Antistatic, Flame-Retardant, and Mechanically Resistant Cellulose/Carbon Black Cryogels for Electrostatic Discharge Packaging

Electrically conductive foams are used as antistatic packaging for electronic items. Traditionally made from petroleum-derived polymers, these materials typically demand high energy for production, generate considerable dust during mixing components, have poor fire resistance, and degrade slowly. To address these issues, this work proposes a sustainable alternative using microfibrillated cellulose (MFC) and carbon black (CB) to create conductive cryogels by the freeze-drying method. The dispersibility of CB in aqueous suspensions of cationic or anionic MFC is studied, and the interactions between components are evaluated using advanced techniques, showing stronger interactions between CB and cationic cellulose. Also, the effect of CB content is assessed on the cryogels’ morphological, mechanical, and electrical properties. Results show cryogels with low densities (<55 mg cm⁻³), high porosities (>91%), strong network structures with high specific compression moduli (11–21 MPa cm³ g⁻¹), and superior fire resistance. Electrical properties vary with CB content: 1–5 wt% CB results in static-dissipative behavior (≈10⁸ Ω cm), while ≥10 wt% CB forms a conductive network (10³–10¹ Ω cm). Overall, cationic MFC/CB cryogels exhibit promising properties, suggesting the potential for replacing plastic-based antistatic foams in electrical applications as a greener alternative.