Durability of a lubricant-infused Electrospray Silicon Rubber surface as an anti-icing coating

Slippery liquid-infused porous surfaces (SLIPS) are attracting great interest as anti-icing coatings. However, the most challenging point for SLIPS is their durability. A heptadecafluorodecyl trimethoxysilane-fluorinated hierarchically micro-structured silicone rubber surface was prepared by electrospray method coupled with phase separation which had a contact angle of the lubricant θls(a) = 0°. This study investigated the effects of the surface chemistry, length scale and hierarchy of the surface topography of the underlying substrates on their ability to retain the lubricant during repetitive icing/deicing, water washout and ice-shedding treatments. This study compares the lubricant retention rate, ice formation time and ice adhesion strength. The result demonstrated that SLIPS with a fluorinated hierarchical micro/nano scale substrate maintains the best anti-icing capability. Lubricant in the microscale pores can easily creep up to the surface with nano-scale pores providing stronger capillary forces to hold the lubricant in the pores only if θls(a) = 0° with a rolling hill pattern lubricant surface morphology formed during the loss of lubricant. Such fluorinated hierarchically nano/micro structured substrate will enable the lubricant to completely cover the surface which reduces heterogeneous nucleation and frost propagation velocity.