应用于X射线屏蔽的马来酸钐配合物改性三元乙丙橡胶

Ethylene propylene diene monomer rubber modified by maleic acid samarium complex applied in X-ray shielding

为制备稀土类质量轻且无铅毒的屏蔽材料,首先,利用Sm^2O_3与马来酸酐(MA)通过沉淀法合成了马来酸钐配合物(Sm-MA);然后,将Sm-MA用于改性三元乙丙橡胶(EPDM),制备了Sm-MA/EPDM复合材料;最后,采用TG、FTIR、SEM和XRD对Sm-MA进行测试,并分别表征了Sm-MA/EPDM复合材料的力学性能、微观形貌和屏蔽性能(X射线能量为59.3keV)。TG结果显示Sm-MA在850℃左右热分解失重趋于终止,Sm-MA的总失重率为43.7%,由实验数据算得的Sm-MA中Sm的含量(47.6wt%)与理论计算值46.8wt%基本相符;FTIR谱图显示MA的—COOH特征吸收峰在形成配合物后消失,并出现羧酸根的对称与反对称伸缩振动吸收峰,表明Sm^3+与MA发生键合。力学性能和屏蔽性能测试结果表明Sm-MA能显著增强EPDM的力学性能和屏蔽性能,当Sm-MA与EPDM的质量比为60∶100时,Sm-MA/EPDM复合材料的性能达到最优,拉伸强度为18.3 MPa,补强率达33.6%,屏蔽率达77.1%。所得结论表明添加无毒的金属配合物既可改善复合材料的性能,又能增加其与环境的相容性。

In order to prepare the shielding materials of the rare-earth type which has light weight and unleaded in- nocuity, maleic acid samarium complex （Sm-MA） was synthesized by Sin2O3 and maleic anhydride （MA） through precipitation method firstly. Then, Sm-MA was used to modify ethylene propylene diene monomer rubber （EPDM）, and Sm MA/EPDM composites were prepared. Finally, the Sm-MA was tested by TG, FTIR, SEM and XRD, as well as the mechanical properties, morphology and shielding property （X-ray energy was 59.3 keV） of Sm- MA/EPDM composites were characterized respectively. The TG results show that the thermal decomposition mass loss of Sm-MA is closed to end at about 850 ℃, the total mass loss ratio of Sm MA is 43.7%, and the content of Sm in Sm-MA （47.6wt%） which is calculated by experimental data is approximately consistent with the theoreticaI calculated value 46.8wt%. The FTIR spectra show that the characteristics absorption peak of COOH in MA dis- appears after the formation of complex, as well as symmetrical and antisymmetric stretching vibration absorption peaks of carboxylic acid appear, which means Sm3＋ and MA bonded. Mechanical property and shielding property test results show that SmMA can reinforce both of the mechanical properties and shielding property of EPDM sig- nificantly. When the mass ratio of Sm-MA to EPDM is 60 ： 100, the properties of Sm-MA/EPDM composites reach the best, the tensile strength is 18. 3 MPa, the reinforced ratio reaches 33. 6% and the shielding ratio reaches 77.1%. The conclusions obtained indicate that the addition of innocuity metal complex can not only improve the properties of composites, but also enhances the compatibility with environment.