Components of solid rocket motor that are susceptible to ageing are propellant, insulator, inhibitor, interfaces, igniter system, and seals. Seals, insulator, ignition systems are replaceable but the motor would be recast when the deterioration in propellant and liner are beyond specified limits due to the ageing. There is a large body of literature available on the ageing of composite solid propellant, each focusing only on a particular type of ageing in propellants rather than having a synergistic view of the various different ageing processes and hence the literature looks disconnected. Further, there are a few studies which are still classified and are one of the reasons for the above disconnect. This review paper is an attempt towards establishing the bridge among these studies. Different types of ageing: physical, chemical ageing, hygro-chemical ageing and the deterioration associated with cumulative damage have been discussed in detail. The ageing related deterioration plays an important role in the safe-life estimation of solid propellant based rocket motor. Therefore, sources and mechanisms of ageing have been explored and their associated effects on the propellant properties (physical and mechanical) are also described. A summary on accelerated ageing methods which are typically followed to study thermo-chemical ageing of propellants is presented in this paper. Studies related to the degradation of propellant-liner interface are also reviewed. Advances in health monitoring (passive and active) of stored grains have been visited. Further, the gap in propellant ageing research have been identified and suggestions are provided for the future research.

固体火箭发动机易老化的部件是推进剂、绝缘体、抑制剂、接口、点火系统和密封件。密封件、绝缘体、点火系统是可更换的，但当推进剂和衬套由于老化而劣化超过规定限度时，电机将被重新铸造。有大量关于复合固体推进剂老化的文献，每篇文献都只关注推进剂中特定类型的老化，而不是对各种不同的老化过程有协同的看法，因此这些文献看起来是脱节的。此外，还有一些研究仍处于机密状态，这也是造成上述脱节的原因之一。这篇综述论文试图在这些研究之间建立桥梁。不同类型的老化：物理老化、化学老化、已经详细讨论了湿化老化和与累积损坏相关的劣化。老化相关的退化在基于固体推进剂的火箭发动机的安全寿命估计中起着重要作用。因此，已经探索了老化的来源和机制，并且还描述了它们对推进剂特性（物理和机械）的相关影响。本文总结了通常用于研究推进剂热化学老化的加速老化方法。还回顾了与推进剂-衬管界面退化有关的研究。已经访问了储存谷物健康监测（被动和主动）方面的进展。此外，还确定了推进剂老化研究的差距，并为未来的研究提供了建议。