Yamaguchi Tetsuji, Yamamoto Tetsuya
HORIBA, Ltd., 2 Miyanohigashi, Kisshoin, Minami-ku, Kyoto, 601-8510, Japan.
Department of Chemical Systems Engineering, Nagoya University, Nagoya, 464-8603, Japan.
Anal Sci. 2024 Oct;40(10):1881-1888. doi: 10.1007/s44211-024-00623-6. Epub 2024 Jun 24.
Porous hybrid microparticles are characterized by their densities and porosities. Consequently, the evaluation for density and porosity of porous hybrid microparticles in liquids is crucial for predicting the transport of particles in the atmosphere, human body, and industrial processes. However, direct measurement of the density and porosity of porous hybrid microparticles in liquids remains a challenge. In this study, we investigated the centrifugal sedimentation of polystyrene-silica hybrid microparticles with and without gas-containing closed pores. A centrifugal liquid sedimentation-dynamic light scattering combined analytical method was employed to determine the apparent densities of hybrid microparticles with and without gas-containing closed pores. The porosity of the hybrid microparticles with gas-containing closed pores was elucidated based on the inner buoyancy, which is a centrifugal force generated by the presence of low-density gas inside numerous closed pores. Further, the inner gas buoyancy was analyzed to estimate the particle porosity in liquids. The results obtained in this study confirmed the feasibility of utilizing the proposed method to determine the apparent density and porosity of porous hybrid microparticles in liquids.
多孔杂化微粒的特征在于其密度和孔隙率。因此，评估液体中多孔杂化微粒的密度和孔隙率对于预测微粒在大气、人体和工业过程中的传输至关重要。然而，直接测量液体中多孔杂化微粒的密度和孔隙率仍然是一项挑战。在本研究中，我们研究了含气封闭孔和不含气封闭孔的聚苯乙烯-二氧化硅杂化微粒的离心沉降。采用离心液体沉降-动态光散射联合分析方法来测定含气封闭孔和不含气封闭孔的杂化微粒的表观密度。基于内部浮力阐明了含气封闭孔的杂化微粒的孔隙率，内部浮力是由众多封闭孔内存在的低密度气体产生的离心力。此外，对内部气体浮力进行了分析，以估计液体中的颗粒孔隙率。本研究获得的结果证实了利用所提出的方法来测定液体中多孔杂化微粒的表观密度和孔隙率的可行性。
