Comprehensive characterization of hygroscopic, fire‐retardant and thermally insulating sulfated nanocellulose aerogelJaouahar, Mohamed (Avtor) Hanani, Zouhair (Avtor) Ablouh, El-Houssaine (Avtor) Humar, Miha (Avtor) El Achaby, Mounir (Avtor) Sehaqui, Houssine (Avtor) sulfated nanocelluloseaerogelflame-retardancythermal insulationmoisture adsorptionNanocellulose aerogel is an interesting class of materials that combines lightweight, high porosity, and exceptional insulating properties of aerogels with abundance, renewability, and biodegradability of cellulose. These eco-friendly materials are highly desirable in insulation applications to replace petroleum-based counterparts, thus responding to major global challenges related to climate change and resources depletion. Herein, a nanocellulose aerogel with sulfate moieties (S-NC), is prepared via functionalization of cellulose in H2SO4 /urea, followed by mechanical defibrillation and freeze-drying processes. Advanced techniques such as static and dynamic compression tests, SEM, DVS, TG-MS, XPS, and micro combustion calorimetry were used to assess S-NC characteristics and comprehend its thermal behavior. As a result of its ultra-high porosity (99.3 %), and its sulfate-half ester functional groups, the S-NC aerogel exhibits both a low thermal conductivity of 26 mW.(m·K)-1 and a pronounced flame-retardant behavior. The total heat release registered by microscale combustion calorimetry analysis is only 1.68 kJ.g−1 for the S-NC aerogel. In addition, the hygroscopicity of the aerogel was evaluated via water vapor sorption analysis and fitted to the Guggenheim-Anderson-de Boer (GAB) model, revealing a type II sorption mechanism with moisture buffering capacity of 0.63 g/g S-NC at 95 % relative humidity. The S-NC aerogel is eco-friendly material combining moisture adsorption with flame retardancy and thermal insulation, properties that are critical for safety and performance in applications vulnerable to heat and fire risks.20252025-02-10 11:02:36Članek v reviji167115sl