De- and Re-Structuring of Starch to Control the Melt and Solid State Visco-Elasticity as Method for Getting New Multi...

Area of Science:

• Materials Science
• Polymer Chemistry
• Sustainable Materials

Background:

• Starch is a renewable resource but often limited by poor thermal stability and processability.
• Polyvinyl alcohol (PVA) is a water-soluble synthetic polymer with complementary properties to starch.
• Developing stable, melt-processable starch-based compounds is crucial for expanding their application range.

Purpose of the Study:

• To design and develop thermodynamically stable, melt-processable starch-based compounds.
• To achieve scalable properties for manufacturing via classic or 3D printing methods.
• To explore the relationship between miscibility, thermodynamic stability, and the lifetime of starch-PVA compounds.

Main Methods:

• A two-stage experimental sequence involving pre-treatment and melt compounding of starch and PVA.
• Modification of starch and PVA to enhance miscibility and thermodynamic stability.
• Characterization of viscoelastic properties under varying formulation and flow conditions.

Main Results:

• Achieved new starch-PVA compounds with high macromolecular miscibility and thermodynamic stability for at least 10 years.
• Developed compounds with glass transitions ranging from -10 °C to 50 °C.
• Demonstrated optimal processability for extrusion, injection molding, and 3D printing, along with good scalability.

Conclusions:

• The study successfully created stable, melt-processable starch-PVA compounds with extended durability.
• Understanding thermodynamic stability is key to utilizing starch in medium-life applications.
• These findings pave the way for broader applications of starch-based materials beyond short-life products.