Washable and breathable ultrathin copper-coated nonwoven polyethylene terephthalate (PET) fabric with chlorinated poly-para-xylylene (parylene-C) encapsulation for electromagnetic interference shielding application

Abstract

Electromagnetic interference shielding clothing has been developed for people who is sensitive to electromagnetic radiation or workers working under extremely high electromagnetic radiation circumstances. The challenge was developing the fabric with good washability, durability, and air permeability. After three machine washing cycles, the electromagnetic interference shielding effectiveness can drop more than 99% for untreated copper-coated fabric. In this research, the chlorinated poly-para-xylylene (parylene C) encapsulating technology was used to protect the fiber's copper particles. The result shows that the treated sample's washing ability will significantly improve after processing 15 g parylene-C on the copper-coated fabrics. The electromagnetic interference shielding effectiveness can remain at 39.93 dB and 25 dB on average from 30 MHz to 3 GHz after 10 hand washing cycles and 10 machine washing cycles, respectively. The air permeability remains around 1043.6 mm/s for a 15 g parylene-C encapsulated sample. The chemical resistance property was also improved significantly after encapsulation of 15 g parylene-C. For the 15 g parylene-C encapsulated samples, there is less than 3% loss of electromagnetic interference shielding effectiveness after 8 h of immersing into pH = 2 and pH = 12 solution. The overall structure of the 15 g parylene-C encapsulated fabric remains intact after 6000 abrasion cycles. The study presents an effective method for fabricating highly durable, comfortable electromagnetic interference shielding fabric, guaranteeing reliability for technical clothing applications and showing great potential for further development.

Influence of washability treatment on the electromagnetic interference shielding material’s comfort properties

“…Washing (3 min), rinsing (8 min), spin-drying (2 min), and room-temperature drying (4 h) were all steps in one washing cycle. 36 Electromagnetic shielding effectiveness. The basic principle of electromagnetic shielding material is mainly based on wave reflection, wave absorption, and multiple reflections of electromagnetic waves in the material, resulting in the attenuation of electromagnetic wave energy.…”

Mathematical modeling for electromagnetic shielding effectiveness characterization of metalized nonwoven fabrics

“…The volume porosity of nonwoven textiles (V p %) can be calculated according to the fiber volume ratio (V fi %) when ignoring the mass of air in the textile sample, the calculation equation was presented in equation (16).…”

“…14 These textiles find extensive application in the development of electromagnetic shielding clothing, serving to safeguard individuals such as workers and pregnant women who endure prolonged exposure to excessive electromagnetic radiation. 15,16 Additionally, the metalized textiles hold potential as constituents of composite materials employed in construction or as protective materials for sensitive instruments. 17 The electromagnetic shielding performance can be evaluated from the value of shielding effectiveness (SE), which can be measured via coaxial transmission line method according to ASTM 4935-10 18 and calculated from the decimal logarithm of the ratio of incident energy to transmitted energy.…”

Enhanced electromagnetic shielding of lightweight copper-coated nonwoven laminate with carbon filament reinforcement

“…This prevalence is attributable to the well-established processing methodologies associated with metallized textiles, as well as the profound progression in their development and production capacities, particularly concerning their integration within the subsequent domain of clothing industry applications. 10–13 However, conventional textile-based coatings of metal particles on polymer fibers generally lack enough mechanical properties and exhibit limited EMI/ES reliability under large mechanical deformation due to the mechanical character of polymer fibers. 14,15 Besides being high-strength, advanced textile-based EMI shielding materials are also requested to show good thermal resistivity to guarantee that electromagnetic wave-sensitive equipment runs at the proper temperature.…”