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Condensations of tetraethyl orthosilicate (TEOS) with cyclohexanediol derivative monomers at moderately high temperatures resulted in the creation of crosslinked poly(orthosilicate)s. The structural and thermal properties of the crosslinked poly(orthosilicate)s polymers were determined by Fourier transform infrared spectroscopy, solid-state 13 C and 29 Si crosspolarization magic angle spinning nuclear magnetic resonance, thermogravimetric analysis and differential scanning calorimetry. The synthesized crosslinked polymers were found to be insoluble in common organic solvents, such as tetrahydrofuran, dichloromethane, benzene and acetone, although they displayed swelling abilities in these solvents. The swelling ability of the crosslinked polymers was examined by the swelling test, swelling kinetics and desorption kinetics. The results suggest that crosslinked poly(orthosilicate)s based on cyclohexanediols can find good use as absorbents for organic solvents.

This article describes the preparation of poly(ethylene glycol) (PEG) -based gels for removal of both organic solvents and water through a clean synthesis process without using any initiator, catalyst, activator, or liquid medium. The synthesis of the gels is based on the condensation of different molecular weights of PEG macromolecules with the nine-functional crosslinker tris[3-(trimethoxysilyl) propyl] isocyanurate (ICS). Solid-state 13 C and 29 Si crosspolarization magic angle spinning (CPMAS) nuclear magnetic resonance (NMR), Fourier transform infrared spectroscopy (FTIR), and elemental analysis were used to characterize the prepared sorbents. Thermal properties of the synthesized sorbents were examined using thermal gravimetric analysis (TGA) and differential scanning calorimetry (DSC). The swelling capacities of the sorbents were determined by swelling tests in dichloromethane (DCM), tetrahydrofuran (THF), benzene, acetone, and toluene. The water absorbency of the PEG-based sorbents is also investigated. The effect of the reaction time and reaction temperature on swelling features of the sorbents was studied systematically. The prepared PEG gels have high swelling ratios both in polar and nonpolar solvents.

Condensations of cyclohexanedimethanol derivatives with tetraethyl orthosilicate in the proper stoichiometric ratio produce crosslinked poly(orthosilicate)s. Synthesized crosslinked polymers have swelling abilities in common organic solvents such as tetrahydrofuran (THF), dichloromethane, benzene and acetone. All these polymers are moderately thermally stable and possess solvent uptake abilities that are not only good and fast but are also regen-erable. FTIR, solid-state 13 C, 29 Si-NMR and thermal methods were used to characterize these synthesized polymers. The effects of different cyclohexanedimethanol derivatives on the properties of polymers were also examined.

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