Lignin-reinforced photothermal polyurethane elastomers with tunable mechanics, shape memory, and antibacterial...

Area of Science:

• Materials Science
• Polymer Chemistry
• Biomaterials

Background:

• Balancing mechanical properties and multifunctionality in polyurethane elastomers is challenging.
• Lignin, a bio-based polymer, offers potential for developing sustainable materials.
• Developing high-performance, multifunctional elastomers from renewable resources is crucial.

Purpose of the Study:

• To develop a sustainable strategy for fabricating high-performance polyurethane elastomers (MEPU) using lignin derivatives.
• To integrate chemically modified lignin (MLOH) and enzymatic lignin (EL) to enhance mechanical and photothermal properties.
• To explore the tunable photothermal conversion and mechanical performance of MEPU by adjusting the MLOH/EL ratio.

Main Methods:

• Fabrication of MEPU by integrating MLOH (reactive crosslinker) and EL (physical crosslinker).
• Characterization of mechanical properties (tensile strength, elongation at break, toughness).
• Evaluation of photothermal conversion efficiency and NIR-triggered functionalities (shape memory, self-healing, antibacterial activity).

Main Results:

• MEPU exhibited tunable photothermal conversion and mechanical performance based on the MLOH/EL ratio.
• Optimal formulation M5E5PU showed exceptional mechanical properties (tensile strength 37.8 MPa, elongation at break 795.5%) and photothermal conversion (101.8°C).
• M5E5PU demonstrated NIR-triggered shape memory, fatigue resistance, self-healing, and complete antibacterial activity within minutes.

Conclusions:

• This work presents a novel platform for developing multifunctional, bio-based photothermal elastomers.
• The developed MEPU offers a sustainable approach for high-value utilization of lignin.
• The tunable properties and functionalities make MEPU suitable for various advanced applications.