Surface Chemical Modification of Bio-mimetic Materials: Underwater Oil / Fouling Repellency

Abstract

Complementary combination of surface chemical functionality and hierarchical surface topography provides superior and diverse surface properties. We demonstrated under-water oil/fouling repellency on bio-mimetic materials having complementary combination of hydrophilic functionality and hierarchical micro-nano surface topography. Poly(dimethylsiloxane) based bio-mimetic replica (PDMS-replica) was prepared following conventional soft lithography. This PDMS-replica was then functionalized with (3-Aminopropyl)trimethoxysilane to obtain the amino-silane modified PDMS-replicasilica/NH2.

Subsequently, epoxy terminated polyalkylene glycol monoallyl ethers (PG-Ep) were synthesized and characterized by the epoxidation of polyalkylene glycol monoallyl ethers (PG/ polyglycol) using MCPBA. Finally, polyglycol modified PDMS-replica (PDMS-replicasilica/NH2/OH) was prepared by reacting PDMS-replicasilica/NH2 with PG-Ep. The resulted PDMS-replicasilica/NH2/OH showed under-water oil repellency with the oil contact angle, θoil of ~142° under-water. At each stage of the chemical modification, surface composition was analyzed using X-ray photoelectron spectroscopy and wettability was verified using contact angle measurements.