The impact of cellulose nanocrystals on the rheology of sodium carboxymethyl cellulose and sodium alginate

Abstract

At present, the physical properties of hydrocolloids limit their wide application in food industry. To improve the viscoelasticity of sodium carboxymethyl cellulose (CMC) and sodium alginate (SA), cellulose nanocrystals (CNCs) were added into CMC and SA solutions to regulate the non‐Newtonian flow behaviors of composite systems under different conditions. The rheological properties of CMC/CNCs or SA/CNCs composite systems were studied using steady rheological measurements, dynamic rheological measurements, and creep compliance experiments. It was found that the viscosities and elastic modulus of CMC were positively related to CNCs concentrations in acid, neutral or alkaline environments. When the CNCs content was higher than 5% at pH 9.45, the gelation of CMC was accelerated, and the gelation strength was increased. The damping factor of SA decreased with increasing calcium ions contents. When calcium ions content was higher than 0.07%, the damping factor of SA was less than 1, indicating that SA system achieved gel transformation. The effect of CNCs on the apparent viscosity, shear stress, and storage modulus of CMC was more obvious in comparison to that of SA. Overall, as a rheology modifier, CNCs can minimize the contents of food colloids in any functional fluid while maintaining the thickening rheology.

Methacrylated Cellulose Nanocrystals as Fillers for the Development of Photo-Cross-Linkable Cytocompatible Biosourced Formulations Targeting 3D Printing

“…Additionally, when the concentration of photosensitive groups in the initial formulation is low, cross-linked hydrogels often display poor mechanical properties, that are insufficient for use as biological tissue scaffolds. , In order to address this problem, integration in the formulation of cellulose nanocrystals (CNCs) as reinforcing fillers can be considered. CNCs are biocompatible cellulose nanorods most commonly obtained by sulfuric acid hydrolysis of a wide variety of cellulose sources that display exceptional mechanical properties, such as a tensile strength of about 10 GPa. − Since the pioneering work of Favier and co-workers, CNCs have widely been considered as reinforcing fillers in nanocomposites, including biocomposites. , In the case of photo-cross-linked CMC hydrogels, strong interactions between the hydrophilic parts of mCMC and the surface of cellulose nanocrystals can be expected, both materials comprising a cellulose backbone enabling hydrogen bonds to form. , Moreover, the dispersion in water of the crystalline cellulose nanorods should allow limiting the transmission of the light beam, especially for wavelengths comparable to their size …”

“…31,32 In the case of photo-cross-linked CMC hydrogels, strong interactions between the hydrophilic parts of mCMC and the surface of cellulose nanocrystals can be expected, both materials comprising a cellulose backbone enabling hydrogen bonds to form. 33,34 Moreover, the dispersion in water of the crystalline cellulose nanorods should allow limiting the transmission of the light beam, especially for wavelengths comparable to their size. 35 In the present paper, the introduction of CNCs into photocross-linkable and printable mCMC formulations has been studied to limit the UV-light transmission in the formulations during insolation, but also to improve the mechanical properties of the final hydrogels.…”