Konjac glucomannan-based foams incorporating cellulose phase change microcapsules for efficient thermal energy regulation

Biomass foam with porous structure has broad application prospects in thermal energy management. However, traditional foams can only passively insulate heat, unable to effectively store thermal energy and prolong the insulation time. In this work, microcapsules rich in paraffin were prepared using the Pickering emulsion template method with phosphorylated cellulose nanocrystals (CNC) as an emulsifier. Phase change microcapsules were combined with konjac glucomannan (KGM) foam to prepare thermal energy management materials with excellent thermal insulation and storage properties. The synergistic interaction between CNC and KGM molecules could form the hydrogen bond cross-linking network to further improve the water resistance and mechanical properties of foams. The encapsulation of CNC microcapsules and the capillary action of KGM foam could effectively inhibit paraffin leakage in the KGM/CNC/paraffin (KCP) foams. Moreover, the enthalpy of melting and crystallization of KCP-8 foam was 144.9 J/g and 141.3 J/g, respectively. The thermal conductivity and infrared thermal imaging results showed that KCP-8 foams exhibited excellent thermal insulation and heat storage properties. This study provides ideas for the design and preparation of porous foams with thermal regulation properties, which has great potential in the field of intelligent textile and building energy conservation.