Exceptionally high molecular weight polydimethylsiloxane elastomers were formed via step-growth polymerization of heterobifunctional siloxane macromonomers.1
These materials exhibited elastomeric behavior with no chemical crosslinking observable from advanced NMR, DSC, and rheological studies. Reinforcing the silicone elastomer with surface-passivated silica produced nanocomposites with tensile strengths up to 10 MPa and elongations approaching 5000% with good shape recovery.2
These ultra-high elongation silicone elastomers can be processed similar to conventional two-component platinum cure silicone RTVs. The synthesis and characterization of the siloxane macromonomers will be presented, as well as the mechanical and physical properties of the nanocomposites compared to conventional silicone elastomers.
1. J. Goff, S. Sulaiman, B. Arkles, J. Lewicki, Adv. Mater. 2016, 28, 2393-2398.
2. Arkles, B.; Goff, J.; Sulaiman, S. In Proceedings of the 188th Technical Meeting, Rubber Division, American Chemical Society, Cleveland, OH, October 12-15, 2015, Paper # 124.