Improving waterproof-breathable capability of degradable macroporous film/hemp hydroentangled nonwovens composite membranes by porous structure and surface wettability modification

Due to recent serious COVID-19 pandemic, medical protective materials with outstanding microbial barrier and liquid barrier property have attracted much attention. However, the crucial issue of improving the waterproof-breathable capability and degradable properties of medical protective material is still challenging. In this research, poly(butyleneadipate-co-terephthalate) (PBAT)/hemp@silica-polyvinylsilsesquioxane (SiO2-PVSQ) composite membranes with good moisture permeability and waterproof property were fabricated. Firstly, hemp and cotton fibers were mixed and hemp/cotton hydroentangled nonwovens were produced to endow the membranes with outstanding water vapor penetration and mechanical properties. Then, degradable PBAT macroporous membranes were prepared by non-solvent induced phase separation (NIPS) method, and combined with hemp/cotton hydroentangled nonwovens to endow the composite membranes with waterproof property. Finally, SiO2 particles were hydrophobically modified by vinyltrimethoxysilane (VTMOS) and grafted on the surface of PBAT/hemp composite membranes. The waterproof property of composite membranes was further improved by hierarchical rough structure and low surface tension hydrophobic groups on the membrane surface. The prepared PBAT/hemp@SiO2-PVSQ composite membranes showed excellent tensile strength with high moisture permeability, good waterproof and water contact angle of 139.5°, indicating promising candidates for the new generation comfort and degradable medical protective textiles.