Smart Fibrous Structures Produced by Electrospinning Using the Combined Effect of PCL/Graphene Nanoplatelets

Abstract

Over the years, the development of adaptable monitoring systems to be integrated into soldiers’ body gear, making them as comfortable and lightweight as possible (avoiding the use of rigid electronics), has become essential. Electrospun microfibers are a great material for this application due to their excellent properties, especially their flexibility and lightness. Their functionalization with graphene nanoplatelets (GNPs) makes them a fantastic alternative for the development of innovative conductive materials. In this work, electrospun membranes based on polycaprolactone (PCL) were impregnated with different GNPs concentrations in order to create an electrically conductive surface with piezoresistive behavior. All the samples were properly characterized, demonstrating the homogeneous distribution and the GNPs’ adsorption onto the membrane’s surfaces. Additionally, the electrical performance of the developed systems was studied, including the electrical conductivity, piezoresistive behavior, and Gauge Factor (GF). A maximum electrical conductivity value of 0.079 S/m was obtained for the 2%GNPs-PCL sample. The developed piezoresistive sensor showed high sensitivity to external pressures and excellent durability to repetitive pressing. The best value of GF (3.20) was obtained for the membranes with 0.5% of GNPs. Hence, this work presents the development of a flexible piezoresistive sensor, based on electrospun PCL microfibers and GNPs, utilizing simple methods.

Study of the Filtration Performance of Multilayer and Multiscale Fibrous Structures

“…The electrospinning process was conducted at 60% ± 5 RH and 20 °C ± 2. The group’s previous studies were consulted to define certain fixed parameters, including voltage, collector-needle distance and the applied solvent [ 20 , 21 ]. The studied conditions and the corresponding produced membranes are presented in Table 2 .…”

Antibacterial and Biodegradable Electrospun Filtering Membranes for Facemasks: An Attempt to Reduce Disposable Masks Use

“…PCL polymer solutions were prepared according to the procedure described by Francavilla et al [13], using 15% (w/v) of PCL in CHF/DMF (4:1). Firstly, PCL pellets were dissolved in CHF and stirred at 35 • C for at least 2 h, until their complete dissolution.…”

“…As already mentioned, to face the accumulation of plastics in the environment, the use of biodegradable polymers is preferable [4]. Among them, synthetic PCL polymer has been demonstrated as a promising candidate for filtration applications, due to its low cost, biocompatibility, biodegradability, availability, excellent mechanical properties and ease of operation [11][12][13].…”

Protective Multifunctional Fibrous Systems Based on Natural Fibers and Metal Oxide Nanoparticles

“…The best value of GF obtained was of 3.20 for the sample with 0.5% of GNPs ( Figure 9 ). Therefore, the developed smart fibrous structures presented a great potential to be used as a wearable sensor, that can be applied on the monitoring of human motions and vital signs for soldier’s equipment applications [ 115 ].…”

“…Piezoresistive response of GNPs-PCL membrane ( b ). Electrical conductivity and GF in relation to the GNPs concentration of GNPs-PCL membrane ( c ) [ 115 ].…”