A Study On Ion-Polymer Metal Composite Modified With Polypyrrole/Silicon And Its Performance

Ionic Polymer Metal Composite（IPMC）, which can produce force and displacement by bending inthe electric field, has great potential application as actuator. Currently, The results at home and abroadshow that IPMC has two major shortcomings: low output force and short air-operation time. Thispaper, starting with the shortcomings of IPMC, applies methods such as organic synthesis to optimizethe performance of IPMC in order to improve the output force and extend the air-operation time. Thedetails are as follows:1, Synthesized the SiO₂nanoparticles with the sulfonic acid groups on its surface. SiO₂nanoparticles and（MeO）3SiSHreflux in the round-bottom flask and further oxidized withH2O2. The FTIR test result shows that there is an obvious peak at1039cm-1.It has been proven that itis the S=O infrared telescopic vibration peak of SO₃H group. This proves that the SiO₂-SO₃Hnanocomposites are synthesized successfully. Based on the actuating mechanisms of IPMC, a test ofion exchange equivalent on SiO₂-SO₃H nanoparticles was conducted.. The result shows that the ionexchange equivalent value of the SiO₂-SO₃H is larger than that of Nafion（0.98mmol/g）. Therefore,immitting SiO₂-SO₃H to IPMC can increase the ion exchange equivalent of Nafion membrane inorder to improve the output force of IPMC.2, Synthesised the polypyrrole/silicon （PPy/SiO₂） composites with different proportion of PPyand SiO₂. The TEM test result shows that the dispersivity of the PPy/SiO₂composite differs with thevariation of the proportion of PPy and SiO₂; Mixing PPy/SiO₂to IPMC can change the characteristicsof the latter. The results reveal that the dispersivity of PPy/SiO₂composites has great influence on theperformance of IPMC. After repeated experiments, a best doping program is reached. Based on thebest doping program, in order to further improve the IPMC performance, PPy/SiO₂-SO₃H polymer isprepared and doped into IPMC. The output force test result of the modified IPMC indicates that bydoping PPy/SiO₂polymers, under the circumstance of2V,2.5V,3V sinusoidal voltage, the maximumoutput force of the IPMC rises respectively from13.575mN,14.981mN,15.977mN to29.378mN,31.195mN,34.681mN, by an average of1.5times.3, Under the effect of electric field, for1-Methyl-3-ethyl-imidazole thiocyanate（[EMIn] SCN）,[EMIn]+, the cation of greater volume migrates to the cathode, the smaller SCN-anion migrates to theanode. According to this theory, and combined with its characteristics of non-volatile, decompositionof high voltage, it is used as an IPMC proton conduction medium instead of water to improve the air operation time of IPMC. The experimental results show that: under the circumstance of4V sinusoidalvoltage, when the effect time of IPMC in the air increases to320s, the IPMC displacement with wateras medium reduces by93%and is almost zero, while the IPMC displacement with [EMIm]SCN asmedium reduces by63%and keeps stable in the long run.