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Polymer‐derived ceramics (PDCs) remain at the forefront of research for a variety of applications including ultra‐high‐temperature ceramics, energy storage and functional coatings. Despite their wide use, questions remain about the complex structural transition from polymer to ceramic and how local structure influences the final microstructure and resulting properties. This is further complicated when nanofillers are introduced to tailor structural and functional properties, as nanoparticle surfaces can interact with the matrix and influence the resulting structure. The inclusion of crystalline nanofiller produces a mixed crystalline–amorphous composite, which poses characterization challenges. With this study, we aim to address these challenges with a local‐scale structural study that probes changes in a polysiloxane matrix with incorporated copper nanofiller. Composites were processed at three unique temperatures to capture mixing, pyrolysis and initial crystallization stages for the pre‐ceramic polymer. We observed the evolution of the nanofiller with electron microscopy and applied synchrotron X‐ray diffraction with differential pair distribution function (d‐PDF) analysis to monitor changes in the matrix's local structure and interactions with the nanofiller. The application of the d‐PDF to PDC materials is novel and informs future studies to understand interfacial interactions between nanofiller and matrix throughout PDC processing. [ABSTRACT FROM AUTHOR]

Bast fiber-reinforced polymer composites (BFRPs) are grabbing considerable research attention due to their assertive impact on the environment and excellence in biodegradability. Though BFRPs have excellent ecological performance factors, they also lack in some cases, such as lower mechanical, electrical, and thermal properties, due to the significant moisture absorption, minimal thermal stability, and inherent nature of bast fibers. BFRPs exhibit weaker fiber/matrix interfacial adhesion as compared to synthetic fiber-reinforced polymer composites, resulting in lower mechanical properties. Nowadays, a wide variety of fiber and matrix modification techniques are practiced improving the fiber-matrix interaction, which ultimately improves the mechanical properties. Among the fiber and matrix modification techniques, nanofiller integration is the most promising one. This study reviews the impacts of introducing carbon-based nanofillers, particularly graphene and carbon nanotubes (CNT), in diversified BFRPs. The influence of carbon-based nanofillers on the mechanical, electrical, and thermal behavior of BFRPs and their potential prospects are comprehensively reviewed. The paper concludes with the challenges and difficulties in composite processing, along with the techniques for overcoming them. [ABSTRACT FROM AUTHOR]

Over the past years, poly(lactic acid) or polylactide (PLA) is commonly researched as a possible replacement for traditional fossil‐based polymers because of its compostability, biocompatibility, and high mechanical properties. PLA has a variety of applications in packaging, biomedical, and structural. However, PLA has limitations, such as high brittleness, low thermal stability, and a slow crystallization rate, which limits the wide range of applications. To overcome these limitations, the literature reports that blending PLA with other polymers, such as poly(ε‐caprolactone) (PCL), is an economically viable approach. Although blending PLA with PCL is considered a feasible approach, the blend system still suffers from immiscibility, depending on the blend composition. This review aims to highlight recent developments from 2014 to date on the processing of PLA/PCL blends, including their composites, with a primary focus on morphological characteristics and mechanical and thermal properties, including their potential applications in various sectors. [ABSTRACT FROM AUTHOR]

Bismuth ferrite (BiFeO3, BFO) is one of the few single-phase crystalline compounds exhibiting strong multiferroic properties at room temperature, which makes it promising for use in various fields of science and technology. The remarkable characteristics of BFO at the nanoscale position it as a compelling candidate for enhancing the functionalities of polymeric nanocomposite materials. In this study, we explore the fabrication of polyvinylidene fluoride (PVDF) nanocomposites with a variable content of BFO nanopowders (0, 5, 10, 15, 20, and 25 wt%) by solution casting in the form of thin films with the thickness of ~60 µm. Our findings reveal that the presence of BFO nanoparticles slightly facilitates the formation of β- and γ-phases of PVDF, known for their enhanced piezoelectric properties, thereby potentially expanding the utility of PVDF-based materials in sensors, actuators, and energy harvesting devices. On the other hand, the increase in filler concentration leads to enlarged spherulite diameter and porosity of PVDF, as well as an increase in filler content above 20 wt% resulting in a decrease in the degree of crystallinity. The structural changes in the surface were found to increase the hydrophobicity of the nanocomposite surface. Magnetometry indicates that the magnetic properties of nanocomposite are influenced by the BFO nanoparticle content with the saturation magnetization at ~295 K ranging from ~0.08 emu/g to ~0.8 emu/g for samples with the lowest and higher BFO content, respectively. [ABSTRACT FROM AUTHOR]

PDMS-based aerogel layers were synthesized as insulation layers by adopting mullite fiber (MF), hollow glass microspheres (HGM) and silica aerogel (SA) as the main fillers, and their loading amounts and content ratios were checked to investigate their effects on the thermal insulation properties in PDMS composites by thermal conductivity, thermal stability, and thermal insulation. The loading amount of nanofillers can significantly influence the insulation-layer performance, and the best performance with the lowest thermal conductivity of 0.0568 W/(m·K) was obtained by 10 wt% loading in PDMS with MF:SA:HGM = 2:2:1, which can achieve a temperature difference (∆T) of 67 °C on a 200 °C hotplate. Moreover, the variation of the filler content ratios can also affect the thermal insulation behavior when the loading amount is fixed at 10 wt%, and the best thermal barrier performance can be found for the sample with more SA as the filler (MF:SA:HGM = 1:3:1). The formed sample had the best thermal stability and thermal insulation property, which can stand a 9 min flame test without burning by butane spray gun, and the backside of the sample showed ∆T > 500 °C for the whole test. [ABSTRACT FROM AUTHOR]

[Display omitted] The presence of emerging organic micropollutants (OMPs) in drinking and potable waters is a matter of great concern due to the health hazards associated with these. In this work, we present the preparation and application of a thin-film nanocomposite (TFN) membrane containing functionalized graphene oxide to effectively remove low-molecular-weight OMPs from water. Graphene oxide was functionalized with amino silane to enhance its cross-linking capability during the formation of the polyamide active layer via interfacial polymerization of diethylene triamine and trimesoyl chloride. The TEM analysis showed that amino silane functionalized GO had 2–3 layered sheets, while non-functionalized graphene oxide appeared multilayered or stacked. XPS analysis confirmed the successful functionalization of GO. Characterization of the membranes with advanced techniques confirmed the successful incorporation of the GO and its functionalization: spectra from Fourier Transform Infra Red spectroscopy had the characteristic peaks of GO and N H groups; scanning Electron Microscopy (SEM) images showed a continuous presence of GO nanosheets. Contact angle measurements showed the TFN membranes to be more hydrophilic than their thin film composite (TFC) counterparts. Incorporating functionalized oxide nanosheets in the active polyamide layer produced additional water permeation channels, resulting in an improvement of ∼25 % in permeate flux compared to the pristine TFC and the TFN membrane with non-functionalized GO. The removal efficiencies of four OMPs commonly found in natural waters: Amitriptylene HCl (ATT HCl) and Bisphenol-A (BPA), Acetaminophen (ACT), and Caffeine (CFN) were determined for the synthesized membranes. The TFN membrane with functionalized GO outperformed its TFC counterpart with ∼100 % removal for BPA, ∼ 90 % for CFN and ATT HCl, and ∼80 % removal for the low molecular weight ACT. The high-efficiency rejection of OMPs was attributed to the synergistic effects of size exclusion as well as the reduced specific interactions between the functional groups. [ABSTRACT FROM AUTHOR]

Composite materials are being developed to improve the physical and mechanical properties of matrix polymers. Commercialized polymer composites possess high strength, even though they are not biocompatible by nature. The present study concentrates on developing an innovative composite that would be highly biodegradable. Orange peel was chosen as a filler material due to its significant properties to mix with the polylactic acid (PLA) matrix. PLA composites composed of orange peel reinforcements would be a sustainable composite that does not harm the ecological conditions. Orange peel-reinforced PLA was manufactured in filament form at three different concentrations, such as 5, 15, and 25 wt.%. Single fibre tensile test was also conducted for all composites along with PLA. Results revealed that tensile strengths of composites were observed to be higher than that of PLA. Scanning electron microscopy (SEM) images were captured at surfaces of failed filaments, and uniformly distributed fillers were observed in the PLA matrix. Tensile, compression, and flexural tests were conducted on the additively fabricated PLA and composite specimens. It is observed that PLA composite containing 15 wt.% orange peel reinforcement possesses better mechanical properties than other composites. This research work would help transform the waste material (orange peel) into a valuable product for sustainable growth. [ABSTRACT FROM AUTHOR]

AbstractFoldability capacity is now introduced as a novel nanofiller reinforcement production procedure using some operation to control the mechanical, thermal and electrical properties in the sport equipment. Application of this type of nanofillers in the curved structures like pole vault shell leads to a novel engineering and sport shell shape structures. This article is organized to suggest a vibration-based formulation for analysis of folded reinforced curved shell sport structure subjected to thermal and mechanical loading. Using computation of kinetic, strain and external energies, one can arrive the motion’s equations using the minimization of total energy and Hamilton’s principle. Using solution of the motion’s equations through an analytical approach, the parametric analysis is presented. The verified test is presented for confirmation of the solution and trend of results. [ABSTRACT FROM AUTHOR]

Due to their light weight, high specific strength, and low cost, polymer composite (PC) materials are used in a variety of industrial and home applications. An appropriate nanofiller can be used to improve the different performances of polymer composites. The present study gives an insight into the use of nanofillers in polymer composites, and their influence on the performance of polymer composites is summarized. The broad classification of processing routes of nanofiller and nanofiller-based polymer composites is also presented. As we are moving towards a greener society, the biodegradability of the polymer composites and their suitability along with the life cycle stages of PCs are also highlighted. Although nanofillers significantly improve the overall performance of biocomposites, excessive use of nanofillers is not recommended. The nanotoxicity associated with excessive use of nanofillers is addressed, and the emerging applications of nanofiller-based biocomposites are also discussed. [ABSTRACT FROM AUTHOR]

Background: Environmental concerns about petroleum-based plastic packaging materials and the growing demand for food have inspired researchers and the food industry to develop food packaging with better food preservation and biodegradability. Nanocomposites consisting of nanofillers, and synthetic/biopolymers can be applied to improve the physiochemical and antimicrobial properties and sustainability of food packaging. Scope and approach: This review summarized the recent advances in nanofiller and their applications in improved food packaging systems (e.g., nanoclay, carbon nanotubes), active food packaging (e.g., silver nanoparticles (Ag NPs), zinc oxide nanoparticles (ZnO NPs)), intelligent food packaging, and degradable packaging (e.g., titanium dioxide nanoparticles (e.g., TiO2 NPs)). Additionally, the migration processes and related assessment methods for nanofillers were considered, as well as the use of nanofillers to reduce migration. The potential cytotoxicity and ecotoxicity of nanofillers were also reviewed. Key findings: The incorporation of nanofillers may increase Young's modulus (YM) while decreasing the elongation at break (EAB) (y = −1.55x + 1.38, R2 = 0.128, r = −0.358, p = 0.018) and decreasing the water vapor (WVP) and oxygen permeability (OP) (y = 0.30x − 0.57, R2 = 0.039, r = 0.197, p = 0.065). Meanwhile, the addition of metal-based NPs could also extend the shelf-life of food products by lowering lipid oxidation by an average of approx. 350.74% and weight loss by approx. 28.39% during the longest storage period, and significantly increasing antibacterial efficacy against S. aureus compared to the neat polymer films (p = 0.034). Moreover, the migration process of nanofillers may be negligible but still requires further research. Additionally, the ecotoxicity of nanofillers is unclear, as the final distribution of nanocomposites in the environment is unknown. Conclusions: Nanotechnology helps to overcome the challenges associated with traditional packaging materials. Strong regulatory frameworks and safety standards are needed to ensure the appropriate use of nanocomposites. There is also a need to explore how to realize the economic and technical requirements for large-scale implementation of nanocomposite technologies. [ABSTRACT FROM AUTHOR]

The work represents the results of experimental research on the influence of the nanofiller’s nature on the thermal physical properties of composite materials. Polymer composite materials based on epoxy diane oligomer ED-20 were modified by 4-aminobenzoic acid. Martens yield temperature was researched and the glass transition temperature of the developed materials was determined. For the establishment of the thermal field’s effect on the structural processes of composite materials, the thermal coefficient of linear expansion of the materials was researched. Due to the necessity of studying the influence of temperature on physical-chemical processes and transformations in polymer composites, modern thermal analysis methods were used – differential thermal and thermal gravimetric analysis. Based on the analysis of experimental data, the optimal content of 4-aminobenzoic acid q  0.10 wt.% was determined per 100 wt.% of the ED-20 oligomer, which leads to the improvement of thermal physical properties of epoxy composite materials. [ABSTRACT FROM AUTHOR]

Ethylene propylene diene monomer (EPDM) is a synthetic rubber widely used in industry and commerce due to its high thermal and chemical resistance. Nanotechnology has enabled the incorporation of nanomaterials into polymeric matrixes that maintain their flexibility and conformation, allowing them to achieve properties previously unattainable, such as improved tensile and chemical resistance. In this work, we summarize the influence of different nanostructures on the mechanical, thermal, and electrical properties of EPDM-based materials to keep up with current research and support future research into synthetic rubber nanocomposites. [ABSTRACT FROM AUTHOR]

Starch based bioplastics were prepared and characterized with fillers carboxy methyl cellulose (CMC), chitosan (CS) and nanochitosan (NCS); plasticizer sorbitol and cross‐linking agent citric acid (CA) at different loading levels. Structural, water resistance, water vapor permeability, solubility, mechanical, antimicrobial and biodegradation properties of the bioplastics were investigated. FTIR confirmed bonding of starch with cross‐linking agent, fillers and plasticizer. The water uptake of the CMC bioplastics was decreased up to 70 % with 20 % CA addition. Bioplastics with CS and NCS showed lesser water uptake, only 12.5 % for CS bioplastic. The water vapour permeability (WVP) of all bioplastics was low in the range 2.16×10−7–6.29×10−7 gday−1 m−1 Pa−1. The CA addition increased water resistance and lowered WVP of the bioplastics by restricting the hydrophilic functional groups and forming more tight structures. The fillers CS and NCS additions enhanced the mechanical strength attributing to more hydrogen bonding between NH3+ of chitosan and OH− of starch. All bioplastics demonstrated good antimicrobial activities. These bioplastics offer an attractive alternative to non‐biodegradable plastics used in food packaging due to its enhanced water resistance, antibacterial properties and biodegradability. [ABSTRACT FROM AUTHOR]

AbstractThis mini-review investigates the effect of numerous surface treatments and the influence of incorporating organic/inorganic nanofillers into polymeric adhesives on the shear behaviour of adhesive-bonded single-lap joints. Surface treatment of the adherend surface and nanofiller reinforcement on the adhesive has enhanced the shear strength of adhesive-bonded joints. This study examined numerous nanofillers (CBs, GNPs, MWCNTs, CNH, MMT, SNPs, RGO, GO, GNOP, and ceramic fillers) reinforcement with varying weight percentages (0–3%) and surface preparation techniques such as grid blasting, acetone cleaning, sandpaper roughing, acid etching, etc. It has been observed that the surface treatment techniques and the addition of nanofillers enhanced the cohesive and adhesive forces between the adherend and the adhesive, causing the adherend and adhesive to mechanically interlock in the overlapping zone. Moreover, 10 phr of organo-modified montmorillonite (MMT) filled epoxy exhibited excellent shear strength among the myriad organic/inorganic nano filler-modified adhesive joints. This critical Mini-Review will open new avenues in adhesive-bonded single-lap joint research. [ABSTRACT FROM AUTHOR]

Recently, there has been an increasing demand for the utilization of hybrid basalt/glass fiber epoxy composites with nanofillers in various structural applications. These materials have become increasingly popular because of their outstanding qualities, such as their impressive strength-to-weight ratio, improved stiffness, resistance to corrosion and chemicals, and environmentally friendly properties. This study aims to examine the morphological, mechanical, and dynamic mechanical performances of basalt/E-glass fiber-reinforced epoxy infused with equal proportions of Multiwalled Carbon Nano Tubes (MWCNTs) and Silicon dioxide (SiO2) nanoparticles at varying weight percentages (0, 1, 2, and 3) according to ASTM standards. The composite laminates were fabricated using a manual lay-up method and compression molding. A novel stacking sequence of fibers 01B/02G/02B/02G/02B/02G/01B, comprising 12 layers, was employed. The tensile strength, tensile modulus, Inter-Laminar Shear Strength (ILSS), and glass transition temperature (Tg) of BG3 (2%) composite specimen were increased from 247 to 308 MPa, 19.89GPa to 24.60GPa, 23.8 MPa to 40 MPa, and 730C to 900C respectively. The results demonstrate notable enhancements in tensile strength, tensile modulus, ILSS, and Tg of 2wt. % MWCNTs + SiO2 filled BG3 (2%) composite compared to the unfilled composite by 20%, 20%, 41%, and 18%, respectively. The addition of MWCNTs + SiO2 nanofillers in composites resulted in a significant enhancement of mechanical and dynamic mechanical performances compared to the unfilled composite. It is concluded that the addition of a minimal amount of MWCNTs and SiO2 to the matrix results in significantly improved performance compared to the unfilled composite. The Scanning Electron Microscopy images provide clear evidence of the primary failure mechanisms in composites, including debonding, matrix cracks, fiber pull-outs, and fiber fracture. [ABSTRACT FROM AUTHOR]

Research to replace petroleum-based plastics has been quite challenging. Currently, there is a lot of interest in biopolymers as an alternative. However, biopolymers do not have suitable mechanical properties when in film form, which limits their applications. To resolve this issue, clay minerals are being incorporated as a strategy. Clay minerals offer the films good barrier, thermal, rheological, optical, and mechanical properties. They can also work with other additives to promote antioxidant and antimicrobial activity. This brief review focuses on incorporating clay minerals with other nanofillers and bioactives to improve their physical, chemical, and functional characteristics. The synergy of these materials gives the films exceptional properties and makes them suitable for applications such as food coatings, packaging materials, dressings, and bandages for treating skin wounds. [ABSTRACT FROM AUTHOR]

The tensile strength of polymer composites is basically influenced by the geometry (size and shape) of the reinforcing material as well as interfacial interaction and bonding between the polymer matrix and reinforcing phase. This work compares the effect of microfillers to nanofillers of coconut husk, bamboo and cotton linter on the tensile strength and microstructure of vulcanized rubber matrix. The various composites were formulated and prepared using filler loading of 5, 10, 15, 20, 25 and 30 parts per hundred of rubber (pphr) in rubber matrix for both micro- and nano- fillers of the various biomass through friction shearing and compression moulding processes. Results revealed that the tensile strength of the nanocomposites predominantly increased from 1.85 MPa for neat sample to maximum values of 3.83, 3.16 and 3.85 MPa respectively for composites with 25pphr of coconut husk cellulosic nanoparticles (NR-CHNC25), 30pphr of bamboo cellulosic nanoparticles (NR-BNC30) and with 25pphr of cotton linter cellulosic nanoparticles (NR-CLNC25) conversely, the tensile strength of their counter microcomposites changes from 1.85MPa for neat sample to maximum values of 1.68, 1.67 and 2.46 MPa for composites with 10pphr of coconut cellulosic microparticles (NR-CHMC10) 15pphr of bamboo cellulosic microparticles (NR-BMC15) and 30pphr of cotton linter cellulosic microparticles (NR-CLMC30) respectively within the loading range employed in this experiment. Scanning Electron Microscope (SEM) images of microcomposites showed cases of microfiller debonding and pull-out from the rubber matrix. Hence the improved tensile strength of nanocomposites over their counterpart microcomposites was attributed to the larger surface area provided by nanofillers for interfacial bonding and effective stress transfer. [ABSTRACT FROM AUTHOR]

Metal sulfide nanoparticles have recently attracted much attention due to their unique physical and functional properties. Metal sulfide nanoparticles used as optoelectronic and biomedical materials in the past decades are promising for making functional nanocomposite films due to their low toxicity and strong antibacterial activity. Recently, copper sulfide and zinc sulfide nanomaterials have been used to produce food packaging films for active packaging. Metal sulfide nanoparticles added as nanofillers are attracting attention in packaging applications due to their excellent potential to improve mechanical, barrier properties, and antibacterial activity. This review covers the fabrication process and important applications of metal sulfide nanoparticles. The development of metal sulfides reinforcing mainly copper sulfide and zinc sulfide nanomaterials as multifunctional nanofillers in bio-based films for active packaging applications has been comprehensively reviewed. As the recognition of metal sulfide nanoparticles as a functional filler increases, the development and application potential of active packaging films using them is expected to increase. [ABSTRACT FROM AUTHOR]

Presently, the food industry continues to be major contributor of plastic waste across the globe. The food industry is in great demand of sustainable food packaging material due to increase environmental and health consciousness. Biobased polymers which are degradable promise to be a key solution. Use of nanotechnological advancements in biopolymers provide a wide range of additional benefit and makes them a suitable packaging material. The benefits include barrier to oxygen permeability, moisture permeability, crystalline structure, other barrier properties, morphology, thermal stability, optical properties, mechanical properties, improving shelf life of the packaged food and antimicrobial characteristics. Polymeric materials (matrix) have been infused with nanofillers such as silicates, carbon, cellulose and starch nanoparticles. This review aims to focus on new and effectual polymeric materials for food packaging that are technologically advanced with nanotechnology as a solution to the challenges faced by food industry with regard to the product safety and materials performance. [ABSTRACT FROM AUTHOR]

The study herein is directed toward the tuning of various properties of recyclable and biocompatible polymer: chitosan (CS) via incorporating the variable wt% of r‐GO in the polymer. The CS/r‐GO polymer nanocomposites (PNCs) are prepared in the form of free‐standing film by solution mixing and casting technique. To search the potential applications, the prepared PNCs are characterized in terms of structural, photoluminescence (PL), surface morphology, optical, and Raman spectra. The crystalline size and microstrain both are enhanced with rise in wt% of r‐GO nanofiller. Raman spectra confirm that as the wt% of r‐GO increases, there is a minor shift toward a smaller wavenumber in the locations of the D, G, and 2D bands, while the intensity ratios (ID/IG$\left(\right. I_{\text{D}} / I_{\text{G}}$) increase. Field‐emission scanning electron microscopy results are capable of offering details regarding the surface quality for the interface purposes. The characteristic peaks and their broadening in PL spectra, chromaticity coordinates, dominant wavelength, and correlated color temperature are altered with variation of r‐GO wt.%. The optical bandgap, refractive index, and Urbach energy are found to tune with varying the nanofiller wt.%. These results suggest that CS/r‐GO PNC may be the potential candidate for possible application in fabricating the tunable optoelectronic devices. [ABSTRACT FROM AUTHOR]

MXenes are a group of 2D transition metal carbonitrides, nitrides and carbides that have become widely recognized as useful materials since they were first discovered in 2011. MXenes, with their exceptional layered structures and splendid external chemistries, have excellent electrical, optical, and thermal properties, making them suitable for catalysis, biomedical uses, environmental remediation, energy storage, and EMI shielding. Over forty MXene compounds with surface terminations like hydroxyl, oxygen, or fluorine are hydrophilic and easily integrated into various applications. Advanced synthesis methods, including selective etching and etchant modifications, have broadened MXene surface chemistries for customized mechanical, thermal, and electrical applications. Integrating MXenes into polymer composites has demonstrated notable promise, enhancing the host polymers' electrical conductivity, thermal stability and mechanical strength. The MXene-polymer composites demonstrate remarkable prospective on behalf of advanced purposes, including flexible electronics, high-performance EMI shielding materials, and lightweight structural components. MXenes have the desirable characteristic of being able to create flexible and translucent films, as well as improve the properties of polymer matrices. This makes them very suitable for use in advanced technological applications. This review summarizes MXene research, methods, and insights, highlighting key discoveries and future directions. This also highlights the importance of ongoing research to fill in the gaps in current knowledge and improve the practical uses of MXenes.

Abstract Over the past years, poly(lactic acid) or polylactide (PLA) is commonly researched as a possible replacement for traditional fossil‐based polymers because of its compostability, biocompatibility, and high mechanical properties. PLA has a variety of applications in packaging, biomedical, and structural. However, PLA has limitations, such as high brittleness, low thermal stability, and a slow crystallization rate, which limits the wide range of applications. To overcome these limitations, the literature reports that blending PLA with other polymers, such as poly(ε‐caprolactone) (PCL), is an economically viable approach. Although blending PLA with PCL is considered a feasible approach, the blend system still suffers from immiscibility, depending on the blend composition. This review aims to highlight recent developments from 2014 to date on the processing of PLA/PCL blends, including their composites, with a primary focus on morphological characteristics and mechanical and thermal properties, including their potential applications in various sectors.

Abstract Biodegradable polymer nanocomposites (BPNCs) are advanced materials that have gained significant attention over the past 20 years due to their advantages over conventional polymers. BPNCs are eco-friendly, cost-effective, contamination-resistant, and tailorable for specific applications. Nevertheless, their usage is limited due to their unsatisfactory physical and mechanical properties. To improve these properties, nanofillers are incorporated into natural polymer matrices, to enhance mechanical durability, biodegradability, electrical conductivity, dielectric, and thermal properties. Despite the significant advances in the development of BPNCs over the last decades, our understanding of their dielectric, thermal, and electrical conductivity is still far from complete. This review paper aims to provide comprehensive insights into the fundamental principles behind these properties, the main synthesis, and characterization methods, and their functionality and performance. Moreover, the role of nanofillers in strength, permeability, thermal stability, biodegradability, heat transport, and electrical conductivity is discussed. Additionally, the paper explores the applications, challenges, and opportunities of BPNCs for electronic devices, thermal management, and food packaging. Finally, this paper highlights the benefits of BPNCs as biodegradable and biodecomposable functional materials to replace traditional plastics. Finally, the contemporary industrial advances based on an overview of the main stakeholders and recently commercialized products are addressed.

Natural fiber-reinforced polymer matrix composites recently got great attention in biomedical applications due to their inherent characteristics such as biocompatibility, lightweight, and biodegradability. However, natural fiber composites suffer from poor mechanical properties and weak interfacial adhesion. It is well documented that the addition of nanofiller has improved the mechanical properties of different synthetic fibers such as glass and carbon composites. The main objective of this paper is to study nanofillers' effect on the mechanical properties of unidirectional false banana fibers reinforced polymer composites. The filler materials, crystalline nanocellulose fibrils, and crystalline nanosilica particles were extracted from sugarcane bagasse and its byproducts. The composite samples were fabricated by adding the nanofillers in unidirectional natural fibers arranged in four fiber orientations (0°, 0o/90o ±45o, and quasi-isotropic), and their tensile, flexural, compression strength, thermal stability, and void content were measured following ASTM standards. The results revealed that adding nanofillers increased the tensile, flexural, and compressive strengths by 16 % (98.83 Mpa), 11 % (161.60 Mpa), and 23 % (114.62 Mpa), respectively. Similarly, at 0° orientation, the addition of nanoparticles enhances the tensile, bending, and compressive modulus by 30 % (15.43 Gpa), 12 % (13.52 Gpa), and 60 % (42.6 Gpa), respectively. On the other hand, the void content was reduced with the addition of nanofillers. The results also revealed that composites with crystalline nanosilica particle fillers had superior thermal stability compared to crystalline nanocellulose fibril fillers. The overall results of this research give the confidence that nano particle-filled natural fiber composites can be used for bio-based engineering applications, such as prosthetic sockets.

In natural fiber polymer composites (NFPCs), void formation is a typical issue that degrades the composite physical and mechanical properties and limits their uses in aerospace, automobiles, construction, and marine applications. This study uses 50-nm-sized alumina (Al2O3) and magnesia (MgO) nanofillers with epoxy resin to manufacture flax/PLA and jute composites by vacuum bagging technique. The Al2O3 and MgO nanofiller loading in epoxy composites ranged from 0 to 4 wt.% with a 1 wt.% gap. SEM was utilized to examine the morphology and interfacial bonding of the fiber matrix in composites. As the nanofiller loading in the composites grew, the fiber volume fraction decreased with the increase in the density and void content %. MgO filled laminates have shown higher void content than Al2O3 filled laminates due to their low theoretical density, which is inversely proportional to the voids content percentage. Jute-reinforced laminates have shown less fiber volume fraction and higher void content than flax/PLA-reinforced laminates due to the jute fiber's high density. The SEM images of the generated laminates show voids, cracks, fiber breakage, bending, and pull-out moieties. [ABSTRACT FROM AUTHOR]

The pairs of nanofillers prepared by graphene nanoplatelets (GNPs) and multi-walled carbon nanotubes (MWCNTs) were added to the epoxy matrix in various ratios to produce hybrid epoxy nanocomposites. The effects of the presence of these nanofillers at 0.1–0.4 wt.% on the mechanical and thermal properties were tested. Likewise, carbon fiber reinforced MWCNT/GNP modified epoxy nanocomposite laminates were also manufactured and tested. The dispersion of nanofiller in the polymer matrix was evaluated by Scanning Electron Microscopy (SEM). It was determined that the hybrid composite consisting of a MWCNT:GNP ratio of 1:3 and a nanofiller ratio of 0.3 wt.% showed the best mechanical properties with a tensile strength of 75.1 MPa. The presence of GNPs and MWCNT nanofillers in epoxy/carbon fiber laminates influenced positively the tensile strength and strain but negatively the elastic modulus. Glass transition temperature of epoxy increased from 87.25°C to 114.67°C for MWCNT:GNP ratio of 1:1 (0.3 wt.%). [ABSTRACT FROM AUTHOR]

Biodegradable polymer nanocomposites (BPNCs) are advanced materials that have gained significant attention over the past 20 years due to their advantages over conventional polymers. BPNCs are eco-friendly, cost-effective, contamination-resistant, and tailorable for specific applications. Nevertheless, their usage is limited due to their unsatisfactory physical and mechanical properties. To improve these properties, nanofillers are incorporated into natural polymer matrices, to enhance mechanical durability, biodegradability, electrical conductivity, dielectric, and thermal properties. Despite the significant advances in the development of BPNCs over the last decades, our understanding of their dielectric, thermal, and electrical conductivity is still far from complete. This review paper aims to provide comprehensive insights into the fundamental principles behind these properties, the main synthesis, and characterization methods, and their functionality and performance. Moreover, the role of nanofillers in strength, permeability, thermal stability, biodegradability, heat transport, and electrical conductivity is discussed. Additionally, the paper explores the applications, challenges, and opportunities of BPNCs for electronic devices, thermal management, and food packaging. Finally, this paper highlights the benefits of BPNCs as biodegradable and biodecomposable functional materials to replace traditional plastics. Finally, the contemporary industrial advances based on an overview of the main stakeholders and recently commercialized products are addressed. [ABSTRACT FROM AUTHOR]

In recent years, the need to use environmentally friendly materials has also triggered increased activity of research and development on water-based formulations for films and coatings. In an effort to meet this goal, waterborne polyurethanes (WBPUs) were developed, which during the coating deposition or the formation of self-standing films release innocuous water to the atmosphere instead of volatile organic compounds (VOCs), as is the case with most traditional solvent-based polymers. One of the most studied applications for this type of materials is water-based paints and coatings. Advances in the development of WBPU have been produced through the careful selection of different sources of hydroxyl group components, as well as different types of chain extenders and emulsifiers. On the other hand, to improve the performance required to the final application composite formulations have been tailored through the addition of organic and inorganic particles/nanoparticles. This review focuses on the relation between formulation-structure and properties of these materials from the initial dispersions to the final coating films. Most commonly used methods of application and their relation to the viscosity of the dispersions have also been briefly considered. [ABSTRACT FROM AUTHOR]

To incorporate sustainability in polymer composites, industries prefer natural fibers as reinforcement material owing to its specific mechanical properties. This study investigates the characterization of sodium hydroxide–treated Agave Tequilana Fibers (ATFs) reinforced in unsaturated polyester resin (UPR) matrix composite with nanosized Silicon Carbide (SiC) particles as filler material. The composite specimens were manufactured by compression moulding technique. The alkali-treated ATF (AATF) reinforced composite (AATFC) specimens with 40 wt.% of AATF were impregnated with different wt.% SiC nanoparticles as 1 wt.%, 2 wt.% and 3 wt.%. The effect of wt.% of SiC nanoparticles on mechanical, wear and moisture absorption characteristics of AATFC specimens were described. It was found that AATFC specimens with 2 wt.% SiC nanoparticles exhibit maximum hardness value of 87 HRRW, tensile strength of 51.61 MPa, flexural strength of 61.73 MPa, and impact strength of 8.17 J/cm2. Similarly, the same composite specimen incurred a minimum wear weight loss of 0.013 g and moisture absorption characteristics with increase in weight of 0.016 g in normal water, 0.017 g in sea water, and 0.011 g in NaOH solution. On the other hand, agglomeration of SiC nanoparticles and its heterogeneous distribution in AATFC with 3 wt.% SiC nanoparticles resulted in declined properties. Also, the fractographic images of tensile failure cross-section of AATFC specimens help to estimate the interaction between UPR, AATF and SiC in the composites. The observed results favour the use of AATFC specimen in light weight structural applications. [ABSTRACT FROM AUTHOR]

Composite industries use natural fibre as a sustainable resource to improve the sustainability and eco-friendliness of polymer composites. The characterization of alkali-treated Moringa oleifera fruit husk fibres (AMOFHFs) reinforced in unsaturated polyester resin matrix with varying weight percent of nano-sized silicon carbide (SiC) particles as filler material is presented in this paper. The AMOFHFs reinforced composite (AMOFHFC) specimens contain 20 wt.% AMOFHFs and nano-sized SiC particles ranging from 1 to 5 wt.% in 1 wt.% steps. The effect of wt.% variation in nano-sized SiC particles on the mechanical, morphological, tribological and water absorption behaviour of AMOFHFC specimens was thoroughly investigated. According to the findings, the AMOFHFC specimen with 4 wt.% nano-sized SiC particles as filler material has the best mechanical, tribological and water absorption properties. The hardness, tensile, flexural and impact strength of the AMOFHFC specimen with 4 wt.% nano-sized SiC particles improved by 14.86%, 23.11%, 9.6% and 23.22% respectively compared to the composite specimen without SiC nanoparticles as filler material. Similarly, the AMOFHFC specimen with 4 wt.% nano-sized SiC particles exhibited a lesser weight loss of 96.7% compared to the composite specimen without SiC nanoparticles as filler material during the Pin-on-disk experimentation which showcases its superior tribological characteristics. Furthermore, SEM images of fractured tensile AMOFHFC specimens aided in understanding the bonding nature of the AMOFHFs, SiC nanoparticles and unsaturated polyester resin matrix in the composite specimens. The findings above led us to the conclusion that AMOFHFCs with acceptable hydrophobic nature are best suited for light weight automotive and structural applications. [ABSTRACT FROM AUTHOR]

This research investigates the dielectric properties of nano epoxy composites by incorporating various concentrations of MoS2 into epoxy resin. The study explores the impact of synthesized nanoparticles on undoped epoxy composites, specifically focusing on their potential applications in dielectric materials. The experimental synthesis and characterization of nanoepoxy composites typically involve time-consuming and expensive methods. This study compares five machine learning (ML) models—random forests, decision trees, extra trees, XGBoost, and gradient boosting—in order to predict the frequency-dependent dielectric constants in these composites under different nanofiller variations in order to address this challenge. To ensure robust model performance, training is carried out on different subsets of the dataset, ranging from 60% to 30%, while the remaining portions are reserved for testing purposes (40% to 70%). The main objective of the study is to assess the performance of each regressor technique using metrics such as adjusted R2 score, MSE, RMSE, and MAE, in which the ET regressor excels. The ET method demonstrates exceptional performance, achieving an adjusted R2 value of 0.9977 and 0.9912 for target variables ε′ and ε′′, respectively when tested with a size of 0.4. The findings underscore the potential of ML models for precise and efficient prediction of frequency-dependent dielectric constants of nanoepoxy composites with various concentrations of nanofillers, offering an alternative to time-consuming and expensive laboratory work.

The paper describes the results of an experimental study of a polyurethane material treated by ion implantation technology. The problems of crack growth in the near-surface layer carbonized by ion treatment were investigated using digital optical microscopy. The methods of atomic force microscopy allowed studying the possibility of carbonized layers delamination from the substrate. As a result, the technology for the production of a multilayer polyurethane material with nanofillers (nanotubes, nanodiamonds, fullerenes, graphenes) and its optimal modification by ion implantation treatment was developed, which makes it possible to improve the biocompatibility of polyurethane implants with human tissues

Bismuth ferrite (BiFeO3, BFO) is one of the few single-phase crystalline compounds exhibiting strong multiferroic properties at room temperature, which makes it promising for use in various fields of science and technology. The remarkable characteristics of BFO at the nanoscale position it as a compelling candidate for enhancing the functionalities of polymeric nanocomposite materials. In this study, we explore the fabrication of polyvinylidene fluoride (PVDF) nanocomposites with a variable content of BFO nanopowders (0, 5, 10, 15, 20, and 25 wt%) by solution casting in the form of thin films with the thickness of ~60 µm. Our findings reveal that the presence of BFO nanoparticles slightly facilitates the formation of β- and γ-phases of PVDF, known for their enhanced piezoelectric properties, thereby potentially expanding the utility of PVDF-based materials in sensors, actuators, and energy harvesting devices. On the other hand, the increase in filler concentration leads to enlarged spherulite diameter and porosity of PVDF, as well as an increase in filler content above 20 wt% resulting in a decrease in the degree of crystallinity. The structural changes in the surface were found to increase the hydrophobicity of the nanocomposite surface. Magnetometry indicates that the magnetic properties of nanocomposite are influenced by the BFO nanoparticle content with the saturation magnetization at ~295 K ranging from ~0.08 emu/g to ~0.8 emu/g for samples with the lowest and higher BFO content, respectively.

Statement of problem Various studies are present to increase the strength and surface hardness of heat polymerized acrylic resin by addition of material or surface treatments. The present study to evaluate an effect of silica nanoparticles on flexural strength and surface hardness of heat polymerized acrylic resin. Purpose The purpose of this study was effect of silica nanoparticles, incorporated into Polymethyl Methacrylate, on flexural strength and surface hardness. The present study compared the effect of silanated and non silanated silica nanoparticles on the flexural strength and surface hardness of heat polymerized acrylic resin. Material and Methods A total of 270 acrylic bars were fabricated, in two batches of 135 each, for testing flexural strength by universal testing machine and surface hardness determined using a digital micro Vickers hardness tester. The control group and subgroups had a sample size of 15 each with varied concentrations of nanoparticles by weight. The fabricated samples were tested for flexural strength and surface hardness. Results Flexural strength was highest for PMMA (Polymethyl methacrylate) with 0.5% silanated silica nano particles as fillers. In both the groups, the flexural strength decreased with increase in filler concentration. Surface hardness was highest in the PMMA group with non-silanated nano particles as fillers at 5% concentration. In both groups the surface hardness improved with an increase in filler concentration. ANOVA and TUKEY’s HSD test were used. P<0.05 was considered statistically significant. Conclusion Lower concentrations of surface-treated silica nanoparticles should be used as fillers to enhance the flexural strength of commercially available heat polymerized acrylic resin. [ABSTRACT FROM AUTHOR]

Metals (Ms) and metal oxides (MOs) possess a strong tendency to coordinate and combine with organic polymers to form respective metal–polymer frameworks (MPFs) and metal oxide polymer frameworks (MOPFs). MPFs and MOPFs can be regarded as composites of organic polymers. MPFs and MOPFs are widely used for industrial and biological applications including as anticorrosive materials in the aqueous phase as well as in the coating conditions. The presence of the Ms and MOs in the polymer coatings improves the corrosion inhibition potential of MPFs and MOPFs by improving their self-healing properties. The Ms and MOs fill the micropores and cracks through which corrosive species such as water, oxygen, and corrosive ions and salts can diffuse and destroy the coating structures. Therefore, the Ms and MOs enhance the durability as well as the effectiveness of the polymer coatings. The present review article is intended to describe the corrosion inhibition potential of some MPFs and MOPFs of some most frequently utilized transition metal elements such as Ti, Si, Zn, Ce, Ag, and Au. The mechanism of corrosion inhibition of MPFs and MOPFs is also described in the presence and absence of metal and metal oxides. [ABSTRACT FROM AUTHOR]

Recently, functional nanomaterials with unique sizes, shapes, and surface chemistry have been fabricated for various applications in all facets of science and technology. Among these diverse nanomaterials, copper oxide nanoparticles (CuO NPs) have garnered considerable attention due to their unique physicochemical parameters and semiconductor properties. Doping various functional materials in CuO NPs and the fabrication of CuO nanofillers functionalized with natural or synthetic moieties delivers improved antibacterial efficacy in food packaging applications. Moreover, the bactericidal effect of modified CuO NPs against foodborne pathogens largely contributes to their usage in food packaging technology. Therefore, it is essential to fabricate effective antimicrobial CuO nanofillers with minimal or no adverse side effects. This review discusses the synthesis, characterization, surface modification, antibacterial properties, food packaging applications, and toxicological implications of the diverse CuO nanofillers integrated in films and composites. In addition, it highlights their adverse side effects and ways to combat adverse situations. The forthcoming generation is expected to lead a groundbreaking surge of inventive food packaging systems (FPS) based on CuO hybrid nanofillers in food packaging industries. [ABSTRACT FROM AUTHOR]

Polyurethane (PU) coatings are widely used in various industries due to their excellent mechanical strength, along with abrasion, chemical and weather resistance. Recently, use of dynamic bonds to increase the recyclability and self-healing properties of PU is being extensively explored. Incorporation of nanofillers into the PU matrix can further enhance their performance as a coating matrix for application demanding thermal stability, mechanical strength, abrasion resistance, corrosion resistance, foul resistance, smudge resistance and UV resistance. It has been reported that inclusion of nanofillers, like nano-silica, graphene, organoclay, zinc oxide and titanium dioxide can provide enhanced functionalities to the PU matrix owing to their small size and high surface area-to-volume ratio to design tailor made PU coatings with desired properties. This review highlights the classification of PUs based on different dynamic chemistry for imparting self-healing and recyclability properties to the polymer matrix. Further, it will also provide a detailed insight regarding various polyol sources used for the synthesis of PUs, technologies adopted to incorporate nanofillers into the PU matrix for developing PU nanocomposite for coating applications and properties associated with these coatings. A brief conclusion highlighting the present challenges and future prospects of the PU nanocomposite coatings is also presented. [ABSTRACT FROM AUTHOR]

Background: The well‐aligned proton exchange membrane (PEM) developed through magnetic field treatment has had a significant impact on the chemistry community related to fuel cell technologies. This is because it possesses advanced proton transport properties that can be efficiently utilized in energy storage devices. The aligned membrane boasts exceptional proton conductivity and power density, particularly in hydrogen‐oxygen fuel cell applications, due to its short proton conduction path, low dependency on humidity, and high barrier to gas permeability. These characteristics can enhance the performance of the aligned PEM. Methods: This review outlines various methods for fabricating aligned membranes using a magnetic field. It summarizes the previous and current research and development aimed at improving the properties of the aligned PEM for fuel cell applications. Significant Findings: Several research gaps and challenges in enhancing the performance of magnetic field‐aligned PEM have been identified in this review, suggesting promising avenues for future research. [ABSTRACT FROM AUTHOR]

This paper presents the investigating results of the effect of different nanofillers like unmodified and modified halloysite nanotubes (HNT), nanosilica, and nano-titanium on the mechanical and thermal properties of polyetherimide (PEI)/silicone rubber-based nanocomposites. The PEI/silicone rubber nanocomposites reinforced with different nanofillers at 3 phr were prepared with the aid of a co-rotating twin-screw extruder. The developed nanocomposites were compared by various mechanical properties, thermal properties, and dynamic mechanical analyses. Morphological properties have been visualized by scanning electron microscope. The results obtained depict that the tensile strength, tensile modulus, storage modulus, and glass transition temperature have significantly increased with the incorporation of modified HNT at 3 phr loading due to the interfacial and inter-tubular interactions between HNT and polymer matrices. The enhancement in glass transition temperature may be because of the restricted movement of the polymer chains by the nanofillers, and the formation of HNT zig-zag structures is the main reason for the improvement of various properties. The bridging effect of modified nanosilica at the blend interface may also be responsible for the enhancement of elongation at break and impact strength which is higher than other nanofillers. [ABSTRACT FROM AUTHOR]

This comprehensive review explores the multifaceted world of natural fiber applications within the domain of composite materials. Natural fibers are meticulously examined in detail, considering their diverse origins, which encompass plant-derived fibers (cellulose-based), animal-derived fibers (protein-based), and even mineral-derived variations. This review conducts a profound analysis, not only scrutinizing their chemical compositions, intricate structures, and inherent physical properties but also highlighting their wide-ranging applications across various industries. The investigation extends to composites utilizing mineral or polymer matrices, delving into their synergistic interplay and the resulting material properties. Furthermore, this review does not limit itself to the intrinsic attributes of natural fibers but ventures into the realm of innovative enhancements. The exploration encompasses the augmentation of composites through the integration of natural fibers, including the incorporation of nano-fillers, offering a compelling avenue for further research and technological development. In conclusion, this review synthesizes a comprehensive understanding of the pivotal role of natural fibers in the realm of composite materials. It brings together insights from their diverse origins, intrinsic properties, and practical applications across sectors. As the final curtain is drawn, the discourse transcends the present to outline the trajectories of future work in the dynamic arena of natural fiber composites, shedding light on emerging trends that promise to shape the course of scientific and industrial advancements. [ABSTRACT FROM AUTHOR]