Hydrophilicity enhancement of mulberry silk fabric through atmospheric pressure dielectric barrier discharge plasma treatment

Mulberry silk fabric (MSF), renowned for its mechanical strength, biocompatibility, and aesthetic luster, exhibits inherently low surface wettability, which restricts its performance in dyeing, finishing, and functionalization processes. This study investigates the enhancement of hydrophilicity of MSF using atmospheric pressure dielectric barrier discharge (DBD) plasma treatment in air. Surface modification was assessed using contact angle goniometry, attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR), and gravimetric analysis. The plasma treatment significantly reduced the water contact angle—from 120.40° ± 2.90° to 40.70° ± 2.20° for raw MSF after 40 min and from 118.70° ± 2.90° to complete wetting (0°) for degummed MSF after only 5 min—indicating a substantial improvement in hydrophilicity. Surface free energy was calculated using the Kwok–Neumann approach, showing an increase after treatment. Gravimetric analysis confirmed material loss, suggesting the removal of surface impurities. FTIR results revealed the formation of new polar functional groups, contributing to enhanced wettability. These findings demonstrate the potential of non-thermal plasma as an eco-friendly technique for tailoring the surface properties of natural textiles, with promising applications in biomedical textiles, moisture management, and sustainable surface engineering.