Design of a Cross-linked PTHF-Based Network as an Oil/Organic Solvent Sorbent

Abstract

Novel effective oil/organic solvent sorbents were designed and comprised entirely from polytetrahydrofuran (PTHF)-based networks in a two-step approach: (1) preparing PTHF-based macro-cross-linkers and (2) cross-linking of PTHF polymers using the prepared PTHF-based macro-cross-linkers. With this approach, different molecular weights of hydroxyfunctional PTHF polymers were turned into ethoxysilane-functional macro-cross-linkers by the modification of hydroxyl groups of PTHF polymers with 3-(triethoxysilyl)propyl isocyanate. Then, the prepared ethoxysilane-functional macro-cross-linkers were condensed with hydroxy-functional PTHF polymers to synthesize PTHF-based networks as oil/organic solvent sorbents. The synthesized PTHF-based sorbents demonstrated superior absorption properties in various oils and organic solvents such as dichloromethane, tetrahydrofuran, benzene, toluene, ethylbenzene, xylene, methyl tertiary butyl ether (MTBE), gasoline, and crude oil. The recovery of the sorbents after repeating the application for the absorption of dichloromethane and MTBE is essential, and they can be reused effectively for at least 50 days without any capacity loss. All the synthesized PTHF-based sorbents depicted high thermal stability. The characterization of the macro-cross-linkers and PTHF-based sorbents were determined by using 1 H, 13 C, and 29 Si nuclear magnetic resonances and Fourier transform infrared spectroscopies. Thermal characteristics of the sorbents were identified by thermogravimetric analysis and differential scanning calorimetry. Absorption kinetics of the sorbents were further analyzed using pseudo-kinetic models and an intraparticle diffusion model.

Coherent Loading–Deloading Mechanism in Polymeric Nanohybrid Network Structures

“…in the hydrogel microstructure facilitate the sorbent process of analytes, and induced multifunctionalities have significant advantages for a wide range of physicochemical applications. 10,11 The desorption of analytes from functional hydrogels, however, remains a great challenge due to the strong polar and electrostatic interactions, and thus the ionic strength of the hydrogel medium is required to be modulated for optimum absorption−desorption equilibrium.…”

“…The dye adsorption or drug delivery vehicles are thus required to be synthesized in such a way that multiple performance objectives are achieved, where both absorption and desorption are equally important. The functional moieties in the hydrogel microstructure facilitate the sorbent process of analytes, and induced multifunctionalities have significant advantages for a wide range of physicochemical applications. , The desorption of analytes from functional hydrogels, however, remains a great challenge due to the strong polar and electrostatic interactions, and thus the ionic strength of the hydrogel medium is required to be modulated for optimum absorption–desorption equilibrium.…”