Synthesis and characterization of cholesteric cellulose nanocrystals from cladophora rupestris

• Main Author: Sucaldito, Melvir R.
• Format: text
• Language: English
• Published: Animo Repository 2016
• Online Access: https://animorepository.dlsu.edu.ph/etd_masteral/5253
• Institution: De La Salle University

The study successfully synthesized and characterized cholesteric cellulose nanocrystals from Cladophora rupestris and cholesterol via click chemistry. The study consisted of six stages: extraction of cellulose from Cladophora rupestris, isolation of cellulose nanocrystals from cellulose, synthesis of the azide-bearing cellulose nanocrystals, synthesis of Opropargylcholesterol, synthesis of cellulose nanocrystals-cholesterol click product and characterization of the cellulosic samples. SEM and TEM revealed a web-like network of CNCs and its dimensions: 23.99 (4.85) nm for the diameter and 498 (114) for the length. XRD measurements showed 93.97% crystallinity for CNCs. FTIR and NMR spectroscopic methods were utilized to determine the structures of the products in several stages of synthesis. Thermogravimetric analysis demonstrated that CNCs have higher thermal stability than the crude cellulose. FTIR spectroscopy showed successful click reaction between O-propargylcholesterol and CNC. TEM revealed that CNCs were bounded occasionally by cholesterol on its surface. XRD measurements demonstrated lowered crystallinity (85.67%) for the click product.