Silicone resins, due to its excellent high thermal stability, are widely applied in high-temperature environment. However, it is still a problem that the initial decomposition temperature of silicone resins is relatively low, which limits their wider applications. In this paper, three kinds of polyhedral oligomeric silsesquioxane (POSS) (aminopropyl, mercaptopropyl and chloropropyl) were synthesized and analyzed by FTIR, NMR and MS for structure characterization and purity analysis. Significant improvement of thermal stability was achieved by incorporating POSS into silicone resins. Three different POSS were used to modify silicone resins, and the effects of different POSS on thermal stability of silicone resins were studied. The results indicated that the thermal stability of octa-aminopropyl POSS modified silicone resins improved most significantly, with the decomposition temperature increased by nearly 45 °C compared with pure silicone resins. Moreover, the thermal decomposition mechanism of silicone resins with different POSS was studied, and chemical simulation indicated the thermal stability of silicone resins greatly improved by forming hydrogen bond between POSS and silicone resins. And the results showed one distinctive mode of increasing thermal stability, forming hydrogen bond to block resin chains' movements.

有机硅树脂由于其优异的高热稳定性而被广泛应用于高温环境中。然而，有机硅树脂的初始分解温度相对较低仍然是一个问题，这限制了它们的广泛应用。本文合成了三种多面体低聚倍半硅氧烷（氨基丙基，巯基丙基和氯丙基），并用FTIR，NMR和MS进行了结构表征和纯度分析。通过将POSS掺入有机硅树脂中，可以显着提高热稳定性。用三种不同的POSS对有机硅树脂进行改性，研究了不同的POSS对有机硅树脂热稳定性的影响。结果表明，与纯有机硅树脂相比，八氨基丙基POSS改性的有机硅树脂的热稳定性得到最大改善，分解温度提高了近45°C。此外，研究了具有不同POSS的有机硅树脂的热分解机理，化学模拟表明，通过在POSS和有机硅树脂之间形成氢键，有机硅树脂的热稳定性大大提高。结果表明，增加热稳定性的一种独特方式是形成氢键以阻止树脂链的运动。化学模拟表明，通过在POSS和有机硅树脂之间形成氢键，有机硅树脂的热稳定性大大提高。结果表明，增加热稳定性的一种独特方式是形成氢键以阻止树脂链的运动。化学模拟表明，通过在POSS和有机硅树脂之间形成氢键，有机硅树脂的热稳定性大大提高。结果表明，增加热稳定性的一种独特方式是，形成氢键以阻止树脂链的运动。