Different cellulose nanofibers (CNF) and ordinary Portland cement (OPC) were combined to prepare CNF-OPC composite pastes at different water to cement ratios (W/C) to optimize density, thermal conductivity, and mechanical strength. The rheological data of CNF-OPC composites showed that the viscosity and yield stress of the mixtures were abruptly increased in comparison to those of OPC pastes at equal W/C. Rheological and morphological data showed that the uniformity of the CNF and degree of fiber entanglement plays a significant role in tuning the composite properties. CNF suspensions with short fibers were observed to improve the mechanical properties of the composite while suspensions with entangled fiber networks were found to decrease density and thermal conductivity. Loss of flexural strength of CNF-OPC compared to OPC was found to be to a lesser extent than loss of compressive strength. The dry density and thermal conductivity of the CNF-OPC composites were substantially reduced to the range of 750 (kg/m) and 0.1 (W/mK) at W/C = 2. CNF caused a reduction in peak temperature and postponed the hydration peak by more than 2 h compared to OPC.

中文翻译：

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选择来自环保来源的合适纤维素纳米纤维，用于生产具有调整流变、机械和微观结构性能的轻质水泥基复合材料


将不同的纤维素纳米纤维（CNF）和普通波特兰水泥（OPC）组合在一起，制备不同水灰比（W/C）的CNF-OPC复合浆体，以优化密度、导热性和机械强度。 CNF-OPC 复合材料的流变数据表明，与相同 W/C 的 OPC 浆料相比，混合物的粘度和屈服应力突然增加。流变学和形态学数据表明，CNF 的均匀性和纤维缠结程度在调节复合材料性能方面起着重要作用。研究发现，含有短纤维的 CNF 悬浮液可以改善复合材料的机械性能，而含有缠结纤维网络的悬浮液则可以降低密度和导热率。与 OPC 相比，CNF-OPC 的弯曲强度损失程度小于压缩强度损失程度。当 W/C = 2 时，CNF-OPC 复合材料的干密度和导热系数大幅降低至 750 (kg/m) 和 0.1 (W/mK) 范围。CNF 导致峰值温度降低并推迟水化与 OPC 相比，峰值时间延长了 2 小时以上。