Abstract Currently, carbon nanotubes (CNTs) are used as popular fillers for enhancing the composite insulation materials in solid rocket motors (SRMs). While the mechanical properties of the char layer are enhanced by their use, the thermal insulation performance is reduced. This study proposes to solve this problem by pre-coating CNTs. The surface of CNTs was coated with a carbon layer using chemical vapour deposition (CVD), resulting in an ethylene propylene diene monomer (EPDM) composite insulation material reinforced with coated-CNTs. Furthermore, the ablation experiments were examined using oxyacetylene ablation test (OAT). The experimental results show that, compared with that of the CNTs formulation, the thermal conductivity of the coated-CNTs formulation is significantly reduced. On the other hand, for the coated-CNTs formulation, the temperature response time of the back of the material is increased, while the heating rate and maximum temperature are greatly reduced. In addition, the char layer of the coated-CNTs formulation has better compression resistance compared with that of the CNTs formulation. It is concluded that the coated-CNTs not only improve the thermal insulation performance by reducing the thermal conductivity of the material, but also promote the particle erosion resistance of the insulation material by enhancing the strength of the char layer.

中文翻译：

---

化学气相沉积包覆碳纳米管增强新型乙烯丙烯二烯单体复合材料的隔热和炭层力学性能

摘要 目前，碳纳米管（CNTs）被用作增强固体火箭发动机（SRMs）复合绝缘材料的常用填料。虽然炭层的机械性能通过它们的使用增强，但隔热性能降低。本研究提出通过预涂覆碳纳米管来解决这个问题。使用化学气相沉积（CVD）在碳纳米管表面涂上一层碳层，从而得到一种用涂覆的碳纳米管增强的三元乙丙橡胶（EPDM）复合绝缘材料。此外，使用氧乙炔烧蚀试验（OAT）检查烧蚀实验。实验结果表明，与碳纳米管配方相比，包覆碳纳米管配方的热导率显着降低。另一方面，对于涂层碳纳米管配方，提高了材料背面的温度响应时间，同时大大降低了升温速率和最高温度。此外，与碳纳米管配方相比，碳纳米管涂层配方的炭层具有更好的抗压性。得出的结论是，包覆的碳纳米管不仅通过降低材料的热导率来提高隔热性能，而且还通过提高炭层的强度来提高隔热材料的抗颗粒侵蚀能力。