This study pioneers the use of cellulose nanofibres (CNF) as a means to restricting the chloride-ion ingress in cement based systems. Three CNF variants, differing in their carboxylate content from 0.13 to 1.13 mmol/g of the nanofibre, were introduced to paste and mortar mixtures alike, at up to 1.2% by volume fraction of the dry nanofibre. The reference mixture was a plain system, prepared with CSA Type GU Portland cement. The ingress of chloride ions was investigated per the rRapid Chloride Penetration Test (ASTM C1202) and further assessed by colorimetry. Companion studies were conducted to measure changes to the air-void network and the pH environment within. The results demonstrate that adding CNF significantly impedes chloride-ion penetration, most likely due to a lower porosity in the 10 nm–140 nm range. Higher amounts of carboxyl groups, $\left[COOH\right]$, uniformly led to higher CNF efficiency, both for easy workability and for restricting the chloride ingress. So that, for 0.50% fibre volume fraction, and the CNF variant grafted with 1.13 mmol of carboxylate/g, the mortar witnessed a 50% drop in the measured electrical charge as well as in the depth of chloride penetration. The study indicates that the $\left[COOH\right]$ groups scavenge the soluble calcium cations $C{a}^{2+}$, from the aqueous phase of the cement paste without, however, altering the pH therein.

这项研究开创了使用纤维素纳米纤维（CNF）作为限制水泥基系统中氯离子进入的手段。将三种CNF变体的羧酸盐含量从0.13到1.13 mmol / g纳米纤维不同，引入浆料和砂浆混合物中，其含量高达干纳米纤维的1.2％。参比混合物为普通体系，由CSA类型GU波特兰水泥制备。根据快速氯化物渗透测试（ASTM C1202）研究了氯离子的进入，并通过比色法进行了进一步评估。进行同伴研究以测量气孔网络和其中的pH环境的变化。结果表明，添加CNF会显着阻碍氯离子的渗透，这很可能是由于孔隙率在10 nm至140 nm范围内较低。较高数量的羧基，$\left[CØØH\right]$均匀地提高了CNF效率，既易于操作，又可限制氯化物的进入。因此，对于0.50％的纤维体积分数，以及用1.13 mmol / g的羧酸接枝的CNF变体，砂浆的测得电荷和氯化物渗透深度降低了50％。研究表明$\left[CØØH\right]$ 基团清除可溶性钙阳离子 $C{\mathrm{一种}}^{2+}$，但不改变其中的pH值。