Mesophases in a Gel from Hydroxypropyl Cellulose/Polyacrylamide

The objective of the present work is to analyze the different mesophases observed in a gel synthesized from hydroxypropyl cellulose (HPC) and polyacrylamide (PAAm) and its phase behavior in water. Hydroxypropyl cellulose is a material derived from cellulose it is non toxic and degradable. HPC is widely used in pharmaceutics, food additives, stabilizer, thickener, etc., HPC is approved by the FDA for use in the food industry. HPC has the characteristic that it forms liquid crystals, depending on the solvent and on the concentration of the polymer. In this work a lower critical solution temperature (LCST) and an upper critical solution temperature (UCST) were observed, the resulting gel showed anisotropic, nematic and cholesteric phases in water, the phase formed depended on the concentration of the polymer.     

Chiral nematic phase formation by aqueous suspensions of cellulose nanocrystals prepared by oxidation with ammonium persulfate

There is continuing interest in the growing family of nanocellulosic materials prepared from plant cell wall material. While most of the research on cellulose nanocrystals has focused on the product of sulfuric acid hydrolysis stabilized by surface sulfate half-esters, cellulose nanocrystals with surface carboxyl groups have also been prepared by oxidation of lignocellulosic materials with ammonium persulfate. The major difference is that the persulfate oxidation leads to nanocrystals stabilized by surface carboxyl groups. Some properties of cellulose nanocrystals from cotton and wood, prepared by persulfate oxidation, are compared with those observed for nanocrystals prepared by sulfuric acid hydrolysis. Evidence from polarized light microscopy showed that the nanocrystal suspensions prepared by persulfate oxidation also form chiral nematic ordered phases in water.     

One step in situ synthesis of Ag/AgCl nanoparticles in a cellulose nanofiber matrix for the development of energy storage paper

Cellulose - In the present work, we prepare Cellulose Nanofibers Films (CNFs) incorporating silver nanostructures (Ag/AgCl nanocubes) in a ratio of 1–20 wt% to the organic matrix. We found...