Search Results (163)

Microcrystalline cellulose (MCC) possesses important attributes, including high crystallinity, a large surface area, excellent mechanical strength, chemical stability, and biodegradability. This study aims to research MCC extraction from bamboo (Phyllostachys edulis (Carrière) J. Houz.) fiber by assessing the impact of key processing variables such as acid concentration, temperature, and hydrolysis duration. Experimental results indicate that hydrolysis time and hydrochloric acid (HCl) concentration significantly influence yield. After evaluating the effects of various hydrolysis conditions, the optimal parameters were determined to be a 2.0 M HCl concentration, 90 °C, and 10 min of reaction time. The MCC produced under optimal conditions displayed improved crystallinity (77.2%) while retaining functional groups similar to those found in raw bamboo. Morphological analysis revealed an irregular rod-like shape with rough surfaces. This optimized hydrolysis process offers a viable approach for MCC production from raw bamboo and holds potential as a precursor for developing environmentally friendly biodegradable fiber materials. Full article

This study concerns the effects of the addition of crystalline nanocellulose (CNC) and ionizing radiation on the properties of cornstarch–poly(vinyl alcohol) (PVA) films. Moreover, ESR spectroscopy and gas chromatography were used for a comparison of the reactivity of CNC and two micro-sized celluloses (microfibrinal (MFC) and microcrystalline (MCC)) under the influence of irradiation. This showed that the highest reactivity of CNC was related to the lowest sizes of the particles (observed by SEM). A series of starch/PVA/CNC films characterized by a starch/PVA ratio equal to 40:60 and a CNC addition in a range from 0.5 wt% to 10.0 wt% with 30 wt% of glycerol were prepared by solution casting. The films were irradiated in a gamma chamber (in a vacuum) or in an e-beam (in the air) using a dose of 25 kGy. The mechanical properties, contact angle to water, swelling and solubility in water, moisture absorption in a humid atmosphere, and the gel content of the films were determined. The functional properties of the films strongly depended on the addition of CNC. The films formed with 1.0 wt% of CNC had the best mechanical properties and the lowest surface and bulk hydrophilicity, which could be improved further after irradiation. The results can be related to the increased homogeneity and modified distribution of the nanoparticles in the films after irradiation (as shown by SEM). Degradation is a predominant process that occurs due to irradiation; however, the crosslinking processes also have some role. The protective effect of CNC against degradation was discovered by diffuse reflectance spectroscopy. Full article

Air filters are crucial components of building ventilation systems. Compared to conventional air filter media like glass fibers and melt-blown fibers, electrospinning membranes are more efficient for capturing various pollutants due to the smaller pores present on the structure. In this paper, activated carbon filters were prepared with eco-friendly polylactic acid (PLA) and microcrystalline cellulose (MCC) using electrospinning to obtain a high-quality factor (QF) fibrous mat for aerosol particle matter (PM) filtration and volatile organic compounds (VOCs) adsorption. Several configurations of the final membranes were investigated and tested for fiber morphology and air filtration performance. Filtering efficiency and adsorption properties were evaluated in a real-scale room by measuring the particle penetration of the newly synthesized and commercial filters against neutralized aerosol particles (3% NaCl aqueous solution) and VOCs (methyl ethyl ketone). The calculated depolluting efficiencies were up to 98% in terms of PM and 55% for VOCs abatement, respectively. Our results indicate that the proposed hybrid membranes represent promising materials for highly efficient and sustainable air filters for home application systems. Full article

Cellulose is a versatile biopolymer increasingly applied in medicine and industry due to its biodegradability and biocompatibility, along with the renewability and large availability of source materials. However, finding simple, eco-friendly, and effective methods to modify cellulose to provide it with new functionalities remains a challenge. This work presents a new, inexpensive, and eco-friendly method to chemically modify microcrystalline cellulose (MCC) by the submerged cold plasma treatment of an aqueous suspension of MCC containing different oxidizing agents, such as hydrogen peroxide (H₂O₂), sodium hypochlorite (NaClO), or sodium periodate (NaIO₄). Fourier-transform Infrared (FTIR) and X-ray photoelectron spectroscopy (XPS) showed that plasma treatment intensified the oxidizing effect of H₂O₂, NaClO, and NaIO₄, with plasma-assisted NaClO treatment yielding the highest MCC oxidation level. XPS indicated that the plasma-assisted oxidations also resulted in different degrees of chemical degradation of MCC, a finding further supported by the thermogravimetric analysis (TGA) results. X-ray diffraction (XRD) data revealed a different effect of the oxidizing agents on the crystalline and amorphous regions in MCC. Scanning electron microscopy (SEM) images showed that the combined treatment with plasma and chemical oxidizing agents led to MCC fragmentation and varying degrees of defibrillation into nanofibers. Full article

The need for eco-friendly, cost-effective, and scalable methods to synthesize carbon quantum dots (CQDs) remains a critical goal in nanotechnology. In this work, nitrogen-doped carbon quantum dots (N-CQDs) were successfully synthesized using cellulose nanocrystals (CNCs) derived from microcrystalline cellulose (MCC) and urea through a rapid one-step microwave-assisted method. The use of renewable cellulose as a precursor aligns with sustainable practices, offering a pathway to transform agricultural waste into valuable nanomaterials. Characterized by TEM, XRD, Raman, XPS, and PL spectroscopy, the N-CQDs demonstrated outstanding optical properties, including strong excitation-dependent fluorescence with an emission maximum at 420 nm. The N-CQDs exhibited exceptional selectivity and sensitivity toward Fe³⁺, achieving a detection limit of 75 nM. Additionally, the pH-dependent fluorescence and stability in diverse conditions highlight the N-CQDs’ versatility in environmental monitoring. This study establishes a foundation for using agricultural waste to produce high-performance nanostructures for sensing applications, advancing green nanotechnology and environmental solutions. Full article

Bio-nanomaterials are gaining increasing attention due to their renewable and eco-friendly characteristics. Among these, nanocrystalline cellulose (NCC) stands out as one of the most advanced materials for applications in food, healthcare, composite production, and beyond. In this study, NCC was successfully extracted from cotton-based textile waste using a combination of chemical and mechanical methods. The cellulose fibers were first hydrolyzed using a dilute HCl solution, neutralized, and then dried, resulting in microcrystalline cellulose (MCC) with diameters ranging from 7 to 15 µm and lengths up to 300 µm (as observed via optical microscopy and scanning electron microscopy, SEM). To achieve nanoscale dimensions, NaOH/urea solution with mechanical treatment was applied, resulting in the successful extraction of NCC in the supernatant, particularly under room-temperature conditions. Dynamic light scattering (DLS) analysis confirmed the presence of nanostructures (average sizes ranging from 120 nm to 750 nm), and atomic force microscopy (AFM) analysis verified the nanoscale range (diameters between 2 and 4 nm and lengths from 200 nm to 1 µm). Fourier transform infrared (FTIR) spectroscopy revealed the conversion of cellulose I to cellulose II, confirming the successful transformation into NCC. For the first time, NCC was obtained from undyed cotton textile wastes using NaOH/urea treatment after HCl hydrolysis, eliminating the need for pre-treatment and intermediate steps. Full article

This study aims to enhance the mechanical properties of hot-waxed wood by incorporating microcrystalline cellulose (MCC), thereby addressing the issue of inadequate surface durability. We investigated the effects of varying mass fractions (0%, 5%, 10%, 15%) of MCC on multiple surface properties of hot-waxed wood modified with natural wax and maleic anhydride-ethyl acetate copolymer-grafted Fischer-Tropsch wax. These properties encompass adhesion, hardness, abrasion resistance, impact resistance, surface roughness, gloss, and hydrophobicity. To gain deeper insights into the reinforcing role of MCC, analytical techniques such as Fourier Transform Infrared Spectroscopy (FTIR), X-ray Diffraction (XRD), and Scanning Electron Microscopy (SEM) were employed to comprehensively characterize the chemical structure, crystalline structure, and surface morphology of the samples. The results reveal that, upon the addition of 5% MCC, the hot-waxed wood treated with modified Fischer-Tropsch wax demonstrates a 41% increase in surface adhesive strength, an improvement in hardness from 2H to 3H, a reduction in surface impact resistance from grade 5 to grade 2, and a 72% decrease in wear mass. Additionally, it exhibits enhanced surface hydrophobicity and thermal stability, while preserving its decorative appearance. These findings endorse the use of MCC in hot-waxed wood, offering significant potential in fields like wooden architecture, indoor wooden decorative panels, and furniture. Full article

This study reported a one-spot preparation of magnetic composite carbon (MCC@Fe) from microcrystalline cellulose (MC). The pure cellulose was impregnated in iron (III) chloride solution and carbonized at 650 °C. The MCC@Fe composite adsorbent underwent various characterization techniques. XRD identified nanostructured Fe₃O₄ particles with an average crystallite size of 34.3 nm embedded in the core subunits of the material. FESEM images indicated a rough and irregular surface, with some cavities along its surface, incorporating Fe₃O₄ nanoparticles, while EDS analysis confirmed the presence of elements like Fe, C, and O. Notably, combining thermal and chemical treatments produces a composite with more pores and a high specific surface area (500.0 m² g⁻¹) compared to MC (1.5 m²/g). VSM analysis confirmed the magnetic properties (0.76 emu/g), while the Hydrophobic Index (HI) showed that MCC@Fe was hydrophobic (HI 1.395). The adsorption studies consisted of kinetic, mass transfer, equilibrium, and thermodynamics studies. Kinetic study of the adsorption of paracetamol on MCC@Fe composite proved to be rapid, and the time necessary for covering 95% of the surface (t_0.95) was lower than 27 min following the fractal-like pseudo-first-order model (FPFO). Liu’s isotherm proved to be the most appropriate for understanding the adsorption equilibrium. Remarkably, the maximum sorption capacity (Q_max) of paracetamol was 34.78 mg g⁻¹ at 45 °C. The ΔH° value (+27.00 kJ/mol) and the negative ΔG° values were consistent with the physisorption mechanism and favorable process. Furthermore, the mass transfer mechanism showed that the transfer is governed by the intraparticle diffusion model, with surface diffusion being the rate-limiting step when considering the Biot number greater than 100. This research displayed a single-route production of inexpensive magnetic nano adsorbents capable of efficiently eliminating paracetamol from aqueous environments. Full article

Sliver carp is a nutritious and abundant species in China, but its low market value stems from its thin meat, small bones and strong odor. Processing it into surimi enhances its economic value, though surimi typically has low gel strength and is prone to deterioration. Recently, three-dimensional (3D) printing has gained attention as an innovative additive manufacturing technique for personalization and process simplification requiring high-performance materials. This study intended to develop an optimized surimi formula for 3D printing with dynamic high-pressure microfluidization (DHPM)-modified pea protein isolate (PPI) and microcrystalline cellulose (MCC). Firstly, the effect of DHPM on PPI properties was evaluated, followed by the optimization of the surimi gel formula (72.093% water content, 3.203% PPI, 1.728% MCC, 1% salt, 1% collagen peptide and 20.976% sliver carp paste) and 3D printing parameters (2000 mm/min at 25 °C with a 1.5 mm nozzle). Rheological comparisons between the optimized surimi, surimi with commercial antifreeze and surimi with only PPI or MCC indicated that the optimized formulation exhibited clearer 3D printing outlines and reduced stickiness due to a higher recovery and lower loss modulus. These results demonstrated that DHPM-treated PPI and MCC enhanced the 3D printability of silver carp surimi gel, providing a new idea for a surimi product and supporting its potential applications in food 3D printing. Full article

This study investigates the impact of micro- and nanocellulose coatings on the properties of wool fabrics using the solution blow spinning technique. The objective is to assess how varying cellulose sizes influence key fabric attributes, including physical properties, UV-shielding ability, air permeability and water vapour permeability, with a focus on their practical applications. Coating with microcrystalline cellulose (MCC) was found to increase the air permeability of fabric significantly, whereas coating with cellulose nanocrystals (CNCs) enhanced water vapour permeability and reduced pore size. The air permeability could relate to the breathability, and water vapour permeability could relate to the comfortability. Coated fabric with both sizes of cellulose could have different applications, like pollen filtration and printable cloth, and further functionality could be achieved by modifying the cellulose structure. This research establishes a platform for the effective application of cellulose coatings on wool fabric, offering promising advancements for textile performance and sustainability. Full article

This study focusses on imrpoving the mechanical performance of epoxy resin by reinforcing it with microcrystalline cellulose (MCC). Epoxy composites with varying MCC mass fractions (0.5%, 1%, 1.5%, and 2%) are prepared and characterised to assess the influence of MCC on strain-rate-dependent flexural properties, impact resistance, and nonlinear viscoelastic behaviour. Three-point bending tests at different strain rates reveal that MCC notably increases the flexural strength and leads to nonlinear mechanical behaviour. It is shown that stiffness, strength and elongation at break increase with rising MCC content. Charpy impact tests show improved energy absorption and toughness, while Dynamic Mechanical Analysis (DMA) demonstrates that the materials prepared exhibit increased storage modulus and improved damping across a frequency range. These results indicate that MCC serves as an effective bio-based reinforcement, significantly boosting the strength and toughness of epoxy composites. The findings contribute to the development of sustainable, high-performance materials for advanced engineering applications. Full article

Background: Precise continuous feeding of active pharmaceutical ingredients (APIs) and excipients is crucial in a continuous powder-to-tablet manufacturing setup, as any inconsistency can affect the final tablet quality. Method: This study investigated the impact of various materials on the performance of a continuous twin-screw loss-in-weight (LIW) feeder. The materials tested included spray-dried lactose, anhydrous lactose, granulated lactose, microcrystalline cellulose (MCC), an MCC–lactose preblend (50%:50% w/w ratio), and a co-processed excipient (lactose–lactitol at a 95%:5% w/w ratio). The feeding performance of these excipients was systematically assessed, focusing on powder densification and screw layering within the LIW feeder. Results: The results demonstrated densification for the spray-dried lactose and preblend. Densification was more pronounced during the initial feeding cycles for spray-dried lactose, but decreased gradually over time. In contrast, the densification remained relatively constant throughout the feeding process for the preblend. Notably, minor screw layering was observed for both spray-dried lactose and anhydrous lactose, with the extent of this issue reducing over time for the spray-dried lactose. Interestingly, granulated lactose grades did not show screw layering, making them preferable for blending with APIs prone to severe screw layering. The LIW feeder control system successfully managed powder densification and minor screw layering, maintaining the mass flow rate at the set point for all investigated materials. Conclusions: These findings inform the selection of optimal excipients, appropriate tooling for LIW feeders, and the enhancement of control strategies to shorten startup times. By addressing these factors, the precision and reliability of continuous feeding processes can be improved. Full article

Polyurethane foam (PUF) pads are widely used in semiconductor manufacturing, particularly for chemical mechanical polishing (CMP). This study prepares PUF composites with microcrystalline cellulose (MCC) and nanocrystalline cellulose (NCC) to improve CMP performance. MCC and NCC were characterized using scanning electron microscopy (SEM) and X-ray diffraction (XRD), showing average diameters of 129.7 ± 30.9 nm for MCC and 22.2 ± 6.7 nm for NCC, both with high crystallinity (ca. 89%). Prior to preparing composites, the study on the influence of the postbaked step on the PUF was monitored through Fourier-transform infrared spectroscopy (FTIR). After that, PUF was incorporated with MCC/NCC to afford two catalogs of polyurethane foam composites (i.e., PUFC-M and PUFC-N). These PUFCs were examined for their thermal and surface properties using a differential scanning calorimeter (DSC), thermogravimetric analysis (TGA), dynamic mechanical analyzer (DMA), and water contact angle (WCA) measurements. T_gs showed only slight changes but a notable increase in the 10% weight loss temperature (T_d10%) for PUFCs, rising from 277 °C for PUF to about 298 °C for PUFCs. The value of Tan δ dropped by up to 11%, indicating improved elasticity. Afterward, tensile and abrasion tests were conducted, and we acquired significant enhancements in the abrasion performance (e.g., from 1.04 mm/h for the PUF to 0.76 mm/h for a PUFC-N) of the PUFCs. Eventually, we prepared high-performance PUFCs and demonstrated their capability toward the practical CMP process. Full article

A lack of strategies for the utilization of harvest residues (HRs) has led to serious environmental problems due to an accumulation of these residues or their burning in the field. In this study, wheat and corn HRs were used as feedstock for the production of microcrystalline cellulose (MCC) by treatment with 2–8% sodium hydroxide, 10% hydrogen peroxide and further hydrolysis with 1–2 M hydrochloric acid. The changes in the FT-IR spectra and PXRD diffractograms after chemical treatment confirmed the removal of most of the lignin, hemicellulose and amorphous fraction of cellulose. A higher degree of crystallinity was observed for MCC obtained from corn HRs, which was attributed to a more efficient removal of lignin and hemicellulose by a higher sodium hydroxide concentration, which facilitates the dissolution of amorphous cellulose during acid hydrolysis. MCC obtained from HRs exhibited lower bulk density and poorer flow properties but similar or better tableting properties compared to commercial MCC (Ceolus^TM PH101). The lower ejection and detachment stress suggests that MCC isolated from HRs requires less lubricant compared to commercial MCC. This study showed that MCC isolated from wheat and corn HRs exhibits comparable tableting behaviour like commercial sample, further supporting this type of agricultural waste utilization. Full article

Materials for low-permittivity and electrical insulation applications need to be re-engineered to achieve sustainable development. To address this challenge, the proposed study focused on the dielectric and mechanical optimization of 3D-printed cellulose-based composites for electrical insulation applications. Two different fillers, microcrystalline cellulose (MCC) and nanocrystalline cellulose (NCC), were used to create biocomposites and bionanocomposites, respectively, blended into a polylactic acid (PLA) matrix. The effects of infill ratio, printing temperature, and filler content on dielectric and mechanical properties were measured using an incomplete L9 (3^3) factorial design. The findings showed that the infill ratio was the most significant factor influencing the properties tested, directly attributable to the increase in material availability for polarization and mechanical performance. The second most influential factor was the filler content, increasing the polarity of the tested composites and decreasing the toughness of the biocomposites and bionanocomposites. Finally, printing temperature had no significant effect. Results for the biocomposites at a 50% infill ratio, 200 °C printing temperature, and a weight content of MCC of 15% gave a 60% higher tensile-mode stiffness than neat PLA printed under the same conditions, while exhibiting lower dielectric properties than neat PLA printed with a 100% infill ratio. These results pave the way for new lightweight materials for electrical insulation. Full article