橡胶并用体系中填料选择性分布调控及电磁损耗机制研究

Microwave absorbing material is a kind of functional material which can attenuate incident microwave, and has captured its extensive application prospect in military and civil fields. Different interfacial energy-induced preferential distribution of filler in co-continuous blend structure has been confirmed to be a robust strategy for optimizing microstructure and electromagnetic property of resulted composite. However, the analysis of preferential distribution of filler in rubber blend and its electromagnetic loss still does not go into the level of mechanism. Here, based on the previous work, modeled rubber blend with tailor-made distribution of electric/magnetic loss dual fillers will be constructed by analyzing the different interfacial energy of rubber-filler，using various surface modification, applying diverse compounding process. Preferential distribution of filler in rubber blend will be investigated by the combination of online (synchrotron x-ray scattering/optical microscopy–in situ shear, conductance integrated rheology, etc.) and offline (broadband dielectric spectroscopy, positron annihilation lifetime spectroscopy, etc.) characterization methods, thus elucidating the thermodynamic essence and kinetic process for the formation of rubber blend phase structure, filler migration and localized network. Also, filler preferential distribution correlated electromagnetic loss mechanism will be illuminated based on the theories of percolation，waveguide transmission line, interfacial polarization, etc. This work would provide necessary theory for the development of rubber-based microwave absorbing materials with light weight, broad effective bandwidth and high absorption capacity features.

吸波材料是一种能够衰减入射电磁波的功能材料，在军事和民用领域都具有广阔应用前景。利用基体-填料间界面自由能差异，诱导填料在共连续共混结构中选择性分布，是实现吸波材料结构调控与性能优化的最有效途径之一，但对于橡胶体系中填料选择性分布调控及其电磁损耗机制还不清晰。基于前期研究，本项目拟以电/磁损耗双相填料填充的橡胶并用体系为对象，从分析不同基体-填料的界面作用能出发，通过调控组分表面性质、共混工艺等手段构建具有填料选择性分布的共混模型体系。结合同步辐射x-射线散射/光学显微镜-原位剪切，流变-电导联用等在线手段和宽频介电谱、正电子湮没寿命谱等离线手段，研究橡胶并用体系中填料选择性分布规律，揭示相结构变化、填料迁移、局部网络形成的热力学本源和动力学过程；基于渗流理论、波导传输线理论，极化理论等，阐明不同填料选择性分布关联的材料电磁损耗机制，为轻质、宽频、高效的橡胶吸波复合材料设计提供理论依据。

利用基体-填料间界面自由能差异，诱导填料在共连续共混结构中选择性分布，是实现吸波材料结构调控与性能优化的最有效途径之一，但橡胶体系中填料选择性分布调控及其电磁损耗机制还不清晰。基于前期研究，本项目以电/磁损耗双相填料填充的橡胶并用体系为对象，从分析不同基体-填料的界面作用能出发，通过调控组分表面性质、共混工艺等手段实现了橡胶基体中填料可控分布，研究了橡胶并用体系中填料选择性分布规律及其关联的电磁损耗行为和调控机制。通过项目研究，初步建立了填料-橡胶界面浸润热力学参数，揭示了稀土氧化物-碳材料氧空穴诱导的电子跃迁对电磁损耗的增强机制，探明了橡胶分子改性、填料共掺等对橡胶复合材料微观形貌和电磁性能的影响规律，通过拓扑互锁结构构建多了多层级电磁损耗网络，为轻质、宽频、高效的橡胶吸波复合材料设计提供理论依据。