Ablative composites are highly endothermic sacrificial thermal protection materials that are indispensable to the aerospace industry. Polymeric ablatives are the most versatile and the largest class of thermal protection materials due to their capability to be to varied hyperthermal environments. Carbon/carbon composites have outstanding mechanical properties at higher temperatures but they are susceptible to oxidation. The oxidation is addressed by matrix modification, application of a coat of ultrahigh temperature ceramics (UHTC), or also by the use of nanostructure-toughened UHTC coatings as discussed in this article. The article presents a comprehensive review of the science and technology of four distinct groups of ablative composites (carbon/carbon, carbon/phenolic, carbon/elastomeric and carbon/ceramic). The selection of the best material formulations for a given environment is ratified by the testing techniques, which have also been reviewed along with a brief discussion on the composites recycling technologies and their environmental and economic impacts.

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Ablative composites are highly endothermic sacrificial materials, which undergo ablation wherein the outer surface of the material degrades to form a carbonaceous layer, which isolates the underlying material from intense thermal‐heat‐flux environs. Successful utilization of thermosetting resins modified with varied inorganic fillers to tailor ablative polymer composites for thermal protection systems has accelerated extensive research for the development of new contemporary materials for vast space and defense applications. This article discusses various types of ablative materials, polymer composite‐based ablative materials, ablation mechanism, and applications of ablative materials. Resorcinol formaldehyde (RF) resins, which have a similar chemical backbone to the phenolic formaldehyde (PF) resins, possess several advantages which make it a contender for the next generation of ablative materials. The synthesis, testing, and characterization of RF resin‐based ablative polymer nanocomposites have also been presented in this article.