Abstract
The recognition of nanocellulose has been prominent in recent years as prospect materials, yet the ineffectiveness of nanocellulose to disperse in an organic solvent has restricted its utilization, especially as a reinforcement in polymer nanocomposite. In this study, cellulose has been isolated and defibrillated as cellulose nanofibrils (CNF) from oil palm empty fruit bunch (EFB) fibers. Subsequently, to enhance its compatibility with UV-curable polyurethane (PU)-based resin, the surface hydrophilicity of CNF has been tailored with polyethylene glycol (PEG), as well as reduced graphene oxide (rGO). The dispersibility of reinforced modified CNF in UV-curable PU was examined through the transmittance interruption of resin, chemical, and mechanical properties of the composite printed using the stereolithographic technique. Evidently, the enhanced compatibility of modified CNF and UV-curable PU was shown to improve the tensile strength and hardness of the composites by 37% and 129%, respectively.
Highlights
As the world’s second largest producer of palm oil products, Malaysia had an oil palm plantation area of 5.85 million hectares in 2017—an increase of 0.7% from the 5.81 million hectares in the previous year [1]
0.5 wt% of polyethylene glycol (PEG) 4000 was dissolved in ethanol solution and added to the cellulose nanofibrils (CNF) solution with reference to the CNF content, after which the mixture was homogenized using an homogenizer for 30 min (T 25 Ultra-Turrax, IKA, Staufen, Germany)
Washing was performed using a centrifugation technique, whereby the CNF solution was mixed with 10 wt% graphene oxide (GO) solution using homogenizer for 30 min (T 25 Ultra-Turrax, IKA, Staufen, Germany), after which NaBH4 was added to the CNF/GO mixture and heated at 80 ◦C for 60 min to yield CNF/reduced graphene oxide (rGO)
Summary
As the world’s second largest producer of palm oil products, Malaysia had an oil palm plantation area of 5.85 million hectares in 2017—an increase of 0.7% from the 5.81 million hectares in the previous year [1]. Oil palm EFB mainly consists of lignin, hemicelluloses, and cellulose, the last of which is the most abundant natural polymer worldwide [6]. Despite the fused deposition modelling (FDM)-based technique being widely used due to the inexpensive machine and materials, the quality of surface finish and mechanical properties of these printed materials are limited in comparison with other additive manufacturing techniques and typical manufacturing processes [11,12] Apart from this technique, stereolithography is the most common technique for the creation of a computer-designed virtual three-dimensional object to be “printed” into a solid object [13]. This study has attempted to determine the extent of improvement of the mechanical properties for UV-curable polyurethane (PU)-based 3D-printed products by enhancing the compatibility of CNF as a reinforced material in the resin composition. In-depth analysis of the chemical interactions between CNF, PU resin, and the modified CNF was performed and correlated with the tensile strength, Young’s modulus, and the hardness of the printed composites
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
