Research On Enhancement Of Conversion Efficiency And Force Output Of Actuators And Deform-chromic Application

The ionic electroactive polymers,which can produce obvious size or shape change response under external electric stimulation,are a new type of intelligent actuation material.Compared with traditional artificial muscle materials such as shape memory alloy and piezoelectric ceramics,ion electroactive polymers have the advantages of large deformation,high flexibility,low energy consumption and low noise.So they have a wide application prospect in micro-electro-mechanical systems,micro-robots and biomedicine.However,the low electromechanical conversion efficiency and mechanical output of the actuators based on ionic electroactive polymers comparing with traditional actuation materials discourage the further development and application.Therefore,how to improve the conversion efficiency and mechanical properties of ionic electroactive polymer materials is the main direction for further research in this field.In order to solve the above problems,we have introduced the carboxylic MWCNTs into the PEDOT:PSS polymer as the electrode of the electrochemical actuator.The carboxylic MWCNTs achieves good compatibility with PEDOT:PSS polymer through?-?interaction and hydrogen bonding,which not only obviously changes polymer structure but also enhances the electrical conductivity and mechanical properties of the electrodes.Furthermore,we fabricated three-layer structure actuator taking TPU/EMIBF₄ as supporting polymer.The porous structure of electrode promotes the adsorption and aggregation of ions to the electrode and enhances the expansion effect of the electrode.The obtained actuators based on composite electrode displays a greatly improve electromechanical conversion efficiency from 0.019%to 1.04%and enhanced force output from 0.42m N to 1.43mN.In order to further improve the mechanical properties of the actuators,we select the Nafion ion exchange membrane as the electrolyte layer,the methods of multi-layer hot press and solution casting are used to increase the thickness of the ion exchange membrane.The high mechanical properties of the actuator materials are obtained taking carbon tube as the electrode.In addition to that,we also studied the relationship of mechanical properties of the actuators with the actuators'thickness,applied electric field strength and actuation ions form.The obtained actuators produce high force output up to 60.8mN.Then,carbon-encapsulated magnetic Fe₃O₄ particles are synthesized by hydrothermal method and achieve orderly self-assembly in the hydrogel matric through UV curing under the magnetic field.In order to obtain the composite functional materials which can produce deform-chromic response under the electrical stimulation,we combine the photonic hydrogels with the electric actuation materials.