Experimental study demonstrates a polarity-matching dispersion mechanism in polymer nanocomposites, indicating that matrix polarity reduces reliance on energy-intensive mechanical shear.
Key Points
To determine how polymer matrix polarity and mixing methods influence the dispersion, near-infrared blocking, and visible light transmittance of cesium tungsten bronze nanocomposite films.
Fabricated cesium tungsten bronze nanoparticle premixes across three polymer matrices with gradient polarities: non-polar polyethylene (PE), weakly polar ethylene-vinyl acetate (EVA), and strongly polar polyethylene terephthalate (PET).
Compared high-speed shear dispersion with low-energy planetary medium-low speed stirring processes and evaluated optical performance using quantitative spectral analysis.
In non-polar PE, high-speed shear yielded an optimal near-infrared (NIR) blocking rate of ~73% with visible light transmittance (Tvis) of ~52% due to island-like agglomeration, whereas medium-low speed stirring failed to achieve dispersion.
In weakly polar EVA, high-speed shear achieved Tvis of ~61% and NIR blocking of ~64%, while optimized planetary stirring at 45°C improved Tvis to ~73% with ~60% NIR blocking.
In strongly polar PET with an ethyl acetate slurry, chemical anchoring enabled low-energy planetary stirring to achieve Tvis of ~79% and NIR blocking of ~84%, outperforming high-speed shear (Tvis ~82%, NIR blocking ~78%).