The impact of diatomaceous earth on hydrophobicity transfer characteristics

Abstract

Silicone rubber of composite insulators is extensively utilised because of its superior hydrophobicity and hydrophobicity transfer characteristics, especially in heavily polluted environments. This work investigates the hydrophobicity transfer process of silicone rubber materials with different insoluble substances and explores the impact of microscopic parameters on hydrophobicity transfer. Experiments employed diatomaceous earth and kaolin of various particle sizes and origins as inert substances to analyse their effects on hydrophobicity transfer characteristics. Results indicate that diatomaceous earth, with its porous structure, facilitates faster transfer compared to the dense structure of kaolin. Pore size and specific surface area are critical parameters influencing transfer rates. Larger outer pores accelerate the initial ‘fast process’ while smaller inner pores govern the subsequent ‘slow process’ Fractal characteristics of pores also affect transfer efficiency with higher fractal dimensions leading to more extensive transfer. The hydrophobicity transfer process in silicone rubber involves dynamic diffusion influenced by the complexity of internal channels and surface structures. Enhanced understanding of these mechanisms can improve the performance and reliability of composite insulators in polluted environments.