Department of Physics, Harvard University, Cambridge, MA 02138, USA.
Soft Matter. 2017 Sep 27;13(37):6293-6296. doi: 10.1039/c7sm01740e.
We design polystyrene-poly(N'-isopropylacrylamide-co-acrylic acid) core-shell particles that exhibit dynamically tunable scattering. We show that under normal solvent conditions the shell is nearly index-matched to pure water, and the particle scattering is dominated by Rayleigh scattering from the core. As the temperature or salt concentration increases, both the scattering cross-section and the forward scattering increase, characteristic of Mie scatterers. The magnitude of the change in the scattering cross-section and scattering anisotropy can be controlled through the solvent conditions and the size of the core. Such particles may find use as optical switches or optical filters with tunable opacity.
我们设计了具有动态可调散射特性的聚苯乙烯-聚（N'-异丙基丙烯酰胺-co-丙烯酸）核壳粒子。我们表明，在正常溶剂条件下，壳层与纯水几乎具有相同的折射率，粒子散射主要由核心的瑞利散射决定。随着温度或盐浓度的增加，散射截面和前向散射都会增加，这是米氏散射体的特征。散射截面和散射各向异性的变化幅度可以通过溶剂条件和核心的大小来控制。这种粒子可以用作具有可调不透明度的光开关或光学滤波器。
