Polymer Engineering and Science, Vol.61, No.4, 1220-1231, 2021
The role of rheological premonitory of hydrogels based on cellulose nanofibers and polymethylsilsesquioxane on the physical properties of corresponding aerogels
Cellulose nanofibers (CNFs) and polymethylsilsesquioxane (PMSQ)-based aerogels (CNF/PMSQ aerogels) have been prepared by the sol-gel method. The extraction of CNFs from pine wood and formation of composite aerogel with PMSQ were confirmed by Fourier transform infrared spectroscopic and field emission scanning electron microscopic analyses. The rheological premonitory of hydrogel has been performed to predict the physical properties (i.e., density, mechanical properties) of aerogels. The variation in the precursor (methyltrimethoxysilane [MTMS]) and urea content has shown a considerable effect on the storage modulus and phase angle of the hydrogel. The variation in urea content showed a 4-8% increment in the density with a pronounced difference in aerogel's morphology. The increment in the MTMS concentration demonstrated a 10-20% enhancement in density with a minor change in morphology. The van Gurp-Palmen plot of hydrogel has represented a relationship between complex modulus and phase angle. This study establishes that hydrogel's premonitory analysis could compare aerogel's physical properties without going through drying and further analysis.