Bacterial cellulose reinforced PVA/PVP double-network hydrogels with different PVA/PVP content were prepared via repeated freezing and thawing method.The structure and properties of the composite hydrogels were studied through X-ray diffraction(XRD)

infrared spectrum(IR)

scanning electron microscopy(SEM) and mechanical test.SEM results showed that PVP and PVA adsorbed evenly around the BC fiber filaments in BC/PVA/PVP hydrogels

which resulted in the fully rehydration of the composite xerogels in hot water.XRD results showed that there were significant differences between the crystallization of heat-dried and freeze-dried xerogel samples.The crystallization of both BC and PVA were better in heat-dried samples.In addition

the crystallization of BC was inhibited obviously by PVP and PVA.The effect of PVP on the crystallization of PVA in BC/PVA/PVP was similar to that in PVA/PVP hydrolgels.The mechanical test results demonstrated that the mechanical properties of the PVP/PVA hydrogels were strongly enhanced after being reinforced with the net of BC nanofibers.Furthermore

the content of PVP and PVA had an obvious effect on the mechanical properties of the composites.The dynamic viscoelasticity results also showed the strengthen effect of BC

while the elasticity of BC reinforced hydrogels decreased.