Synthesis and Characterization of Functional Cellulose-Ether-Based PCL- and PLA-Grafts-Copolymers

Area of Science:

• Polymer Chemistry
• Materials Science
• Biomaterials

Background:

• Biodegradable materials like cellulose and polyesters offer sustainable alternatives but require modification for enhanced properties.
• Controlling copolymer molecular structure and composition is key to tailoring material performance.

Purpose of the Study:

• To synthesize and characterize cellulose-based graft copolymers with precise molecular composition and architecture.
• To investigate the regioselective modification of cellulose for creating macroinitiators.
• To explore the properties of resulting graft copolymers with polylactic acid (PLA) and polycaprolactone (PCL) segments.

Main Methods:

• Regioselective protection of cellulose's 6-OH group using trityl chloride.
• Alkylation and deprotection to yield 2,3-di-O-alkyl cellulose macroinitiators.
• Ring-opening polymerization of L-lactide or ε-caprolactone catalyzed by Sn(Oct)2.
• Characterization using FTIR, NMR, SEC, XRD, and DSC.

Main Results:

• Successfully synthesized cellulose-graft-PCL and cellulose-graft-PLA copolymers with controlled architecture.
• Cellulose-graft-PCL copolymers showed a melting point and up to 47% crystallinity.
• Cellulose-graft-PLA copolymers were amorphous with no discernible melting or crystallization points.

Conclusions:

• Regioselective modification enables precise control over cellulose-based graft copolymer synthesis.
• The resulting copolymers possess distinct thermal and structural properties based on the grafted polymer segment.
• This approach offers a pathway to design biodegradable materials with tunable properties for specific applications.