Synthesis, characterization, and gas permeation properties of t-butylcarbamates of cellulose derivatives

Amino acid‐functionalized ethyl cellulose: Synthesis, characterization, and gas permeation properties

“…The results are summarized in Table 1. The DS E t of EC was estimated to be 2.69, by calculating the integration ratio of methyl protons to the rest of the protons in the 1 H NMR spectrum of EC, indicating the presence of 0.31 hydroxy groups per AGU 40, 42, 44, 45. The 1 H NMR spectral data of amino acid esters of EC ( 1 – 6 ) were obtained to determine the degree of substitution by ester group, namely aminoalkanoyl substituent, (DS E st ) by making an estimation of the peak intensity ratios of the terminal methyl protons of ethyl group of EC and those of t ‐Boc moieties of the amino acid pendants.…”

“…The hydroxy anchors of EC and the carboxy termini of amino acids provide an ample opportunity of bringing about a successful conjunction of the two biocompatible families of materials. Our previous efforts to effect the derivatization of organosoluble cellulosic polymers with a variety of substituents are quite evident of the fact that the tailoring of pendants on the cellulosic backbone results in a significant alteration of solubility, thermal, charge/discharge, and gas permeation characteristics as desired for specific applications 39–45. Hence, amino acid esterification of EC is anticipated to lead to the enhanced CO 2 separation performance, making these materials interesting candidates for gas separation membranes.…”

Preparation and High Performance of Cellulose Acetate Films by Grafting with Imidazole Ionic Liquid

“…Cellulose-based materials have become a necessary part of the gas separation because they have a moderate chain structure, high mechanical strength, and good flexibility. − All kinds of cellulose derivatives, such as ethyl cellulose (EC), cellulose acetate (CA), trifluoroacetylated cellulose, and silyl cellulose, have been prepared to be used for the gas separation film materials. − Of those film materials, CA was found to be the most suitable and most widely developed membrane material for gas separation and enrichment . As such, there is always a tradeoff between gas permeance and selectivity.…”

“…As such, there is always a tradeoff between gas permeance and selectivity. Surprisingly, gas separation performance of film materials could be realized by chemical or physical modification to change their microstructure, such as ionic liquids (ILs) as grafting agents and inorganic materials as additives, or by blending with other polymers in the CA polymeric matrix. − …”

Preparation of cellulose and pulp carbamates through a reactive dissolution approach

“…[1][2][3][4] In these reports the products were found to be applicable as regenerated cellulose bres via the CarbaCell process, where isocyanates are generated in situ from urea. [5][6][7][8] Other applications were as membrane materials, [9][10][11] chiral stationary phases for liquid chromatography, [12][13][14][15] derivatives used for the characterization of the molar mass distribution of cellulose, by size exclusion chromatography, [16][17][18][19] carpet cleaners, sponges and in the formation of lyotropic liquid crystals. 20 Cellulose carbamates can be produced from the reaction of cellulose with isocyanates either homogenously or in heterogeneous phase.…”