Fabrication Of Functionalized Conducting Polymer Fibers,Physical Characteristics And The Potential Applications In Strain Sensor

With the development of intelligent electrons,flexible wearable devices have attracted considerable attention for the remarkable characteristics,such as flexible,stretchable,foldable,twistedable,comfortable,portable and functional etc.As we all know,the sensor is the core component of flexible wearable electronic device,therefore,the characteristics of the sensor play an important role in determining the characteristic of the design and function of the wearable electronic device in the future.Compared with other traditional electrical sensors,the sensors based on the fibers have the advantages of flexibility,lightweight,high sensibility,comfortability,high stability and self-standing etc.In the present case,based on the fibrous senor,we tried three methods to obtain sensors with unique stretchability and sensibility to the stretching,pressure,temperature etc.In addition,for the miniaturizationof the device,we discuss the possible mechanism of single nanofiber.At first,we report a simple,facile,cost-effective,and convenient method to fabricate stretchable,portable,environment friendly,patterned strain PANI/PVDF sensors based on electrospinning of PVDF and in situ polymer.Owing to the patterned structure,the patterned PANI/PVDF sensor can measure and withstand strain up to 110%,which is higher than the corresponding unwoven sensor.Moreover,it also exhibits some positive qualities,such as stability,durability.Sensitivity tests show fast response,and stability and repeatedly response to tapping and finger motion.These features of high stretchability,elasticability,repeatability,durability,stability and sensitivity allow this material to be used as a good sensor.Secondly,a simple magnetic-mechanical spinning has been used to fabricate ultrafine parallel PANI/PVDF/?-Fe2O3 fibers.The spinning setup is so facile and inexpensive that does not require special training or skills.Particularly,the electromagnetic functionalized composite fibers have excellent mechanical properties,showing a Young's modulus of 0.99 MP and an ultrahigh stretchability of 440%.Moreover,strain sensor based on the twisted fibers shows fast and repeatable response to finger pressure.These results indicate that the magnetic-field-assisted one-step spinning technique may be a facile and effective route for design and preparation of multifunctional polymer/?-Fe2O3 composite fibers,and their good properties(high length,outstanding stretchability and high resolution to pressure)provide promising possibleapplications in stretchable devices,sensors,electromagnetic interference shielding,and magnetic drug delivery etc.Thirdly,based on the unique stretchability of elastic which is made of PU,additionally,better electronic characteristics of PANI.We fabricate a low-cost strategy blending in situ polymerization of PANI on the elastic to fabricate stretchable,and conductive PANI/PU sensor inherits good electrical and mechanical characteristic from its constituents.For example,the PANI/PU strain sensor can detect the strain up to1400%,at which point the sensor ruptures.Moreover,it can remain high conductivity even facing the limit of the strain.Additionally,sensitive tests of finger motion and pressure are all demonstrating the potential applications in stretchable and wearable devices.Finally,Single conducting polypyrrole(PPY)nanowires doped with p-toluene sulfonamide(PTSA)are synthesized by a template-free self-assembly method.Electronic transport characteristics of an individual polypyrrole/p-Toluenesulfonamide(PPY/PTSA)nanofibrous device have been studied in a wide temperature range from 300 down to 40 K.It is found that the measured current-voltage(I-V)data measured can be well fitted by space charge limited current(SCLC)theory from 300 down to 100 K.Trap plays a very important role in understanding the I-V characteristics in solid state physics,the corresponding trap energy and trap concentration are also obtained based on SCLC theory.The carrier mobility is 0.964 cm2 V-1 s-1 on the basis of trap free of 160 K.However it is interesting to find that little current can be found at lower voltages for the temperature below 80 K,furthermore,it follows the equation I ?(V/Vt-1)? at higher bias.We attribute the phenomena to the Coulomb blockade effect.The second part of the section is the electronic transport behavior of single PANI-CSA nanofiber device,which is explained by the phonon theory,to our surprise,there also exist the deviations between the original I-V and the fitted curve in the lower voltage,which can be attributed to the electron-electron interaction.Additionally,these two models are feasible for single organic nanofiber devices.