Biodegradable Poly(lactic acid)-Based Blends as Intrinsic Self-Healing Matrices for Multifunctional and...

Area of Science:

• Materials Science
• Polymer Science
• Composite Materials

Background:

• Developing biodegradable materials for advanced applications is crucial.
• Self-healing properties in polymers can extend material lifespan and reduce waste.
• Composite laminates require robust matrices with enhanced functionalities.

Purpose of the Study:

• To develop and characterize compatibilized poly(lactic acid)/poly(butylene adipate-co-terephthalate) (PLA/PBAT) blends.
• To evaluate the potential of these blends as biodegradable self-healing matrices for composite laminates.
• To determine the optimal PBAT content for balancing mechanical performance and self-healing efficiency.

Main Methods:

• Melt compounding and hot pressing were used to prepare PLA/PBAT blends with varying PBAT content (10-30%wt) and an epoxy-based compatibilizer.
• Rheological measurements, FT-IR, and FESEM analyses were conducted to characterize blend morphology and processability.
• Mechanical testing (tensile modulus, strength, fracture toughness) and self-healing efficiency evaluation (K_IC recovery) were performed.

Main Results:

• PLA/PBAT blends exhibited immiscible but well-compatibilized morphology with suitable viscosity for melt processing.
• Mechanical properties decreased with increasing PBAT content, but fracture toughness showed improvement after healing.
• The blend with 20%wt PBAT achieved 64% self-healing efficiency under impact conditions, attributed to effective PBAT phase flow during thermal treatment.

Conclusions:

• Compatibilized PLA/PBAT blends are viable biodegradable matrices for self-healing composite laminates.
• The 20%wt PBAT formulation offers the best compromise between mechanical integrity and self-healing capabilities.
• Optimized blend composition and morphology are key to achieving efficient self-healing in biodegradable polymer matrices.