Optimizing the lignin nanoparticles from different pulping by-products in developing cotton-based nanocrystalline...

Area of Science:

• Materials Science
• Biotechnology
• Polymer Science

Background:

• Conventional inorganic UV shielding agents pose biotoxicity and spectral coverage limitations.
• Sustainable and non-toxic alternatives are crucial for advanced material applications.
• Lignin, an abundant biopolymer, presents an opportunity for developing eco-friendly UV protective materials.

Purpose of the Study:

• To develop novel bio-based UV-shielding nanocomposites using lignin nanoparticles (LNPs) derived from rice straw.
• To investigate the efficacy of LNPs incorporated into nanocrystalline cellulose (CNC) matrices for UV protection.
• To explore the potential of valorizing industrial lignin waste into high-performance UV protective materials.

Main Methods:

• Lignin nanoparticles (LNPs) were extracted from rice straw black liquor via acid precipitation and solvent exchange (THF/EG).
• LNPs were incorporated into nanocrystalline cellulose (CNC) matrices to create bio-based nanocomposites.
• Nanoparticles and composites were characterized using TEM, ATR-FTIR, XRD, AFM, and POM.

Main Results:

• Nanocomposites achieved up to 99.9% UV shielding in UVC and UVB regions with increasing LNP loading (1-5 wt%).
• CNC-LNP composites demonstrated nearly complete UVA protection, particularly those derived from Kraft (LNPT7) and KOH/NH₄OH (LNPE6) pulping.
• LNPE6 particles were semi-spherical (23.8 nm), while LNPT7 particles were spherical (524.6 nm), influencing composite properties.

Conclusions:

• Valorization of industrial lignin waste can yield effective, eco-friendly UV-protective materials.
• The developed CNC-LNP nanocomposites offer a sustainable alternative to conventional UV shielding agents.
• These bio-based materials show promise for applications in packaging, personal care, and optical devices.