Preparation Of Flexible Sensor Based On Polymer Gel And Study On Their Properties

Stretchable and flexible sensors capable of differentiating multiple mechanical stimuli modes are significant to the developments of electronic skin,health detection and acoustic detection underwater etc.In this dissertation,a novel mechanism that embedded deformable metal network electrodes can induce the capacitance change of electric double layer(EDL)in the polymer gel is proposed,to detect various mechanical stimuli modes such as stretching and vertical pressure with high sensitivity.To demonstrate this novel capacitive sensing mechanism,flexible capacity-sensitive materials based on hydrogel and conducting sponge were designed and fabricated,and the effects of fillers,thickness and cross linking degree of hydrogel to the sensing capability and mechanical property of the sensing materials were investigated.It is discovered that the capacitive sensitivity and mechanical properties of the sensor are mainly influenced by fillers,thickness and cross linking degree of hydrogel.The capacitive sensitivity and mechanical properties of hydrogel-filled conductive sponge are better than that of ionic solution filled ones.With the increase of thickness,the capacitive sensitivity to mechanical stimuli including vertical pressure and parallel tension are both decreased,but the mechanical properties such as tensile and compressive strength are both increased.With the increase of the cross linking degree,the capacitive sensitivity to vertical pressure and parallel tension are both decreased,and the reproducibility remained unchanged,but the tensile and compression properties are both increased.