abstract
Aiming to produce high-quality bio-based 3D printed products, in this work, coconut fibers were chemical modified using caprolactone. Fourier-transform infrared spectroscopy (FTIR) and nuclear magnetic reasonance (NMR) confirmed the grafting of the hydroxyl groups present on the surface of the fibers with caprolactone units. Furthermore, from contact angle (CA) analyses, the higher hydrophobicity of fibers after chemical treatment was confirmed, which improved its affinity with PP. The enhanced filler/matrix compatibility was reflected on the mechanical performance and processability of the ensuing composites. The modified fibers derived composites showed higher stiffness and higher melting flow index (MFI), when compared to the untreated counterparts. The composites were used to produce 3D printed specimens. Smother filaments were obtained using modified fibers, which confirms the better compatibility of fibers/PP. The surface of the 3D printed composite specimen produced using treated fibers, presented smooth surface, similar to the PP. This observation highlights the enhancement of the 3D printing quality due to the chemical modification of fibers.
keywords
THERMAL CHARACTERIZATION; MECHANICAL-PROPERTIES; POLYMER COMPOSITES; POLYPROPYLENE; BEHAVIOR; BLENDS; DENSITY
subject category
Engineering; Materials Science
authors
Gama, N; Magina, S; Barros-Timmons, A; Ferreira, A
our authors
Ana Margarida Madeira Viegas de Barros Timmons
Associate Professor
Artur Jorge Faria Ferreira
Professor Coordinator
Nuno Vasco da Costa Gama Batista de Melo
Junior Researcher
Sandra Pereira Magina
ResearcherProjects
CICECO - Aveiro Institute of Materials (UIDB/50011/2020)
acknowledgements
This work was developed within the scope of the project CICECO-Aveiro Institute of Materials, UIDB/50011/2020 and UIDP/50011/2020, financed by national funds through the Portuguese Foundation for Science and Technology/MCTES. The NMR spectrometers are part of the National NMR Network (PTNMR) and are partially supported by Infrastructure Project No 022161 (co-financed by FEDER through COMPETE 2020, POCI and PORL and FCT through PIDDAC). Sandra Magina acknowledges FCT for the PhD grant SFRH/BD/121275/2016.