Development of New Thermal Protection Systems Based on Silica/Polysiloxane Composites: Properties Characterization II
This research is the second installment of an effort to characterize a new ablative material through a collaboration between The University of Texas at Austin and Dyna-Glas, LLC. The DG-UHTR polysiloxane resin system manufactured by Dyna-Glas, based on a blend of polysiloxane chemistries, was compared to SC-1008 phenolic resin and evaluated in terms of combustion, flammability, and ablation properties. DG-UHTR was used to fabricate silica fiber-reinforced composite materials by compression molding of prepreg. The silica/DG-UHTR was compared to silica/phenolic fiber-reinforced polymers (FRPs) made in our lab as well as silica/phenolic prepreg purchased commercially. The neat DG-UHTR polysiloxane resin showed a high char yield at 86.5% than the neat SC-1008 resin at 55.4%. Composites made from the DG-UHTR resin showed exceptionally high char yields of 97.5%, 96.7%, and 95.8% for 35wt%, 40wt%, and 48wt% samples. The composites showed superior recession rate, peak heat soak temperature, mass loss rate, and mass loss percent during ablation testing using an oxy-acetylene test bed (OTB).
Author: Kurt Schellhase
Conference: SAMPE Seattle 2017