Preparation And Electrorheological Properties Of Ionic Liquid-modified Titanium Dioxide Particles

Electrorheological fluid is a kind of smart suspension composed of electrically polarizable particles and insulating oil.The micro/nano particles in the suspension can form a chain structure from a random dispersion state under the stimulation of an electric field with a response time of milliseconds.This transition is fast and reversible.As a disperse phase material,titanium dioxide has been widely concerned by researchers due to its high dielectric constant,good thermal stability and environmental friendliness.However,pure titanium dioxide itself has poor conductivity and cannot exhibit strong electrorheological effects under a DC electric field.In order to further optimize the performance of titanium dioxide-based electrorheological materials,this paper prepared titanium dioxide and ionic liquid modified titanium dioxide microspheres by various methods,and characterized their structure by SEM,TEM,FT-IR,TG,XRD and BET.The effect of particle structure and ionic liquid modification on its response performance under electric field was studied.The specific research content is as follows:(1)Through the selection of different structure directing agents(dodecylamine,hexadecylamine and ammonia)in the sol-gel process,titanium dioxide microspheres with different particle sizes were synthesized,which provides an inorganic matrix with good morphology for the subsequent modification of ionic liquids.Through rheological tests,it is found that the titanium dioxide microspheres prepared with the aid of dodecylamine have higher electrorheological properties and stable performance.(2)The ionic liquid is fixed in the titanium dioxide matrix by the physical restriction method of one-pot method and two-step method to prepare the ionic liquid/titanium dioxide hybrid material.Through the characterization of structure and performance,it is found that a small amount of ionic liquid has been successfully introduced into the titanium dioxide matrix,and the hybrid material obtained by the one-pot method has high yield stress and low zero-field viscosity,and the hybrid material obtained by the two-step method has poor electrorheological properties.(3)Two methods were used to compound titanium dioxide into the polyionic liquid matrix,and the polyionic liquid/titanium dioxide composite material was prepared.The results showed that titanium dioxide and polyionic liquid were successfully combined with two different composite structures.Through rheological tests,it is found that the introduction of titanium dioxide can improve the electrorheological properties of the polyionic liquid base,and the composite particles prepared by the Copolymerization method have higher electrorheological properties and efficiency.