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An environmental pollution problem is caused in part by packaging materials made from non-biodegradable synthetic polymers derived from petroleum. In this study, eco-friendly biofoams derived from natural rubber (NR) latex and rice starch (RS) were manufactured on a laboratory scale using the Dunlop process. Rice starch content was varied from 0 to 50 phr. The morphological, thermal, physical, mechanical, and biodegradability properties of the NR/RS biocomposite foams were characterized. Scanning electron microscopy (SEM) was used to assess the morphology of the foam cells. Dynamic mechanical thermal analysis (DMTA) and Thermogravimetric analysis (TGA) were used to investigate the thermal characteristics. When RS was present, it was discovered that the biocomposite foams had decreased thermal stability and enhanced biodegradability. Introducing RS into the NR/RS biocomposite foams also decreased tensile strength, elongation at break, and rebound resilience but increased the 100% modulus, hardness, compression force deflection (CFD), and compression set. The NR/RS biocomposite foams better preserved the banana fruit than the absence of foam, with lower ethylene accumulation, lower total soluble solids (TSS), higher pulp firmness, and good color preservation. This demonstrated that these NR/RS biocomposite foams helped to preserve banana fruit quality during storage and could be used in sustainable packaging applications. [ABSTRACT FROM AUTHOR]

Thermoplastic starch (TPS)/cellulose nanocrystal (CNC) films with glycerol or sorbitol plasticizers at 30 and 40% concentrations were prepared by casting over the whole composition range. The nanocrystalline cellulose was extracted from bleached flax by sulphuric acid hydrolysis. The haziness, tensile strength, thermal stability, and the effect of storage on crystal structure were investigated. Water vapor sorption of the neat TPS and flax-CNC films and water vapor permeability of the composites were measured at various humidity differences. The results showed that the high aggregation tendency of flax-CNCs significantly increases the opacity of films regardless of the type and amount of plasticizer. The reinforcing effect of nanocrystals can only be exploited at small concentrations (0–5%). However, 3–4% flax-CNCs result in a 15–25% reduction in water vapor permeability. Retrogradation of the TPS also reduced without changing the thermal stability. The properties of composites and their compositional dependence differ significantly from those of the composites prepared previously with cotton-CNC. Thus, knowledge of the properties of CNCs is essential for explaining the properties of polymer/CNC composites and the compositional dependence of properties. [ABSTRACT FROM AUTHOR]

The drastic increase in the amount of packaging waste from conventional plastics, caused by improper waste management, is a serious challenge for the planet. It is therefore worth considering how we can solve this problem. Thus, it is necessary to develop new polymeric materials that retain the functional properties of traditional plastics but are susceptible to degradation with the participation of microorganisms. The development of new eco-friendly materials requires a holistic approach in terms of their disposal. Organic recycling enables the disposal of biodegradable packaging along with food remains that are difficult to remove. The article presents a study on the degradation of biocomposites of polylactide with cork in various environments (water, buffer, and compost). The obtained results indicate a clear influence of the presence of the filler and its amount on the degradation profile of the composites. In addition, the effect of sample shrinkage was observed, especially during degradation in water, where the pH decreases during the process due to the appearance of degradation products. This effect may be important not only for the degradation profile of the packaging but also during its use. Packaging distorted due to shrinkage may be a sign of improper product storage. [ABSTRACT FROM AUTHOR]

Seaweed from macroalgae and cellulose from nonwood materials have gained attention in various fields. This study explores how seaweed and cellulose nanofibers (CNF) interact to form 3D networks in composite bioaerogels. The ratio of CNF and seaweed was varied to see how it affects the aerogel's inside and its properties. The observations show that the biocomposite aerogel is more rigid and shrinks less than using a single biopolymer. The CNF aerogel has a fine, thin network structure, and the seaweed aerogel has a thin sheet structure. The biocomposite aerogel combines both a fine network and a thin sheet structure. The composite aerogel's mechanical properties are significantly influenced by seaweed composition. The introduction of CNF increases elasticity, while seaweed enhances firmness. Generated computer modelling revealed that the abundant hydroxyl groups in CNF facilitated the formation of intermolecular bonds with seaweed. The bonding led to increased adhesion and entanglement between biopolymers, consequently enhancing elasticity and establishing a stable intermolecular interaction. The 3D X-ray imaging model shows that the skeletal framework primarily consists of seaweed biopolymer, with CNF serving to reinforce this structure thus enhancing the mechanical properties and robustness of the composite bioaerogels. [ABSTRACT FROM AUTHOR]

Sago starch (SS) was blended with natural rubber (NR) using nanoclays, namely montmorillonite (MMT), kaolinite (KAO), and kaolinite modified by dimethyl sulfoxide (KAO-D) to enhance its physical and mechanical properties. Each nanoclay was incorporated at 2, 4, 6, and 8 wt%, respectively. The SS80NR20 (80 wt% of sago starch and 20 wt% of natural rubber) biocomposites were characterized by solubility of water, water vapor transmission, mechanical and thermal properties. The constituent interaction and morphology of the SS80NR20 biocomposites were also presented by using X-ray diffraction (XRD) technique and scanning electron microscope (SEM). The findings demonstrated that the inclusion of clays significantly improved both the water resistance and tensile properties when compared to the SS80NR20 blend. In the SS80NR20 biocomposites, MMT at 6 wt% exhibited the lowest moisture content, solubility in water, and water vapor transmission. As the amount of nanoclay in the biocomposites increased, their tensile strength dramatically increased whilst their strain at break had a tendency to diminish. Strong interaction by establishing the intercalated structure of MMT, and KAO within SS80NR20 biocomposites were attributed to both physical and mechanical properties, while the weak interaction at the interface of SS and NR was attributed to KAO-D. [ABSTRACT FROM AUTHOR]

The protein from black soldier fly larvae was used as a functional ingredient of a novel green nanofiber. Larvae protein powder (LP) was blended with biodegradable poly(e-caprolactone) (PCL) and processed in an electrospinning machine using a coaxial feeding/mixing method to produce nanofibers approximately 100-350 nm in diameter. To improve the dispersion and interface bonding of various PCL/LP nanofiber components, a homemade compatibilizer, maleic anhydridegrafted poly(e-caprolactone) (MPCL), was added to form MPCL/LP nanofibers. The structure, morphology, mechanical properties, water absorption, cytocompatibility, wound healing, and biodegradability of PCL/LP and MPCL/LP nanofiber mats were investigated. The results showed enhanced adhesion in the MPCL/LP nanofiber mats compared to PCL/LP nanofiber mats; additionally, the MPCL/LP nanofibers exhibited increases of approximately 0.7-2.2 MPa in breaking strength and 9.0-22.8 MPa in Young's modulus. Decomposition tests using a simulated body fluid revealed that the addition of LP enhanced the decomposition rate of both PCL/LP and MPCL/LP nanofiber mats and in vitro protein release. Cell proliferation and migration analysis indicated that PCL, MPCL, and their composites were biocompatible for fibroblast (FB) growth. Biodegradability was tested in a 30 day soil test. When the LP content was 20 wt%, the degradation rate exceeded 50%. [ABSTRACT FROM AUTHOR]

The augmented demand for sustainable nanocomposites has paved the way to explore naturally derived materials. Nanocellulose, with its bountiful sources and inherent properties, ranks top in the list of biofillers with a perspective of reducing the carbon footprint. A systematic study is required to understand the reinforcing effect of various types of nanocellulose. In the present work, we selected three types of nanocellulose, i.e., cellulose nanocrystal (CNC), cellulose nanofiber (CNF) and microfibrillated cellulose (MFC), to investigate the effect of geometrical structure on the properties of unvulcanized natural rubber (NR). Incorporating these fillers improved the tensile strength and modulus of natural rubber films significantly through reinforcement via filler network structure. The reinforcing effect of CNF was found to be higher compared to CNC and MFC, where an increase of 3.85 MPa in tensile strength from the neat sample was obtained. More uniform dispersion was evident through transmission electron microscopy, atomic force microscopy and Raman imaging for CNF in the rubber matrix. The structural properties were determined using Raman spectra and X-ray diffraction. The rheological studies revealed a good interaction between filler and NR. The work presented comprehensively compares different types of nanocellulose as reinforcing filler in NR matrix, which will help the researchers select an ideal type for their specific application and, thus, the proper usage of renewable resources, leading to sustainability and a circular economy. [ABSTRACT FROM AUTHOR]

Arsenic, an element found in the Earth’s mantle, can be highly toxic, especially in its As(III) form. It enters our food chain through human activities like melting metals, using arsenic-based pesticides, and natural processes like volcanoes and rock breakdown. Consuming too much arsenic is extremely dangerous, impacting many countries worldwide. To tackle this issue, various methods like filtering, adding chemicals, and using electricity have been developed to clean arsenic-contaminated water. Among these, adsorption is a standout approach due to its simplicity and effectiveness. Biopolymers from living sources offer a natural solution, easily tweaked for arsenic removal. These biopolymers contain functionalities that can strongly latch onto toxic materials, acting like magnets. By customizing them with compounds like titanium dioxide (TiO2), magnetite (Fe3O4), and others, they become even better at capturing arsenic, shaped into tiny particles or beads. This adaptation makes biopolymers a promising choice for cleaning arsenic from water. This review focuses on ways to clean water, specifically exploring how materials like chitosan, alginate, and modified cellulose can be used to remove arsenic by adsorption. It investigates how these materials work under different conditions, highlighting important details. By sharing these insights, this article contributes to the ongoing efforts to ensure cleaner water resources. [ABSTRACT FROM AUTHOR]

In the global pursuit of using sustainable constituents for developing composite materials, the current investigation has paid particular attention to the most promising biopolymers, such as poly(lactic acid) (PLA) and bio-based poly(butylene succinate) (bio PBS). The research endeavor emphasizes a comparative assessment of short sisal fiber (SF) reinforced (10, 20, and 30 wt%) PLA and bio PBS biocomposites. The analysis and discussion have been reported for the thermal, mechanical, crystallinity, and dynamic mechanical behavior of developed composite materials. Based on mechanical properties, the optimal fiber loading for SF/PLA and SF/bio PBS biocomposites was 20 and 30 wt%, respectively. The developed composites have shown a considerable improvement in crystallinity of 17.88 and 41.13% at 20 and 30 wt% of fiber loading in SF/PLA and SF/bio PBS, respectively. The maximum storage modulus values of 14.23 GPa (20SF/PLA) and 11.74 GPa (30SF/bio PBS) were observed. The loss modulus of the SF/PLA and SF/bio PBS composites was around 74 and 89% higher than the loss modulus of the PLA and the bio PBS matrix, respectively. Overall, composites fabricated with bio PBS (SF/bio PBS) have shown better crystallinity, thermal stability, and ease of processing than SF/PLA composites. [ABSTRACT FROM AUTHOR]

The present work reports on the development of environmentally friendly, completely biodegradable wood plastic composites based on polylactide (PLA) and tangerine peel flour (TPF), plasticized by α-terpinyl acetate (TA). The TPF varied in the 10--30 wt% while the PLA to TA (wt%/wt%) was set to 4 (i.e., 25 wt% TA plasticizer was added with regard to the PLA wt%). The developed composites were processed by extrusion and injection molding. The composites presented excellent elongation at break, achieving values of 300% for the PLA+TA sample. Elongation at break values of 200% for the PLA composite with 10 wt% TPF and plasticized with TA were obtained. Those results were confirmed by the appearance of filament-like structures observed in field emission scanning electron microscopy images. Differential scanning calorimetry and dynamic mechanical thermal analysis revealed a remarkable decrease in the glass transition temperature of PLA as a result of the plasticizing effect of TA. Glass transition was reduced from 63°C down to 41°C approximately. This implied an increase in the ductility of the material. The samples with TPF exhibited a dark brown color, making them perfect for wood plastic composite applications. Water contact angle results show that TA and TPF change the wetting properties of the obtained composites. A general decrease in the water contact angle was observed with the addition of TPF and TA. Finally, disintegration tests proved that the developed composites are fully biodegradable. All the samples except for neat PLA achieved 100% disintegration in controlled compost soil conditions after 5 weeks, while neat PLA reached complete disintegration in 6 weeks. [ABSTRACT FROM AUTHOR]

Public health concerns caused by heavy metals present in wastewater have come to global attention. Heavy metal contamination of water resources will have a negative impact on marine species, the environment, and the ecosystem. A va- riety of wastewater treatment methods have been developed and improvised throughout the decades to counter this issue. Among the wastewater treatment methods, the adsorption method is believed to have a high potential and is suitable for re- moving heavy metals from wastewater. This review focuses on selecting various types of crosslinked polymer nanocom- posites (CPN) as having a significant role in the removal of heavy metals from wastewater via the adsorption method. The adsorption capacity of the CPN was influenced by the polymer types, nanofiller selection, synthesis methods, and exposure conditions. This article will give us important information to improve the functionality of CPN as an adsorbent in wastewater treatment. The challenge, SWOT (strengths, weaknesses, opportunities, and threats) analysis, and future aspects of the CPN are shared in this review. [ABSTRACT FROM AUTHOR]

A biomimetic strategy was adopted by incorporating nano-fluorcanasite (nFC) within biocompatible and biodegradable poly-(ε-caprolactone) (PCL) matrix to obtain functionally tuned bio-nanocomposite bone scaffolds. A hybrid approach was adopted using fused deposition modelling, solvent casting and thermally induced phase separation to develop the scaffolds. Phase evolution study through X-ray diffraction revealed dominant crystalline phases (fluorcanasite and fluorapatite) and enhanced crystallinity of the scaffolds. Microstructural investigation through field emission-scanning electron microscopy revealed interconnected gradient porosities and hierarchical (meso, micro and macro) porous architecture within the scaffolds similar to natural bone. The elemental mapping study further confirmed higher calcium:phosphate (Ca:P) ratio upon nFC incorporation, desirable for bone repair. The volume visualisation through X-ray micro-computed tomography confirmed the presence of porous micro-architecture and homogenous dispersion of nFC particulates within the scaffolds. Mechanical performance of the bio-nanocomposite scaffolds was also found to be enhanced to sustain the load against pore collapse. Enhanced cell viability and cellular proliferation response with human osteosarcoma bone cells established the in-vitro biocompatibility of the scaffolds. Finally, this study opens up a unique pathway in the fabrication of biomimetic bone scaffolds with a highly conducive cellular environment. [ABSTRACT FROM AUTHOR]

In this study, silicon-doped hydroxyapatite (SiHAP) nanoparticles and poly(hydroxybutyrate-co-3-hydroxyvalerate, PHBV) were used to develop biodegradable ‘green’ composites due to their intrinsic biodegradability and biocompatibility properties. The novel bionanocomposites were prepared by melt compounding with 0.5, 2, and 3 wt% of SiHAP content. The fracture surface of the bionanocomposites samples from scanning electron microscopy (SEM) exhibited good dispersion of SiHAP in the PHBV matrix at 0.5 wt%. X-ray diffraction (XRD) measurements showed an enhancement of the crystallinity of the PHBV matrix, thereby acting as a nucleating agent, increasing polymer crystallinity from 50 to up to 73% at 3 wt% loadings. Dynamic mechanical analysis (DMA) was used to measure the composite and neat samples’storage modulus, loss modulus, and damping factor under an oscillating load. DMA analysis showed an increase in storage modulus of 80% at 20°C and 0.5 wt% SiHAP loadings. Thermal gravimetric analysis (TGA) results showed that the thermal stability of PHBV is slightly decreased by adding 2 and 3 wt% SiHAP. 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) Assay and 4′,6-diamidine-2′-phenylindole dihydrochloride (DAPI) staining experiments have demonstrated that PHBV/SiHAP composites exhibit good in vitro bioactivity due to the silicon-doped hydroxyapatite nanoparticles. It is con)cluded that the addition of SiHAP can be a viable strategy for obtaining novel bioactive and biodegradable nanocomposites with improved mechanical and biological properties for potential medical application. [ABSTRACT FROM AUTHOR]

Biodegradable plastics such as poly(lactic acid) (PLA) are gaining considerable interest as promising substitutes for conventional petroleum-based plastics due to ecological, health, and environmental concerns. PLA possesses good biodegradability and biocompatibility but is limited by its slow crystallization rate, low impact resistance, and high costs. In this study, a small amount of natural wood fiber (WF) was incorporated into PLA to improve mechanical and crystallization properties as well as cost reduction. The effects of WF size (20–40, 80–100, and 140–160 mesh) and loading content (0.5– 8 wt%) on the mechanical and crystallization properties were investigated and compared. Results indicated that WF of 80– 100 mesh (WF80-100) exhibited a better reinforcement effect on PLA than the other two sizes of WF. The optimal loading content for WF80-100 was 1 wt%, at which the flexural and tensile strength increased by about 18% compared to neat PLA, and the elongation at break increased by 27%. Moreover, the degree of crystallinity and crystallization rate significantly in)creased with the addition of WF80-100. Polarized optical microscopy observation revealed that the number of spherulites in)creased in 1WF80-100/PLA composite and the spherulite size decreased compared to neat PLA. These findings confirmed that WF, even at a low addition level, could act as both a reinforcement material and an efficient nucleating agent for PLA, which is closely related to its size. [ABSTRACT FROM AUTHOR]

Fused deposition modeling (FDM) is a versatile additive manufacturing technique for producing polymeric parts. Incorporating a foaming agent into the filament material enables the FDM-printing of thermoplastic foams, which opens up new possibilities for achieving desired mechanical property combinations. This study explored the process-property design space of FDM-printed polylactic acid (PLA) foams. Tensile and compression specimens were produced at a wide range of printing parameters using a commercial thermoplastic filament containing a foaming agent. Increasing the nozzle temperature and decreasing the filament feed rate increased the extent of foaming. Adjustment of the nozzle temperature, feed rate, and infill ratio controlled porosity over a density range of 0.24 to 1.17 g/cm³. Tuning of the mechanical properties over an order of magnitude was demonstrated, with elastic moduli ranging from 0.24 to 3.7 GPa and tensile strength ranging from 4.2 to 34.5 MPa. The mechanical behavior closely followed the Gibson-Ashby model predictions. Foaming filaments provide a new tool for tuning the mechanical response of FDM-printed parts to achieve unique combinations of mechanical properties that are not attainable through conventional methods. [ABSTRACT FROM AUTHOR]

The aromatic biopolymer lignin, present in lignocellulosic material, can act as an antioxidant and has antimicrobial and UV blocking properties due to the presence of aromatic ring and phenolic hydroxyl groups with aliphatic hydroxyl, carboxyl, methoxy groups. It is produced in huge amounts as a by-product during the delignification process in the paper and pulp industries. Lignin-based polymer composites with advantageous properties can fulfill the growing demand for lightweight polymer composites. Incorporating lignin as reinforcement in polymer composite can make it more environmentally friendly. Among four technical lignin, kraft lignin and lignosulfonate have a unique molecular structure that includes sulfur and can be extracted from black liquor and spent liquor, respectively. Moreover, the negatively charged sulfite groups in lignosulfonate can have an electrostatic attraction to a wide range of positively charged polymers and materials, making it an ideal additive for the adsorbent material. The main intention of this review is to increase the knowledge on the use of cheap and widely available kraft lignin and lignosulfonate as reinforcement in polymer composites and to find the shortcomings to advance further research on the application of technical lignin. The article mainly focuses on advancements in kraft lignin and lignosulfonate polymer composites. [ABSTRACT FROM AUTHOR]

The development of biodegradable and biocompatible materials to replace non-biodegradable synthetic polymers has received significant interest in biomedical applications. Amongst all biopolymers, polybutylene succinate (PBS) possesses excellent properties, such as biocompatibility, easy processability, biodegradability, non-toxic, good mechanical and thermal properties, which makes it a suitable candidate to replace non-biodegradable synthetic polymers in biomedical applications. This review provides recent advancements, trends, and challenges for the utilization of polybutylene succinate (PBS) and PBS-based materials for biomedical applications, viz. drug delivery, tissue engineering, and biomedical devices. In addition, the design of medical devices from PBS using 3D and 4D printing is also presented. The market analysis, comparison of virgin PBS and synthetic polymer properties, as well as the end of service life, are summarized briefly. The current status, challenges, and future directions are also discussed. [ABSTRACT FROM AUTHOR]

Herein, we report interphase percolation phenomena in chitosan-graphene oxide (CS-GO) nanocomposites as a function of water content. The dependencies of the DC conductivity and the static dielectric constant have been investigated in a wide range of GO concentrations (0-12 wt%) and water contents (0, 4, 9, and 24%). Fourier-transform infrared spectroscopy (FTIR), Raman spectroscopy and X-ray diffraction (XRD) measurements reveal the presence of strong interaction between the CS matrix and GO fillers. For annealed CS-GO films in a vacuum (no water content), the DC conductivity and dielectric constant do not depend upon the GO concentration. When the water content increases, a percolation phenomenon is now detected; by increasing water content, the percolation threshold shifts to a lower GO concentration. A three-phase model which includes the conductivities of CS and GO, and an interphase layer fits well DC conductivity data; this model based analysis suggests that upon increasing the water content, the conductivity of the interphase layer is higher than the one of both neat CS and GO. Water molecules at the interface drive a high-conductivity interfacial shell supporting a proton transfer mechanism; this mechanism is a plausible scenario for percolation in wet CS-GO nanocomposites. Our results may be of great importance in the applications of such nanocomposites in flexible electronics, biomedicine, proton exchange membranes, and sensors. [ABSTRACT FROM AUTHOR]

Polylactic acid (PLA) has shown two different crystalline structures, namely a and a' when cooled down from the melt state. However, a-PLA has shown significant improvement in the barrier and mechanical properties of PLA. Although the effect of some nucleating agents on phase transformation of the PLA has been determined in the past, this is the first attempt, the effect of the starch nanocrystals on the formation of polymorphic crystal structure of PLA was evaluated. In this framework, the effect of lactic acid grafted starch nanocrystals (SNCs-g-LA) concentrations on the phase transition, and crystallization behavior of PLA/SNCs-g-LA nanocomposites at different isothermal crystallization temperatures (Tc) were studied. The results indicate that SNCs-g-LA nanoparticles promote the degree of crystalline transition to yield the highly crystalline ordered a-PLA. Further, the half-time crystallization (t1/2) of PLA composites was calculated by the Avrami equation. The t1/2 of PLA was minimum by adding 5 wt% SNCs-g-LA nanoparticles, and it decreased from 10.4 to 3.9 min. The growth rate of the spherulite morphology of PLA composites showed a significant improvement in the crystalline structure of PLA/SNCs-g-LA (5 wt%) nanocomposites as well. Finally, small angle X-ray scatting (SAXS) analysis showed that the inclusion of 5 wt% grafted SNCs resulted in the increment of the long period (Lac) as well as crystal layer thickness (Lc). [ABSTRACT FROM AUTHOR]

Nowadays, there has been an increase in demand for using biodegradable food packaging due to its sustainable and environmentally friendly. Poly(lactic acid) is an interesting alternative. To increase the potential use of packaging, the development of a bioactive packaging by using a natural antimicrobial like chitosan has gained considerable attention due to its excellent antimicrobial activity and performance meanwhile, both layers have different surface properties that result in poor interfacial adhesion. So, this research aims to improve the interfacial adhesion between PLA and chitosan by grafting chitosan with 3-(trimethoxysilyl)propyl methacrylate (TMSPM) using ultrasonic vibration and to study the preparation of the laminated film via lamination technique. From the FTIR results, the characteristic peaks at a wavenumber of 1701 and 877 cm-1 corresponding to the C=O vibration in the methacrylate and Si-O stretching groups of TMSPM were observed. This indicates that the grafting reaction occurs completely. Interestingly, the PLA/CS_10%TMSPM laminated film revealed an improved interfacial adhesion and hydrophobicity. This was observed from the strength value that increased from 21.9 to 35.8 MPa and the water vapor permeability value that decreased from 14.6·10-7 to 9.1·10-7 (g·m)/(m2·Pa·s) when compared to the PLA/CS laminated film. In addition, the PLA/CS_10%TMSPM laminated film also showed excellent antimicrobial activity against E. coli as well. [ABSTRACT FROM AUTHOR]

Energy and environmental protection are two major problems that are faced by the current generation. Coal has been utilized traditionally as a source of electricity globally. However, more ash is generated from the combustion of coal which is carried by gases and precipitated into fly ash. The main problem with fly ash is that, if it is not properly disposed it may cause pollution(s) in the water and soil, which in turn disturb ecological cycle and have negative impact on the environment. Based on the above statement(s), more efforts have been done to recycle fly ash or its utilization for advanced applications. One of the preferred methods for recycling fly ash, is to incorporate it in polymer matrices in order to improve the strength of polymer matrices for advanced applications. Fly ash has been utilized as a reinforcing filler for various polymer matrices due to its high strength and low cost. This review paper discusses different fabrication methods for fly ash/polymer matrices composites. The effect of particle size, modification, synergy of fly ash with other fillers reinforced polymer matrices on the mechanical properties are discussed. Furthermore, there is an in-depth discussion about the specific applications of fly ash reinforced with different polymer matrices. There is also a discussion based on the fly ash/fiber/polymer hybrid composites in relation to the preparation method and mechanical properties, since hybrid systems are known for better properties than single fillers. [ABSTRACT FROM AUTHOR]

A glucose sensor has been developed for daily diagnosis due to high level of glucose can cause diabetes. This study purposes of fabricating an electrospun fiber film of poly(3-aminobenzylamine) (PABA)/functionalized multi-walled carbon nanotubes (f-CNTs) composite for use as electrochemical glucose biosensor. The electrospun PABA/f-CNTs composite film was fabricated on a screen-printed electrode and characterized by attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS), and field emission--scanning electron microscopy (FE-SEM). The presence of f-CNTs in the composite could enhance the electrochemical activities of the PABA, which was confirmed by cyclic voltammetry (CV), amperometry, and electrochemical impedance spectroscopy (EIS). The electrochemical glucose biosensor based on the electrospun PABA/f-CNTs composite film showed a sensitivity of 0.40 µA·mm-2·mM-1 with LOD of 0.067 mM in the linear range of 0.56-2.8 mM, high selectivity under the common interferences (i.e., uric acid, ascorbic acid, and dopamine) and good stability up to 1 week with the current response retained about 80%. [ABSTRACT FROM AUTHOR]