Microfluidic Preparation of Microencapsulated Phase Change Materials with Polyurea/Polymethyl Methacrylate Shell for Thermal Energy Storage

A facile three-step approach was presented to prepare microencapsulated phase change materials (MEPCMs) with n-octadecane as core and polyurea/polymethyl methacrylate (PUA/PMMA) as shell.First, a droplet-based microfluidic technique was introduced to generate microdroplets of n-octadecane with controllable size.Then, an interfacial polymerization technique was employed to form a protective shell of PUA on microdroplets to prevent them from collapse and coalescence.Finally, an in-situ polymerization technique was adopted to form a compact shell of PMMA inside the PUA shell to improve the thermal performance of MEPCMs.The MEPCMs with PUA/PMMA double-layered shell exhibited high monodispersed in size and sphericity, good phase-change performance, and enhanced thermal stability and durability for thermal energy storage applications.