In this study, the molecular dynamics method was used to explore the effects of the degradation of an adhesion agent (PEG-TDI) in a nitrate ester plasticized polyether propellant on the compatibility and diffusibility of energetic plasticizers (NG and BTTN) and the glass transition temperature and mechanical properties of the blend system (PEG-TDI/NG/BTTN). The radial distribution function, the mean square radius of gyration, and fractional free volume of the PEG-TDI/NG/BTTN system under different degrees of degradation conditions were calculated. The diffusibility and compatibility of NG and BTTN, the glass transition temperature, and the mechanical properties of the blended system were then discussed. The results showed that, with aggravation of the degree of PEG-TDI degradation, the fractional free volume in the system decreased, intermolecular hydrogen bonding and van der Waals interactions enhanced, and the size of the polymeric nematic decreased. These changes eventually caused the diffusion ability of NG and BTTN to weaken, compatibility to be enhanced, and glass transition temperature, stiffness, and yield strength of the PEG-TDI/NG/BTTN system to increase.

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In order to verify whether the coating can meet the stringent requirements of the ship’s long sailing cycle, harsh environment, and various unfavorable factors such as fire conditions, physical and mechanical performance tests, endurance tests, and Micro and micro tests of the three coating samples were carried out. The hardness of the ZS2000, ZS hybrid and ZS1000 coatings measured by the experiment were ⩾8H, ⩾7H, ⩾3H, respectively; the thermal conductivity values of the three coatings are very low, respectively 0.074 W/(m·K), 0.034 W/(m·K) and 0.025 W/(m·K), which can meet the requirements of the engine in unexpected flame environment; the original adhesion of the coating is the best, but the adhesion of the coating is reduced after the damp heat cycle and the salt corrosion at room temperature, and the salt spray resistance, damp and heat resistance of the coating are good, and no obvious defect is observed; TG experiments have found that the remaining percentages of the three coatings ZS1000, ZS2000, and ZS hybrid are 85.29%, 80.72% and 77.90% respectively. The thermal stability of ZS1000 is the best, and the three coatings have the best remaining balance. The difference is not large, so they all have good thermal stability. Analyzing the results of a series of performance tests, it is found that the comprehensive performance of the ZS hybrid coating is better than that of the ZS2000 and ZS1000 coatings.

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