Enhanced performance and reprocessability in polypropylene-lignin blends through plasma treatment

Emanuela Bellinetto; Sofia Regoli; Ruggero Barni; Carmen Canevali; Oussama Boumezgane; Luca Zoia; Claudia Riccardi; Stefano Turri; Gianmarco Griffini

doi:10.1016/j.jobab.2025.01.003

Volume 10 Issue 2

May 2025

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Article Navigation > Journal of Bioresources and Bioproducts > 2025 > 10(2): 170-186

Emanuela Bellinetto, Sofia Regoli, Ruggero Barni, Carmen Canevali, Oussama Boumezgane, Luca Zoia, Claudia Riccardi, Stefano Turri, Gianmarco Griffini. Enhanced performance and reprocessability in polypropylene-lignin blends through plasma treatment[J]. Journal of Bioresources and Bioproducts, 2025, 10(2): 170-186. doi: 10.1016/j.jobab.2025.01.003

Citation:

Emanuela Bellinetto, Sofia Regoli, Ruggero Barni, Carmen Canevali, Oussama Boumezgane, Luca Zoia, Claudia Riccardi, Stefano Turri, Gianmarco Griffini. Enhanced performance and reprocessability in polypropylene-lignin blends through plasma treatment[J]. Journal of Bioresources and Bioproducts, 2025, 10(2): 170-186. doi: 10.1016/j.jobab.2025.01.003

Citation:

Emanuela Bellinetto, Sofia Regoli, Ruggero Barni, Carmen Canevali, Oussama Boumezgane, Luca Zoia, Claudia Riccardi, Stefano Turri, Gianmarco Griffini. Enhanced performance and reprocessability in polypropylene-lignin blends through plasma treatment[J]. Journal of Bioresources and Bioproducts, 2025, 10(2): 170-186. doi: 10.1016/j.jobab.2025.01.003

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Enhanced performance and reprocessability in polypropylene-lignin blends through plasma treatment

doi: 10.1016/j.jobab.2025.01.003

a. Department of Chemistry, Materials and Chemical Engineering "Giulio Natta", Politecnico di Milano, Milano 20133, Italy;
b. Department of Physics "Giuseppe Occhialini", Università degli Studi di Milano-Bicocca, Milano 20126, Italy;
c. Department of Materials Science, Università degli Studi di Milano-Bicocca, Milano 20125, Italy;
d. Department of Earth and Environmental Science, Università degli Studi di Milano-Bicocca, Milano 20126, Italy

Funds:

This work received funding from Regione Lombardia and Fondazione Cariplo (No. 2018-1739, Project: POLISTE), the European Union's Horizon 2020 Research and Innovation Programme (No. 952941, Project: BIOMAC), and Regione Lombardia (“Collaboration Agreement for the Creation of an Innovative Pilot Regional Infrastructure to Support the Transition Towards the Circular Economy”, Project: EcoCIRC Regional Hub). This study was partly carried out within the Agritech National Research Center funded by the European Union Next-GenerationEU (National Recovery and Resilience Plan (Piano Nazionale di Ripresa e Resilienza - PNRR) - Mission 4, Component 2, Investment line 1.4 - d.d. 1032 17/06/2022, cn00000022).

Available Online: 2025-05-09
Publish Date: 2025-01-20

Abstract

Abstract

In this work, a new compatibilization strategy for polypropylene-lignin blends was presented, which did not rely on the use of solvents or other chemicals. Soda lignin was subjected to plasma treatment in an argon atmosphere employing a gliding-arc-tornado reactor configuration. The effect of this process was evaluated using electron paramagnetic resonance spectroscopy, nuclear magnetic resonance spectroscopy, differential scanning calorimetry, and thermogravimetric analysis, evidencing significant chemical-structural modifications in lignin, including an increased concentration of phenoxy radicals (60%) and depletion of hydroxyl functionalities (35%). Polypropylene-lignin blends incorporating 5% (w/w), 10% (w/w), and 20% (w/w) of either pristine or plasma-treated lignin were then prepared by melt-blending in a twin-screw extruder, and their thermo-mechanical and rheological properties were investigated in detail. As a result of the plasma-induced modifications occurred in lignin, blends incorporating the plasma-treated material exhibited greater thermo-oxidative stability, more favorable viscoelastic response, significantly improved mechanical performance (137% and 294% strain at break for polypropylene (PP) containing 5% (w/w) and 10% (w/w) of treated lignin, respectively), and enhanced thermo-mechanical reprocessability (> 95% retention of yield strength and strain at break after re-extrusion). This work provided the first demonstration of the effectiveness of plasma treatment as a viable and sustainable strategy to improve filler-matrix interactions in polypropylene-lignin blends without the use of solvents, chemical compatibilizers or additional wet-chemistry steps, paving the way for the development of lignin-based thermoplastic polyolefin materials with enhanced thermo-mechanical characteristics and improved reprocessability.
- Lignin,
- Polypropylene,
- Plasma,
- Gliding arc tornado,
- Compatibilization

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References(82)

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