Biodegradable PEO/cellulose-based solid-solid phase change materials

A series of poly(ethylene oxide) (PEO) blends with cellulose (CEL) or cellulose derivatives-carboxymethyl cellulose (CMC), cellulose acetate (CAC), and cellulose ether (CET)-has been investigated as phase change materials for thermal energy storage. For PEO/CEL blends solid-solid phase transition has been observed in the whole concentration's range; for PEO/CMC and PEO/CET blends solid-solid phase transition has been found for PEO content 25 or 50 and 25 wt%, respectively. Otherwise, solid-liquid phase transition takes place. MTDSC investigations revealed that for PEO/CEL and PEO/CMC blends transition the strongest recrystallization effect (as evidenced by exothermic effect in reversing heat flow) as melting process occurred. FTIR analysis shows a shift of the stretching vibration bands of both the proton-donor O-H groups from CEL and PEO due to intermolecular hydrogen interactions between the blends' components. Copyright (C) 2010 John Wiley & Sons, Ltd.