Nanocomposites of polyvinyl acetate (PVAc) reinforced with two different TEMPO-oxidized cellulose nanofibrils (CNF) were prepared by casting/evaporation method. These two sets of CNF, designed as CNF-O-5 min (5 min of oxidation) and CNF-O-120 min (120 min of oxidation), are different by their surface charge, geometrical characteristics and crystallinity index. The weight fraction of CNF was changed from 1 to 10 wt%. The mechanical and thermal properties of the nanocomposite films were studied by dynamic mechanical thermal analysis (DMTA), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and tensile tests, and their morphology was investigated by scanning electron microscopy (SEM). For all nanocomposites, increasing amounts of CNF led to a significant increase in the mechanical properties (increase in Young’s modulus and tensile strength) and in the water uptake. On the other hand, the lost of transparency became very significant when the weight fraction of CNF exceeded 3 wt%. The comparison between the two sets of CNF showed that PVAc/CNF-O-5 min nanocomposite films had a tendency to display higher tensile strength and elastic modulus than those of PVAc/CNF-O-120 min films. In addition, the water uptake is higher for PVAc/CNF-O-120 min. Finally, the thermal stability analyses for PVAc/CNF films show that shorter and more charged fibrils (CNF-O-120 min) appear to slightly increase the thermal stability compared to other larger and less charged fibrils (CNF-O-5 min). All these results are discussed in connection with the CNFs characteristics.

通过流延/蒸发法制备了由两种不同的TEMPO-氧化纤维素纳米原纤维（CNF）增强的聚乙酸乙烯酯（PVAc）纳米复合材料。这两组CNF设计为CNF-O-5 分钟（ 氧化5分钟）和CNF-O-120 分钟（ 氧化120分钟），其表面电荷，几何特征和结晶度指标不同。CNF的重量分数从1更改为10 重量％。通过动态机械热分析（DMTA），差示扫描量热法（DSC），热重分析（TGA）和拉伸试验研究了纳米复合膜的机械和热性能，并通过扫描电子显微镜（SEM）研究了它们的形貌。对于所有纳米复合材料，CNF含量的增加导致机械性能（杨氏模量和拉伸强度的提高）和吸水率显着提高。另一方面，当CNF的重量分数超过3 重量％时，透明性的损失变得非常显着。两组CNF的比较表明，PVAc / CNF-O-5  min纳米复合膜具有比PVAc / CNF-O-120更高的拉伸强度和弹性模量的趋势。 分钟电影。此外，PVAc / CNF-O-120 分钟的吸水率更高。最后，对PVAc / CNF薄膜的热稳定性分析表明， 与其他较大且带电较少的原纤维（CNF-O-5 分钟）相比，较短和带较多电的原纤维（CNF-O-120分钟）似乎会稍微提高热稳定性。所有这些结果都结合CNF的特性进行了讨论。