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In recent years, shape memory polyurethanes have gained substantial attention and are targeted for a range of smart and functional materials. In this work, the development of nanocrystalline celluloses (CNCs) enabled polycaprolactone-based shape memory polyurethane biocomposite using an in situ one-pot reactions is reported. The incorporation of up to 10 wt. % CNCs resulted in a remarkable enhancement in the tensile strength at yield (from 0.2 MPa to 7.2 MPa), tensile strength at break (167% improvement), and modulus of elasticity (from 3.5 to 139.3 MPa) while maintaining the elongation at break. This was attributed to the simultaneous action of CNCs as a nucleating agent for crystallization and highly compatibilized reinforcing agent of the network. Moreover, the in situ incorporation of CNCs enhanced the shape memory capability of polyurethanes, which enables its employment in functional material applications, such as the biomedical sector. The intimate interfacial adhesion between the CNCs and the polymer matrix, which promoted shape fixating and recovery, was confirmed by fractured surface morphology studies. Rheology characterizations provided strong evidence that the addition of CNCs increased the shape fixity attributed to the stiffness of CNCs below the glass transition temperature (Tg) compared to the neat PU in conjuncture with the higher Tg of CNCs. Overall, the developed polymer nanocomposites are appealing materials for biomedical applications.

In this work, biocomposites based polylactic acid (PLA) filled with piper betle fiber (PBF) were successfully synthesized by solvent cast-film method using chloroform as the solvent. The PBF was treated with 7% NaOH. The biocomposites were loaded separately with untreated and treated PBF at 1 to 3 wt% and investigated for tensile properties and morphological of fractured surfaces. Tensile strength and modulus elasticity of biocomposites were increased with addition of betel particles and found to be higher than the matrix. Furthermore, the alkali treatment of PBF had considerably improved tensile and modulus of biocomposites compared to those of biocomposites with untreated PBF. A contrary trend was found in the case of elongation at break. However, biocomposites with treated PBF had greater elongation compared to those of biocomposites with untreated PBF. These results were identified by fracture examination with scanning electron microscopy (SEM). SEM observations showed the good bonds formed between treated PBF and PLA. This indicated by less cavity and roughness on biocomposite fractured surface with treated PBF.

The lack of the required mechanical strength and adequate biodegradation rate of calcium phosphate materials constitutes the most relevant drawback prohibiting their use for orthopaedic applications. One of the promising strategies to overcome this intrinsic limitation is the functionalization of these materials through the combination with specific functional groups. In this study, we investigated APTES (3-aminopropyl-triethoxy-silane) functionalization of a poorly crystalline apatite (PCA) and its further combination for the first time to chitosan (CS) to elaborate PCA-APTES-CS functionalized composite material. XRD patterns of the elaborated materials exhibit broad peaks typical of poorly crystalline apatite. FTIR spectroscopy showed, in addition to the PCA characteristic bands, bands assigned to silane alkyl groups and evidenced the success of functionalization process. The TGA analysis confirmed the attachment of 8 wt% of APTES and 3 wt% of chitosan within the composite. SEM microscopy and EDX silicon mapping demonstrated a homogeneous silane presence on functionalized apatite surface and showed that chitosan enveloped the functionalized apatite particles surface. The elaborated PCA-APTES-CS functionalized composites exhibited compressive strength similar to the spongy bone. The functionalized biocomposite will be investigated as potential biomaterial for orthopedic application.

This study presents a method for synthesizing hydroxyapatite (HA) with high crystallinity at low temperatures using a small amount of graphene oxide (GO), and the characters of produced GO/crystalline HA complex was investigated. The morphology and components of the synthesized HA (i.e., HA/GO) were analyzed through scanning electron microscopy, X-ray diffraction and transmission electron microscopy; additionally, the yield of the HA/GO was assessed. The HA/GO results were analyzed by comparing them with those obtained using HA synthesized without GO as a control group. A yield of ~4 mg of HA/GO was attained by the use of 100 μg of GO, demonstrating 20% improvement over the control group. The crystal phase analysis confirmed that crystalline HA of fine quality with nano-size was simply synthesized without intermediate phases using adding a small amount of GO, and the synthesized HA without GO is consist of intermediate phases (brushite and octacalcium phosphate) and hydroxyapatite. Biological characteristics of HA/GO were assessed through the behavioral analysis of mesenchymal stem cell attachment, proliferation, differentiation, and its protein adhesion capacity. HA/GO exhibited excellent biocompatibility and osteogenic differentiation behavior together with better protein adhesion ability than HA. These results demonstrate potential of HA/GO for application in bone tissue engineering. Thus, HA/GO can be developed as a biomimic biocomposite by combining it with bioactive molecules such as growth factors.

An optimal performance of bone implants with bioceramic coatings is closely related to the surface modification technology. For the first time, we have evaluated a gas detonation deposition (GDD) approach to obtain biocompatible ceramic coatings based on bioglass (BG) and calcium phosphates on Ti-based alloys as prospective materials towards their application for the development of bone implants. For the production of the coatings, hydroxyapatite (HA), HA metal-substituted (containing Ag+, Cu2+, or Zn2+) and tricalcium phosphate (TCP) were synthesized and characterized. Pure powders and their combination with BG were used to obtain coatings on a Ti–6Al–4V alloy using the developed automatized GDD setup. The microstructure, phase and chemical composition of the produced coatings were studied using XRD, SEM-EDS and Raman spectroscopy. The produced coated materials were evaluated in vivo in Wistar rats to analyze a reparative osteogenesis over a period of 12 weeks. The results regarding the optimization of the GDD method indicate its high productivity, as confirmed by high deposition rates. The highest deposition rate was observed for the coatings obtained from the HA metal-substituted powders. The results revealed a partial transformation of a HA phase to an α-TCP phase during the deposition, with a prevalence of the HA-phase in the coatings. According to the histological evaluation, the reparative osteogenesis occurs through the perimeter of the titanium implants, whereas the regeneration level increases from the 4th to the 12th week. The highest osteointegration level was detected for the implants coated with a biocomposite consisting of BG, HA and TCP. The results of the current study demonstrate an effectiveness of the GDD method to produce biocompatible coatings on Ti-based alloys. This provides excellent prerequisites towards the application and standardization of the GDD technology to manufacture bone implants for bone fixation and defect replacement, as well as the development of dental implants.

Dura mater defect and subsequent cerebrospinal fluid (CSF) leakage usually appear in trauma or neurosurgical procedures and are followed by a series of serious complications and even death. The use of a qualified dura mater substitute with multifunction of leakage blockade, adhesion prevention, and dura reconstruction is one of the promising treatment methods. However, even though some products have been used in the clinic, none of the substitutes achieved the required multifunction. In this study, we aimed to design and fabricate a dura repair composite with the ideal multifunction. By biomimicking the structure and component of natural dura, we applied poly(L-lactic acid) (PLLA), chitosan (CS), gelatin, and acellular small intestinal submucosa (SIS) powders to successfully prepare a triple-layered composite. Then, a series of specific devices and techniques were developed to investigate the performance. The results revealed that satisfactory structural stability could be realized under good synergistic interactions among the components. In addition, all the findings suggested that the bionic triple-layered composite showed satisfactory multifunction of leakage blockade, adhesion prevention, antibacterial property, and dura reconstruction potential, and thus, it might be a promising candidate for dura repair. Statement of significance Developing qualified dura mater substitutes with multifunction of leakage blockade, adhesion prevention, and dura reconstruction is crucial for treating dura mater defect and subsequent cerebrospinal fluid (CSF) leakage that appear in trauma or neurosurgical procedures. In this study, we designed and fabricated a triple-layered dura repair biocomposite with satisfactory structural stability and desired multifunction based on biomimicking of the structure and component of natural dura. Moreover, a series of specific devices and techniques were developed to investigate the relevant performance. Overall, the developed hydrogel electrospinning system exhibited excellent advantages in achieving multifunction and could be applied widely in the future to achieve multifunctional tissue repair materials.

The study of the impact energy and the composite behaviour plays a vital role in the efficient design of composite structures. Among the various categories of impact tests, it is essential to study low-velocity impact tests as the damage generated due to these loads is often not visible to the naked eye. The internal damages can reduce the strength of the composites and hence the impact behaviour must be addressed specifically for improving their applications in the transport industry. The main aim of this paper is to provide a comprehensive review of the work focusing on the assessment of biocomposites performance under low impact velocity, the different deformations, and damage mechanisms, as well the methods to improve the impact resistance.

In modern decades, an increase in environmental awareness has attracted the keen interest of researchers to investigate eco-sustainable, recyclable materials to minimize reliance on petroleum-based polymeric compounds. Poly (3-hydroxybutyrate) is amorphous, linear, and biodegradable bacterial polyesters that belong to the polyhydroxyalkanoates family with enormous applications in many fields. The present review provides comprehensive information on polyhydroxybutyrate production from different biomass feedstock. Various studies on PHB production by genetically engineered bacterial cells and optimization of parameters have been discussed. Recent technological innovation in processing polyhydroxybutyrate-based biocomposite through the different process has also been examined. Besides this, the potential applications of the derived competent biocomposites in the other fields have been depicted.

Raising environmental awareness had forced researchers to explore the potential and implementation of environmentally friendly materials as alternatives for conventional materials. Environmentally friendly materials are biodegradable, safer, non-toxic, lightweight, cheap, and readily available. Arrowroot starch has a high content of amylose (~35.20%) which makes it suitable for better film production. Starch extracted from arrowroot rhizomes can be blended, plasticized with other polymers, or reinforced with fibres to improve their properties. The melt blended glycidyl methacrylate-grafted polylactide (PLA-g-GMA) and treated arrowroot fiber (TAF) treated with coupling agent developed PLA-g-GMA/TAF composite, which showed better properties than the PLA/AF composite. To the best of our knowledge, no comprehensive review paper was published on arrowroot fibres, starch biopolymer, and its biocomposites before. The present review focuses on recent works related to the properties of arrowroot fibres and starch, and their fabrication as biocomposites. The review also reveals the vast potential of arrowroot fibres and starch for food industries, medicines, textiles, biofuel, pulp, and paper-making industries, bioenergy, packaging, automotive, and many more.

This study investigated the optimal use of industrial hemp fibers for polylactide (PLA) biocomposite and linear low density polyethylene (LLDPE) composite reinforcement. In these samples both low-grade fiber, waste and high-quality hemp fiber are used. To optimize the use of hemp fiber in both the biocomposite and the fossil-based polymer matrix composite, the first phase of the technology envisages the use of high-quality hemp fibers in the production of the PLA biocomposite. This process also produces a by-product (hemp waste). Further, in the second stage, the technology envisages the use of hemp waste in the production of LLDPE (semi-fossil) composite. PLA and hemp fiber biocomposites have high mechanical properties, which allow reducing the amount of materials in the product. Also, low-grade fiber composites show remarkable mechanical properties. The advantage of extracting hemp fibers is that it is possible to use all parts of the plant at the same time for the production of different products – hemp seeds, their shells, hemp shives, thus maximizing the value added of this resource, that conforms to the concept of sustainable development and circular economy principles. Also, it improves the ecological assessment (Life Cycle Assessment) of the product and reduces the environmental impact. Annually renewable hemp fiber resource has the potential to create new products and develop the renewable material industry in EU. Considering the Europe Green Deal guidelines [1], it is important for the manufacturer to provide a sustainable, economically justified and environmentally friendly material (switch to recyclable materials till 2021, switch to recycled, reusable or alternative materials till 2025).

In the present paper, we describe how a robust and fundamental methodology was developed for extraction and determination of a principal natural toxin compound, simplexin, from a series of bulk biocomposites. These complex matrices were fabricated by direct encapsulating either ground plant particles or an ethanolic crude extract of the Australian toxic pasture plant Pimelea trichostachya in the biodegradable polymer poly(3-hydroxybutyrate-co-3-hydroxyvalerate). Proton nuclear magnetic resonance spectroscopy was initially employed to examine the chemical compositions of these complicated systems. Then, a more sensitive strategy was developed and validated by combining solid-phase extraction and ultrahigh-performance liquid chromatography hyphenated with a quadrupole Orbitrap mass spectrometer for the quantification of simplexin embedded in different biocomposites. Satisfactory linearity (R2 > 0.99) and recovery ranges (86.8–116%) with precision (relative standard deviations) of between 0.2 and 13% (n = 3) were achieved from seven biocomposites. The established protocol was further shown to be accurate and reliable in confirming the homogeneous distribution of the simplexin in different biocomposite formulations. A limited mass transfer of simplexin (< 3.5%) from one of the biocomposites into a simulated but sterilized in vitro rumen environment after a 10-day incubation was also revealed by utilizing the method. This quantitative analysis of targeted natural product within plant material-integrated polymeric platforms has potential application when controlled release is required in the bovine rumen and other biological systems.

Herein, natural fiber (energy reeds and rice straw) reinforced with phenol formaldehyde (PF) polymeric resin biocomposites are developed and reported in this study. The dimensions of energy reeds and rice straws used for this research were 0.5–1.66 mm and 0.1–3.55 mm, respectively. The hot-pressing technology was used for manufacturing the biocomposites. The proportions for mixing of rice straw/energy reed fibers in composite systems were 90/0, 54/36, 36/54, and 0/90 whereas remaining 10% were belong to PF resin. The nominal densities of the biocomposite panels were 680 kg/m3, however the actual densities were 713.655, 725, 742.79, and 764.49 kg/m3. The main objective of this study is to develop hybrid biocomposites from different proportions of energy reeds and rice straw fibers using PF resin and to find the convenient ratio and materials for biocomposites production. The obtained results demonstrate that mechanical properties and stability against the moisture increases with the increase of energy reeds loading in the composite systems. The biocomposite developed from 100% energy reeds provided the higher mechanical properties compared to 100% rice straw. The thermal and morphological properties of the produced biocomposite materials were investigated and found significant. The thermo-mechanical properties of the composite materials increase with the increase in energy reed fiber loading in composite system. Furthermore, the coefficient of variation (R2) also demonstrates a positive attributions of energy reed fibers loading in composite systems. Moreover, the overall performances of the developed biocomposite panels demonstrate them as potential and novel candidate to the composite community in the coming times. Graphical abstract

Nowadays, there is a need to obtain eco-friendly materials, especially plastics that are responsible for most of the environmental pollution. In this regard, poly(ɛ-caprolactone) PCL biocomposites with 10wt% of the oil (O) and/or 10wt% of the flour (F) extracted from the macaiba almond were produced in order to carry out a study of this polymer biodegradation acceleration. Mechanical properties (impact, traction and flexural), differential scanning calorimetry (DSC), thermogravimetric (TGA), water absorption, contact angle and analysis by optical microscopy (OM) and scanning electronics (SEM) were evaluated. Through these analyzes, it was noted that in the PCL–O biocomposite, the oil acted as a plasticizer in the PCL and in the PCL–FO biocomposite, there was an interaction among both phases. The samples biodegradation took place in accordance with ASTM G160-03 by burying impact specimens in compost for 60 days. The PCL–F biocomposite showed a mass loss of approximately 45%, followed by PCL–FO, with a loss of approximately 25%, both compositions also presented a rough morphology, with cracks and pores presence due to biodegradation from the microorganism action. These results have shown that the flour obtained from the macaiba almond is a promising agent for accelerating the PCL biodegradation.

A kind of novel electromagnetic shielding sandwich coating material with excellent electromagnetic interference shielding and coating properties was explored in this work. The interlayer was obtain...

Concerns about environmental problems have led to the development of biodegradable packaging. Food wastes as a byproduct could be a good source for biopolymers. This study aimed to describe the physical and antimicrobial features of nano biocomposite films based on orange waste powder (OWP) with different concentrations of nettle essential oil (NEO) (1.5 and 3%) as an antibacterial agent and cellulose nanofiber (CNF) (3 and 6%) as a structural reinforcement. Thus, Field emission scanning electron microscopy (FE-SEM), Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and differential scanning calorimetry analysis (DSC) were performed. Further, tensile strength, elongation at break, water vapor permeability, and antimicrobial properties were investigated. As a result, the addition of CNF improved the tensile strength and water barrier properties of the samples. Compared to the control film, adding NEO (3%) decreased the tensile strength but increased water vapor permeability and melting temperature. Moreover, the OWP-based film samples had an antimicrobial effect against five foodborne pathogens; this effect was increased considerably by enhancing the NEO concentration. In this regard, the maximum and minimum susceptibility was related to the Staphylococcus aureus and Salmonella enterica, respectively. In conclusion, orange waste could be used to produce an active film with improved physicomechanical and antibacterial properties by incorporating CNF and NEO.

Petroleum-based polymers have significantly problems to the environment due to it cannot degrade in the nature. Biopolymer become to interesting materials for replacing these materials for overcome these disadvantages. Here, we intend to study the biocomposite films of polylactic acid (PLA) blend polybutylene succinate (PBS) composited with ZnO nanoparticles. The chemical reaction and the water absorbency of biocomposite films were investigated by FT-IR spectroscopy and swelling ratio, respectively. The FT-IR results showed that the biocomposite films did not have any chemical reactions between polymers chains and ZnO nanoparticles. The swelling ratio of biocomposite films have proportionally with the contact time. The photocatalytic activity of biocomposite film was investigated by the methylene blue degradation in the aqueous solution. It was found that the efficacy of photocatalytic activity increased with increases in the contact time.

We developed a novel BW-CS/ZnHA biocomposite utilizing Beeswax-Chitosan and Zinc-hydroxyapatite nanoparticles (ZnHAP). The uniformed mixture of beeswax-chitosan and ZnHAP was freeze-dried to get a porous biocomposite. The fabricated biocomposite was characterized using FTIR, XRD, and SEM. Moreover, the antibacterial, swelling, biodegradations, viability, and cell proliferation capacity of the fabricated biocomposite was assessed. The biocomposite demonstrated upgraded swelling and antibacterial activity. The addition of ZnHAP accomplished the antibacterial activity. Biocompatibility studies were carried out using osteoblast cells and thus we proved the non-toxic nature of the biocomposite. Osteoblast cell adhesion investigations demonstrated that the cells were appended and infiltrated into the inside of the biocomposite. The obtained results encourage the use of these bandages for various types of wounds with infection and exudates.

Thermoplastic starch (TPS), as a natural based polymer, is known to have the capability to be used in biological applications due to its biocompatibility and biodegradability. In this study, mechanical properties of TPS are enhanced by incorporating bioactive β-tricalcium phosphate (β-TCP) particles for bone tissue engineering applications. Starch-based nanocomposites containing 3, 5, and 10 wt% of β-TCP nanoparticles (TT3, TT5, TT10) were made using a co-rotating twin-screw extruder. Dynamic light scattering (DLS) and X-ray diffraction (XRD) techniques were employed to analyze the nanocomposites. Moreover, degradability, swelling degree, and biomineralization in a simulated body fluid (SBF) were studied. To investigate the dispersion of β-TCP nanoparticles in the composite and biomineralization of the nanocomposites after incubation in SBF, scanning electron microscopy (SEM) and energy dispersive X-Ray analysis (EDX) were performed. Evaluation of mechanical properties of TPS and nanocomposites demonstrated that increase in β-TCP content enhanced mechanical properties. Besides, the bioactivity of these three nanocomposite materials was proven by nucleation of hydroxyapatite on the samples’ surface after incubation in simulated body fluid (SBF). Cytotoxicity test was done as well. Results of the current study have paved the way for the application of TPS/β-TCP composite as bone tissue engineering material.

Recently, bio-based polymer composites have been preferred instead of petroleum-based polymer composites due to increased sensitivity, awareness, and interest level in the fields of depletion of oil resources and environmental pollution. These eco-friendly materials, also called green composites, are reinforced with natural fibres and have superior properties such as biodegradability. In this paper, the effect of long-term ageing on mechanical properties of biocomposite material containing chicken feather fibre (CFF) as additive and poly(lactic acid) (PLA) as matrix is studied. The mechanical properties of pure PLA and CFF/PLA biocomposites, which are gradually increasing in mass concentrations of 2 %, 5 % and 10 %, have been investigated by tensile, compressive and hardness tests, and also the fracture surfaces were examined by SEM micrographs. The experimental results show that the long-term ageing effect causes the mechanical properties of pure PLA and CFF/PLA biocomposites to decrease. The lowest values of mechanical properties are found in the 5 % and 10 % CFF/PLA biocomposite materials that have the highest mass concentration of CFF.

This study deal with the development and investigation of a novel hybrid nano-shell plant fiber biocomposite. Nano-calcium carbonate CaCO3 ranging from 1 to 5 wt% and 20 wt% banana fiber-filled hybrid biocomposite were prepared using a hand lay-up process followed by applying load on a closed mold. Nano-CaCO3 of near-uniform size and shape was synthesized from Achatina Fulica through a mechanochemical technique. The effect loading fiber of uniform 30 mm size on the mechanical, physical, thermal properties of greenpoxy composite was investigated. The influence of nano-CaCO3 loading (1 to 5 wt%) on banana fiber-filled greenpoxy composite, dynamic mechanical properties, tensile, flexural, impact strength was further investigated. The result showed that the loading of banana fiber improved mechanical properties and negatively affected temperature dependence storage modulus, loss modulus, and tan δ. Better load carrying and stress distribution capacity of the fiber within the biocomposites can be attributed to the high strength and stiffness observed for these series. The poor thermal properties of banana fiber can be ascribed to a decrease in the temperature dependence properties. The loading of nano-CaCO3 improved most of the banana-filled greenpoxy biocomposite, and hybrid composite with 2 wt% nano-CaCO3 offered superior properties. Uniform dispersion, excellent matrix/nano-CaCO3/banana fiber adhesion provided a strong structure, resulting in improved mechanical and temperature-dependant properties.

Being credited with the most extensively studied polysaccharide polymer and promising candidate for versatile applications, chitosan has proved to be a standalone material with loads of diversified properties in various structural forms such as blends and composites. Considering the abundance of this biopolymer and its non-toxic nature, exploiting chitosan offers two-folded benefits – environment friendliness and fabrication as per the need. Alkaline deacetylation of chitin produces chitosan as a polymer that can be tuned to a great extent as per the requirement by altering the degree of deacetylation (DDA) and molecular weight (MW). This biopolymer has been widely investigated for potential application in the food and biomedical fields due to its antimicrobial and antibacterial properties. Chitosan based composite films incorporated with different natural extracts have shown significant enhancement in the physical and biological activities as reported by different studies. The current study reviews recent developments and investigations of chitosan based biocomposite films incorporated with different natural extracts emphasizing on the improvement of physical and biological properties and its applications.

The paper reports a sustainable, fast and efficient methodology to treat natural hemp fibers (HF) using a mechanochemical approach. Mechanical milling was used to carry out an alkaline attack on HFs for 30 minutes at ambient temperature. Composites HF/pectins were prepared by varying the fiber weight fraction (3%; 7.5%; 10%; 20% w/w by weight). The improvement in thermal degradation, mechanical and barrier properties to water vapor was correlated with the fiber volume fraction and mainly due to the improved fiber-matrix adhesion. The fibers-matrix interaction was then evaluated by analyzing and modeling the mechanical properties using several mathematical models: a modified Nielsen and Pukanszky and Smith models. Sorption isotherms to water vapor were analyzed through a modified Guggenheim, Anderson, de Boer (GAB) model where a new parameter, α, was introduced to consider the heterogeneity of the system. Finally, a modified Burgemman model was used to fit the experimental data and support the improvement in water diffusion with fiber loading.

The transition-metal dichalcogenides (TMDCs) like MoS2 and WS2 are a new and interesting class of materials and show considerable promise for use in a wide variety of fields, including nanomedicine for cancer. The eco-friendly, biodegradability, toxicity, and antimicrobial activity remain an open issue. Herein, we focused on the current demands of two dimensional (2D) TMDCs and produced high-quality, few-layered MoS2 nanosheets. Noble metal Ag incorporated into the 2D-CS/MoS2 NC by the liquid exfoliated process. The manufactured CS/MoS2/Ag hybrid NC showed excellent antibacterial activity against two microorganisms such as Gram-positive (21, 27, and 33 mm) and Gram-negative bacteria (23, 30, and 39 mm). The CS/MoS2/Ag hybrid NC was designed to have significant antibacterial activity against E. coli bacteria than S. aureus. Furthermore, the hybrid NC has a 74.18% cell inhibition against MCF-7 cancer cells. According to the literature relevant, it is the first extensive experimental analysis on the nano-bio interaction of 2D TMDCs nanomaterials in MCF-7 breast cancer cells.

Green reinforcement in biopolymer for enhanced industrial application is on the increase. Bio-precipitated CaCO3 was synthesised via the process of microbially-induced calcium carbonate precipitation using Bacillus sp. strain. The bio-precipitated CaCO3 (B-PCC) and conventional CaCO3 precipitates (C-PCC) reinforcement effect on the properties of Eucheuma cottonii film was analysed and compared. The biocomposite films were fabricated using a solvent casting technique. The physicomechanical, thermal and biodegradability performances of B-PCC and C-PCC incorporated E. cottonii film with increasing fillers' contents [0.05, 0.10, 0.50, 1.00, 2.00 (wt.%)] were determined and compared through a range of testing include water vapour permeability (WVP), contact angle using sessile drop method, scanning electron microscopy (SEM), tensile, elongation, Young's modulus, thermogravimetric analysis (TGA), and soil burial test. A further comparison was made between the E. cottonii biocomposite film with the existing biodegradable mulch films to evaluate its potential application using wet cup method. Results revealed that biocomposite films embedded with 0.1% B-PCC appeared to exhibit higher water barriers and hydrophobicity behaviours than those embedded with C-PCC. However, the mechanical strength and thermal stability were slightly lower than those embedded with C-PCC. E. cottonii biocomposite films, especially those embedded with 0.1 wt. % B-PCC has shown the potential in agricultural mulch film as it promoted better biodegradation and tensile strength by 34.24% and 20% respectively compared to the existing biodegradable PLA/PBAT mulch film, making it a promising alternative to the conventional plastic to mitigate plastic pollution.

In this study, a light cross-linkable biocomposite scaffold based on a photo-cross-linkable poly (propylene fumarate) (PPF)-co-polycaprolactone (PCL) tri-block copolymer was synthesized and characterized. The developed biodegradable scaffold was further modified with β-tricalcium phosphate (β-TCP) bioceramic for bone tissue engineering applications. The developed biocomposite was characterized using H nuclear magnetic resonance and Fourier transform infrared spectroscopy. Moreover, the bioceramic particle size distribution and morphology were evaluated using Brunauer-Emmett-Teller method, X-ray diffraction, and scanning electron microscopy. The mechanical properties and biodegradation of the scaffolds were also evaluated. Cytotoxicity and mineralization assays were performed to analyze the biocompatibility and bioactivity capacity of the developed biocomposite. The characterization data confirmed the development of a biodegradable and photo-cross-linkable PCL-based biocomposite reinforced with β-TCP bioceramic. In vitro analyses demonstrated the biocompatibility and mineralization potential of the synthesized bioceramic. Altogether, the results of the present study suggest that the photo-cross-linkable PCL-PPF-PCL tri-block copolymer reinforced with β-TCP is a promising biocomposite for bone tissue engineering applications. According to the results, this newly synthesized material has a proper chemical composition for further clinically-relevant studies in tissue engineering.

2,2,6,6-Tetramethylpiperidin-1-yl oxyl (TEMPO)-oxidized beta-chitin nanofibrils (T-ChNF) are novel nanofibrils of high strength and stiffness and can also enhance the adsorption of chitosan in mate ...

This paper reports the effect of lignocellulosic flour and talc powder on the thermal degradation behavior of poly (lactic acid) (PLA) by thermogravimetric analysis (TGA). Lignocellulosic flour was obtained by grinding Opuntia Ficus Indica cladodes. PLA/talc/ Opuntia Ficus Indica flour (OFI-F) biocomposites were prepared by melt processing and characterized using Wide-angle X-ray scattering (WAXS) and Scanning Electron Microscope (SEM). The thermal degradation of neat PLA and its biocomposites can be identified quantitatively by solid-state kinetics models. Thermal degradation results on biocomposites compared to neat PLA show that talc particles at 10 wt % into the PLA matrix have a minor impact on the thermal stability of biocomposites. Loading OFI-F and Talc/OFI-F mixture into the PLA matrix results in a decrease in the maximum degradation temperature, which means that the biocomposites have lower thermal stability. The activation energies (Ea) calculated by the Flynn Wall Ozawa (FWO) and Kissinger Akahira Sunose (KAS) model-free approaches and by model-fitting (Kissinger method and Coats-Redfern method) are in good agreement with one another. In addition, in this work, the degradation mechanism of biocomposites is proposed using Coats-Redfern and Criado methods.

Collagen- and bioceramic-based composites have been widely used in hard tissue engineering because they are analogous to the organic/inorganic constituents of native bones. However, biocomposites based on collagen and bioceramics show low mechanical stiffness and limited osteogenic activities. To elevate the low biophysical and biological activities, we have introduced a new biocomposite structure. Herein, we propose a biocomposite mimicking not only the physical structure of the extracellular matrix (ECM) structure but also the biochemical components of native bone tissues. Several components including fibrillated collagen, calcium-deficient hydroxyapatite (CDHA) obtained from α-tricalcium phosphate hydrolysis, and human umbilical cord serum (hUCS) were used to generate a unique structure of the biocomposite. The 3D-printed composites were topographically similar to the nanofibrous ECM and exhibited a mechanically stable structure. We also evaluated the in vitro biocompatibilities of the biocomposite using human adipose stem cells and found that the collagen/hUCS/CDHA scaffold accelerated the in vitro osteogenic differentiation of human adipose-derived stem cells and in vivo osteogenesis in a mastoid obliterated rat model.

Agricultural crop residues are known to be a renewable source of value-added products, and their application as a bio-based production chain type in the circular bioeconomy system is considered efficient in minimizing environmental problems. Value-added products, such as cellulose nanofibers (CNFs) from lignocellulose in agriculture residues, have been widely applied in the production of membranes that have desirable physicochemical characteristics. In this work, orange bagasse residue was used to obtain cellulose nanofiber and then applied to starch membranes as a mechanical reinforcement. The 1-methylimidazolium ionic liquid was used as biomass treatment for cellulose nanofiber isolation, and then two starch membranes were prepared with 5% (v/v) of cellulose nanofiber solution at 70 °C and 90 °C by the casting method. The cellulose nanofibers and membranes were characterized by scanning electron microscopy, fourier transform infrared spectroscopy, thermogravimetric analysis, and X-ray diffraction. Thickness and tensile tests were applied to the membranes. Cellulose nanofibers less than 100 nm in diameter were obtained by the 1-methylimidazolium treatment, and the characterization analyses showed that the CNFs were incorporated into the membranes, which improved their mechanical resistance and thermal degradation capacity. However, membrane 1, which was prepared at 70 °C, showed a particularly significant gain in tensile strength.

The use of nanostructured materials is already well-known as a powerful tool in the development of electrochemical sensors. Among several immobilization strategies of nanomaterials in the development of electrochemical sensors, the use of low-cost and environmentally friendly polymeric materials is highlighted. In this context, a new nanostructured biocomposite electrode is proposed as an electrochemical sensor for the analysis and determination of tetracycline. The composite electrode consists of a modified glassy carbon electrode (GCE) with a nanodiamond-based (ND) and manioc starch biofilm (MS), called ND-MS/GCE. The proposed sensor showed better electrochemical performance in the presence of tetracycline in comparison to the unmodified electrode, which was attributed to the increase in the electroactive surface area due to the presence of nanodiamonds. A linear dynamic range from 5.0 × 10 − 6 to 1.8 × 10 − 4 mol L−1 and a limit of detection of 2.0 × 10 − 6 mol L−1 were obtained for the proposed sensor. ND-MS/GCE exhibited high repeatability and reproducibility for successive measurements with a relative standard deviation (RSD) of 6.3% and 1.5%, respectively. The proposed electrode was successfully applied for the detection of tetracycline in different kinds of water samples, presenting recoveries ranging from 86 to 112%.

The polypropylene with load of reinforcement of curauá fiber (PP-curauá) is a compound developed to be applied in the process of injection of automotive plastic parts. Polypropylene composites reinforced with mineral fillers (talc) or glass fibers have been widely applied in this segment. However, natural fibers are an important alternative considering the aspects of sustainability, recyclability, abundance and low cost, when compared with glass fibers, and industrial talc. This study was prompted by the growing need for materials that meet the constant cycles of use, disposal and reuse, and avoid the harmful effects on the environment. The mechanical properties of a curaua fiber and polypropylene-based ecocomposite reprocessed one, three and five times were assessed, since reprocessing is known to change the strength of these materials. Pure polypropylene (0%) and ecocomposites with 10 and 30 wt% of fiber were submitted to tensile and three-point bending tests. The results showed that polypropylene ecocomposites with 30% curaua fibers exhibited a higher modulus of elasticity. Moreover, reprocessing did not significantly affect the ecocomposite properties, demonstrating their viability for reuse.

For the restoration of calvarial bone defects, we have developed a biodegradable, osteogenic biocomposite material and assessed the degree of bone regeneration in rats following implantation and therapy with hyperbaric oxygen (HBO). Characterization of nano-hydroxyapatite (n-HAP) and nano-hydroxyapatite/carboxymethyl chitosan/zoledronic acid (n-HAP/CMC/ZOL) biocomposites using Fourier-transform infrared spectroscopy (FTIR) showed the existence of the apatite phosphate group and the spectra of X-ray diffraction (XRD) displayed a polycrystalline existence. The morphological characterization of n-HAP and biocomposite using scanning electron microscopy (SEM) showed the porous spherical shape, and the inclusion of calcium and phosphate as the major elements was shown by the energy dispersive X-ray (EDX) spectrum. Using osteoblast MG-63 cells, the n-HAP/CMC/ZOL biocomposite was evaluated to show effective cytocompatibility. To assess potential effects of hyperbaric oxygen (HBO) on biocomposite substitutes were applied to standard bone defects in rat tibiae. The findings indicate that, contrasted with the monitor, there was substantially more new bone forming in the HBO group. The use of this novel material with HBO treatment may offer an alternative to autogenous bone grafting.

The low density polyethylene-chitosan nanoparticles (LDPE/CHNP) biocomposite was applied as a biosorbent for the adsorption of Congo red (CR) anionic dye and methyl red (MR) a cationic dye an in single and binary system. The effect of parameter pH, contact time, initial concentration, adsorbent dosage and temperature were studied on the two dyes in single and the binary component system. Kinetic studies showed that adsorption on LDPE/CHNP in a single and binary-component system follows pseudo-second order kinetics. The values of CR in single and binary system were gotten to be 0.9996 and 0.9984 respectively, while the values of MR in single and binary system were 0.9994 and 0.9983 respectively. The adsorption equilibrium study was tested with both Langmuir and Freundlich isotherm and the result showed they agree more with Langmuir have an values for CR in single and binary system to be 0.9995 and 0.9991 respectively, while the values of MR in single and binary system were 0.9954 and 0.9983 respectively; which implies that the adsorptions were more of chemisorption than physiosorption reaction. In the single and binary systems, the result reveals that CR had higher adoption efficiency than MR which could be because the chelation between cations and chitosan chains, which decreased the electrostatic interaction between Methyl red and chitosan nanoparticles of the biocomposite. The LDPE/CHNP biocomposite has proved to be an efficient adsorbent for CR (anionic dye) and MR (cationic dye) in single and two-component system which are frequently encountered composition of industrial effluents.

Urea–formaldehyde (UF) resins are often reinforced with natural fibers or nanostructures such as cellulose microfibrils (CMFs) to improve their mechanical and physical properties in wood panels. However, the high-water content in these suspensions is a limitation on applications in thermosetting resins. The innovative technology investigated here consists of the in-situ production of a methanediol-based suspension of CMFs through a mechanical process and its incorporation during resin synthesis. We sought to maintain the physicochemical properties and the basic chemical composition of the resin. The synergy between the resin and CMFs provided a shielding effect and a greater storage modulus (E’). We demonstrate that this approach is robust through standard viscoelastic, physical, and mechanical tests. Likewise, a methanediol-based CMF suspension used to synthesize UF resin was effective to reduce formaldehyde emission during the resin cure reactions. Finally, the bio-based composites manufactured with this UF resin containing CMF had better performance due to increased internal bond strength by up to 15%, reduced water absorption by up to 8%, and reduced formaldehyde emission by 30% at environmental temperature.

Objectives. The purpose of this analytical review is to evaluate the market for osteoplastic materials and surgical implants, as well as study the features of new-generation materials and the results of clinical applications.Methods. This review summarizes the volumes of research articles presented in the electronic database PubMed and eLIBRARY. A total of 129 scientific articles related to biological systems, calcium phosphate, polymer, and biocomposite matrices as carriers of pharmaceutical substances, primary recombinant protein osteoinductors, antibiotics, and biologically active chemical reagents were analyzed and summarized. The search depth was 10 years.Results. Demineralized bone matrix constitutes 26% of all types of osteoplastic matrices used globally in surgical osteology, which includes neurosurgery, traumatology and orthopedics, dentistry, and maxillofacial and pediatric surgery. Among the matrices, polymer and biocomposite matrices are outstanding. Special attention is paid to the possibility of immobilizing osteogenic factors and target pharmaceutical substances on the scaffold material to achieve controlled and prolonged release at the site of surgical implantation. Polymeric and biocomposite materials can retard the release of pharmaceutical substances at the implantation site, promoting a decrease in the toxicity and an improvement in the therapeutic effect. The use of composite scaffolds of different compositions in vivo results in high osteogenesis, promotes the initialization of biomineralization, and enables the tuning of the degradation rate of the material.Conclusions. Osteoplastic materials of various compositions in combination with drugs showed accelerated regeneration and mineralization of bone tissue in vivo, excluding systemic side reactions. Furthermore, although some materials have already been registered as commercial drugs, a plethora of unresolved problems remain. Due to the limited clinical studies of materials for use on humans, there is still an insufficient understanding of the toxicity of materials, time of their resorption, speed of drug delivery, and the possible long-term adverse effects of using implants of different compositions.

A bio-functional composite of vitamin B12 with graphene and ionic liquid in chitosan solution was prepared for the first time. The composite was tested for its spectroscopic and electrochemical signatures, which establish the presence of vitamin B12 in its native structure, with its Co-metal centre accessible for heterogeneous electron transfer. Our electrochemical investigations establish that with 1-butyl-3-methylimidazolium tetrafluoroborate (BMImBF4) as electrolyte, the Co(III) metal centre of the biocomposite film can be reduced to electrocatalytically active Co(I) at potentials that are significantly less negative than that reported for solution phase vitamin B12. The biocomposite modified electrode was observed to exhibit excellent electrocatalytic activity toward the electroreduction of halocarbons viz. benzyl bromide, dibromoethane and trichloroacetic acid. The presented investigations indicate that the biocomposite modified electrode minimizes the probability for undesired solution phase reactions of electrogenerated reactive intermediates during electroreduction of dihaloalkanes. This feature is expected to have profound implications on product profile/yield for selective electroreductive reactions of dihaloalkanes. Our comparative electrocatalytic activity investigations for the chosen halocarbons suggest a synergistic activity of the components employed for the fabrication of the biocomposite modified electrode.

Clove essential oil (CEO) was immobilized in mesoporous silica nanoparticles (MSN) (0, 1, 2, and 3 wt%) and incorporated into poly(lactic acid) (PLA) matrix via a casting method. The functional properties including mechanical property, thermal property, antimicrobial property, and CEO release behavior of the PLA nanocomposite film were investigated. The compatibility of CEO-loading MSN with PLA was verified by scanning electron microscopy analysis. The tensile strength, tensile module, and glass transition temperature of the MSN/CEO/PLA composite film was improved with the increase in MSN content. The release study indicated that the MSN/CEO/PLA composite films exhibited sustained release profile of CEO. The MSN/CEO/PLA films demonstrated efficient antimicrobial activity. The results indicated that CEO immobilized MSN incorporated PLA nanocomposite film showed promising features for active food packaging material.

The demand of antimicrobial active packaging is escalating due to the needs of improving quality and shelf life of food. In this work, sugar palm starch (SPS)/sugar palm nanocrystalline cellulose (SPNCC) incorporated with cinnamon essential oil (EO) biodegradable nanocomposite films were prepared by using solvent casting method. Mechanical properties test revealed that films incorporated with cinnamon EO showed improved tensile strength and tensile modulus values from 4.8 to 5.3 MPa and 122.49–130.52 MPa respectively. Additionally, the density and moisture content were reduced from 1.38 to 1.31 g/cm3 and from 13.65 to 12.33% respectively. The antimicrobial test was carried out by agar disc method (ADM) to evaluate the inhibition effect of the films on the gram positive bacteria, gram negative bacteria and yeast. The result suggested that The higher the amount of EO used (2.0 wt) yielded, the higher the inhibition zone occurred for B. subtilis, S. aereus and E. coli, which were 7.85, 6.63, and 7.43 mm respectively. Overall, cinnamon EO incorporated SPS/SPNCC biodegradable nanocomposite film is a good candidate as an alternative for active packaging material.

Chitosan/gelatin (CG) composite sponges containing oxidized cellulose fibers (OF) crosslinked with tannic acid were fabricated by freeze-drying as hemostatic agents. The cellulose fibers were oxidized by 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO). Fourier transform infrared spectroscopy proved the formation of carboxyl groups on cellulose fibers. Addition of OF increased the swelling ratio of CG sponges. The amount of bleeding was measured after 10 s on hepatic trauma in a rat model. To assess the in vivo bio-absorbability of the samples, the sponges were implanted in the liver for 21 days and the volume of the repaired tissue was measured from histopathological analysis. The biocomposite sponge fabricated by addition of 30% OF suspension into CG solution showed the lowest amount of bleeding and the highest bio-absorbability after 21 days. The findings of this study indicate that the addition of OF into CG increased the clotting capability as well as the bio-absorbability of the biocomposite sponges.

In this study we have recycled two types of waste papers, newspapers and magazines, to prepare paperboard sheets for multipurpose applications. The recycling procedure succeeded in removing most of inorganic contaminants via de-inking process. To enhance the flame retardant ability of paperboard sheets, treatment with varying concentrations (1, 3 and 5 % wt/vol) of organophosphorus-silane compound in the absence and presence of starch (0.2 % wt/vol) was done. The thermal proofing properties of paperboard sheets have been modified after treatment with organophosphorus-silane compound and starch/organophosphorus-silane biocomposite. The results showed that, 3 % (wt/vol) was the minimum concentration to accomplish fire retardancy of paperboard sheets. The addition of starch to the organophosphorus-silane compound enhances the physicomechanical properties of modified paperboard sheets. The paperboard sheets treated organophosphorus-silane compound and starch/organophosphorus-silane biocomposite showed dissimilar activities against Bacillus subtilis, Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa. Various analyses were performed to study the physical, chemical, mechanical and thermal properties of the prepared paperboard sheets.

Sustainable biocomposites have been developed from poly (3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH) by solution-casting using montmorillonite (MMT) and acetylated cellulose nanocrystals (ACNs) as reinforcing agents. The morphological, thermal, crystallization behavior, tensile and barrier properties of biocomposites (A@MP) were evaluated. The morphological characterizations revealed the improved dispersion of ACNs in A@MP matrix. The ternary biocomposite showed up to 63.4% and 49 °C improvements in tensile strength and the maximum thermal decomposition temperature, respectively, compared to those of neat PHBH. Furthermore, the oxygen permeability (OP) and water vapor permeability (WVP) of A@MP with 2.5wt% ACN loading reached 0.60 × 103 mL·μm/m2·d·atm and 1.06 × 10–8 g/m·d·Pa, respectively. Overall, the research results have demonstrated the high potential of PHBH ternary biocomposite for food packaging applications.

Natural cellulosic fibres, such as kenaf, have potential for use as replacement of man-made fibres in polymeric composites. The rapid depletion of synthetic resources, such as petroleum, and the growing consciousness of global environmental problems related to synthetic products push toward the acceptance of natural fibres as biocomposite components. Kenaf (Hibiscus cannabinus L.) is a multipurpose hibiscus species used to make engineered wood, clothing, packing material, rope and twine. Kenaf is essentially made up of cellulose (about 70%), predicting its excellent mechanical performance. Kenaf fibres are chemically treated before mixing with other polymer resins to enhance their fibre properties. Based on the previous literature, the effect of chemical treatment on the dynamic mechanical performance of kenaf cellulosic biocomposites remains unexplored. The present review focuses on the recent works on the influence of major chemical treatments used on kenaf fibre, such as alkaline, silane and acetylation on fabricated biocomposites. The present review also unveils other chemical treatments (e.g. zein and amino acid) and combined treatments on the fibre to improve the biocomposites’ dynamic mechanical behaviour.

Agro-industrial residues are difficult to dispose of or reuse; however, it can be used to generate goods such as biodegradable packaging. The aim was to isolate and characterize fibers from corn stalks, husks, and cobs, and apply them in starch composite films (control, 5 g 100 g−1, 10 g 100 g−1, 15 g 100 g−1 and 20 g 100 g−1). The cellulose fibers were isolated by alkaline treatment and characterized by its morphology, crystallinity, and chemical structure, showing materials with different lengths and diameters, and intermediate crystallinity. The composite films were evaluated by morphological characteristics, water-solubility, water vapor permeability, chemical structure, mechanical properties, and sorption isotherms. Generally, fibers reinforcement decreased moisture adsorption. The tensile strength and Young's modulus increased adding straw fiber (5 g 100 g−1 and 10 g 100 g−1) and stalk and cob fibers (5 g 100 g−1). The use of cellulose fibers in films is important to expand and improve the current lack of biodegradable packaging.

Reactive Blue 19 (RB19) removal from synthetic textile wastewater was investigated by using a CoFe2O4@methylcellulose (MC) activated with peroxymonosulfate (PMS) and the ultrasound process. CoFe2O4@MC as a new magnetic nano-biocomposite was prepared using a convenient and rapid microwave-assisted technique in presence of MC as a green biopolymer, and characterized by FESEM, EDS, Mapping, TEM, FTIR, XRD, TGA, VSM, and BET techniques. Then, the effective parameters including pH (4–10), reaction time (0–30 min), CoFe2O4@MC (0.2–1 g/L), and PMS concentration (0.5–10 mM) in the sonocatalytic degradation of RB19 were investigated. The maximum removal efficiency of RB19 was achieved as 97% for synthetic wastewater under the optimal conditions of pH 4, CoFe2O4@MC dosage (0.6 g/L), reaction time = 30 min, and PMS (5 mM) in the presence of ultrasonic waves (60 kHz) at the ambient room temperature of 22 °C. The CoFe2O4@MC catalyst was simply isolated using a magnet and recycled with no remarkable loss of catalytic activity following usage in four runs. The results showed that the CoFe2O4@MC sonocatalysis process is practical, and effective for degrading complex and resistant dyes such as RB19.

The current global proposal for withdrawing polymers with high resistance to degradation and from fossil sources from disposable appliances, as well as the increasing trend of cheese production and whey generation, are some of the incentives for using whey proteins to produce biodegradable packaging films. Brittleness and poor water barrier limit the application of whey protein isolate (WPI) films in the food packaging sector. The addition of polyvinyl alcohol (PVOH) to WPI film, making a blend, improves flexibility but maintains poor water barrier and tensile strength. In this work, to make WPI/PVOH blends more suitable for food packaging applications, films of WPI/PVOH were reinforced with up to 4% of colloidal nano-silica (NS) for improvement of mechanical resistance and water vapor barrier, thus producing a novel biocomposite in terms of composition. At 4% of NS, the values obtained for tensile strength and tensile modulus were 10.2 and 78.2 MPa, being suitable for food packaging application when compared to commercial polymers currently used as packaging. An expressive reduction of water sorption (17% of decrease) and water vapor permeability (40% of reduction) was observed at 4% of NS, increasing the efficiency in keeping integrity during application and leading to a material with a higher water vapor barrier. The addition of 4% of NS in WPI/PVOH films is indicated to improve tensile strength and water barrier, thus increasing its application potential as food packaging.

A green biocomposite (BTF-i-ACS) consisting of banana trunk fibers (BTF)-infused acidified chitosan (ACS) was prepared. The biocomposite was characterized by means of Fourier Transform Infrared Spe...

Holocellulose fibers produced by mild delignification form strong fiber networks, without beating or dry-strength agents. Recently, sequential batch delignification using peracetic acid (PAA) on finely cut wood sticks resulted in high-quality holocellulose fibers. Here, single step PAA delignification is developed for wood chips, which is simpler and can be used for larger fiber batches (400 g) with similar, high yield (60%). Such fibers have 1.4% lignin, 25% hemicelluloses content and well-preserved cellulose and hemicellulose molar mass. The corresponding paper sheet materials with a porosity of ~ 50%, have a Young’s modulus of 9 GPa and a strength of 90 MPa. Holocellulose fibers can now be readily investigated for use in larger scale paper, molded fiber and polymer biocomposite materials applications, or for cellulose nanofibril preparation.

Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) is a copolymer synthesized by Bacillus megaterium co-utilizing cheese whey and food waste hydrolysate for its one-step production. The optimized substrate ratio of 60:40 (v/v) manifested maximum biomass of 3.09 ± 0.12 g/L and PHBV yield of 2.0 ± 0.3 g/L. Batch kinetics study revealed maximum biomass and PHBV yield of 3.05 ± 0.07 g/L and 2.175 ± 0.06 g/L respectively, with 71.43 ± 0.28% g/g PHBV content. The integration of corncob-derived nanocellulose into PHBV was confirmed by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), and X-ray diffraction (XRD) analysis. Thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) analyzed the thermal characteristics of the PHBV biocomposite, where the highest degradation temperature was obtained at 790 °C, thus exhibiting high thermal stability. The mechanical properties such as Young's modulus, elongation at break, and tensile strength of the biocomposite was comparatively higher than PHBV and was found to be 40 MPa, 5.310%, and 11.110 MPa, respectively. The enhanced thermal and mechanical characteristics of PHBV biocomposite proves that the corncob-derived nanocellulose can be employed as a reinforcing agent.

Thanks to good mechanical performances, high availability, low cost and low weight, the agave sisalana fiber allows to obtain biocomposites characterised by high specific properties, potentially very attractive for the replacement of synthetic materials in various industrial fields. Unfortunately, due to the low strength versus transversal damage processes mainly related to the matrix brittleness and/or to the low fiber/matrix adhesion, the tensile performance of random short fiber biocomposites are quite low, and to date most of the fiber treatments proposed in literature to improve the fiber-matrix adhesion, have not led to very satisfactory results. In order to overcome such a drawback, this work in turn proposes the proper introduction of low fractions carbon nanotubes to activate advantageous improvements in matrix toughness as well as fiber-matrix bridging effects, that can both lead to appreciable increments of the tensile strength.Systematic experimental static and fatigue tests performed on high quality biocomposites obtained by an optimized compression molding process, have shown that the introduction of 1% of carbon nanotubes is sufficient to gives significant improvement in both stiffness and static tensile strength, respectively by approximately 28% and 30%. Furthermore, toughening the biocomposite with 1% of nanotubes results in an appreciable enhancement in lifetime of at least 3 orders of magnitude. Biocomposites with 2% of CNTs show instead more limited improvement of 13% in stiffness, 6% in strength and 150% in lifetime. Also, a thorough analysis of the damage processes by SEM micrographs, as well as of the main fatigue data, has allowed to determine the model that can be used to predict the fatigue performance of such biocomposites.

Owing to develop the utilization of biowaste materials and minimize the usage of plastic materials, Orange peel Powder (OPP) biowaste is chosen as filler material along with Polyvinyl Alcohol (PVA) as a matrix to form biocomposite films. To stretch its applications to antibacterial applications the metal nanoparticles were incorporated by the in-situ generation of Ag by reducing the various concentration of the aqueous solution of AgNO3 to fabricate novel PVA/OPP/(1 mM to 5 mM)AgNPs hybrid biocomposite films. The fabricated biofilms were undergone the antibacterial test, mechanical test, and characterized by FESEM, FTIR, XRD & thermal analysis. The FESEM images clarify the homogenous distribution of filler materials in the PVA matrix and binding between the filler materials & matrices. FT-IR spectrum illustrates, there is no functional group change in the films by the inclusion of AgNPs as compare to the PVA/OPP films and indicates the strong adhesion and well dispersion of filler materials. XRD patterns confirm the presence of Ag and accentuated the crystallite size of generated AgNPs in the films as 23.44 nm, 25.59 nm, 26.25 nm, 28.17 nm, and 28.42 nm. Thermal analysis of the films shows improved thermal stability as well as glass transition temperature of the composite films included with AgNPs, also the considerable increase in the tensile strength and tensile modulus of the PVA/OPP/AgNPs films as compared to the neat PVA, PVA/OPP films. As compare to neat PVA and PVA/OPP films, with the increase of concentration of AgNO3 source solution antibacterial activity of the PVA/OPP/AgNPs films increases against gram-negative and gram-positive bacteria. With the above-improved results by the inclusion of Ag nanoparticles, this hybrid biocomposite films can be utilized in food processing industries