Design and Characterization of Sustainable PLA-Based Systems Modified with a Rosin-Derived Resin: Structure-Property...

Area of Science:

• Polymer Science
• Materials Science
• Sustainable Chemistry

Background:

• Developing sustainable polymer systems with tunable properties is crucial for advanced functional materials.
• Poly(lactic acid) (PLA) is a widely used bio-based polymer with potential for broader applications.
• Modified rosin resins offer a sustainable pathway to tailor polymer characteristics.

Purpose of the Study:

• To investigate the impact of a phenol-free modified rosin resin (Unik Print™ 3340, UP) on the properties of various poly(lactic acid) (PLA) grades.
• To evaluate how UP influences the structural, thermal, rheological, and mechanical behavior of PLA.
• To assess the potential of UP as a sustainable additive for enhancing PLA performance.

Main Methods:

• Melt compounding of four different PLA grades with 3 phr of UP.
• Thermogravimetric analysis (TGA) for thermal degradation assessment.
• Differential scanning calorimetry (DSC) for thermal transitions and crystallinity.
• Mechanical testing (tensile, toughness) and rheological measurements.
• Field Emission Scanning Electron Microscopy (FESEM) for microstructural analysis.

Main Results:

• UP did not compromise the thermal degradation stability of PLA.
• UP suppressed crystallization and melting in amorphous PLA and lowered crystallization temperatures in semi-crystalline grades.
• Toughness increased by over 25% across all PLA grades, reaching up to 60% in amorphous, low-molecular-weight PLA.
• Mechanical tests showed improved ductility, supported by FESEM observations.
• Rheological measurements indicated moderate viscosity changes.

Conclusions:

• Unik Print™ 3340 (UP) acts as an effective physical modifier for PLA, significantly enhancing toughness and ductility.
• UP allows for fine-tuning of PLA's structure-property relationships without sacrificing thermal stability.
• This study presents a sustainable approach to developing bio-based PLA systems with improved mechanical performance for potential biomimetic applications.