Preparation and characterization of morphological and mechanical properties of cellulose cryogel nanofibers reinforced by different polyamide resins.

As environmentally friendly materials, cellulose cryogels are good choices due to their biodegradability and ease of use. However, the most crucial issue concerning cellulose cryogels is their weakness in terms of mechanical properties. In this study, two types of Polyamide-Epichlorohydrine resins, named PAE1 and PAE2, and Polyamide-Glutaraldehide-Epichlorohydrine resin (PGE) were synthesized; they were utilized to reinforce cellulose nanofiber gel (CNFG), and this was followed by the freeze-drying process. The density and porosity of the cryogels were improved and evaluated using mathematical equations. The mechanical behavior of the fabricated specimens was examined to obtain the optimized values of processing time and temperature, as well as the resin weight fraction, which yielded the improvement of compressive modulus, yield strength, and the stress at 60% strain (S60) to 2 (MPa), 50 (kPa), and 1.8 (MPa) respectively. Also, attenuated total reflection (ATR) analysis was conducted to study the effect of resins on the cross-linking of cellulose nanofibers (CNF)s; further, nitrogen adsorption–desorption analysis was performed to investigate the specific surface area and mesopore diameter distribution of cryogels using Brunauer–Emmett–Teller (BET) and Barrett-Joyner-Halenda (BJH) methods, respectively. [ABSTRACT FROM AUTHOR]