A cleaner processing approach for cellulose reinforced thermoplastic polyurethane nanocomposites. Issue 3 (26th January 2022)

• Record Type: Journal Article
• Authors: Mohd Amin, Khairatun Najwa; Chaleat, Celine; Edwards, Grant; Martin, Darren J.; Annamalai, Pratheep Kumar
• Is Part Of: Polymer engineering & science. Volume 62:Issue 3(2022)
• Page Start: 949
• Page End: 961
• Publication Date: 2022-01-26
• Subjects: cellulose nanocrystal (CNC) -- microcrystalline cellulose (MCC) -- nanocomposites -- reactive extrusion -- thermoplastic polyurethane; Polymer engineering -- Periodicals; Polymers -- Periodicals; 668.9
• DOI: 10.1002/pen.25899
• Languages: English
• ISSNs: 0032-3888

Abstract

Abstract: In a manner of addressing challenges in scalable processing of thermoplastic polyurethane (TPU) nanocomposites through extrusion methods, this study reports a very clean processing approach of incorporating cellulose nanocrystal (CNC) into a TPU matrix, with no acid or organic‐solvents usage. It involves a mechanical deconstruction of microcrystalline cellulose (MCC) into nanoscale particles in water and polyol through scalable bead‐milling, vacuum drying, and followed by twin‐screw reactive extrusion with isocyanate and chain extender. The thermal stability of CNC was higher than that of typically acid‐hydrolyzed CNC and suitable for processing with the precursors of TPU at typical processing temperature range (175–190°C). The CNC incorporation at very low loadings (0.5, 0.8 wt%) through this methodology resulted in substantial enhancements in tensile properties (for example, up to 28% in strength and toughness) without any significant stiffening effect. Moreover, the nanocomposites retained elastic properties, including elongation at break (%), resilience, and creep resistance. Their chemical properties and thermal transitions were also found to support the retained thermoplastic behavior while improving mechanical performance. Abstract : Acid and solvent‐free processing of TPU/Nanocellulose nanocomposites.