Tuning the Morphology and Hydrophobicity of Polymerized High Internal Phase Emulsion Scaffolds by Compositional Control through Incorporation of Bioderived Eugenol

Abstract

Abstract The utilization of bio-based monomers to fabricate porous polyHIPE frameworks is often discouraged due to the limited reactivity of these monomers for polymerization. The present work highlights the challenges associated with using these monomers for polyHIPE fabrication and the plausible strategies to mitigate these challenges. To this end, eugenol was selected as a bio-based monomer, and it was functionalized to obtain eugenol acrylate (EUA) to overcome its limited reactivity. To fabricate polyHIPEs, EUA, 2-ethylhexyl acrylate (EHA), divinylbenzene (DVB), and emulsifiers (Hypermer 1083) were used. Nevertheless, to achieve a polyHIPE structure from biomass-derived monomers (EUA), it was necessary to incorporate hydrophobized silica particles along with Hypermer surfactant as the primary emulsifier. The impact of different factors, such as the monomer volume ratios, the nature and concentration of the emulsifier, and the internal phase volume fraction, on the properties of the resulting polyHIPEs was further scrutinized. With variation in these parameters, the fabricated polyHIPEs exhibited porosities (up to 90%), specific surface areas (up to 64 m2/g), and low densities (<0.2 g/cm3), resulting in a lightweight yet functionally effective nature. Their unique interconnected pore structure, along with their chemical composition, endows the produced polyHIPEs with superhydrophobicity (with a water contact angle exceeding 145°) and excellent lipophilicity. These porous scaffolds demonstrated high oil absorption capacity for various oils. The system displayed excellent recyclability and reusability with trivial performance loss over ten consecutive cycles. The development of these superhydrophobic polyHIPEs presents remarkable potential for oil spill remediation and other industrial applications where such properties are beneficial.