Treatments of Nanofiber Cellulose Biomass for Cementitious Building Materials

The main purpose of this work is to study the effect of the addition of low contents of cellulose nanofibers varying between 0.1 and 1 wt.% on the mechanical and thermal properties of cement-based composites. Three types of modified cellulose nanofibers, noted as NFC1, NFC2 and NFC3, were used in this work to prepare three series of composites based on cement matrix. An increase in the compressive strength was recorded by adding only 0.1 wt.% of NFC and the highest values were obtained at percentages of 0.1 wt.%, 0.7 wt.% and 0.5 wt.% for NFC1, NFC2 and NFC3, respectively. The obtained results confirm that the addition of modified cellulose nanofibers to the cementitious matrix improves the compressive strength of the nanocomposites. It was improved by 128% at a reinforcement rate of 0.7 wt.% of NFC2. The composite’s surface has changed from being hydrophilic to hydrophobic and it was confirmed through contact angle measurements. Furthermore, the thermal conductivity of the nanocomposites decreased remarkably after the addition of cellulose nanofibers to cement mortar and was reduced by up to 58% compared to the control’s thermal conductivity value.