制备了2种离子相互作用强度不同的纳米离子材料(相对强度SiO2-SIT-M2070>SiO2-SIT-Ethomeen).结果表明,分散相SiO2在纳米离子材料中稳定存在,未出现聚集.纳米离子材料中外层低聚物的结晶受到抑制,且离子相互作用越强,结晶抑制作用越明显,对动态流变性质也有显著影响.在相同固含量条件下,纳米离子材料SiO2-SIT-Ethomeen的动态剪切模量和黏度比SiO2-SIT-M2070小1～3个数量级.在动态大应变剪切条件下,高固含量的SiO2-SIT-M2070表现出软玻璃流变学特性;而SiO2-SIT-Ethomeen体系表现出强应变过冲现象,并且随着固含量的升高,其动态模量和黏度出现极大值时所对应的应变值逐渐减小,而且应变过冲的程度逐渐变小.因此通过调节组分间离子相互作用可有效地调节纳米离子材料的流变特性.%We prepared two kinds of silica-based nanoscale ionic materials( NIMs) with increasing SiO2 con-tents, and also with different relative ionic interaction strengths between their constituents( SiO2-SIT-M2070>SiO2-SIT-Ethomeen for the relative ionic interaction strength) . The results of transmission electron microscope ( TEM) and small-angle X-ray scattering ( SAXS ) investigations indicated that there was no obvious nano-particle aggregate in both kinds of NIMs. The differential scanning calorimetry( DSC) results showed that the ionic interactions prohibited the crystallization of out-shell block copolymers in the prepared NIMs. Moreover, the crystallization suppression was more serious with increasing the ionic interaction strength. Ionic interaction also displayed the dramatic influence on the dynamic rheological behavior of as-prepared NIMs. The dynamic shear moduli and viscosities of SiO2-SIT-Ethomeen were about 1—3 orders of magnitude lower than those of SiO2-SIT-M2070 with the same solid contents. Under the shear of large dynamic strain, SiO2-SIT-M2070 with the relatively high solid contents showed the soft glass rheological properties, while SiO2-SIT-Ethomeen showed the phenomenon of strong strain overshoot. Furthermore, the strain that corresponding with the maximum of dynamic shear moduli and viscosities gradually decreased with the increasing of solid contents, and so did the degree of overshoot. All above results suggested that the rheological properties of NIMs could be effectively controlled by carefully tuning the ionic interactions between their constituents.
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