and 180 °C × 2h, and then demolding and tailoring for test.