Development of PVA/PEG-silane composites pillared activated bentonite for hydrophilic sponge material

Abstract

Abstract Hydrophilic sponge composites were designed with a combination of polymers using a silane agent (Polydimethylsiloxane (PDMS), Octhyltriethoxysilane (OTES)), Polyethylene glycol (PEG), Polyvinylalcohol (PVA) and activated natural bentonite (B). We describe a simple method of hydrophilic sponge composites preparation with hydrophilic characteristics. The preparation of activated natural bentonite was proceeded by washing in distilled water followed by curing heated at 150°C for 1 hour. The V1 hydrophilic sponge composites were prepared in the ratio of PDMS: Zn: PVA: PEG= 1: 1: 1: 1 (w/w). Through the same synthesis steps, we also prepared for V2 (2:1:1:1), V3 (1:1:2:1), and V4 (1:1:1:2). Then, activated bentonite (B) was added to V1, V2, V3, and V4 hydrophilic sponge composites, respectively, to obtained B-V1 PDMS, B-V2 PDMS, B-V3 PDMS, B-V4 PDMS, B-V1 OTES, B-V2 OTES, B-V3 OTES, and B-V4 OTES. The research also studies the physical characteristics of bentonite, and PVA/PEG-silane composites using X-Ray diffraction (XRD), Attenuated total reflection-Fourier transform infrared (ATR-FTIR) spectroscopy, and Scanning Electron Microscopy (SEM). Even though, the physical hydrophilic characteristic of sponges was identified by the water contact angle measurement. It has been observed that the most hydrophilic materials are in B-V4 PDMS and B-V4 OTES. The presence of more PEG can cause the contact angle to be smaller or more hydrophilic, but its presence needs to be limited and further reviewed regarding its solubility in fuel oil. It concludes that hydrophilic sponge B-V4 has potential application as the separation of water from fuel oil.