Cellulose Diacetate Research Articles

Enhanced air filtration and ammonia sensing with cellulose nanofibers-based triboelectric nanogenerators under harsh environments

Fire accidents often occur in environments characterized by severe air pollution, toxic gas emissions, and microbial growth, creating significant challenges for developing multifunctional portable healthcare devices. These devices must achieve high filtration efficiency, minimal pressure drop, and the capability to provide early warnings of toxic gas leaks. Triboelectric nanogenerators present a sustainable solution as self-powered energy converters for advanced healthcare applications. In this study, we grafted Ti3C2Tx/MoS2 nanohybrid materials, which form Schottky heterojunctions, onto cellulose diacetate using tetraethyl orthosilicate, followed by electrospinning to produce nanofibrous films. When paired with a negatively charged material, the resulting device achieved an optimal balance with a low-pressure drop (52 Pa) and high filtration efficiency (98.72 % for PM0.3). It also demonstrated exceptional stability under high-temperature and high-humidity conditions. Notably, the device maintained rapid sterilization within 15 min and consistent filtration performance even after multiple washes. Furthermore, the device exhibited precise detection of trace amounts of NH3 (0.1 ppm) and demonstrated a rapid response, achieving an 86 % response rate within 2 s for 100 ppm NH3, providing an early warning 28 s faster than commercial NH₃ monitors. This study introduces a novel approach to the development of multifunctional, self-powered, wearable medical devices that offer high-efficiency air filtration and sterilization, breath monitoring, and rapid toxic gas leakage detection in harsh environments.

Highly Porous Particles of Cellulose Derivatives for Advanced Applications.

A chemical modification of cellulose diacetate by phthalate and nitrate was performed to increase solubility in organic solvents and change the electrical properties. The role of substituents on the conductivity, permittivity, and polarizability of cellulose films is revealed. It has been shown that highly porous micro particles can be obtained from cellulose derivatives by a simple and technological freeze-drying method. The resulting micro sized aerogels have a predominantly spherical morphology and amorphous structure. Suspensions of porous particles of nitro- and phthalylated cellulose derivatives in silicone oil have an increased dielectric permittivity compared to cellulose diacetate particles. Produced particles are novel promising material with tunable electrical properties for advanced applications in composites, including for electrorheological fluids.

Electrokinetic Properties of Cellulose Diacetate—Influence of Morphology and Crystallinity on the Zeta Potential

AbstractThe study presents the electrokinetic properties of the zeta potential and the isoelectric point for cellulose diacetate (CA) in the forms of powder, nonporous film, and porous film. Surface zeta potential (ζ) and isoelectric point (IEP) are important properties that reflect the material's behavior in contact with liquids, as a consequence of the surface charge density and the morphology of the material. Nonporous films are prepared by casting CA solution on glass and Teflon dishes, while the porous film is prepared by the solution blow spinning (SBS) technique. The ζ potential is determined using the streaming potential method in the pH range from 2.5 to 9.5. The influence of the material's crystallinity (CI) and surface roughness (Sa) on the zeta potential is studied. The form of the material (powder, porous film, or nonporous film) influences the electrokinetic properties, which may have consequences on their behavior in contact with liquid (e.g., for processes such as oxidation, surface modification, grafting, or aging during use).

Development of carbon dots‐immobilized fluorescent polylactic acid hydrogel ink toward security authentication

AbstractA self‐healable hydrogel for advanced authentication applications was successfully developed. In the presence of an aqueous solution of ammonium hydroxide as a cheap passivating agent, the hydrothermal carbonization of cellulose diacetate extracted from rice straw yielded nitrogen‐doped carbon dots (NdCD) in a straightforward and ecologically beneficial manner. NdCD achieved a maximum quantum yield of 25.11%. Self‐healing biocomposite inks with different emission properties were created by using different concentrations of NdCD nanoparticles (NPs). In order to create a transparent layer of NdCD@PLA hydrogel, stamps were used to press homogenous films onto paper surfaces. Polylactic acid (PLA) hydrogel was embedded with NPs of NdCD. Self‐healing security hydrogel inks are highly durable. The NdCD@PLA hydrogel is efficiently self‐healable at room temperature. The current NdCD@PLA hydrogel can attach to different surfaces, such as glasses, plastics, and papers. The self‐healable nanobiocomposite was photostable when exposed to UV light. Under UV light, NdCD‐containing nanobiocomposite inks have a bluish color, as proved by both colorimetric parameters and fluorescence spectra. The morphological properties of NdCD were studied by transmission electron microscopy to suggest a particle diameter of 10–15 nm. The morphology of the fluorescent prints was analyzed using a number of different analytical methods. The hydrogel rheology and the mechanical performance of printed papers were tested. The printed films showed excitation and fluorescence bands at 401 and 488 nm, respectively. The present smart ink shows significant promise as a potential industrial production technique to simply produce anti‐counterfeiting prints.Highlights Rice straws were used to prepare nitrogen‐doped carbon dots with a quantum yield of 25.11%. Self‐healable polylactic acid hydrogel was immobilized with N‐doped carbon dots (10–15 nm). Transparent printed films shifted in color to blue (488 nm) when excited at 401 nm. Ultraviolet‐stimulated photochromic authentication prints were prepared. Printed paper demonstrated non‐cytotoxicity, high photostability, and durability.

Superhydrophilic and underwater superoleophobic polylactide/cellulose diacetate composite nanofibrous membranes for effective oil-in-water emulsions separation

Electrospun polylactide (PLA) fibrous membranes, characterized by good biodegradability and high porosity, demonstrate significant potential for oily wastewater treatment. However, the inherent hydrophobicity of PLA poses a significant challenge in separating oil-in-water emulsions. Herein, a facile and effective strategy was proposed to fabricate a PLA based nanofibrous membrane for oil-in-water emulsions separation. By combining the electrospinning and nonsolvent-induced phase separation technologies, hydrophilic cellulose diacetate (CDA) networks were in-situ constructed throughout the entire body of PLA fibrous membrane, resulting in a unique hierarchical porous structure. As a result, the obtained PLA/CDA composite nanofibrous membrane exhibited intriguing superhydrophilicity and underwater superoleophobicity, as well as gratifying separation performances for various oil-in-water emulsions solely under the driving force of gravity. Furthermore, the PLA/CDA composite nanofibrous membrane could be easily reused and will not bring out significant environmental concerns after extended use and disposal. We anticipate that this work could pave a way for the development of environmentally friendly membranes for oily wastewater treatment.

Cellulose Diacetate Aerogels with Low Drying Shrinkage, High-Efficient Thermal Insulation, and Superior Mechanical Strength.

The inherent characteristics of cellulose-derived aerogels, such as their natural abundance and environmental friendliness, make them highly interesting. However, its significant shrinkage before and after the supercritical drying procedure and low mechanical strength limit its potential application. Here, we propose a strategy to prepare cellulose diacetate aerogels (CDAAs) with low drying shrinkage, exceptional thermal insulation, and superior mechanical strength. The low drying shrinkage (radial drying shrinkage of 1.4%) of CDAAs is attributed to their relative strong networking skeletons, which are greatly formed by tert-butanol solvent exchange in exerting the interaction of reducing the surface tension force. In this case, CDAAs are eventually endowed with the low bulk density of 0.069 g cm-3 as well. Additionally, as-prepared CDAAs possess an abundant three-dimensional networking structure whose pore size is concentrated in the diameter range of ~50 nm, and the result above is beneficial for improving the thermal insulation performance (thermal conductivity of 0.021 W m-1 K-1 at ambient environmental and pressure conditions). On the other hand, the optimal compressive stresses of CDAAs at 3% and 5% strain are 0.22 and 0.27 MPa respectively, indicating a mechanically well robustness. The above evidence demonstrates indeed the exceptional thermal insulation and superior compressive properties of CDAAs. This work may provide a new solution for developing a kind of high-performance cellulose-derived aerogel in the future.

Understanding the formation of insoluble gel particles during cellulose diacetate production

Understanding the formation of insoluble gel particles during cellulose diacetate production

Mechanically robust ultrathin nanofibrous films by using microfluidic-based continuous printing.

Ultrathin nanofibrous films with unique properties, such as controlled thickness, structures, and excellent mechanical robustness, play a vital role in flexible wearable devices, electronic skin, and rechargeable batteries. However, nanofibrous films are always facing limitations in their mechanical properties, even though they are strong when used as textiles, mainly owing to their structural shortcomings by using conventional fabrication methods. Herein, we present the fabrication of free-standing ultrathin nanofibrous films with good mechanical properties by using a microfluidic-based continuous printing strategy. Owing to the precisely controllable microfluidic flow in the micrometre-scale, the resulting aramid nanofibre (ANF) films can reach thicknesses as low as 140 ± 25 nm. Specifically, the tensile strength of such ultrathin ANF films is recorded at an impressive value of 667 ± 40 MPa, representing a 120% improvement compared to the films prepared by using casting method. Such excellent mechanical robustness comes from the double-sided protonation, which shows a symmetrically dense structure compared to the asymmetric structure of cast films. Furthermore, we demonstrate the continuous fabrication of thin regenerated cellulose nanofiber (RCNF) and cellulose diacetate (CDA) films using the microfluidic-based printing strategy. Both microfluidic-based films show significant enhancements in strength, with a 42% increase for RCNF and a 94% increase for CDA compared to their cast films. We envision that this microfluidic-based continuous printing strategy provides a promising pathway for the development of advanced ultrathin nanofibrous films towards practical applications.

The Effect of NaOH Concentration and Acetylation Time on Synthesis of Kepok Banana Peel Cellulose Acetate

<p>The high production of kepok banana is generating a significant amount of peel waste, contributing to environmental pollution. To address this issue, an innovative solution is the conversion of kepok banana peel into cellulose acetate as raw material for membrane production. Therefore, this research aimed to manufacture kepok banana peel cellulose acetate using varying concentrations of 1%, 1.5%, and 2% NaOH solvent, with acetylation times of 2 hours and 2.5 hours, respectively. The optimal results were achieved using 1% NaOH with kepok banana peel cellulose content of 56.07%. Furthermore, the best acetylation time occurred at a duration of 2.5 hours, producing a cellulose acetate content of 38.23% and a 2.3% degree of substitution (DS). These results suggested that the optimal combination for producing membrane from kepok banana peel is 1% concentration with an acetylation time of 2.5 hours, classifying it as cellulose diacetate.</p>

Distinct microbial communities degrade cellulose diacetate bioplastics in the coastal ocean.

Cellulose diacetate (CDA) is a promising alternative to conventional plastics due to its versatility in manufacturing and low environmental persistence. Previously, our group demonstrated that CDA is susceptible to biodegradation in the ocean on timescales of months. In this study, we report the composition of microorganisms driving CDA degradation in the coastal ocean. We found that the coastal ocean harbors distinct bacterial taxa implicated in CDA degradation and these taxa have not been previously identified in prior CDA degradation studies, indicating an unexplored diversity of CDA-degrading bacteria in the ocean. Moreover, the shape of the plastic article (e.g., a fabric, film, or foam) and plasticizer in the plastic matrix selected for different microbial communities. Our findings pave the way for future studies to identify the specific species and enzymes that drive CDA degradation in the marine environment, ultimately yielding a more predictive understanding of CDA biodegradation across space and time.

Properties of Polymer Films Based on Cellulose Diacetate with Intercalated Zn{(NH2)2Co}2Br2

The work is devoted to the fabrication and study of electret material based on cellulose diacetate polymer film with an intercalated active component, polar macromolecules Zn{(NH2)2CO}2Br2. The introduction of macromolecules into the film was carried out during its formation from solutions of various concentrations of cellulose diacetate and Zn{(NH2)2CO}2Br2 in tetrahydrofuran with ethyl alcohol under the action of a constant electric field of 2–4 kV cm–1. The temperature curves of the dielectric constant ε, the dielectric loss tangent tan δ, as well as the thermally stimulated depolarization currents j of the resulting films were determined. It was established that modification leads to the appearance of additional maxima in the ε(T), tan δ(T), and j(T) curves caused by the active component embedded in the film. Modification of a cellulose diacetate film causes an increase in the value of j and the surface charge density found from the j(T) curve by more than two orders of magnitude. The results obtained indicate the possibility of application of the method under consideration to fabricate electret films.

Computational and Experimental Study of the Mechanical Properties of Porous Particles Based on Cellulose Diacetate

Computational and Experimental Study of the Mechanical Properties of Porous Particles Based on Cellulose Diacetate

Micro-porous cellulose diacetate films obtained from coffee parchment: Physicochemical properties, biodegradability, and their performance as dye adsorbent

Micro-porous cellulose diacetate films obtained from coffee parchment: Physicochemical properties, biodegradability, and their performance as dye adsorbent

Novel method for the prediction of distribution and elution characteristic of several drugs in cellulose diacetate-water system: Interaction between mixed solvent and cellulose diacetate

Drug-loaded cellulose diacetate (CDA) membranes were prepared by dissolving cellulose diacetate in a mixed solvent of acetone and ethanol, adding the drug to it, pouring it on a glass plate and evaporating the solvent. In this study, it was prepared CDA membranes varying composition of the mixed solvent (the mass ratio of acetone (ACE) to ethanol (EtOH)) and investigated their microstructure and performance.The release properties of drugs in drug-loaded CDA membranes were examined in correlation with the composition of the mixed solvent and a method to be able to predict the release properties of drugs was proposed. Penicillin G potassium, streptomycin sulfate and ampicillin were used as drugs. The microstructure of the membranes was determined using SEM analysis and the release properties of drugs were measured using spectrofluorophotometer. It was shown that the composition of the mixed solvent can have a significant effect on the overall performance of CDA membrane. The intrinsic viscosity measurements and solubility parameter analysis proved that the intrinsic viscosity of CDA in polymer solutions with mixed solvents and the solubility parameter difference (Δδ) between mixed solvents and CDA were relative with the release properties of drugs. The release rates of drugs from the membrane related to △δ directly and the intrinsic viscosity inversely. Therefore, the release rates of drugs from CDA membrane can be controlled by changing the composition of the solvent used for the preparation of the polymer membrane.

Does pervasive interconnected network of cellulose nanocrystals in nanocomposite membranes address simultaneous mechanical strength/water permeability/salt rejection improvement?

In this research work, we investigated the effect of two cellulose nanocrystal (CNC)-related parameters, namely aspect ratio and loading content on the mechanical and desalination performance of a cellulose diacetate (CDA) model membrane system. Dispersion of high aspect ratio (HAR) CNCs in the CDA resulted in different types of nanoassembly, represented by evaluating the mechanical efficacy coefficient (CFE), viscoelastic responses and separation performance of the nanocomposite membranes. Accordingly, 0.15 and 0.25 wt% showed random isolated dispersion and tight polymer-nanorod network, while 0.50 and 0.75 wt% conformed to nanorods' pervasive interconnected network (PIN) through side-by-side aggregation and intensive bundle alignment, respectively. Specifically, the nanocomposite membrane containing 0.50 wt% HAR-CNCs simultaneously demonstrated improved mechanical strength along with mitigated water permeability/salt rejection tradeoff for brackish water desalination. This concurrent boosting was attributed to the effective mechanical reinforcement mechanism induced by the percolating network along with its partial aggregation-caused bi-continuous and electrostatically-controlled nano-pathways, orchestrating the separation tradeoff. It confirmed our hypothesis that a nanocomposite membrane with metamaterial characteristic could be obtained via manipulating the dispersion state of CNC rods in the CDA, triggering coincided optimization of mechanical strength and desalination performance.

Biodegradability of Cellulose Diacetate in Aqueous Environments

Cellulose acetate with a degree of substitution (DS) of 2.5, commonly referred to as cellulose diacetate, has been discussed as an important source of microplastic in the environment, especially since it is used to produce cigarette filters. According to EU Single-Use Plastics Directive tobacco products are one of the ten most found SUP products in beach litter by number. However, at present only very few biodegradation studies with natural microbial communities in aqueous media have been reported. In the present study aqueous aerobic biodegradation simulation tests were performed on commercial materials according to international standards (ASTM D6691, ISO 14851 and ISO 19679) to address this bias. Cellulose diacetate proved to be biodegradable or showed strong indication to be non-persistent in freshwater (> 90% relative biodegradation after 100 days at 21 °C), seawater (> 90% after 142 days at 30 °C) and seawater/sediment interface (> 70% after 360 days at 25 °C) under defined laboratory conditions. In freshwater, biodegradation of cellulose diacetate was characterized by a prolonged lag phase (75 days), followed by > 90% relative biodegradation in a short time frame (25 days). This indicates that an abiotic degradation or hydrolysis to reduce the DS is not a pre-requisite to initiate the biodegradation of cellulose diacetate. In addition, it was found that the lag phase can be significantly shortened (from 75 to 5 days) by using pre-adapted microorganisms. In contrast to what could have been expected from literature our present study demonstrates that microorganisms can adapt to a DS as high as 2.5 and metabolize the material. This underlines the importance of studies with natural communities of microorganisms to get a more realistic idea of the persistence of a polymer material.

Environmentally benign plant-based polymeric organogel for wastewater treatment

Designing thermally and chemically stable adsorbents with higher efficiency than traditional adsorbents for wastewater treatment from natural resources has been getting the attention of the scientific community recently. In our search for better toxic dye adsorbents, in the present investigation, we have designed polymeric organogel by interacting polyvinyl alcohol (PVA) with cellulose diacetate (CA) using phthalic anhydride (PA) as the cross-linker. Here, cellulose diacetate (CA) was synthesized from cellulose phytochemically extracted from Dalbergia sissoo bark biomass. The cross-linking of CA with PA improved the polymeric organogel's stability and its dye adsorption capability over the pristine polymeric (PVA) organogel (12 %). The structure, morphology, and thermal stability of the organogel were evaluated using various state-of-the-art analytical techniques. The polymeric organogel offers 78% (223.46 mg/g) adsorption capability for the crystal violet (cationic), 69% (181.3 mg/g) for the congo red (anionic) against the 52%, and 48% of pristine PVA-based hydrogel. Based on the findings, produced organogel might be used as an environmentally safe, thermally stable, and more effective adsorbent for removing synthetic dyes from wastewater.

Study on the Properties of Cellulose Acetate Composite Synergistically Toughened by Glycerol Triacetate and Modified Nano Titania

Glyceryl triacetate (GT) and nano titanium dioxide (TiO2) filler modified by titanate coupling agent were used to toughen cellulose diacetate to prepare CA/GT/nano TiO2@NZD-201 composites. The effects of glyceryl triacetate and modified titanium dioxide filler on the mechanical properties and rheological properties of cellulose acetate were studied. The rheological properties showed that glyceryl triacetate and modified nano TiO2 significantly increased the plasticity of the composite, reduced the complex viscosity, reduced the rigidity, and increased the viscoelastic ratio. The impact resistance of the composite was improved by 101% due to the addition of modified nano titanium dioxide.

Valorisation of eyewear bioplastics through HTC and anaerobic digestion: Preliminary results

Bioplastics are increasingly replacing traditional plastics in many sectors, but the legislative and operative frameworks for their disposal remain unclear: they should be collected and treated together with the organic fraction of municipal solid waste (OFMSW), but often do not biodegrade satisfactorily in the plants that treat OFMSW. This work focuses on a type of cellulose diacetate employed in the eyewear industry to analyse hydrothermal carbonization (HTC) as a pre-treatment before anaerobic digestion (AD). The results show that HTC can hydrolyse this bioplastic even at moderate temperatures, reaching an almost total dissolution in the liquid phase at 210 °C and, at higher temperatures, producing hydrochar. When the HTC slurry obtained at 210 °C is fed to mesophilic or thermophilic AD, both the amount and the production rate of biogas are enhanced compared to the raw bioplastic. In particular, in thermophilic conditions, the amount of produced biogas undergoes at least a threefold increase compared to the untreated cellulose diacetate. Thus, this work confirms that a prior HTC step may be a suitable approach to enhance the disposal and energy recovery of bioplastics through AD.

Melt Processible Biodegradable Blends of Polyethylene Glycol Plasticized Cellulose Diacetate with Polylactic Acid and Polybutylene Adipate-Co-Terephthalate

Enhancing the melt processability of cellulose is key to broadening its applications. This is done via derivatization of cellulose, and subsequent plasticization and/or blending with other biopolymers, such as polylactic acid (PLA) and polybutylene adipate terephthalate (PBAT). However, derivatization of cellulose tends to reduce its biodegradability. Moreover, traditional plasticizers are non-biodegradable. In this study, we report the influence of polyethylene glycol (PEG) plasticizer on the melt processibility and biodegradability of cellulose diacetate (CD) and its blends with PLA and PBAT. CD was first plasticized with PEG (PEG-200) at 35 wt%, and then blended with PLA and PBAT using a twin-screw extruder. Blends of the PEG plasticized CD with PLA at 40 wt% and with PBAT at 60 wt% were studied in detail. Dynamic mechanical analysis (DMA) showed that PEG reduced the glass transition of the CD from ca. 220 °C to less than 100 °C, indicating effective plasticization. Scanning electron microscopy revealed that the CD/PEG-PBAT blend had a smoother morphology implying some miscibility. The CD/PEG-PBAT blend at 60 wt% PBAT had an elongation-to-break of 734%, whereas the CD/PEG-PLA blend had a tensile strength of 20.6 MPa, comparable to that of the PEG plasticized CD. After a 108-day incubation period under simulated aerobic composting, the CD/PEG-PBAT blend at 60 wt% PBAT exhibited a biodegradation of 41%, whereas that of the CD/PEG-PLA at 40 wt% PLA was 107%. This study showed that melt processible, biodegradable CD blends can be synthesized through plasticization with PEG and blending with PBAT or PLA.