This study aimed to evaluate the effect of nanocellulose addition on the physical–mechanical properties of the paper produced from different fiber blends, besides comparing two nanocellulose addition methods. Three different fibers were used for fiber blending (eucalyptus, sisal, and pine). Handsheets were formed based on the mixing of all possible combinations at a 45/55 ratio in 2% consistency and 60 g/m2. Handsheet reinforcements were performed by two methods: The mixture method (MT) was a mixture of nanocellulose along with pulp during paper formation in 3, 5, and 10% addition; the coating method (CT) was the superficial coating of dry formed papers in 10% addition. Nanocellulose was produced by mechanical microfibrillation of sisal pulp. Handsheets were evaluated by physical and strength properties. Nanocellulose addition increased thickness, volume, grammage, apparent density, opacity, roughness, tensile strength, tensile index, stretch, bursting index, tear index, and fold endurance by 8.7, 8.8, 10.4, 2.1, 4.1, 23.2, 45.7, 31.8, 20.1, 14.2, 21.1, and 271.6% but reduced bulk, brightness, and air permeance by 1.9, 3.4, and 71.7%, respectively. The reinforcement methods presented distinct results. In physical properties, an increasing tendency toward nanocellulose (MT) increase was observed in thickness, grammage, and apparent density despite the decreasing trend in air permeance. No tendency was observed in other physical properties. In general, CT presented higher values of thickness, grammage, bulk, and brightness but lower values of apparent density and opacity, compared to MT. The mixture method showed an increasing tendency in strength properties with the increase of nanocellulose content. CT obtained fewer strength properties compared to MT.

中文翻译：

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通过纤维混合生产的纸张中的纳米纤维素增强

除了比较两种纳米纤维素添加方法之外，本研究旨在评估纳米纤维素添加对不同纤维混合物生产的纸张的物理机械性能的影响。三种不同的纤维用于纤维混合（桉树、剑麻和松树）。手抄纸是基于所有可能的组合以 45/55 的比例以 2% 的稠度和 60 g/m2 混合而成的。通过两种方法进行手抄纸增强：混合法 (MT) 是在造纸过程中将纳米纤维素与纸浆混合，添加 3%、5% 和 10%；涂布法 (CT) 是干法成型纸表面涂布，添加 10%。纳米纤维素是通过剑麻纸浆的机械微纤化生产的。通过物理和强度特性评价手抄纸。纳米纤维素的添加增加了厚度，体积、克重、表观密度、不透明度、粗糙度、拉伸强度、拉伸指数、拉伸、爆破指数、撕裂指数和耐折度为 8.7、8.8、10.4、2.1、4.1、23.2、45.7、31.8、20.1、14.2、21.1和 271.6%，但体积、亮度和透气性分别降低了 1.9、3.4 和 71.7%。强化方法呈现出不同的结果。在物理性质方面，尽管透气性呈下降趋势，但在厚度、克重和表观密度方面观察到纳米纤维素 (MT) 增加的趋势增加。在其他物理特性中没有观察到趋势。一般而言，与 MT 相比，CT 显示出更高的厚度、克重、体积和亮度值，但表观密度和不透明度的值更低。随着纳米纤维素含量的增加，混合法的强度性能有增加的趋势。与 MT 相比，CT 获得的强度特性较少。