Microencapsulation of n-hexadecane phase change material by ethyl cellulose polymer

Abstract

Microencapsulation of phase change materials (PCMs) is an attractive opportunity for broadening their applications. In this respect, a novel encapsulating polymer, ethyl cellulose (EC) was used to entrap n-hexadecane (HD) PCM by an emulsion-solvent evaporation method. Emulsifiers strongly influenced the size and morphology of the forming EC-HD composite microcapsules, and they also had a great impact on their thermal properties. All of the three emulsifiers were suitable to prepare quasi core-shell microparticles, though the high porosity of shells resulted in serious leakage in composites prepared by Tween 80, and permeability of particles manufactured by poly(vinyl alcohol) (PVA), as can be stated from scanning electron microscopy and differential scanning calorimetry analysis. Interfacial tension measurements and spreading coefficient analysis enabled the prediction of preparation conditions for usable core-shell microcapsules. Volume weighted mean diameters of the microparticles were 319 m, 92 m and 85 m formed by Tween 80, PVA and poly(methacrylic acid sodium salt) (PMAA), repectively. A significantly higher HD content and latent heat storage capacity could be achieved using PVA and PMAA than with Tween 80. The thermal cycling test indicated good thermal reliability of microcapsules prepared by PMAA, while the energy-storing capacity of composites prepared by PVA decreased substantially, and a dramatic reduction was found in microparticles using Tween 80.

Designing behenic acid microcapsules as novel phase change material for thermal energy storage applications at medium temperature

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Lignin‐retaining porous bamboo‐based reversible thermochromic phase change energy storage composite material

“…The current energy supply and demand situations and the expected growth in air conditioning usage in the near future require methods to manage the peak electrical load of the air conditioning systems. Phase change energy storage materials (PCMs) refer to a functional substance, which utilizes the inherent physical phase change behavior to regulate a large amount of latent heat of phase change over a specified temperature range . So, using PCMs can solve this problem through demand side management .…”

Efficient preparation and characterization of paraffin‐based microcapsules by emulsion polymerization

“…PCMs, which absorb energy upon melting and release heat upon solidifying, have been used in various energy storage applications, such as energy‐saving buildings, solar energy utilization, and temperature‐regulating clothing. PCMs include salt hydrates, fatty acids, esters, and paraffins . Among them, paraffins have attracted more attention for their versatile phase‐change temperatures, high enthalpy, low degree of supercooling, good thermal stability, and relatively low cost.…”

“…Microencapsulation of phase change materials (MEPCMs) is a process of coating PCM droplets with a shell to form microcapsules with diameters of nano‐ to micrometers. So far, many materials have been developed as shell materials to prepare microencapsulated PCMs, including inorganic materials, such as SiO 2 , TiO 2 , and CaCO 3 ; polymers, such as polyurethane, polystyrene, melamine resin, and acrylic; and biomacromolecules, such as silk fibroin, ethyl cellulose, and arabic gum . Melamine resin and acrylic polymers have been the most‐studied shell materials.…”