Thermoregulating Papers Containing Fabricated Microencapsulated Phase Change Materials through Pickering Emulsion Templating
Zeynab Bakeshlou, Nasser Nikfarjam
Abstract
The main purpose of this study is to develop papers with thermoregulation performance. The papers were made of nanofibrillated cellulose containing microencapsulated phase change materials (n-hexadecane), called MicroCapPCM. The papers can conserve actual solar energy and postpone warming of the hand-made house for around 30 min in comparison to bare roof or paper without MicroCapPCMs. The MicroCapPCMs were realized from oil-in-water Pickering emulsion templating, where emulsion droplets were stabilized by Fe3O4@GOQD@Gel nanoparticles, which are composed of Fe3O4 nanoparticles decorated with graphene oxide quantum dot and gelatin, respectively. The polymerization of oil phase containing hexadecane, styrene, and cross-linker gives microcapsules with a PCM core surrounded by a nanocomposite shell. The formed polymer/inorganic hybridization can improve the thermal conductivity of the shell to accelerate heat transfer. The successfully synthesized nanoparticles of 150 nm in size have both magnetic and pH-sensitive features showing well-stabilizing efficiency to form different droplet sizes with manipulation of nanoparticle content and pH. FE-SEM micrographs revealed a multinucleus morphology for the core and collapsed/wrinkled morphology for the surface of the MicroCapPCMs. The thermal and barrier properties of MicroCapPCMs were studied using DSC and TGA analyses. The results indicated that the encapsulation efficiency was varied from 97 to 22% with increasing styrene content in the oil phase. Finally, these temperature-regulating papers can be developed for potential applications such as intelligent textiles, ceiling or inner wall of greenhouses, and panels used in energy-efficient smart buildings.