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A novel class of ablative materials using phenolic resin, silica fabric, and nano-zirconium dioxide is being developed as a potential alternative for use in high-heat-flux thermal protection applic...

This paper provides the details of the R&D of a new ablative material through a collaboration between The University of Texas at Austin and Techneglas LLC. The UHTR polysiloxane resin system is man...

In this research, a break-wire-like ablation recession and thermal sensor based on commercial, affordable thermocouples was designed, fabricated, and tested. The objective of this paper was to demo...

A new class of thermal protection materials based on a novel organic silicone polymer system, referred to generically as SM8000, was investigated. The composite material undergoes “ceramitization” on exposure to elevated temperatures under solid rocket exhaust plumes. SM8000 converts in situ to an oxidative resistant ceramic material at elevated temperatures. The remaining char forms a tough, abrasion-resistant surface. This paper summarizes the four year research anddevelopment program in refining, testing, anddeveloping this class of silicone polymer matrix composites as thermal protection materials. Composite design, specifically resin and reinforcement selection, composite geometry, ablation testing method development, as well as both prepreg and laminate manufacturing scale-up issues, were considered as an integral part of this research program. Thermal performance of this new class of silicone-based matrix composites exceeds the performance of the conventional phenolic-based matrix composites. A silicone quartz composite and process were developed that could provide a high-quality, flat, uniformpanelmeasuring 2.44 by 1.22mby9.53mm.SM8000 offers one of the best alternative polymer systems to the phenolic system that has been in use for the last 40 years.

Thermal protection materials are required to protect structural components of space vehicles during the reentry stage, missile launching systems, and solid rocket motors. Novel materials based on nanotechnology creating nontraditional ablators are rapidly changing the technology base for thermal protection systems. In this study, different polymer nanocomposite compositions were created by melt-compounded montmorillonite nanoclays or carbon nanofibers in a neat thermoplastic polyurethane elastomer polymer using twin-screw extrusion. The kinetic and thermophysical properties that are required to analyze the ablation characteristics were measured for selective thermoplastic polyurethane materials. Properties of the nanomodified systems were then compared against those of the current state-of-the-art insulation material, Kevlar®-filled ethylene-propylene-diene monomer and the neat thermoplastic polyurethane elastomer, for the investigation of kinetic parameters using the isoconversion technique. Based on temperatures at peak weight-loss rate, Kevlar-filled ethylene-propylene-diene monomer outranked the proposed formulations at all heating rates. Recognizing that ablation performance is a complex function of kinetic and thermophysical/transport properties, a surrogate test for ablation performance was investigated. Samples of neat and nanomodified thermoplastic elastomer were run in an oxygen-consumption (cone) calorimeter. The peak heat release rates of the nanomodified samples were substantially less than that of the neat thermoplastic elastomer.

The introduction of inorganic nanomaterials as additives into polymer systems has resulted in polymer nanostructured materials exhibiting a multiplicity of high performance characteristics beyond what traditional polymer composites possess. These “multifunctional” features attributable to polymer nanocomposites consist of improved thermal resistance and flame resistance, moisture and chemical resistance, decreased permeability, charge dissipation and conductivity. Through control/alteration of the additive at the nanoscale level, one is able to maximize property enhancement of selected polymer systems to meet or exceed the requirements of current commercial, military, and aerospace applications. The technical approach involves the introduction of nanoparticles into selected polymer matrix systems whereby nanoparticles may be surface-treated to provide hydrophobic characteristics and enhanced inclusion into the hydrophobic polymer matrix. The objectives of this paper are to summarize our current research efforts in the use of polymer nanostructured materials for high temperature applications such as rocket nozzle ablative materials, carbon/carbon composites, and damage tolerant high performance epoxy carbon fiber reinforced composite systems.