Flexible cellulose acetate nano-felts absorbed with capric-myristic-stearic acid ternary eutectic mixture as form-stable phase-change materials for thermal energy storage/retrieval

摘要

The objective of this study was to explore an innovative type of form-stable phase-change materials (PCMs) with flexible cellulose acetate (CA) nano-fibrous felts (nano-felts) absorbed with capric-myristic-stearic acid ternary eutectic mixture for thermal energy storage/retrieval. Capric-myristic-stearic acid (CMS) ternary eutectic mixture as model PCM was firstly prepared. The developed CA nano-felts as supporting material was mechanically flexible and was made from CA/polyvinylpyrrolidone (PVP) precursor composite nanofibers followed by removal of PVP components. The effects of original mass ratio of CA/PVP on absorption capacities of CA nano-felts were studied. The modified CA nano-felts with groove/porous structure and rough surfaces were capable of absorbing a large amount of PCMs. The morphological structures, as well as the properties of thermal energy storage, thermal stability and reliability, and thermal insulation of composite PCMs were characterized by scanning electron microscopy, differential scanning calorimetry, and thermal performance measurement, respectively. The results showed that CMS eutectic was absorbed in and/or supported by modified CA nano-felts. The heat enthalpy values of composite PCMs have slightly decreased in comparison with the corresponding theoretical values. The composite PCMs demonstrated good thermal stability and reliability after thermal cycles. The composite PCMs had high thermal insulation capability for temperature regulation.