Castor Oil-Based Polymer Films with Superior Mechanical, Thermal, and Optical Properties

Area of Science:

• Materials Science
• Polymer Chemistry
• Sustainable Materials

Background:

• Growing demand for sustainable alternatives to petroleum-based polymers.
• Need for high-performance biobased films for diverse applications.
• Castor oil (CO) as a renewable feedstock for polymer synthesis.

Purpose of the Study:

• To develop high-performance biobased polymer films from castor oil (CO).
• To investigate the structure-property relationships of CO-based films.
• To explore the potential of these films in sustainable applications.

Main Methods:

• Three-step synthesis: polymerization of styrene and maleic anhydride to poly(styrene-alt-maleic anhydride) (SMA), esterification of SMA with CO to create SMA-grafted CO (SMA-g-CO), and solution-blending/casting of SMA-g-CO with poly(ethylene glycol) (PEG).
• Optimization of film properties by varying molecular weights of SMA and PEG, CO grafting amount, and SMA-g-CO/PEG feed ratio.
• Systematic characterization of microstructure, mechanical, thermal, optical, toxicity, and solvent resistance properties.

Main Results:

• Successfully prepared CO-based films with up to 63.4 wt% biomass content.
• Achieved excellent tensile strength (up to 70 MPa) and high glass transition temperature (up to 184.2 °C).
• Demonstrated good mechanical performance retention after reprocessing, stable photoluminescence, UV-shielding, and visible light transmission.

Conclusions:

• Effective conversion of renewable castor oil into high-performance SMA-g-CO/PEG films.
• Films exhibit promising properties for applications supporting a circular economy.
• This work contributes to the development of sustainable polymer solutions.