The potential of nanofibrillated cellulose from Hevea brasiliensis to produce films for bio-based packaging.

Cellulose micro/nanofibril (MNFC) films are an interesting alternative to plastic-based films for application in biodegradable packaging. In this study, we aimed to produce and characterize MNFC films obtained from alkaline-pretreated rubberwood (Hevea brasiliensis) waste and Eucalyptus sp. commercial pulp.

Impact of accelerated aging cycles on the performance of extruded cement-based composites reinforced with non-bleached eucalyptus fibers.

Thermo-mechanical pulping produces well-individualized fibers compared to wood particles and less fragile fibers compared to Kraft pulping, besides presenting higher volume, higher yield, and lower production cost, which can be an exciting alternative for the fiber-cement industries. This study evaluated the impact of soak and dry-aging cycles on the performance of extruded composites reinforced with non-bleached eucalyptus fibers. The cement matrix comprised cement (70%) and limestone (30%).

Potential of NIR spectroscopy for predicting cellulose nanofibril quality in commercial bleached Kraft pulp of Eucalyptus.

Multivariate models were developed to classify cellulose nanofibril (CNF) fibrillation by a quality index from near infrared (NIR) spectra. Commercial pulps of Eucalyptus spp. were used to produce cellulose nanofibrils by means of a fibrillator mill.

Developing a Biodegradable Film for Packaging with Lignocellulosic Materials from the Amazonian Biodiversity.

The development of packaging films made from renewable raw materials, which cause low environmental impact, has gained attention due to their attractive properties, which have become an exciting option for synthetic films. In this study, cellulose micro/nanofibrils (MFC/NFC) films were produced with forest residues from the Amazon region and evaluated for their potential to generate alternative packaging to traditional plastic packaging. The MFC/NFC were obtained by mechanical fibrillation from fibers of açaí seeds (), titica vine (), and commercial pulps of sp.

Effect of different pre-treatments on the redispersion capacity of spray-dried microfibrillated cellulose: Elaboration and characterization of biofilms.

This study aimed to evaluate the influence of the addition of the cationic surfactant cetyltrimethylammonium bromide (CTAB) in microfibrillated cellulose (MFC/CNFs) suspensions submitted to different pretreatments to produce redispersible spray-dried (SD) MFC/CNFs. Suspensions pretreated with 5 % and 10 % sodium silicate and oxidized with 2,2,6,6,-tetramethylpiperidinyl-1-oxyl (TEMPO) were modified with CTAB surfactant and subsequently dried by SD. The SD-MFC/CNFs aggregates were redispersed by ultrasound to produce cellulosic films by the casting method.

Mandacaru cactus as a source of nanofibrillated cellulose for nanopaper production.

In this work, nanofibrillated cellulose (NFC) was extracted from cactus Cereus jamacaru DC. (mandacaru) for nanopaper production. The technique adopted includes alkaline treatment, bleaching, and grinding treatment.

Comparison of pre-treatments mediated by endoglucanase and TEMPO oxidation for eco-friendly low-cost energy production of cellulose nanofibrils.

Specific kinds of enzymes have been used as an eco-friendly pre-treatment for mechanical extraction of cellulose nanofibrils (CNFs) from vegetal pulps. Another well-established pre-treatment is the 2,2,6,6-tetramethylpiperidine 1-oxyl (TEMPO)-mediated oxidation, which has gained considerable attention. Pre-treatments assist in fiber swelling, facilitating mechanical fibrillation, and reducing energy consumption; however, some of these methods are extremely expensive.

Influence of hemicellulose content and cellulose crystal change on cellulose nanofibers properties.

This study aimed to evaluate the properties of cellulose nanofibers (CNFs) with different hemicellulose contents and cellulose II polymorphs. A link was found between these polysaccharides and the properties of CNFs. A decrease in crystallinity (from 69 to 63%) and changes in the crystalline structure of cellulose subjected to an alkaline environment were observed, promoting the partial conversion of cellulose I to cellulose II (from 2 to 42%) and preventing CNFs production at NaOH concentrations higher than 5%.

Copaiba oil and vegetal tannin as functionalizing agents for açai nanofibril films: valorization of forest wastes from Amazonia.

The applicability of cellulose nanofibrils (CNFs) has received attention due to their attractive properties. This study proposes the functionalization of açai CNFs with copaiba oil and vegetal tannins to produce films with potential for packaging. Bio-based films were evaluated by vapor permeability, colorimetry, and mechanical strength.

Eco-friendly laccase and cellulase enzymes pretreatment for optimized production of high content lignin-cellulose nanofibrils.

Lignin-cellulose nanofibrils (LCNF) are of attracting an increasing interest due to the benefits of maintaining the lignin in the nanomaterial composition. The production of LCNF requires considerable energy consumption, which has been suppressed employing pretreatment of biomass, in which it highlights those that employ enzymes that have the advantage of being more environmentally friendly. Some negative aspects of the presence of lignin in the fiber to obtain cellulose nanofibrils is that it can hinder the delamination of the cell wall and act as a physical barrier to the action of cellulase enzymes.

Bio-based films/nanopapers from lignocellulosic wastes for production of added-value micro-/nanomaterials.

The growing demand for products with lower environmental impact and the extensive applicability of cellulose nanofibrils (CNFs) have received attention due to their attractive properties. In this study, bio-based films/nanopapers were produced with CNFs from banana tree pseudostem (BTPT) wastes and Eucalyptus kraft cellulose (EKC) and were evaluated by their properties, such as mechanical strength, biodegradability, and light transmittance. The CNFs were produced by mechanical fibrillation (after 20 and 40 passages) from suspensions of BTPT (alkaline pre-treated) and EKC.

Redispersion and structural change evaluation of dried microfibrillated cellulose.

Commercializing dried microfibrillated cellulose (MFC) has always been a challenge mainly due to the tendency of MFC to aggregate. In this study MFC samples were submitted to drying/redispersion cycles at different temperatures. Morphology, crystallinity and mechanical performance of films were analyzed throughout the cycles.

Artificial neural network and partial least square regressions for rapid estimation of cellulose pulp dryness based on near infrared spectroscopic data.

The content of water in fiber suspension and affects pulp refining, bleaching and draining operations. Cellulose pulp dryness estimate through near infrared (NIR) spectroscopy coupled with multivariate regressions or artificial neural network (ANN) techniques are not well explored yet. In this study models were developed to estimate cellulose pulp dryness in pads based on the NIR spectra.

Study of morphological properties and rheological parameters of cellulose nanofibrils of cocoa shell (Theobroma cacao L.).

Cocoa shell was evaluated as a precursor for cellulose nanofibrils (NFCs) using mechanical defibrillation. Its morphology was analysed using optical microscopy and scanning electron microscopy with field emission. Rheological and mechanical behaviour were evaluated through flow curves with a strain rate ranging from 0 to 300 s at 25 °C and by means of oscillatory frequency sweeps (0.

Renewable hybrid nanocatalyst from magnetite and cellulose for treatment of textile effluents.

A hybrid catalyst was prepared using cellulose nanofibrils and magnetite to degrade organic compounds. Cellulose nanofibrils were isolated by mechanical defibrillation producing a suspension used as a matrix for magnetite particles. The solution of nanofibrils and magnetite was dried and milled resulting in a catalyst with a 1:1 ratio of cellulose and magnetite that was chemically and physically characterized using light, scanning electron and transmission electron microscopies, specific surface area analysis, vibrating sample magnetometry, thermogravimetric analysis, Fourier transform infrared spectroscopy, X-ray diffraction, catalytic potential and degradation kinetics.

Evaluation of reaction factors for deposition of silica (SiO₂) nanoparticles on cellulose fibers.

This study aimed to evaluate reaction conditions for deposition of SiO2 nanoparticles on the surface of cellulose fibers and their influence on moisture adsorption of the hybrid organic-inorganic material formed. SiO2 nanoparticle deposition was carried out with the sol-gel process testing four reaction times (2, 12, 18, and 24h) and three contents of the tetraethyl-orthosilicate (TEOS) precursor (1.9, 4.