RESUMEN
A textile material's electromagnetic interference (EMI) shielding effectiveness mainly depends on the material's electrical conductivity and porosity. Enhancing the conductivity of the material surface can effectively improve the electromagnetic shielding effectiveness. However, the use of highly conductive materials increases production cost, and limits the enhancement of electromagnetic shielding effectiveness. This work aims to improve the EMI shielding effectiveness (EMSE) by using an ultrathin multilayer structure and the air-permeable textile MEFTEX. MEFTEX is a copper-coated non-woven ultrathin fabric. The single-layer MEFTEX SE test results show that the higher its mass per unit area (MEFTEX 30), the better its SE property between 56.14 dB and 62.53 dB in the frequency band 30 MHz-1.5 GHz. Through comparative testing of three groups samples, a higher electromagnetic shielding effect is obtained via multilayer structures due to the increase in thickness and decrease of volume electrical resistivity. Compared to a single layer, the EMI shielding effectiveness of five layers of MEFTEX increases by 44.27-83.8%. Due to its ultrathin and porous structure, and considering the balance from porosity and SE, MEFTEX 10 with three to four layers can still maintain air permeability from 2942 L/m2/s-3658 L/m2/s.
RESUMEN
Glaucoma disease therapy frequently involves the application of a glaucoma implant. This approach is effective in terms of reducing the intraocular pressure via the filtering of intraocular fluid from the anterior chamber into the drainage pathways. The basic properties of such implants comprise of long-term stability and the filtering of fluids without the occurrence of undesirable blockages. This study describes the design and production of a novel material for the treatment of glaucoma disease that is based on electrospinning technology. Non-toxic, biocompatible and non-degradable polyvinylidenefluoride (PVDF) was selected as the implant material. The research investigated the resistance of this material to the growth of a fibroblast cell line without the use of antifibrotic agents such as mitomycin C. Three different types of PVDF were electrospun separately and mixed with polyethyleneoxide (PEO), following which the degree of cell growth resistance was evaluated. It was discovered that the fiber layers that contained PVDF blended with PEO evinced a statistically significant difference in metabolic activity compared to the PURE PVDF layers. Only small cell clusters formed on the layers that were resistant to cell fibrotization. As a result of the observed clustering, a new program was developed in MATLAB software for the determination of the number of cells involved in cluster formation, which then allowed for the determination of the spatial dependence between the cells in the form of a point pattern. The study describes a simple technique for the production of composite PVDF+PEO structures suitable for use in the field of glaucoma treatment.
