Out‐of‐Water Constitutional Self‐Organization of Chitosan–Cinnamaldehyde Dynagels

Abstract

An investigation of the constitutional adaptive gelation process of chitosan/cinnamaldehyde (C/Cy) dynagels is reported. These gels generate timely variant macroscopic organization across extended scales. In the first stage, imine-bond formation takes place "in-water" and generates low-ordered hydrogels. The progressive formation of imine bonds further induces "out-of-water" increased reactivity within interdigitated hydrophobic self-assembled layers of Cy, with a protecting environmental effect against hydrolysis and that leads to the stabilization of the imine bonds. The hydrophobic swelling due to Cy layers at the interfaces reaches a critical step when lamellar self-organized hybrids are generated (24 hours). This induces an important restructuration of the hydrogels on the micrometric scale, thus resulting in the formation of highly ordered microporous xerogel morphologies of high potential interest for chemical separations, drug delivery, and sensors.

Molecular amorphous glasses toward large azomethine crystals with aggregation-induced emission

“…A particular aspect of the FTIR spectra is the position of stretching band characteristic to phenoxy/ether unit. 10 In all the FTIR spectra of the studied compounds, even those which do not contain hydroxy/ether groups, a weak, broad band appears around 3430 cm -1 , which can be attributed to water clustering via hydrogen bonding to the azomethine units. In the FTIR spectra of the compounds containing an -OH group in para position to the Schiff base unit (1,6,11) the phenoxy band appears even more shifted, around 1285 cm -1 , exhibiting a significant displacement of approximately 35 cm -1 , indicative of the intermolecular hydrogen bonding of phenol groups [9].…”

“…1 H NMR (300 MHz, d6DMSO, ppm) δ = 9.65 (s, 1H, CH=N), 9.30, 9.27 (d, 1H, H a ), 8.80, 8.77 (d, 1H, H i ), 8.42, 8.39, 8.36, 8.34, 8.31, 8.28, 8.25 P2 -4-(((2,3,5,6,8,9,11,12-octahydrobenzo[b] [1,4,7,10,13] pentaoxacyclopentadecin-15-yl)imino)methyl)phenol, 11 has been synthesized by condensation of one equivalent of vanillin (0.152 g, 10 -3 mol) with one equivalent of 4'-amino -2-(((2,3,5,6,8,9,11,12-octahydrobenzo[b] [1,4,7,10,13] pentaoxacyclopentadecin- 15-yl) 1-(((2,3,5,6,8,9,11,12octahydrobenzo[b] [1,4,7,10,13]pentaoxa cyclopentadecin-15-yl)imino)methyl)naphthalen-2-ol, 13, has been synthesized by condensation of one equivalent of 2- (5), c = 31.0182 (11) N-(anthracen-9-ylmethylene)-2,3, 5,6,8,9,11,12-octahydro benzo[b] [1,4,7,10,13] (7), b = 8.7672 (3), c = 13.8699 (6) N-((1,5a1-dihydropyren-1-yl)methylene)-2,3, 5,6,8,9,11,12-octa hydrobenzo[b] [1,4,7,10,13] Please do not adjust margins Please do not adjust margins (buthyl, octhyl) or macrocyclic benzo-15-crown-5 ether substituents have been selected for this study. They were subjected to conceive fifteen low molecular weight azomethines with variable hard/soft component ratio by using the amino-carbonyl/imine reversible chemistry (Table 1).…”

“…The imine band is shifted toward lower wavenumbers for pyrene-containing compounds (5,10,15) indicating lowering of the imine bond energy and a better conjugation. All the other specific bands are present in the FTIR spectra.…”

“…Remarkable changes have been observed during the aging processes. Among the isotropic samples, some of them became crystalline (1,5,6,10,13), while others remained amorphous (11,14,15) or became partial crystalline (4) after 6 months. Among the isotropic samples, some of them became crystalline (1,5,6,10,13), while others remained amorphous (11,14,15) or became partial crystalline (4) after 6 months.…”

Constitutional Dynamic Materials—Toward Natural Selection of Function

“…70 In this process, the amount of chitosan and cinnamaldehyde components had an impact on the morphology of the resulted gels.…”