Preparation Of Composite Materials Research Articles

Carbon-decorated diatomite stabilized lauric acid-stearic acid as composite phase change materials for photo-to-thermal conversion and storage

Diatomite is a promising supporting matrix in the preparation of composite phase change material for latent thermal energy storage. Raw diatomite has the advantages of porous space but with a shortage of thermal conductivity than carbon materials. In this work, the carbon-decorated diatomite (DC) matrix was synthesized by a novel template-carbonization method at different calcination temperatures of 600 °C, 800 °C, and 1000 °C. Then, the matrix was used to stabilize binary lauric-stearic acid of LA-SA for the preparation of diatomite-based composite phase change material which is used to explore the application of composite in photo-to-thermal conversion/storage. Results show that the carbon-decorated process on diatomite causes an increment of specific surface area and pore space. Thus, more phase change material being loaded in the matrix leads to a larger heat storage capacity of the composite. The designed composite with a matrix carbonization temperature of 1000 °C, LA-SA/DC-1000, has a loadage of 49.92 %, melting temperature of 31.48 °C, and latent heat of 70.07 J g-1 which is improved by 23 %. Compared with the raw diatomite-based composite, the enhancements of thermal conductivity were 90 % for that of LA-SA/DC-1000. Moreover, the corresponding composite exhibits better photo-to-thermal conversion performance and transient temperature response.

3D composite printing: study of carbon fiber incorporation to different construction thermoplastic matrices in regard to dilatation characteristics

Purpose The purpose of this paper is to clarify the relationship between the use of different polymer matrices for the preparation of composite materials, namely, polyethylene terephthalate-glycol (PET-G) and polyamide (PA), using Composite Fiber Co-Extrusion technology with the application of two types of carbon fibers, short and continuous. The aim of the study is also to extend the knowledge of the production of composite materials with a defined structure from the point of view of their influence on the microstructure and their physical-mechanical properties. Design/methodology/approach As part of the experiment, four types of samples were prepared, namely, two types of samples with PA polymer matrix and two types with PET-G polymer matrix. All types contained short carbon fibers and always one set from each polymer matrix in addition to continuous carbon fibers. All types were prepared using the same 3D printing parameters to avoid any further influence. The samples were then tested for microstructure using microCT, mechanical properties using a tensile test and dilatation characteristics from the point of view of aerospace applications. Finally, the raw materials themselves were tested. Findings The paper provides insight into the influence of polymer matrix types on the physico-mechanical properties of 3D printed composites. The analysis confirmed that the physico-mechanical results varied with respect to the interface between the polymer matrix and the carbon fiber. The implications of the conclusions can be extended to the development of products in the aerospace and automotive sectors. Originality/value This study provides information for composite applications in the aerospace industry, focusing on evaluating dilatation characteristics within very low temperatures (−60 °C) when using carbon fibers (continuous carbon fibers, short carbon fibers and a combination of both) in two types of thermoplastic matrices. This perspective on materials characterisation for aerospace applications is a very important and unpublished approach within the 3D printing of composites. These characteristics are important parameters in the design of prototypes and functional samples with regard to the resulting behaviour in real conditions.

Interfacial modification of titanium/steel composites and its effect on the growth pattern of Fe-Ti compounds

The formation of brittle compounds at the titanium/steel interface, which weakens bonding strength, is a significant challenge that must be addressed to broaden its use in sectors like petrochemical engineering and pressure vessels. Previous research has improved bonding strength by adjusting the diffusion coefficient on the titanium side. However, it also revealed problems with the rapid increase in TiC layer thickness and the precipitation of Fe-Ti compounds at temperatures above 950°C. This study introduces a new method based on the coordinated control of titanium/steel diffusion coefficients to create a TiC barrier effect at the interface, thus preventing the formation of brittle Fe-Ti compounds. The research methodically examines the effects of coordinated diffusion coefficient control between 850°C and 1000°C on the composite interface structure and further enhances bonding strength. The findings show that the coordinated control of titanium/steel diffusion coefficients effectively stabilizes the interface structure as α-Ti, TiC, and γ-Fe, inhibiting the formation of Fe-Ti compounds. As the rolling temperature rises from 850°C to 1000°C, the bonding strength increases from 190 MPa to 340 MPa. Near the composite interface on the steel side, a (101) oriented layer forms, and the diffusion distance of carbon significantly decreases to 10μm. The composite interface layer transitions from a mixed layer of TiC and Fe-Ti with a thickness of approximately 470 nm to a uniform and continuous TiC layer about 200 nm thick. This breakthrough overcomes the limitations of rolling temperature and excessive thickening of interface brittle compounds, expanding the process window for titanium/steel composite material preparation and establishing a link between diffusion coefficients, interface structure, and mechanical properties.

Preparation and Hydration Properties of Sodium Silicate-Activated Municipal Solid Waste Incineration Bottom Ash Composite Ground-Granulated Blast Furnace Slag Cementitious Materials.

The production of municipal solid waste incineration bottom ash (MSWIBA) is substantial and has the potential to replace cement, despite challenges such as complex composition, uneven particle size distribution, and low reactivity. This paper employs sodium silicate activation of MSWIBA composite Ground-granulated Blast Furnace slag (GGBS) to improve the reactivity in preparing composite cementitious materials. It explores the hydration performance of the composite cementitious materials using isothermal calorimetric analysis, Fourier-transform infrared (FTIR) spectroscopy, XRD physical diffraction analysis, and SEM tests. SEM tests were used to explore the hydration properties of the composite gelling. The results show that with an increase in MSWIBA doping, the porosity between the materials increased, the degree of hydration decreased, and the compressive strength decreased. When the sodium silicate concentration increased from 25% to 35%, excessive alkaline material occurred, impacting the alkaline effect. This inhibited particle hydration, leading to a decrease in the degree of hydration and, consequently, the compressive strength. The exothermic process of hydration can be divided into five main stages; quartz and calcite did not fully participate in the hydration reaction, while aluminum did. The vibrational peaks of Si-O-Ti (T = Si and Al) were present in the material. The vibrational peaks of XRD, FTIR, and SEM all indicate the presence of alumosilicate network structures in the hydration products, mainly N-A-S-H and C-A-S-H gels.

MXene-modified lemon peel-based composite phase change material with excellent photo-thermal conversion efficiency, thermal storage capacity and thermal conductivity for thermal management of electronic components

The preparation of multifunctional composite phase change materials using green technology to achieve an efficient energy storage and conversion remains an issue of concern. In this paper, a lemon peel-based porous carbon (LPC) composite phase change material (CPCM) was prepared by using polyethylene glycol (PEG) 6000 as a phase change medium and MXene nanosheet-modified carbonized lemon peel as a support carrier. MXene nanosheets were bonded to a lemon peel-based porous carbon skeleton to construct an excellent continuous three-dimensional thermally conductive grid system. What makes it noteworthy is that the presence of MXene nanosheets substantially improves the thermal conductivity (0.66 W/mK) and photo-thermal conversion efficiency (θ = 96.4 %) of MXene-modified lemon peel-based porous carbon/polyethylene glycol composite phase change materials (PEG/LPC@M). It is noteworthy that PEG/LPC@M has remarkable thermal stability and still has high enthalpy after 100 cycles, which further proves the recyclability of PEG/LPC@M and PEG/LPC@M embodies great potential in the field of thermal management of electronic components. In conclusion, a novel multifunctional CPCM was prepared by a simple and green process method in this study, which provides a new idea for waste recycling and reuse, and also has a wide range of applications in thermal management of electronic devices.

Green-process preparation and characterizations of optically transparent, thermally stable and mechanically superior regenerated silk-hyaluronate composite films

High-performance regenerated silk-hyaluronate composite films prepared by an environment-friendly process were highly desirable for medical dressing base material. In this study, sericin was removed from silk by steam treatment without using any chemical reagent, and a low concentration solution of Na2CO3 was used as a green process to dissolve silk fibers. Then the obtained silk fibroin was physically blended with sodium hyaluronate to generate optically transparent, thermally stable and mechanically superior regenerated silk-hyaluronate films. The results of structural characterizations and property tests showed that the insoluble silk short fibers prepared by the dissolution of Na2CO3 were dominated by a β-sheet crystalline structure while the soluble silk fibroins by an amorphous structure. Moreover, both insoluble silk short fibers and soluble silk fibroins could form uniform composite films with a low coefficient of thermal expansion after being blended with sodium hyaluronate, which were named as insoluble silk film (ISH) and soluble silk film (SSH), respectively. The tensile strength of ISH could reach 138.8 MPa and SSH reached 153.9 MPa, which were 65.7 % and 30.5 % higher than that of the commercial control insoluble fibroin film (83.8 MPa) and commercial control soluble fibroin film (117.9 MPa), and 173.2 % and 203.0 % higher than that of pure hyaluronate film (50.8 MPa), respectively. Also, ISH and SSH had a modulus higher than 3 GPa. In this study, the low-concentration Na2CO3 method provides a simple and green technique for the preparation of high performance silk-hyaluronate composite materials.

Preparation and characterization of chitosan-based corn protein composites constructed with TG enzyme and their preservation performance on strawberries

This study describes the synthesis of Chitosan - corn protein (CSZ-TG) composites using TG enzyme (TG) as a cross-linking agent and the preparation of chitosan-based composite membrane material (CSZEO-TG) by blending citrus essential oil (EO) with the synthesized CSZ-TG. The prepared composite membrane material was used for fresh strawberry preservation and characterized by scanning electron microscopy, Fourier transform infrared spectroscopy, X-spectral diffraction, tensile properties, and water vapor and CO2 permeability. Scanning electron microscopy results showed a smooth surface of the composite membrane material after the addition of TG enzyme, while Fourier transforms infrared spectroscopy results showed a structural change of the composite membrane material after the addition of corn protein (Z). The tensile results showed an increase in the tensile strength of the composite membrane material after the addition of TG enzyme, while the flexibility of the composite membrane material was enhanced after the addition of EO. Compared with the pure chitosan membrane (CS), the water vapor and CO2 barrier properties of the composite membrane material after the addition of Z, TG, and EO did not change much, and they all showed better water vapor barrier properties. The results of the antioxidant analysis of the solution of the CSZEO-TG composite membrane material showed that the composite membrane material had efficient antioxidant properties. The effects of the composite film material on the storage period and quality of strawberries were evaluated by the indicators of weight loss, hardness, decay rate, soluble solids, titratable acid content, MDA content, and the content of four enzymes, SOD, POD, PPO and CAT. Comprehensive freshness data analysis showed that CSZEO-TG had the best freshness preservation performance and effectively extended the shelf life of strawberries.

Preparation of Positive and Negative Composite Electrode Materials for High-Performance Aqueous Asymmetric Supercapacitor by a Sequential Two-Step Reaction

Preparation of Positive and Negative Composite Electrode Materials for High-Performance Aqueous Asymmetric Supercapacitor by a Sequential Two-Step Reaction

Multiple birds with one stone: A new type of PPy/Fe3O4/rGO multifunctional composite fabric for wave absorption, UV resistance, anti-static and thermal insulation

To solve the problem of electromagnetic radiation pollution, it is especially important to develop electromagnetic wave-absorbing materials with excellent performance. The preparation of composite multifunctional textile materials with excellent wave-absorbing properties is one of the research hotspots for practical personal protection applications. In this work, PPy/Fe3O4/rGO polyester/cotton composite fabrics were prepared by impregnation, chemical reduction, chemical co-precipitation and in situ polymerization. When the thickness is 0.97 mm, the minimum reflection loss (RLmin) of PPy/Fe3O4/rGO polyester/cotton composite fabric is −12.12 dB, and the effective absorption bandwidth (EAB) is 4.7 GHz, which is excellent in wave absorption. Meanwhile, the PPy/Fe3O4/rGO polyester/cotton composite fabrics have excellent UV resistance (UV transmittance ratio of UVA and UVB bands as low as 0.02 %, UPF value of 100+), antistatic properties (static voltage half-life of 0.2 s), and excellent thermal management properties (thermal conductivity as low as 0.05796 W/(m·K)), and so on. The PPy/Fe3O4/rGO polyester/cotton composite fabrics prepared in this study are suitable for a variety of application scenarios, such as individual electromagnetic protection, individual protection in extremely cold environments, and individual heating physiotherapy, which is of great reference significance for the research of wearable individual protective textile materials.

Preparation of natural N/O/S co-doped biomass-derived carbon materials for supercapacitors using multistage gas self-exfoliation effect

High-value utilization of biomass provided a feasible way to solve the energy shortage and environmental problems. The preparation of micro-mesoporous composite carbon materials from biomass waste as feedstock using a multistage gas self-exfoliation mechanism (CH3COOK and Ca2(C2H5COO)2) was a feasible approach. Among them, the N, O and S co-doped carbon materials were obtained in this paper by using forestry waste (bamboo) as raw material, spiral algae as green heteroatom dopant, Ca2(C2H5COO)2 as multifunctional template agent, and CH3COOK as gentle activator. The results indicated that BC-SA-0.5CP exhibited 324.85 F/g at 0.5 A/g. The symmetric supercapacitor (BSC-0.5//BSC-0.5) achieved 96.02% capacitance retention after 10,000 cycles, indicating excellent rate performance and charge/discharge stability. At a power density of 162.5 W/kg, the BSC-0.5//BSC-0.5 had an energy density of 14.67 Wh/kg. In addition, it was deeply analyzed the growth mechanism of heteroatoms, the formation mechanism of porous carbon and the electron transfer routes, which provided a theoretical basis for the preparation of biomass-derived carbon materials. Overall, this study demonstrated that the multistage gas self-exfoliation mechanism was beneficial in promoting the formation of micro-mesoporous composite structures and the growth of heteroatom functional groups, which ultimately provided a new route for the synthesis of natural heteroatom-doped porous carbon.

Preparation of a Porous Protein-Based Composite Material by In Situ Polymerization of Pickering High Internal Phase Emulsion for Adsorption of Lead Ions.

The preparation of complex porous materials using a small molecular surfactant as the stabilizer of a high internal phase emulsion can result in harm to the environment. In this study, porous composites based on soy protein isolate with poly(acrylic acid) were prepared by in situ polymerization of a high internal phase monomer emulsion with an internal phase volume fraction of 80%. The material was prepared from acrylic acid and an N,N-methyl diacrylic acid monomer solution as the continuous phase, peanut oil as the dispersed phase, and soy protein isolate as the composite stabilizer. Scanning electron microscopy showed that porous composites exhibited a concave/convex three-dimensional interpenetrating pore structure. Fourier-transform infrared spectra revealed the existence of many active groups such as carboxyl, amino, hydroxyl, and sulfhydryl. The composite had a high adsorption capacity for lead ions, even at low concentration, with a removal rate of up to 95.7%. The adsorption process conformed to a two-stage model involving internal diffusion and Langmuir isothermal adsorption. The maximum saturated adsorption capacity was 36.71 mg/g when the initial solution concentration was 150 mg/L, the adsorbent concentration was 7.0 g/L, and the adsorption mechanism involved chemical interactions between the lead ions and the composite groups -COOH, -OH, and -SH.

Preparation and Application of Composite Phase Change Materials

With the popularity of lithium-ion batteries, thermal runaway accidents occur frequently. The importance of thermal management was becoming increasingly prominent. In this paper, a new composite phase change material (CPCM) was developed and applied to the thermal management of lithium-ion batteries. The chemical and microstructure of the material were deeply analyzed by scanning XRD and SEM. The thermal stability of the material was tested by using DSC and TG techniques. The thermal conductivity was exhaustively analyzed. The experimental results showed that CPCM containing 9% Aluminum phenylphosphinate exhibits optimal thermal storage performance and flame retardant efficiency, which effectively delayed and reduced the risk of thermal runaway in lithium batteries.

Immobilisation of ZnO nanoparticles on carbon and on glass fibres for visible light photocatalytic applications

Crystalline zinc oxide (ZnO) nanoparticles (NP) have been used for the evaluation of the effect of manganese doping on the photocatalytic performance towards the degradation of pharmaceutical products and for the preparation of photoactive composite materials based on fibres and ZnO.The presence of manganese effected on the particles size, as obtained by TEM analysis, and the impact on the crystallographic and optical properties was shown by XRD and DRS analysis. The multiple oxidation state of the doping manganese and its impact on the oxygen vacancies of the material, together with possibility of introducing energy levels in the forbidden zone and changes in the bandgap energy could contribute to improve the catalyst properties. However, and contrasting with some reported works, no advantage using the doped particles was observed on the photocatalytic response under UV or visible light irradiation.Later, the ZnO NP were immobilised by in situ hydrothermal approach on carbon and glass fibres and the composites show good nanoparticles coverage on the SEM images and the EDS, FTIR and DRS data are consistent with the presence of NP on the surfaces. Those composites have been successfully used for the degradation of the Diclofenac (DCF) and Carbamazepine (CMZ) pollutants. The complexity of the photodegradation under UV and visible light, due to the production of absorbing degradation products, was unveiled by UV–vis spectroscopy and HPLC analysis, and showed that distinct products may be detected during degradation, depending on the radiation used. The photostability of ZnO nanoparticles and the CF/ZnO composite maintaining 83 % of its initial efficiency after three cycles of reuse highlight the method's success in supporting nanoparticles on substrates and demonstrates promising applicability in fields such as environmental remediation.

Polymer dispersed cholesteric liquid crystals with combined photo- and mechanochromic response

The development of stimuli-sensitive systems is one of the newest and most promising directions in the field of modern materials science. The combination of various types of sensitivity in the same material opens the possibility of creating complex devices with a wide range of potential applications. This work deals with the design and preparation of new composite materials based on plasticized polyvinyl alcohol (PVA) films containing droplets of cholesteric liquid crystals (CLC). Mechanical stretching of elastic composite films results in a change in optical properties, namely selective light reflection (SLR), from CLC droplets. This in turn transforms the structure and optical properties of the entire polymer matrix. Such a process represents a certain mechano-optic response of the polymer matrix to the influence of mechanical deformation. The introduction of a chiral photochromic dopant into a composite film makes it possible to transform such a film into a photochromic material with the ability to control its optical properties using, for example, UV irradiation. Therefore, mechanical deformation of a polymer composite leads to a change in its optical properties (SLR) caused by a change chiral supramolecular structure of cholesteric mesophase. At the same time, UV irradiation of a polymer film induces E-Z isomerization process in the chiral photochromic dopant, altering its molecular shape and helical twisting power. This enables the using of this process for remote and contactless control of the composite optical properties. In addition, this feature allows one to implement the photopatterning and the recording of a latent image, which appears under the influence of a mechanical field.

New Advances in the Application of Bacterial Cellulose Composite Materials in the Field of Bone Tissue Engineering

Bacterial cellulose (BC) is a type of extracellular polymeric nanomaterial secreted by microorganisms over the course of their growth. It has gained significant attention in the field of bone tissue engineering due to its unique structure of three-dimensional fibrous network, excellent biocompatibility, biodegradability, and exceptional mechanical properties. Nevertheless, BC still has some weaknesses, including low osteogenic activity, a lack of antimicrobial properties, small pore size, issues with the degradation rate, and a mismatch in bone tissue regeneration, limiting its standalone use in the field of bone tissue engineering. Therefore, the modification of BC and the preparation of BC composite materials have become a recent research focus. Herein, we summarized the relationships between the production, modification, and bone repair applications of BC. We introduced the methods for the preparation and the modification of BC. Additionally, we elaborated on the new advances in the application of BC composite materials in the field of bone tissue engineering. We also highlighted the existing challenges and future prospects of BC composite materials.

Preparation of shape memory polyurethane composite materials by grafting PCL onto CNFs with different carboxyl content

This study describes the preparation of cellulose nanofibers (CNFs) with varying amounts of carboxyl groups from rice straw pulp using the TEMPO/NaBr/NaClO oxidation system. The resulting CNFs were found to be in the form of nanofibers with an average diameter of 6 nm and an average length of 160 nm. To further enhance their properties, the CNFs were grafted with polycaprolactone (PCL) to create CNFs-g-PCL, which was then blended with shape memory polyurethane (SMPU) to produce CNFs-g-PCL/SMPU composites. It was observed that as the carboxyl content in CNFs increased from 0.35 to 1.14 mmol/g, the graft ratio of PCL on CNFs decreased from 24.6 to 10.7%. Consequently, the hydrophobicity of the grafted product (CNFs-g-PCL) also decreased. When 10% CNFs-g-PCL was added to the SMPU matrix, the elastic modulus and tensile stress of the resulting composite were both higher than those of the pure SMPU, increasing by up to 54.4% and 67.3%, respectively. Additionally, the shape retention and shape recovery rates of the composite remained stable after addition of CNFs-g-PCL. In conclusion, incorporating CNFs-g-PCL into SMPU can improve its mechanical properties while maintaining its shape memory properties.Graphical abstract

Preparation of Sustainable Composite Materials from Bio‐Based Domestic and Industrial Waste: Progress, Problems, and Prospects‐ A Review

AbstractBio‐based waste from households and industries is a big problem for the world, however, turning it into valuable composite materials can offer a promising approach to deal with it. It involves the conversion of waste from different bio‐based sources such as cellulose waste from farming and forestry leftovers, chitin waste from seafood and mushrooms, and keratin waste from hair, nails, and feathers into natural fibers. These fibers are then effectively mixed with other materials to create composite materials having unique properties, such as high strength and stiffness, good thermal and electrical conductivity, and better barrier properties. Developing these materials is not just good for the environment because it reduces landfill waste and the reliance on non‐renewable resources, but it can also make economic sense for producers. In this review, the basic compounds of natural fibers and the development of composite materials from them are explored and discussed in detail. Furthermore, their chemical and mechanical properties are discussed and summarized. In the final section, a brief overview of the challenges and the future research needed in this fast‐evolving field is given.

Preparation and soldering performance of SAC305@Sn-bi Core-shell solder balls based on eutectic co-deposition

SnBi eutectic thin film alloys are widely used in microelectronic devices, sensors, biomedical devices due to their high resistance, low temperature coefficient, chemical stability, and biocompatibility. However, the large standard electrode potential difference (454 mV) between Sn (−0.136 V) and Bi (+0.3118 V) makes them difficult to be co-deposited, especially with eutectic composition. In this study, cathodic polarization curves were used to analyze the negative shift of the cathodic reduction potentials of Sn and Bi induced by gelatin and EDTA-2Na, respectively, which reduced the potential difference between the two to 184 mv (Sn:-0.958 v; Bi:-0.774 v) and enabled the co-deposition of Sn and Bi; cathodic overpotentials were analysed to show that catechol not only improves the degree of cathodic polarization, but also raises the overpotentials, resulting in flatter surface coatings; By adjusting the temperature, current density, and pulse current, a SnBi eutectic thin film coating with good weldability, controllable thickness, flat surface, density, and uniformity was obtained on copper foil using a platinum as the anode in a methanesulfonic acid solution. The results indicate that it is feasible to deposit SnBi solder alloy at eutectic points (Sn41.53Bi58.47, At.%). Under the synergistic effect of gelatin and unidirectional square wave pulse, a typical eutectic network morphology can be obtained, which is the same as the microstructure of industrial SnBi eutectic solder. Based on these, a core-shell composite soldering material for low-temperature soldering was obtained by using SAC305 solder balls as cores and a SnBi low-temperature soldering material coating was roll-plated on their surfaces. This study provides a reliable technical way and theoretical guidance for low-temperature soldering, preparation of low-temperature solderable core-shell composite soldering material, and application of sensors and optoelectronic devices.

Research Progress on the Preparation of Composite Materials by Resin Film Infusion (RFI)

The resin film infusion (RFI) process is a novel composite molding method for high-fiber content, excellent mechanical properties, low porosity, and adjustable thickness. This review examines two common resin materials used in the RFI process: bismaleimide resin (BMI) and epoxy resin. Furthermore, numerical simulation methods for isothermal and non-isothermal processes in the RFI process are described, focusing on the analysis of the mathematical model of resin flow. Finally, it covers the unique properties of RFI composites and showcases the RFI process’s cost-effectiveness and functionality in fabricating composite structures for various applications. The limitations and potential future developments of RFI process molding technology are also summarized.

Preparation and properties of transparent, waterproof, and antibacterial composite film materials

AbstractTransparent polymer materials, such as plastics, have become widely used in the packaging industry due to their excellent properties. However, their nondegradability has led to a significant environmental issue known as “white pollution.” To address this issue, a transparent antibacterial film material was prepared using carboxymethyl cellulose and carboxymethyl chitosan as raw materials through an acid‐assisted freeze–thaw strategy. The material exhibits optical transmittance exceeding 90% and a tensile strength of up to 124.1 MPa. Meanwhile, this material demonstrated excellent waterproof performance as well as antibacterial activity to Staphylococcus aureus and Escherichia coli. Therefore, this film material holds promising potential for development in antibacterial food packaging.