Acoustic-field driven nanoparticle organization in semi-crystalline polymer matrix

Previous work demonstrated that nanoparticles (NP) can be organized within amorphous regions of semicrystalline polymers through isothermal crystallization, though slow crystallization rates posed challenges. Applying an acoustic field increases NP diffusivity via acoustic radiation forces, dependent on particle volume, matrix compressibility, and acoustic contrast factor. Experiments with polyethylene oxide (PEO)-silica NP nanocomposites (20 wt%) using probe sonication during crystallization revealed enhanced NP organization, characterized by small-angle X-ray scattering (SAXS). Specifically, at 54oC, an acoustic field significantly accelerated NP ordering, forming structured domains absent without acoustic stimulation. Further studies examine effects of molecular weight, acoustic parameters, and particle size.