Preparation and characterization of flame retardant phase change materials by microencapsulated paraffin and diethyl ethylphosphonate with poly(methacrylic acid‐co‐ethyl methacrylate) shell

Abstract

Microcapsules containing paraffin and diethyl ethylphosphonate (DEEP) flame retardant with uncrosslinked and crosslinked poly (methacrylic acid-co-ethyl methacrylate) (P(MAA-co-EMA)) shell were fabricated by suspension-like polymerization. The surface morphologies of the microencapsulated phase change materials (microPCMs) were studied by scanning electron microscopy. The thermal properties and thermal stabilities of the microPCMs were investigated by differential scanning calorimetry (DSC), and thermal gravimetric analysis (TGA). The flame retarding performances of the microcapsule-treated foams were calculated by using an oxygen index instrument. The DSC results showed that the crosslinking of the polymer shell led to an increase in the melting enthalpies of the microcapsule by more than 15%. The crosslinked P(MAA-co-EMA) microcapsules with DEEP and without DEEP have melting enthalpies of 67.2 and 102.9 J/g, respectively. The TGA results indicated that the thermal resistant temperature of the crosslinked microcapsules with DEEP was up to 171 C, which was higher than that of its uncrosslinked counterpart by 20 C. The incorporation of DEEP into the microPCM increased the limiting oxygen index value of the microcapsule-treated foams by over 5%. Thermal images showed that both microcapsule-treated foams with and without DEEP possessed favorably temperature-regulated properties. As a result, the microPCMs with paraffin and DEEP as core and P(MAA-co-EMA) as shell have good thermal energy storage and thermal regulation potentials, such as thermal-regulated foams heat insulation materials.

Graphite nanoparticles-dispersed paraffin/water emulsion with enhanced thermal-physical property and photo-thermal performance

“…The fluids containing PCMs are generally classified into two kinds: microencapsulated PCM slurry and PCM emulsion [14]. Although microencapsulated PCM slurries exhibit enhanced specific heat and good fluidity, they suffer from the complex process for preparing PCM microcapsules [15,16], the damage of the capsule walls during transportation by pumps or other machine, and the significant thermal resistance resulted from the thick capsule walls [17]. Comparatively, PCM emulsions have several advantages such as simple process for emulsifying [18], negligible thermal resistance of the protective surfactant layer, and good operation stability [8].…”

Preparation, characterization, and thermal properties of novel fire-resistant microencapsulated phase change materials based on paraffin and a polystyrene shell

“…Most of these studies are for FS-PCM and only three ref. [22][23][24] and one patent 25 are on the application of re retardant to mPCMs. There are a few recent studies on microencapsulated PCM that have re retardant encapsulated together with the PCM as given in Table 1.…”

The micro‐/nano‐PCMs for thermal energy storage systems: A state of art review

“…Further, the authors suggested that if this rigid PU will be employed in building, the amount of CO 2 leaving to the atmosphere can be reduced resulting in save the energy. Qiu et al prepared the PS foam with microcapsules containing paraffin wax and DEEP as core and PMAA‐co‐EMA as a shell materials and found that micro‐PCM had good thermal regulation potential and TES capacity treated with foam. Later, they synthesised the micro‐PCM of hybrid shell materials of PMMA and UF coated on n ‐tetradecane and found the higher enthalpy of 175.5 J/g.…”