通过硅烷偶联剂对氧化钆(Gd2O3)进行表面改性处理制备了改性氧化钆(M-Gd2O3);采用水热法合成了Gd-MOF[Gd4(1,2,4,5-BTEC)3];将聚酰亚胺(PI)分别与Gd2O3、M-Gd2O3、Gd-MOF耦合制备了Gd2O3/PI、M-Gd2O3/PI、Gd-MOF/PI 3种复合屏蔽材料。通过SEM、EDS、FT-IR、TGA对复合屏蔽材料进行表征，结果表明，成功实现了M-Gd2O3与Gd-MOF的合成；在钆质量分数为4%时，3种复合屏蔽材料的T5%均在500℃以上；随着钆质量分数的进一步提高，3种复合屏蔽材料的热稳定性均出现不同程度的下降。拉伸试验结果表明，在钆质量分数为4%时，3种复合屏蔽材料的断裂强度相较于纯PI有不同程度的提升。通过现场实验测量和SuperMC模拟研究了复合材料的热中子屏蔽性能，Gd质量分数为4%的Gd-MOF具有高屏蔽性能、高耐热性

Modified gadolinium oxide ( Gd2O3 ) is prepared through modifying the surface of gadolinium oxide ( Gd2O3 ) by silane coupling agent．Gd-MOF ( Gd4( 1，2，4，5-BTEC) 3 ) is synthesized via hydrothermal method．Gd2O3 /PI，M-Gd2O3 /PI and Gd-MOF/PI composite shielding materials are prepared by coupling polyimide ( PI) with Gd2O3，M-Gd2O3，and Gd-MOF，respectively． These materials are characterized by means of SEM，EDS，FI-IＲ and TGA． It is verified by the results that M-Gd2O3 and Gd-MOF are successfully synthesized．At a gadolinium mass fraction of 4%，the T5% of these three materials are all above 500℃ ．With the further increase of the gadolinium mass fraction，the thermal stability of these three materials decreases to different degrees．The tensile test shows that at a gadolinium mass fraction of 4%，the breaking strength of all three composite shielding materials are higher than pure PI．The shielding properties of these composite shielding materials for thermal neutron are investigated through field experimental measurements and SuperMC simulation．Meanwhile，Gd-MOF with a Gd mass fraction of 4% exhibits high shielding performance and high heat resistance