Thermal Insulation Mechanism, Preparation, and Modification of Nanocellulose Aerogels: A Review

Abstract

Energy problems have become increasingly prominent. The use of thermal insulation materials is an effective measure to save energy. As an efficient energy-saving material, nanocellulose aerogels have broad application prospects. However, nanocellulose aerogels have problems such as poor mechanical properties, high flammability, and they easily absorbs water from the environment. These defects restrict their thermal insulation performance and severely limit their application. This review analyzes the thermal insulation mechanism of nanocellulose aerogels and summarizes the methods of preparing them from biomass raw materials. In addition, aiming at the inherent defects of nanocellulose aerogels, this review focuses on the methods used to improve their mechanical properties, flame retardancy, and hydrophobicity in order to prepare high-performance thermal insulation materials in line with the concept of sustainable development, thereby promoting energy conservation, rational use, and expanding the application of nanocellulose aerogels.

Lightweight polybenzoxazole aerogels with high compressive strength, ultralow dielectric constants, and excellent thermal stability

“…Under the conditions of this study, the radiant conductivity was negligible, the gas conductivity was related to the porosity, and the solid thermal conductivity was related to the properties of the resin material. 45,46 Moreover, the thermal conductivity increased as the mass fraction of the polymer increased. This is because porosity affects the thermal conductivity.…”