Thermoregulating Papers Containing Fabricated Microencapsulated Phase Change Materials through Pickering Emulsion Templating

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.

Porous scaffolds with the structure of an interpenetrating polymer network made by gelatin methacrylated nanoparticle-stabilized high internal phase emulsion polymerization targeted for tissue engineering

“…Moreover, the occurred limited coalescence phenomenon due to the droplets' repulsion forces with the same charge induced by negatively surface-charged GelMA particles (at pHs higher than 6) and positively surface-charged GelMA particles (at pHs lower than 6) led to the narrow droplet size distributions. 36 The stability of emulsions was monitored for a month, and creaming was observed in all emulsions due to the lower density of coconut oil than water and imposition of buoyancy forces on coconut oil droplets. So, the smaller droplets migrate more slowly than the larger ones to the top of the vial.…”

3D-Printed Regular-Porous Structure with Trapezoidal Multiple Microchannels as Combustion Reaction Support for the Autothermal Methanol Steam Reforming Microreactor for Hydrogen Production

“…According to the reaction rate equation, ,− reaction heat equation, − convection heat transfer equation, − and related research works, ,, a temperature distribution model of MC reaction support is proposed, as shown in eq . Equation introduces the temperature of the i th region of the CRS in the MC reaction process.…”

Phase‐change composites silicone rubber/paraffin@SiO2 microcapsules with different core/shell ratio for thermal management

“…T m , T c, and T R refer to the melting temperature, crystallization temperature and rotator phase‐transition temperature. The encapsulation ratio (R) and encapsulation efficiency (E) are two important thermal performance parameters of the microcapsules and composites, which can be calculated by Equations () and () 50‐52 : where ΔH m and ΔH c are the phase‐change latent heat during the melting and crystallization process of the microcapsules or composites, respectively. ΔH m,PCM and ΔH c,PCM refer to the phase‐change enthalpy during melting and crystallization of pure paraffin.…”

“…T m , T c, and T R refer to the melting temperature, crystallization temperature and rotator phase-transition temperature. The encapsulation ratio (R) and encapsulation efficiency (E) are two important thermal performance parameters of the microcapsules and composites, which can be calculated by Equations ( 1) and (2) [50][51][52] :…”