Polymer materials are commonly used as ablative and insulative materials in rocket propulsion systems and heat shields in re-entry space systems. Ablative materials are required to protect propulsion systems against the particularly hostile flow environment of solid rocket exhaust. For such ablative materials, the polymeric matrix is mostly a resole phenolic resin, such as the Borden Chemical's SC-1008, with or without carbon or graphite fillers as well as glass micro-balloons, depending on the intended use. In Europe and in the US, progresses are being made in the frame of research programs in developing polymer nano-structured materials for high temperature applications. This paper describes the status of the research efforts in this field. The heritage on ablative materials is also based on 2D reinforcements, mainly carbon or graphite clothes, exclusively made from carbonised rayon or poly-acrylonitrile (PAN) fibres. Recently, a breakthrough in ablative materials has been successfully test proven. The innovation is based on the introduction of a new 3D fibrous reinforcement, in place of the 2D reinforcement. The resole phenolic system has been adapted to the RTM injection process, much faster than the standard process of making prepregs, cutting tapes of prepreg, tape wrapping on a mandrel, curing in autoclave, etc, ... Joining in one material the 3D reinforcement and the RTM process provides a lot of advantages, such as higher reliability (no delaminations), higher design margin, cost savings. The 3D carbon reinforcement developed by Snecma Propulsion Solide under the trade name NAXECO, has been successfully fire tested in November 2006 on the larger monolithic solid rocket motor ever made worldwide, the P80 motor, which is designated to power the first stage of the VEGA, the small European launcher. The paper provides information on the results obtained on two NAXECO-based materials: 1. Ablative phenolic materials for exit cone protection, cowl and nose cap. 2. C/C for nozzle throat.
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