Fabrication of Nepenthes pitcher mimetic water-repellent coating based on solubility parameter theory

Abstract

An azidophenyl-containing fluorinated polymer (PFAz) together with fluoroalkylsilane (FAS) are used as model substances to form an FAS-infused polymer coating on the outermost fabric surface based on solubility parameter theory. It creates a Nepenthes pitcher mimetic water-repellent coating with good durability and self-healing capacity. The results show that lower Ra,FAS-PFAz (3.7–4.3 MPa1/2) tends to drive the formation of FAS-PFAz aggregates in the mixed PFAz-FAS solution firstly. It plays an important role in design of FAS-infused PFAz polymer coating and regulation of water-repellent durability. The appropriate of FAS/PFAz ratio and chemical structure of PFAz are beneficial to avoid the formation of “FAS cage” in the solution and over-crosslinking upon UV exposure. The resultant PFAz22-FAS-SiO2@fabric could resist 240 min of ultrasonication in THF, 700 cycles of Martindale abrasion, 175 cycles of standard laundering tests and 11 cycles of oxygen plasma and heating. It provides a new way to design durable Nepenthes pitcher mimetic coating based on Hansen solubility parameter principle.