Facile Fabrication of Hydrophobic Poly(Lactic Acid)/Polydimethylsiloxane/Octaisobutyl Polyhedral Oligomeric Silsesquioxane Fibers With Excellent Stain Resistance

Poly (lactic acid) (PLA) fibers have gained attention as sustainable alternatives to petroleum-based fibers due to their biodegradability. However, their susceptibility to hydrolysis during washing limits practical applications. This study improves PLA's hydrophobicity and stain resistance by incorporating polydimethylsiloxane (PDMS) and octaisobutyl polyhedral oligomeric silsesquioxane (POSS) via melt spinning. Systematic evaluation of PDMS/POSS ratios revealed that 2.0 wt% PDMS and 0.5 wt% POSS optimally enhance hydrophobicity, achieving a water contact angle of 116 degrees through synergistic low surface energy and micro-nano surface roughness. A cross-shaped fiber design further increased hydrophobicity to 119 degrees. While PDMS and POSS accelerated PLA crystallization, steric hindrance restricted crystal growth. The optimized fibers retained a tensile strength of 4.27 cN/dtex and 28.5% elongation, demonstrating balanced mechanical and hydrophobic properties. These findings present a scalable approach to developing durable, stain-resistant PLA fibers for sustainable textiles.