Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
Results
Showing 1 to 17 of 17 for “"Cellulose esters"”.
-
Novel cellulose esters
Research in cellulose esters in recent years has concentrated on creating a variety of novel esters with a wide range of thermal and mechanical properties. These cellulose derivatives can be used for membranes, coatings, polymer blends, and other products. Novel cellulose solvent systems …
-
Regioselective Synthesis of Cellulose Esters
Cellulose is an extraordinarily abundant polymer that can be harvested and purified from trees and other renewable sources. Cellulose derivatives have been widely used as coatings, optical films, fibers, molded objects, and matrices for controlled release. The properties of cellulose derivatives …
-
Regioselective chlorination of cellulose esters
Chemical modification of cellulose has been of growing interest, owing to the abundance and processing challenges of natural cellulose. To date, etherification and esterification are the most effective strategies to modify physicochemical properties of cellulose and append new functionalities. …
-
Structure-property relationships of novel cellulose esters
Cellulose “waxy” (long-chain aliphatic) tri-esters of lauric (C₁₂), myristic (C₁₄), stearic (C₁₈), and eicosanoic (C₂₀) acids; mixed esters of lauric and acetic acids; and fluorinated mixed esters of 2,2,2-trifluoroethoxyacetic (TFEA) and acetic acids were synthesized in homogeneous DMAc/LiCl …
-
Characterization of cellulose esters via GPC/FT-IR
… determination of the degree of substitution of cellulose esters. The focus of the effort was on the application of a Fourier transform infrared spectrometer (FT-IR) as an in-line detector for quantitative gel permeation chromatography (GPC). GPC/FT-IR has been used in the analysis of polymeric …
-
Chemical Modification of Cellulose Esters for Oral Drug Delivery
… of the polymer. Functionalization of cellulose esters and ethers has been under extensive investigation for applications including drug delivery, cosmetics, food ingredients, and automobile coating. In oral delivery of poorly water-soluble drugs, amorphous solid dispersion (ASD) …
-
Cellulose Esters and Cellulose Ether Esters for Oral Drug Delivery Systems
… and consequently poor drug bioavailability. Cellulose ω-carboxyesters were designed and synthesized specifically for ASD preparations in Edgar lab that can meet the ASD expectations such as high Tg, recrystallization prevention and pH-triggered release due to the free -COOH groups. Rifampicin …
-
Regioselective Synthesis of Novel Cellulose Derivatives for Drug Delivery
… the regioselective synthesis of new classes of cellulose derivatives with properties that could help improve the delivery of pharmaceutical drugs within the human body. The specific synthetic targets of this research were regioselectively carboxylated and regioselectively aminated cellulose …
-
Synthesis and Applications of Cellulose Derivatives for Drug Delivery
In an effort to produce new derivatives of cellulose for drug delivery applications, methods were developed to regioselectively modify C-6 halo cellulose esters to produce cationic derivatives via nucleophilic substitution. Reaction of C-6 substituted bromo and iodo cellulose with trialkylated …
-
Cellulose-based fibers from liquid crystalline solutions
Solutions of cellulose esters with different concentrations in dimethylacetamide (DMAc) and with different types of substituents were studied in relation to their liquid crystalline (LC) solution behavior. Classical LC behavior was revealed for all solutions. Critical polymer concentration …
-
Regioselective Design of Polysaccharide Ester Graft Copolymers
… polyglucopyranoses such as amylose and cellulose, is difficult due to the similar reactivities of pendant hydroxy groups. One distinct structural feature of amylose and cellulose is the sole primary hydroxy group located at the C6 position of each monosaccharide. The increased steric …
-
Amorphous solid dispersion effects on in vitro solution concentrations of quercetin
… into amorphous solid dispersions (ASDs) with cellulose derivatives, eliminating crystallinity, and selectively releasing amorphous quercetin under simulated intestinal conditions (pH 6.8, 37C). Amorphous quercetin was dispersed in cellulose esters including 6-carboxycellulose acetate butyrate …
-
Regioselective Synthesis of Glycosaminoglycan Analogs
… biological roles and biosynthesis modulation. Cellulose is an abundant and renewable natural polymer. Applications of cellulose and cellulose derivatives have drawn increasing attention in recent decades. Chemical modification is an efficient method to append new functionalities to the …
-
Smart Surfaces in Biobased Materials
The self-assembly blends of cellulose propionate (CP) and fluorine (F)-containing cellulose derivatives was examined on a model system of solvent cast films. The F-containing derivatives were either high molecular weight statistical cellulose esters with a number of F-containing substituent evenly …
-
Design and Synthesis of Cellulose Ether Derivatives for Oral Drug Delivery
Chemical modification of naturally occurring cellulose into ester and ether derivatives has been of growing interest due to inexhaustible cellulose resources, and to excellent properties and extremely broad applications of these derivatives. However, traditional esterification and etherification …
-
Mixed Polysaccharide Esters for Amorphous Solid Dispersion Oral Drug Delivery Vehicles
… derivatives for oral drug delivery applications. Cellulose and cellulose esters have been extensively studied and utilized for different applications such as separation membranes, sustainable plastics, and enteric coatings in oral drug delivery carriers. We sought to exploit the ring-opening of …