Acetate Composite Films Research Articles

Copper abietate/polyvinyl acetate composite film for enhanced humidity sensing in Chinese herbal medicine monitoring systems

Sensing materials derived from natural and biodegradable sources are increasingly being developed and applied to realize environmentally friendly technologies. In this paper, we present the synthesis, characterization, and application of a novel copper abietate/polyvinyl acetate (CuA/PVAc) composite film, specifically engineered to enhance the humidity-sensing capabilities of Chinese herbal medicine monitoring systems. The sensing material was synthesized by strategically melding copper abietate, a natural renewable material, with PVAc to exploit their combined synergistic properties for optimal humidity-sensing performance. Comprehensive characterization techniques, including inductively coupled plasma optical emission spectrometry (ICP-OES), field-emission scanning electron microscopy (FESEM), water contact angle measurements, and Fourier transform infrared (FT-IR) spectroscopy, were employed to confirm the formation of CuA/PVAc composites. These analyses confirmed the homogeneity and intended chemical composition of the composite films.The resultant CuA-1/PVAc-4 (0.4 μg/μL) composite film exhibited a good logarithmic relation (0.9988) with relative humidity (RH) over a wide range (11 %–97 %) and high sensitivity (24.55 Hz/%RH). Moreover, this study introduces a novel, eco-friendly approach by integrating the CuA/PVAc composite with a quartz crystal microbalance (QCM) sensor and a sophisticated wireless circuit that enables real-time, Wi-Fi-based humidity monitoring tailored for the preservation of Chinese herbal medicines. The implementation of this wireless humidity detection system represents a significant advancement in the application of environmentally friendly materials in sensor technology and offers a practical and scalable approach for precise environmental monitoring.

Structure and functional properties of aluminum hydroxide reinforced bamboo‐derived cellulose acetate composite film for biodegradable packaging

AbstractBiodegradable plastics are gaining popularity as environmentally friendly functional materials. This study focuses on the preparation of aluminum hydroxide (Al(OH)3) reinforced cellulose acetate composite films using a cost‐effective approach. The process involves synthesizing bamboo‐derived cellulose acetate (BDCA), dissolving it in tetrahydrofuran with glycerol as a plasticizer, and incorporating Al(OH)3 particles into the casting solution to reinforce the cellulose acetate film. Analyses on microstructure and characteristics of the films were conducted through various techniques, including scanning electron microscopy (SEM), Fourier transform infrared (FT‐IR) spectroscopy, x‐ray diffraction (XRD), water contact angle measurement, and tensile testing. The results indicate that the Al(OH)3 particles were well‐dispersed in the composite films, leading to a strong interaction with the cellulose acetate matrix. As a result, the prepared composite films exhibited significantly higher tensile strength compared to pure bamboo‐derived cellulose film. Additionally, they demonstrated improved anti‐ultraviolet properties and a lower water vapor transmission rate, despite being more hydrophilic. This method holds significant potential for commercial applications in producing high‐performance cellulose acetate‐based composite films.Highlights Bamboo‐derived cellulose acetate was synthesized through chemical processes. BDCA based composite film reinforced with Al(OH)3 was prepared by casting method. The Al(OH)3 significantly enhance the functional properties of the composite film. Composite films showed good performances for packaging according to the results.

In Situ Decoration of Bi2S3 Nanosheets on Zinc Oxide/Cellulose Acetate Composite Films for Photodegradation of Dyes under Visible Light Irradiation.

A novel Bi2S3-zinc oxide/cellulose acetate composite film was prepared through a blending-wet phase conversion and in situ precipitate method. The results revealed that the incorporation of Bi2S3 in the film increased the cavity density and uniformity, which provided additional space for the growth of active species and improved the interaction between dye pollutants and active sites. Zinc oxide acted as a mediator to facilitate the separation of electron-hole pairs effectively preventing their recombination, thus reducing the photo-corrosion of Bi2S3. As a result, the Bi2S3-ZnO/CA composite film exhibited favorable photocatalytic activity in the degradation of various dyes. Additionally, the composite film displayed effortless separation and recovery without the need for centrifugation or filtration, while maintaining its exceptional catalytic performance even after undergoing various processes.

Functional properties of nano-SiO2/pinewood-derived cellulose acetate composite film for packaging application

Petroleum-based plastics are widely used because of their practicable properties and low cost. However, people are equally concerned about the environmental damage generated by non-biodegradable petrochemical plastics. In this study, pinewood was employed as the raw material to prepare cellulose acetate and further synthesize the degradable composite films, which showed potential feasibilities to substitute the traditional petroleum-based plastics. In order to improve the barrier performance, hydrophobic performance, and mechanical properties of the film materials, nano-SiO2 was introduced as functional filler for experimental exploration. The tensile strength, light transmittance, water vapor transmittance, microstructure, and crystalline structure of the nano-SiO2/pinewood-derived cellulose acetate composite films were determined by mechanical analysis, optical analysis, SEM, XRD, FT-IR, and barrier characterization methods, respectively. The results exhibited that the prepared films with the inclusion of nano-SiO2 did not conduct reduction in transparency due to its good dispersion in the composite film. The barrier property, hydrophobic performance, and mechanical properties of cellulose acetate composite film were effectively improved due to the interaction between nano-SiO2 and cellulose acetate molecular chains by the hydrogen bonds formed between hydroxyl groups. It was confirmed that the nano-SiO2/pinewood-derived cellulose acetate composite films exhibit great application potential as an environmentally friendly and efficient material for packaging.

Properties and antimicrobial activity of wheat-straw nanocellulose-arabinoxylan acetate composite films incorporated with silver nanoparticles

In the current study, the novel eco-friendly and biodegradable nanocomposite films (NC-AXAc) were prepared from wheat-straw NC and AXAc with improved functional properties. NC derived from wheat-straw cellulose has a fibre-like structure with mean-particle size in the 340–520 nm range. AX derived AXAc was prepared with Degree of Substitution (DS) in the range of 1.85–1.89. Furthermore, to enhance antimicrobial properties, AgNPs were prepared via the reduction method using NaBH4 and added into the concentration of 4 × 10−4M into the emulsion forming composite films. The silver nanoparticles (AgNPs) incorporated in the composite exhibited an average size of 40–70 nm and a surface plasmon resonance (SPR) absorption peak at 395 nm. The high-resolution XPS spectrum of the Ag element showed that the two peaks at around 374.2 eV (Ag3d3/2) and 368.2 eV (Ag3d5/2) clearly revealed the metallic Ag existence in composite films. SEM analysis revealed the coarse and heterogeneous morphology of AgNPs incorporated films. The AgNPs incorporated composites exhibited good mechanical, thermal stability, and antimicrobial activity. The results suggested that AgNPs incorporated NC-AXAc composites could be used as a potential biodegradable antimicrobial nanocomposite in active food packaging systems for shelf-life extension of perishable commodities.

Durable and recyclable BiOBr/silk fibroin-cellulose acetate composite film for efficient photodegradation of dyes under visible light irradiation

Durable and recyclable BiOBr/silk fibroin-cellulose acetate composite film for efficient photodegradation of dyes under visible light irradiation

A polyaniline/polyvinyl acetate composite film electrode for highly sensitive electrochemical sensing of pH

The electrochemical performances of three types of polyaniline (PANI)-based films developed as pH-sensing electrodes were evaluated and compared. PANI emeraldine base (PANI-EB), PANI emeraldine salt (PANI-ES), and PANI-ES/polyvinyl acetate (PVAc) composite films were spin coated on fluorine-doped tin oxide (FTO) glass substrates to fabricate pH-sensing electrodes. The surface morphology, wetting properties, and electrochemical properties were characterized and compared. Unprotonated PANI-EB films had a regular structure with residual flakes, whereas protonated PANI-ES and PANI-ES/PVAc films exhibited globular and porous structures, respectively. All PANI-based films adhered well to the FTO substrate. Water contact angles indicated the hydrophobic characteristic of the PANI-EB films and the hydrophilicity of the PANI-ES films, which could affect their stability in buffered solutions of different pH. The PANI-ES/PVAc films exhibited improved stability because of the hydrophobic PVAc. The PANI-ES/PVAc electrodes exhibited a significantly higher pH sensitivity of 100 mV pH−1 than those of the single-component PANI-EB and PANI-ES electrodes (57 and 65 mV pH−1, respectively) in the pH range of 3.0–8.0, which could be attributed to the non-equilibrium protonation/deprotonation of nitrogen atoms in the PANI structure. Moreover, the PANI-ES/PVAc electrodes also exhibited good reproducibility and selectivity to H+ over certain other ions and molecules (e.g., glucose).

Structural, characterization, and linear/nonlinear optical behavior of polyaniline/cellulose acetate composite films

Structural, characterization, and linear/nonlinear optical behavior of polyaniline/cellulose acetate composite films

Performance Enhancement of Crystal Silicon Solar Cell by a CsPbBr3–Cs4PbBr6 Perovskite Quantum Dot @ZnO/Ethylene Vinyl Acetate Copolymer Downshifting Composite Film

Crystal silicon solar cells being the most successful photovoltaic devices have prevailed in the energy market for decades. To further improve the device performance, photon management is necessary. Herein, a CsPbBr3–Cs4PbBr6 perovskite quantum dot@ZnO/ethylene vinyl acetate copolymer downshifting composite film is coated on the silicon solar cell. This downshifting composite film helps to convert high‐energy (UV‐blue) photons to relatively low‐energy photons with a wavelength at about 500 nm, which possess higher sensitivity in silicon solar cells. The effects of tetra‐n‐heptylammonium bromide and Zn(C2H5)2 on composition, optical and luminescence properties of perovskite quantum dots are thoroughly investigated, and a clean quantum dot solution with strong luminescent intensity can be obtained. The perovskite quantum dot@ZnO/ethylene vinyl acetate composite film absolutely improves the efficiency of silicon solar cells by 1.18%. The value is much higher than pure ethylene vinyl acetate (0.42%) and composite film without ZnO (0.57%). Moreover, ZnO inclusion can inhibit Cs and Pb leakage and maintain the device working stability, which is helpful for their commercial application in the future. This study further reveals that the enhancement lies in carrier relaxation energy loss reduction. Herein, a low‐cost downshifting composite film with excellent environmental stability for silicon solar cells applications is proposed.

Catalysis of MnO2-cellulose acetate composite films in DBD plasma system and sulfamethoxazole degradation by the synergistic effect

Herein, dielectric barrier discharge (DBD) plasma and MnO2-cellulose acetate (MnO2/CA) composite films was coupled together to degrade sulfamethoxazole (SMX) in water. The MnO2/CA composite films were firstly prepared successfully though heating blending method in this study and then characterized by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), Raman spectra, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR) and thermogravimetric analysis (TG). Catalytic effect of the MnO2/CA films was investigated by comparing the removal percentages, the kinetic constants, the energy utilization efficiencies (G50) as well as the COD and TOC removal during the SMX degradation in the DBD plasma system with or without the MnO2/CA films addition under different reaction conditions. The optimal catalytic performance was obtained by adding the 3% MnO2/CA films into the DBD plasma system and the alkaline solution condition was favorable for the SMX degradation. After four times using, the MnO2/CA composite films still maintained the catalytic activity. Catalytic mechanism of the MnO2/CA films was speculated by analyzing the changes of solution pH and conductivity during the reaction, concentrations of the formed O3 and H2O2 in water and the generated active species (1O2 and ·OH) in both the DBD plasma system and the DBD-MnO2/CA films system. The quenching test was also carried out to figure out the important effect of the ·O2−, 1O2 and ·OH for the SMX degradation in the synergistic system. Finally, LC-MS was used to analyze the main intermediates generated during the SMX degradation and the possible degradation pathways were accordingly speculated. The research could provide a new direction for the development and application of the DBD plasma technology as well we the composite films catalyst.

The study of the particle size effect on the physical properties of TiO2/cellulose acetate composite films

Abstract The cast method was used to synthesize cellulose acetate (CA)/titanium oxide (TiO2) composites by varying TiO2 particle sizes at different weight ratios of 1, 1.5, 2, 2.5, and 3 wt%. The relationship between structural diversity and performance was explored. Microstructures and chemical composition of as-prepared composite films were revealed using field-emission scanning electron microscopy and Fourier-transform infrared spectroscopy. The tensile strength increased from 46.8 MPa for pure CA to 54.7 MPa for the CA-1% micro-TiO2 composite and 81.7 MPa for the CA-2% nano-TiO2 composite, according to the mechanical properties. The tensile strength decreased due to some degrees of agglomeration of filler particles above a critical content. UV-vis transmittance spectra showed that pure CA was almost transparent, CA-micro-TiO2 films were less transparent than pure CA, and CA-nano-TiO2 films could efficiently block the light. XRD diffraction for the synthesized membranes was performed. The patterns of micro-TiO2 and nano-TiO2 were shown as 2θ = 25° for the anatase phase and 2θ = 18.5 for the pure CA film, respectively. The hydrophilicity of films was also measured using the sessile drop technique. The contact angle value for the pure CA was 61.3°. As the amount of TiO2 added to the films increased, the contact angles of the CA-micro TiO2 and CA-nano TiO2 films reduced from 53.2° to 29° and from 51.5° to 27°, respectively. The produced films’ improved wettability indicated that these films could be employed as filters.

Solvodynamically Printed Silver Nanowire/Ethylene-co-vinyl Acetate Composite Films as Sensitive Piezoresistive Pressure Sensors

Pressure sensing is an important aspect of many processes and has a wide range of applications such as robotics and health monitoring. With the shift toward flexible and wearable technology, it is essential to develop high-performance flexible pressure sensors. In this study, we use solvodynamic printing to fabricate highly conductive piezoresistive composite films consisting of silver nanowires embedded in an ethylene-co-vinyl acetate matrix. The performance of the pressure sensor is tunable based on the composition and patterning of the film. The films can operate under a low input voltage (∼0.1 mV) with power consumption of <5 nW and show a low detection limit (12.9 ± 0.37 Pa), fast response time (11–22 ± 2.9 ms), and high sensitivity (67.3 ± 5.9 kPa–1) in the low-pressure regime, which is on par with commercially available pressure sensors. We further demonstrate the successful application of the film as a pulse-monitoring device.

Cellulose acetate composite films fabricated with zero‐valent iron nanoparticles and its use in the degradation of persistent organic pollutants

Cellulose acetate (CA), and CA blended with Nicotiana tabacum ash (ACA) membranes have synthesized and fabricated with zero‐valent Fe NPs (ZVI) and named as CA@Fe0 and ACA@Fe0. The as‐synthesized membranes were inspected for the removal and detoxification of toxic organic pollutants. Comparative studies of CA@Fe0 and ACA@Fe0 NPs were investigated for five model pollutants, such as 4‐nitrophenol (4NP), methyl orange (MO), Congo red (CR), methylene blue (MB), and bromocresol green (BCG). The kinetic model indicated that the apparent rate constant Kapp value of ACA@Fe0 was highest for all model pollutants compared to CA@Fe0 NPs. The Kapp value is derived from pseudo‐first‐order kinetics. The Kapp value of MO discoloration was 8.17 × 10−1 min−1 with ACA@Fe0 which is highest than CA@Fe0 (3.08 × 10−1 min−1). The turnover frequency (TOF) was highest for ACA@Fe0 for all the pollutants compared to CA@Fe0 and the highest TOF value was found for CR dye with ACA@Fe0 which is 0.523 h−1. Both the membranes also showed promising antibacterial activity against Salmonella typhi. Furthermore, CA, ACA membrane and CA@Fe0 and ACA@Fe0 NPs were characterized through FESEM, EDS, XRD, FTIR and TGA analysis.

Antibacterial nano cerium oxide/chitosan/cellulose acetate composite films as potential wound dressing

Novel chitosan and cellulose acetate polymer composites with nanosized cerium oxide were prepared as potential wound dressing materials. Chitosan and cellulose acetate are natural polymer derivatives with biocompatible properties. Both polymers can be dissolved in formic acid. The polymer composite was formed by solvent-casting method. The formed films were not soluble in water. In order to improve antibacterial, thermal, and mechanical properties of the composite material, films were loaded with nanosized cerium oxide. Films were characterized with thermogravimetric, scanning electron microscopy with energy-dispersive X-ray spectroscopy, mechanical, ultraviolet-visible light transmittance, water solubility, pH, moisture content, water vapor transmission rate, swelling, and antibacterial tests. The physical properties and antibacterial characteristics of the films are promising for further research as a potential wound covering material.

Carbon Nanotube/Cellulose Acetate Thermoelectric Papers

Free-standing single-walled carbon nanotube (SWCNT)/cellulose acetate composite films were fabricated by a simple bar-coating method. As a paste solvent, acetone, a low-boiling-point solvent, was u...

Preparation of all-inorganic perovskite quantum dots-polymer composite for white LEDs application

In recent years, all-inorganic lead halide perovskite CsPbX3 (X = Cl, Br, I) nanocrystals as kinds of new luminescent materials have attracted more and more attentions because of their size tunable emission wavelength, narrow emission peak, high luminous efficiency and good air stability. Herein we have synthesized all-inorganic halide perovskite nanocrystals by hot-injection method and anion exchange reaction, achieving the whole visible light region from 410 to 700 nm with narrow spectral in the range of 15–40 nm. Moreover, a white light emitting diode (WLED) was constructed by stacking CsPbBr3 QDs-ethyl acetate composite film and CaSrAlN3:Eu2+-poly (methyl methacrylate) composite film on the blue LED chip, displaying the ideal white light with the chromaticity coordination at (0.3379, 0.3432) and the color temperature of 5261 K. Because of the deep traps resulted from partial oxidation at the QDs' surface under large excitation light intensity, the WLED is not stable enough to work at a high operation current, but it can work steadily under a relatively lower operation current.

Conductivity and dielectric relaxation in various polyvinyl alcohol/ammonium salt composites

We studied electrical conductivity and dielectric relaxation in polyvinyl alcohol/ammonium chloride and polyvinyl alcohol/ammonium acetate composite films. Infrared absorbance showed the presence of H-bonding interaction between the salt and the polymer. X-ray diffraction showed the reduction of the grain size of ordered regions in the polymer matrix after adding salt. Thermo gravimetric analysis (TGA) showed water wt% content between 4.2 and 5.8%. Differential Scanning Calorimetry (DSC) showed the decrease of the glass transition due to retained water indicating its plasticizer effect. The ac conductivity studied in the frequency range from 10−1 Hz to 1 MHz and the temperature range from 10 to 150°C is described by the universal law of Jonsher characterizing the charge transport in disordered materials. With NH4Cl inclusion, the dc conductivity showed a higher value in the vicinity of 4% but with NH4CH3CO2 the dc conductivity decreases monotonically by increasing the salt amount. By using the dielectric permittivity and dielectric modulus we detected three relaxation processes which we attributed to electrode/sample polarization, alpha relaxation and conductivity relaxation respectively.

Structure and properties of hydroxyapatite/hydroxyethyl cellulose acetate composite films

The main aim of this research work was to develop a new inorganic–organic film. Hydroxyapaptite (HAp) particles that represent the inorganic phase was mixed well with hydroxyethyl cellulose acetate (HECA), which representing the organic phase and then the inorganic–organic films were fabricated by evaporating of the solvent. The structure as well as the properties of the formed films were characterized using different analytical tools such as field emission scanning electron microscopy (FEG-SEM), thermo-gravimetric analysis (TGA), Fourier transform infra-red (FT-IR) spectroscopy. The obtained results revealed that, the HAp nanoparticles was well dispersed and well immobilized throughout the formed films. This can be attributed to the role of the nano- and micropores in the HECA substrate. In addition, a strong interaction occurred between HAp and HECA matrix. The results showed also good thermal stability and miscibility as well.

Enhanced atomic oxygen erosion resistance and mechanical properties of graphene/cellulose acetate composite films

ABSTRACTThe application of graphene (Gr) to enhance atomic oxygen (AO) erosion resistance and mechanical properties was demonstrated in this study. Gr‐reinforced cellulose acetate (CA) composite films were obtained by flattening with a glass rod, and the AO erosion resistance was investigated in a plasma‐type, ground‐based AO effect simulation facility. Significant improvements in the mechanical properties and AO erosion resistance were achieved at relatively low Gr contents. A 59 ± 7% decrease in the mass loss and a 12 ± 3% increase in the tensile strength were achieved by the addition of only 1 wt % Gr. Moreover, the layered structure of the fractured surfaces and the excellent mechanical properties illustrated the homogeneous dispersion of Gr in the CA matrix and the strong interactions between Gr and CA. Furthermore, Gr flakes served as shields to defend the underside of CA from AO erosion because of the specific two‐dimensional structure and outstanding AO erosion resistance. Therefore, this research provides a new and effective strategy for improving the mechanical strength and AO erosion resistance of polymer materials. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40292.

Graphene for reducing bubble defects and enhancing mechanical properties of graphene/cellulose acetate composite films

In this study, we have demonstrated a strategy by which graphene was used to reduce the bubble defects and enhance the mechanical properties in graphene/cellulose acetate (Gr/CA) composite films. Mono- and multilayer graphene flakes were successfully prepared in the water–acetone mixtures by a jet cavitation method. Moreover, outstanding enhancement of mechanical properties of Gr/CA composite films were obtained at relatively low concentration of graphene flakes. Young’s modulus of these composite films increased linearly with the graphene flakes loading, due to the significantly high surface area of graphene and strong interactions between graphene flake and CA. Furthermore, three-dimensional channel formed by graphene flakes could increase the degassing speed and reduce the negative effects of bubbles. The Gr/CA composite has excellent mechanical properties and, more importantly, it is a natural and environmentally friendly polymer composite.