Injection Molding of Thermoplastic Cellulose Esters and Their Compatibility with Poly(Lactic Acid) and Polyethylene

Area of Science:

• Materials Science
• Polymer Science
• Sustainable Materials

Background:

• Growing environmental concerns drive demand for biobased polymers from renewable resources.
• Biobased polymers currently hold a small share of the global market.
• Cellulose esters often require plasticizers for thermoplastic processing.

Purpose of the Study:

• To investigate the injection molding of thermoplastic cellulose octanate (cellulose C8) and cellulose palmitate (cellulose C16).
• To analyze the mechanical properties and internal structure of processed cellulose esters.
• To evaluate the compatibility of cellulose esters with poly(lactic acid) (PLA) and biopolyethylene (bio-PE).

Main Methods:

• Injection molding of cellulose C8 and cellulose C16.
• Tensile testing for mechanical property analysis.
• Field emission scanning electron microscopy (FE-SEM) for structural analysis.
• Compounding experiments with PLA and bio-PE.

Main Results:

• Cellulose C8 and C16 demonstrated complete processability without plasticizers, a rare characteristic for cellulose esters.
• Compounding cellulose esters with PLA enhanced blend elongation and reduced density.
• FE-SEM revealed the internal structure of the injection-molded objects.

Conclusions:

• Thermoplastic cellulose esters are viable for plasticizer-free injection molding.
• Cellulose esters show promising compatibility with PLA, improving key properties.
• These fully biobased materials hold significant potential for future injection molding applications.