چكيده به لاتين
In this study, conductive polymer nanocomposites (CPNCs) of PDMS/MWCNT flexible films were prepared by vacuum filtration method that is a technique used in layer-by-layer (LBL) production. First, nanocomposite samples were made in the same wt. % of MWCNTs but on different types of membranes. Then, according to the SEM images CA membrane was selected and Piezoresistive Sensing Elements were made. After manufacturing of sandwich-structured nanocomposites, the electrical and piezoresistive properties of PDMS/MWCNT thin films were discussed. For this, some equipments were made. The first one was Modular apparatus for manufacturing & test of Piezoresistive and piezoelectric polymer nanocomposites under pressure stimuli and the second one was an apparatus for Piezoresistive test of nanocomposite strips under strain stimuli. After preparing the CNT suspension, the concentration of CNT suspension was measured and wt. % of CNT was obtained. Depend on CNT content, the obtained CPNC films exhibited initial electrical resistance in the range of 12.5 KΩ to 22.8 MΩ and a great piezoresistive behavior under strain. The effect of CNT weight density on electrical and piezoresistive properties of CPNC films, as well as the electrical percolation, initial resistance, and variation of electrical resistance by applying strain, was investigated. Also, the mechanical tests such as Dynamic Mechanical Thermal Analysis (DMTA) and Tensile Test was performed and the effects of curing temperature and CNT nanofillers on mechanical Properties were investigated. Finally, PDMS/MWCNTs strips were connected to data acquisition system and tested by Piezoresistive test apparatus under strain stimuli; output signals were processed by the Signal processing code and the results were discussed.