Bioinspired Environmentally Friendly Amorphous CaCO₃-Based Transparent Composites Comprising Cellulose Nanofibers

Abstract

Amorphous calcium carbonate (ACC) stabilized by acidic macromolecules is a useful material for the development of environmentally friendly composites. In this study, we synthesized transparent and mechanically tough ACC-based composite materials by the incorporation of water-dispersible cellulose derivatives, namely, carboxymethyl cellulose (CMC) and surface-modified crystalline cellulose nanofibers (CNFs). A solution mixing method used in the present work proved to be a powerful and efficient method for the production of mechanically tough and environmentally friendly materials. Molecular-scale interactions between carboxyl groups and Ca 2+ ions induce homogeneous dispersion of CNFs in the composites, and this gives composite films with high transparency and high mechanical properties. The composite films of CMC, CNFs, and ACC at the mixture ratios of 40, 40, and 20 wt %, showed high mechanical properties of 15.8 ± 0.93 GPa for the Young’s modulus and 268 ± 20 MPa for the tensile strength. These designed materials that are based on ACC may open up new opportunities in many fields in applications that require the use of environmentally friendly, biodegradable, mechanically tough, and transparent composite materials.

Grow with the flow – observing the formation of rheotactically patterned bacterial cellulose networks

“…The latter works via diffusive processes 68 or faster, via direct mixing. The intermediate which occurs during the precipitation of CaCO 3 is amorphous calcium carbonate (ACC), which can serve as the inorganic phase after stabilization [69][70][71] or after crystallisation. [72][73][74][75] ACC can be used in a one step process, without the need for a second reagent.…”

Bioinspired Mineralization with Hydroxyapatite and Hierarchical Naturally Aligned Nanofibrillar Cellulose

“…The versatility in the fabrication methods of cellulose could be utilized to tailor the structure and properties of hybrid cellulosic materials. Similarly, the bioinspired mineralization processes, such as the use of soluble templates to stabilize mineral precursors, may be used to produce cellulose-based hybrids with high contents of minerals other than HAp. − The latter might expand the use of cellulosic nanohybrids beyond biomedicine.…”

Preparation and characterization of regenerated cellulose biocomposite film filled with calcium carbonate by in situ precipitation

“…2), the films exhibited light scattering due to the aggregation of the precipitated calcium carbonate microcrystals (Kumar et al 2011). The change in opacity of the RC-CaCO3 films can be ascribed to the light absorption and scattering in the gaps between the cellulose fiber and the micro-nano calcium carbonate particles at the interface because the refractive indices of cellulose and CaCO3 are similar (1.56 to 1.60 vs. 1.58) (Kuo et al 2018;Mohamadzadeh-Saghavaz et al 2014). Translucent or almost opaque films can be achieved depending on the loading of calcium carbonate.…”