Fabrication of biocompatible super stable lubricant-immobilized slippery surfaces by grafting a polydimethylsiloxane brush: excellent boiling water resistance, hot liquid repellency and long-term slippery stability†
Abstract
Slippery liquid-infused surfaces that imitate the microstructure of carnivorous Nepenthes have attracted widespread attention due to their excellent liquid and various organic solution repellency, associated with broad applications in various fields. However, the complicated preparation processes and poor oil lock ability of slippery liquid-infused surfaces severely restrict their practical application. Herein, lubricant-immobilized slippery surfaces (LISS) were fabricated by grafting polydimethylsiloxane onto ZnO nanorods under ultraviolet light, with residual non-bound silicone oil acting as a lubricant. In addition, the entire reaction is green, and the chemicals involved are inexpensive and environmentally friendly. Moreover, due to the strong intermolecular forces between the non-bound silicone oil and grafted polydimethylsiloxane, silicone oil is firmly locked to the zinc oxide surface, serving as a lubricant layer with a sliding angle of less than 3°. The LISS not only exhibited superior omniphobicity at room-temperature but also retained excellent sliding ability for high-temperature liquids such as hot water and oleic oil. When subjected to a boiling and high temperature test for 15 min, the liquids still slid on the surface with the tilt angles below 4° due to the presence of a uniform lubricant layer. In addition, under extreme operating conditions, such as high shear rate of up to 7000 rpm, long-term immersion for 400 h and strong acid/alkali, the LISS exhibited outstanding slippery stability. Furthermore, its properties of corrosion resistance, anti-icing and anti-fouling are of great significance for extending the practical application of LISS. Therefore, due to their excellent boiling water/hot liquid repellency and long-term slippery stability, the LISS may be promoted on a large scale and are a breakthrough for traditional slippery surface preparation.