A comparative study of greener alternatives for nanocellulose production from sugarcane bagasse

Use of enzyme for extraction of nanocellulose from sugarcane bagasse is greener alternative. Literature indicates that effectiveness of these enzymes can be improved by auxiliary enzymes or mediators. In the current study, extraction of nanocellulose using laccase with these moderators, auxiliary enzyme glucose oxidase and mediator molecule, ABTS [2,2′-azinobis(3-ethylbenzthiazoline-6-sulfonate)] individually was done. Cellulose and lignin content, FT-IR, TGA and DSC analysis, XRD, SEM and PSA were done. Enzyme moderators improved the performance of laccase in lignin degradation. Lignin and cellulose content, crystallinity were used as parameters to optimize the concentrations, which was found to be ABTS (at 1.4 mM) and glucose oxidase (at 0.15 mg ml−1). At the optimal concentration, nanocellulose was extracted. Properties of nanocellulose obtained from both routes were compared. Size analysis revealed 339 nm and 636 nm for nanocellulose obtained with glucose oxidase and ABTS, respectively. Defibrillation was better in the case of the former one as seen from SEM. Graphical Abstract

A fabrication and characterization of luffa/PANI/PEO biocomposite nanofibers by means of electrospinning

Purpose This paper aims to address the production of biocomposite nanofibers using luffa natural fibers and polyaniline conductive polymer/polyethylene oxides (PANI/PEO). Design/methodology/approach In this study, luffa natural fibers are extracted by chemical method. After mixing the treated luffa (TL) with the PANI/PEO solution, TL/PANI/PEO nanofibers were produced by electrospinning (ES) method under different ES parameters to examine the optimal conditions for nanofiber production. Then TL/PANI/PEO biocomposite nanofibers prepared in different weight ratios were produced to analyze the effects of luffa in the morphology and thermal properties of the biocomposite nanofibers. The characterization analysis of TL/PANI/PEO biocomposite nanofibers was performed by scanning electron microscopy, Fourier transform infrared spectroscopy (FTIR) and differential scanning calorimetry (DSC) analysis methods. Findings The analysis shows that different weight ratios of TL to PANI/PEO changed the morphology of the membrane. When increasing the weight ratio of TL, the morphological structure of TL/PANI/PEO transformed from nanofiber structure to thin film structure. The appearance of O—H peaks in the FTIR results proved the existence of TL in PANI/PEO nanofibers (membrane). Moreover, an increase in the weight ratio of luffa from 2% to 7.5% leads to an increase in the peak intensity of the O—H group. Regarding DSC analysis, biocomposite nanofibers improved the thermal properties. According to all results, 2%wt TL/PANI/PEO showed optimal morphological properties. Originality/value Plant cellulose was extracted from the luffa, one of the natural fibers, by method of alkali treatment. A new type of biocomposite nanofibers was produced using TL blend with PANI via electrospinning method.

Thermophysical and structural properties of manganese ferrite nanoparticles

This paper discusses the results of the research carried out to study the structure, optical properties and thermophysical properties of a sample (nanopowder with a true density of 4.96 g/cm3, a particle size of 60 nm and a purity of 98.5%, SkySpring Nanomaterials, USA) with high purity. Based on the results of X-ray diffraction, the crystalline phase of MnFe2O4 ferrite nanoparticles was completely obtained and the values of the lattice parameters were determined. The results of the MID-IR analysis showed that the absorption coefficient [Formula: see text] reaches its maximum value at 748 cm[Formula: see text] wave number. The optical properties of the as-prepared nanostructures were also investigated by VERTEX 70 V diffuse reflectance spectroscopy (DRS). As can be seen from the results of the DSC analysis, the effects occurring in the temperature range up to [Formula: see text]C clearly reflect the nature of the phase transitions and the amount of energy generated in the ferrite samples.

Vegetable Oil-Based Resins Reinforced with Spruce Bark Powder and with Its Hydrochar Lignocellulosic Biomass

A bio-based polymeric matrix was developed by the copolymerization of a vegetable oil-based epoxy, epoxidized linseed oil (ELO), with dodecenyl succinic anhydride (DDSA). To obtain eco-friendly bio-composites, this matrix was combined with a natural filler: spruce bark powder (SB) with its hydrochar (HC) in various proportions ranged from 1 to 30 wt.%. The reactivities of these formulations were studied by DSC analysis that highlighted that both fillers have a high catalytic effect on the ELO–DDSA crosslinking reaction. The complementary studies by TGA, DMA, tensile tests, water absorption and Shore tests had shown that both HC and SB bring improvements to the mechanical properties of the composites, fulfilling multiple roles: (i) Both act as co-reactants in the copolymerization mechanism; (ii) HC acts as reinforcement, consolidating the network and providing stiffness and rigidity; and (iii) SB acts as plasticizer for reducing the brittle character of the epoxy resins.

Modulation of the PLLA Morphology through Racemic Nucleation to Reach Functional Properties Required by 3D Printed Durable Applications

This paper presents an alternative means for enhancing the durability of poly (L-lactide) (PLLA) by racemic nucleation following stereo-complexation with a selected poly (D-lactide) (PLDA). The compounds are obtained by melt blending of a PLLA grade, previously designed for 3D printing but with a low heat deflection temperature and impact resistance, with grades of PLDA differing in their molecular weight (Mw), D-lactide content (DS) and concentration. Our method considered how to reveal the racemic nucleation caused by stereo-complexation and its influence on functional properties. The FTIR study we performed showed that, depending on Mw, DS and concentration of the stereo-complexer (PDLA) used, bigger or smaller spectral changes can occur. The stereo-complexation was confirmed by the DSC analysis and, for the selected compound, by the POM, SEM, AFM microscopies, functional property and shapeability as 3D printing filaments. All the obtained results sustain the idea that, if a PLLA with Mw of 4.5 × 104 g·mol−1 is modified with PDLA with a medium Mw of 11.6 × 104 g·mol−1, medium DS of 4% and 1% concentration, a racemic nucleation is possible. It produces a racemic polylactic acid (PDLLA) with improved durability and good shapeability as 3D printing filaments. These results are explicable if the dependence of the intermolecular interactions appears between the PLLA and stereo-complexer PDLA. To enlarge the durable applicability of racemic polylactic acid (PDLLA), future research should identify other parameters controling the PLA stereo-complexing as the intensifying the mobility of the macromolecules, the finding of the optimal recemic cristalization window.

Impact of heating temperatures on the properties of instant cassava flour

Native cassava flour can be modified to be instant flour by heating the cassava flour in ethanol solution. The impact of heating temperatures of 60, 80, and 100 °C (coded as ICF-60, ICF-80, and ICF-100) on the properties of instant cassava flour (ICF), including colour, morphological, and thermal properties, water absorption, and solubility indexes and pasting behaviour, were investigated. Results showed that ICF produced at higher temperatures exhibited lower lightness, higher redness, and yellowness values. ICF-60 and ICF-80 still displayed the granular forms and birefringence properties of native starches, while granules of ICF-100 were broken and partially lost their birefringence properties. Results of X-ray diffraction (XRD) technique and differential scanning calorimetry (DSC) analysis suggested that the amylopectin double helixes of crystalline regions within the structure of ICF orientated to more perfect conformation before they were disrupted at the highest heating temperature (100 °C). During hydration, the starch granules of ICF-60 and ICF-80 absorbed water into their granules; meanwhile, ICF-100 entrapped water within the matrix formed by the entanglements of ICF-100 particles. Results of pasting behaviour analysis indicated that ICF-60 and ICF-80 showed better thermal stability while ICF-100 exhibited the highest cold viscosity.

A study of Thermal Decomposition and Kinetic Evaluation of Boron blended Flash Powder Composition

Herein, the thermal characteristics of flash powders of different combinations of Potassium Nitrate, Sulphur, Aluminium and Boron are reported. From the literature, it is identified that Boron implements lack of sensitiveness to flash powder mixture, which promotes the safety during the manufacturing process. But the thermal behaviour of the Boron blended compositions remain a mystery. Hence, various combinations of flash powder compositions are prepared by keeping the % of KNO3 and % of S as constant, and gradually 23% of Aluminium is reduced (23% to 0) by increasing the quantity of Boron (0 to 23%) in 19 trials, and are subjected to TGA/DSC analysis individually. The TGA and the DSC analysis reveals that the 65.65% replacement of Aluminium with Boron mixture shows predominant characteristics which is suitable for fireworks. Also, the reaction kinetics and the critical ignition temperature are calculated for the optimum composition. The performance of the fireworks product is checked with varying quantity to meet out the optimum quality.

Encapsulation of Cinnamic Acid on Plant-Based Proteins: Evaluation by HPLC, DSC and FTIR-ATR

Plant-based protein matrices can be used for the formulation of delivery systems of cinnamic acid. Pumpkin, pea and almond protein matrices were used for the formulation of dried complexes. The matrices were used in varying amounts (1%, 2%, 5% and 10%) whilst the amount of cinnamic acid was maintained constant. The obtained complexes were analyzed by HPLC, DSC and FTIR-ATR. The highest amounts of cinnamic acid were determined on complexes prepared by the lowest amounts of protein matrices, regardless of their type. The highest affinity for cinnamic acid adsorption was determined for the pumpkin protein matrix. DSC analysis revealed that adsorption of cinnamic acid caused an increase in the thermal stability of the almond protein matrix, while the other two matrices had the opposite behavior. The complexation of protein matrices and cinnamic acid was proven by recording the IR spectra. The obtained complexes could have potential applications in food products to achieve enrichment with cinnamic acid as well as proteins.

Evaluation of Microalgae’s Plastic Biodeterioration Property by a Consortium of Chlorella sp. and Cyanobacteria sp.

Malaysia is one of the top eight countries that has a drawback of mismanaged plastic waste. This study intended to investigate polymer degradation using the biological technique with the help of microalgae to minimise the time required for biodegradation. This research article aims to identify the collected sample with the most suitable microalgae for the biodegradation of microplastic and to analyse the biodegradation of the polymer by microalgae. The results revealed that the consortium of Chlorella sp. and Cyanobacteria sp. were able to deteriorate low-density polyethene (LDPE sample) through several stages, and this was confirmed by UV-Spec, FESEM, EDX, CHNO, FTIR and DSC analysis. The results obtained revealed that microalgae producing exopolysaccharides (EPS) decreased the carbon and oxygen ratio. According to SEM micrographs, microalga may colonise, agglomerate, and adhere microplastics to its surface, regardless of its fractional size. The EDX analysis showed that the initial composition of carbon was 92.30 ± 1.23 %, while after the incubation, the carbon composition started decreasing from 53.18 % to 39.12 ± 1.08 %. Finally, there was a 37.91 % decrease in carbon weight from elemental analysise

NIR spectroscopy coupled with multivariate data analysis in the prediction of the characteristics of mannitol lyophilized cakes

Mannitol is used in freeze-dried products as a bulking agent, consistency enhancer, or stabilizer, having the lowest hygroscopicity among the excipients commonly used as consistency agents, therefore it can be used in the formulation of unstable preparations. Lyophilization is a complex method of drying a solution at low temperature and low-pressure that addresses especially thermolabile substances, such as proteins. The end-product is a lyophilized powder, which can be administered parenterally after reconstitution with suitable solvents. The objective of this study was to evaluate freeze-dried products obtained from mannitol solutions of different concentrations. Mannitol solutions of increasing concentrations of 2.5%, 5%, 7.5%, and 10% were prepared by dissolving mannitol in distilled water. The prepared solutions were freeze-dried after a preliminary DSC analysis, in which the thermal phenomena that occurred during lyophilization were identified. Freeze-dried preparations were analyzed by different methods: macroscopic analysis by visual assessment and comparison with data from the literature, texture analysis by which several properties of these preparations were studied (hardness, deformation, mechanical work, adhesive strength, fracture resistance, and the number of fractures), evaluation of reconstitution time and porosity. The mannitol used in the lyophilization process, being partially amorphous, required differential calorimetric analysis to establish its glass transition and to avoid the collapse of the preparations during lyophilization. Finally, NIR spectroscopy was used to predict the characteristics of the freeze-dried powders in a non-invasive manner, without prior sample preparation.