Investigations on thermal properties of microencapsulated phase-change materials with different acrylate-based copolymer shells as thermal insulation materials

A series of microencapsulated phase-change materials (micro-PCMs) with binary cores and acrylate-based copolymer shells were prepared. The micro-PCMs contained octadecane and butyl stearate as binary-core materials. Allyl methacrylate, ethylene glycol dimethacrylate, 1,4-butanediol diacrylate (BDDA), and 1,6-hexanediol dimethacrylate were respectively introduced to copolymerize with divinylbenzene (DVB) to form different microcapsule shells. In this work, the influence of the types of core and shell materials and core-shell weight ratios on the thermal properties of micro-PCMs was studied. The chemical structures, morphologies, thermal properties, and thermal insulation properties of the wallboards were all tested and discussed. Scanning electron microscope photographs show that these micro-PCMs have relatively spherical profiles and compact surfaces with diameters ranging from 10 to 80 m. Differential scanning calorimetry results indicated that their microencapsulation efficiency ranged from 48 wt % to 80 wt %. A thermogravimetric analysis demonstrated that these micro-PCMs can ensure their thermal stability below 210 degrees C. Finally, a thermal insulation wallboard fabricated with synthesized P(BDDA-co-DVB) micro-PCMs showed excellent thermal energy storage performance, keeping the temperature fluctuation within 2.5 degrees C. (c) 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47777.