Polyamide 6/modified pine bark particle composites for additive manufacturing

• Published in: Journal of materials science Vol. 56; no. 34; pp. 19093 - 19105
• Main Authors: Gama, Nuno, Ferreira, Artur, Barros-Timmons, Ana, Evtuguin, Dmitry
• Format: Journal Article
• Language: English
• Published: New York Springer US 01.12.2021; Springer; Springer Nature B.V
• Subjects: 3D printing; Bark; Biomass; Characterization and Evaluation of Materials; Chemistry and Materials Science; Classical Mechanics; Composite materials industry; Composites & Nanocomposites; Cross polarization; Crystallography and Scattering Methods; Ethylenediamine; Ethylenediamines; Fourier transforms; Glass transition temperature; Infrared spectroscopy; Materials Science; Modulus of elasticity; NMR; Nuclear magnetic resonance; Particulate composites; Polyamide resins; Polyamides; Polymer Sciences; Polyols; Solid Mechanics; Thermogravimetric analysis; Three dimensional printing; X ray analysis
• ISSN: 0022-2461; 1573-4803
• DOI: 10.1007/s10853-021-06443-7

Aiming the sustainability of 3D-printed objects, in this study, pine bark particles were used as filler reinforcement for polyamide 6 (PA). In order to enhance the performance of the produced composites, the biomass was chemically modified via a two-step procedure. In the first step, the OH groups present on the particles surface were reacted with ethylenediamine, which were subsequently reacted with a polyol. Fourier-transform infrared spectroscopy (FTIR), 13 C solid-state cross polarization–magic angle spinning nuclear magnetic resonance ( 13 C CPMAS NMR) and scanning electron microscopy coupled with energy-dispersive X-ray analysis confirmed the chemical modification of biomass. The masterbatch was prepared from modified pine bark particles and polymeric matrix (PA) being processed into test specimens. The ensuing composites revealed a significant increase in Young's modulus and maximum stress. Thus, the introduction of 10% modified biomass increases the Young's modulus by 87% and the maximum stress by 15%. Furthermore, analyzing the glass transition temperature ( Tg ), melting flow index and thermogravimetric analysis results, the modified biomass ensuing composites proved to be suitable for 3D printing. This was attributed to better compatibility between chemically modified biomass and matrix and, further, easier processing. Graphical abstract