Surface hydrophobization of polyester fibers with poly(methylhydro-dimethyl)siloxane copolymers: Experimental design for testing of modified nonwoven materials as oil spill sorbents

Abstract This paper reports on the hydrophobization of polyester fibrous nonwoven with poly(methylhydro-dimethyl)siloxane copolymers in order to produce water-repellent sorbents for oil spill cleanup. Polysiloxane copolymers were first synthesized and characterized prior to be used as hydrophobization agents. The produced hydrophobic sorbents were characterized by scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy (SEM/EDX); infrared spectra (FTIR) and water-contact angle measurements (WCA). Nonwoven sorbents were evaluated for oil sorption in pure oil bath and in the presence of water ( W -test). A statistical experiment design was employed for materials testing and the development of data-driven models. The optimal hydrophobic nonwoven yielded maximal sorption capacities equal to 5.52 g/g and 10.03 g/g for dodecane and motor oil uptake, respectively. The mechanism of oil attachment on polymeric fibers was investigated by optical microscopy revealing a key role of inter-fiber voids for oil retention. Centrifugation tests demonstrated a high recycling ability of spent nonwoven sorbents.