Novel Materials and Nanotechnology Group, IATA, CSIC, Avda. Agustín Escardino, 7, 46980 Paterna, Valencia, Spain.
Carbohydr Polym. 2013 Oct 15;98(1):1072-82. doi: 10.1016/j.carbpol.2013.07.020. Epub 2013 Jul 17.
This study reports on the development and characterization of bacterial cellulose (BCNW) films coated with hydrophobic layers, presenting enhanced barrier properties. Pure BCNW films showed good transparency and thermal stability, high rigidity and extremely low oxygen permeability at 0%RH. The dramatic increase in oxygen permeability at 80%RH, due to the hydrophilic character of BCNW, was counteracted through coating the films with annealed PLA electrospun nanostructured fibres or hydrophobic silanes. The use of electrospinning was crucial to attain a good adhesion between the hydrophilic BCNW and the hydrophobic PLA layer. After electrospinning, the fibres were homogenised by annealing, thus obtaining a uniform and continuous coating. Coated systems showed a hydrophobic surface and protected the BCNW from moisture, thus reducing ca. 70% the water permeability and up to 97% the oxygen permeability at 80%RH. Furthermore, this novel approach was seen to protect BCNW films from moisture more efficiently than coating with hydrophobic silanes.
本研究报告了具有疏水性层的细菌纤维素（BCNW）薄膜的开发和特性，该薄膜具有增强的阻隔性能。纯 BCNW 薄膜具有良好的透明度和热稳定性，在 0%相对湿度（RH）下具有高刚性和极低的氧气透过率。由于 BCNW 的亲水性，在 80%RH 下氧气透过率急剧增加，通过用退火 PLA 静电纺纳米纤维或疏水性硅烷涂覆薄膜来对抗这种情况。使用静电纺丝对于获得亲水 BCNW 和疏水性 PLA 层之间的良好附着力至关重要。静电纺丝后，通过退火使纤维均匀化，从而获得均匀连续的涂层。涂层系统具有疏水性表面，能够保护 BCNW 免受水分的影响，从而将 80%RH 下的水透过率降低约 70%，氧气透过率降低 97%。此外，与用疏水性硅烷涂覆相比，这种新方法能够更有效地保护 BCNW 薄膜免受水分的影响。
