Robust anisotropic polyvinyl alcohol/glass fiber composites fabricated via hydrogen bonding interactions and freezing–thawing under stretching

Fabrication of composites with hierarchically anisotropic structure and excellent mechanical properties is still challenging. Inspired by biological tissues with excellent anisotropic microstructure, in this study, a simple method for preparing robust anisotropic polyvinyl alcohol/glass fiber (PVA/GFs) composites with superior mechanical properties was proposed, which based on hydrogen bonding interactions and freeze–thaw method under tensile conditions. Surface-initiated atom transfer radical polymerization (SI-ATRP) was applied for grafting polymers onto the glass fiber. The glass fibers grafted with polymers (GFs) were introduced into PVA. After that, the freeze–thaw method under tensile conditions was adopted to control the formation of hierarchically anisotropic structure, which composed of anisotropic polymer network and orderly aligned glass fibers. The results also showed that the strength and toughness of the composites were significantly improved, due to the interfacial hydrogen bonding interactions between PVA and GFs. Therefore, this study could provide a meaningful idea for preparing anisotropic biomaterials with prominent properties for artificial tissues.