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 degrees, indicating promising candidates for the new generation comfort and degradable medical protective textiles.