Abstract
ABSTRACT In this study, based on the mechanical shear treatment, the cellulosic pulp was fibrillated in nanofibrils dispersed in aqueous suspension. Nanofibrillated Cellulose (NFC) matrix - Polyvinyl Alcohol (PVA) nanocomposite films’ were prepared by casting from NFC/PVA suspension mixtures. The thermal and mechanical properties of the obtained films were evaluated. Low levels (2, 5 and 10 wt%) of PVA were used as an additive in a nanofibrillated cellulose (NFC) matrix. The predominant use of NFC, with superior properties due to its purity, with an efficient and environmentally friendly method, has allowed the production of NFC-based biodegradable materials with enhanced properties for high-level applications. The addition of PVA to the NFC matrix produced positive results, as it causes little aesthetic interference, without changes in surface brightness. After the addition of PVA the films showed a great gain in mechanical strength, increasing by 24% in Young’s modulus with the addition of 10% PVA. Even after addition, the samples’ chemical composition remains unchanged and the mixture shows a decrease in the film surface hydrophilicity when compared to pure NFC. Composite material thermal analysis indicates that thermal degradation temperatures remain unchanged after the addition of PVA. Although PVA is not very temperature resistant, in the proportions used, NFC thermal resistance is preserved.
Highlights
A large number of living organisms can naturally produce high-performance extracellular structural biocomposites consisting of a fibrous reinforced matrix with biopolymers, for example, cellulosic fiber, a major component of hemp, wheat straw, rice straw, bagasse, wood
According to the evaluation of Fourier Transform Infrared Spectroscopy (FTIR) spectra, performed on 0.5% nanofibrillated cellulose (NFC) films containing polyvinyl alcohol (PVA), small changes in the material composition were observed, because the addition of PVA is at low concentrations in relation to the NFC material mass and the additive presence may not be detected by the technique
The spectroscopic profile is similar to that NFC except for two small signals that appeared in the sample containing 10% of PVA in its composition (1716 cm-1 due to the carbonyl present in the PVA and the other in 1258 cm-1 of PVA OH bonds), showing that the other concentrations were not detected by the analytical method
Summary
A large number of living organisms can naturally produce high-performance extracellular structural biocomposites consisting of a fibrous reinforced matrix with biopolymers, for example, cellulosic fiber, a major component of hemp, wheat straw, rice straw, bagasse, wood. Considerable interest is currently directed to the micro or nanofibrils of cellulose and its composites, due to its low-cost properties, biocompatibility, bioactivity, low toxicity, biodegradability, and oxygen barrier (SPOLJARIC et al, 2014; ABDUL KALIL et al, 2012). These particularities give them many potential applications, such as the controlled release of substances of interest, tissue engineering, food packaging, and reinforcement in materials (LU et al, 2017; XU et al, 2015; KISONEN et al, 2015; LENDLEIN; SISSON, 2011). In the case of low NFC content (less than 5% by weight), the results were expressive, indicating a good increase in mechanical resistance
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
