The Effect of Nano-Silica Modified With Silane Coupling Agents on the Diffusion Behavior of Water Molecules in Palm Oil Based on Molecular Simulation

Zhengxiang Zhang,Feng Zhao,Dongsheng Liu,Chao Tang,Wentao Li,Haibin Zhou

doi:10.1109/access.2021.3085980

Abstract

To enhance the compatibility of nano-SiO 2 and palm oil, four different types of silane coupling agent (KH550, KH560, KH570 and KH792) were adopted to modify the surface of silica. It turns out that when using the KH792 to modify the surface of nano-SiO 2 , the interfacial bonding between silica and palm oil was maximum and their overlapping area was the largest, up to 12 Å. Thus, it can be concluded that the relatively optimal silane coupling agent is KH792. And when nano-SiO 2 , whose surface was modified with KH792, was added to the palm oil, the interaction energy between palm oil and water molecules was enhanced and the diffusibility of water molecules in oil was decreased. In addition, the addition of nano-SiO 2 to the oil reduced the diffusible space of water molecules provided by oil and further restricted the diffusion of water molecules in oil. Therefore, it can be seen that the addition of nano-SiO 2 to palm oil may cause the restriction of the diffusion of water molecules in it.

Highlights

In the dielectric materials field, the usage of nanomaterial modification technology has been the research hotspot [1], [2], and it can be used to improve the electricity [3], [4], heat conduction [5], [6] and aging [7], [8] of insulation oil
The results showed that nanoSiO2 modified with silane coupling agent (KH792) could obtain the highest interfacial binding energy and binding energy density [17]
The corresponding groups of KH550, KH560, KH570 and KH792 selected in this paper are amino group (-NH2), epoxy group (−O − CH2 − CH(O)CH2), methylacrylloxyl group (−O − CO−C(CH3) = CH2) and N-(β-aminoethyl)-γ -aminopropyl group (−NH − CH2 − CH2 − NH2)

Summary

INTRODUCTION

In the dielectric materials field, the usage of nanomaterial modification technology has been the research hotspot [1], [2], and it can be used to improve the electricity [3], [4], heat conduction [5], [6] and aging [7], [8] of insulation oil. For the improvement of compatibility between nanoparticles and matrix materials, silane coupling agent was utilized to modify the surface of nano SiO2. Z. Zhang et al.: Effect of Nano-Silica Modified With Silane Coupling Agents on Diffusion Behavior of Water Molecules. The effect of SiO2 nanoparticles on the diffusion of water molecules in palm oil was investigated. Through analysis of interfacial interaction and concentration distribution, determined the relatively optimal silane coupling agent; besides, surface-modified silica was added to palm oil, and the effect of nanoparticles on the diffusion of water molecules in palm oil was investigated by analyzing the mean square displacement of water molecules in palm oil containing nanoparticles, the free volume, and the interaction energy between them.

RESULTS AND DISCUSSION

DIFFUSION BEHAVIOR OF WATER MOLECULES IN

CONCLUSION