目的 采用能与有机硅单体反应的耐热小分子对苯基硅树脂基吸波涂层进行增韧改性，调控有机硅树脂的交联网络结构，并将改性树脂与耐温吸波剂复合，制备具有高柔韧、高附着力和耐温的吸波涂层。方法 将不同端基或链长的耐热增韧剂通过硅氢加成接枝到有机硅树脂基体，改变基体的交联网络结构，通过红外、扫描电镜、万能电子试验机、动态热机械分析仪和矢量网络分析仪测试其性能。结果 随着乙烯基封端聚二甲基硅氧烷含量的增加，涂层的柔韧性提高，但耐温性能和附着力降低;当乙烯基封端聚二甲基硅氧烷质量分数为45%时，1 mm涂层的柔韧性达20 mm，附着力达7.73 MPa，抗冲击性大于50 kg.cm。在300 ℃热处理15 h后，改性涂层挠度从未改性时的1.08 mm提升至1.35 mm，涂层在高温工作后仍保持较好的柔韧性。结论 采用耐热线型小分子对有机硅树脂交联网络结构进行改性，可有效地调控耐温吸波涂层的力学性能，为耐高温吸波涂层增韧及其工程应用提供参考。

The work aims to control the cross-linking network structure of silicone resin by toughening and modifying the phenyl silicone resin-based microwave absorbing coating with heat-resistant small molecules that can react with organic silicone monomer, and compound the modified silicone resin with heat-resistant absorbent to develop heat-resistant microwave absorbing coatings with high flexibility, high adhesion and thermal stability. Toughening modifiers with different end groups or chain length were grafted to silicone resin by hydrosilylation addition reaction to change the crosslinking networks of the matrix. The properties of the coatings were tested by infrared spectrum, SEM, mechanical properties and dynamic mechanical thermal analyzer. With the increase in content of vinyl-terminated poly (dimethyl siloxanes), the flexibility of the coating was improved, whereas the heat-resistant and adhesion were reduced. When the content of vinyl-terminated poly (dimethyl siloxanes) increased to 45 wt. %, the flexibility of the 1 mm coating reached 20 mm, with adhesion as high as 7.73 MPa and impact resistance of higher than 50 kg∙cm. After working at 300 °C for 15 h, the flexibility of the coating increased from 1.08 mm for unmodified coating to 1.35 mm. Moreover, the modified coatings maintained good flexibility after heat treatment. Modifying the crosslinking networks of silicone resin with heat-resistant small molecules can effectively control the mechanical properties of heat-resistant microwave absorbing coatings and provide references for toughening and engineering applications of heat-resistant microwave absorbing coatings.