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Herein, the nanolignin-containing cellulose nanofibrils (LCNF)-enabled ratiometric fluorescent bio-nanocomposite film is developed. Interestingly, the inclusion of LCNF in the cellulose-based film enhances the detecting performance of food freshness, such as high sensitivity to biogenic amines (BAs) (limit of detection (LOD) of up to 1.83 ppm) and ultrahigh discernible fluorescence color difference (ΔE = 113.11). The underlying mechanisms are the fluorescence resonance energy transfer (FRET), π - π interaction, and cation - π interaction between LCNF and fluorescein isothiocyanate (FITC), as well as the increased hydrophobicity due to lignin, which increases the interactions of amines with FITC. Its color stability (up to 28 days) and mechanical property (49.4 Mpa) are simultaneously improved. Furthermore, a smartphone based detecting platform is developed to achieve access to food safety. This work presents a novel technology, which can have a great potential in the field of food packaging and safety., Competing Interests: Declaration of competing interest It is the original work of the authors. All the authors mutually agree that it should be submitted to Food Chemistry The manuscript has not been published or presented elsewhere in part or in entirety and is not under consideration by another journal. The authors declare that they have no conflict of interests. There is no research involving Human Participants and/or Animals., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

High-quality boron nitride nanosheets (BNNSs) were exfoliated via eco-friendly holocellulose nanofibrils (HCNFs) assisted ultrasound treatment in water. The resultant H-BNNSs possessed high yields (23.4%), few surface defects, a high aspect ratio (~134), and excellent dispersibility in water (Zeta potential, -53.5 mV). Furthermore, H-BNNSs were functionalized by liquid metal (Gallium, Ga) dominated interface engineering and assembled with cellulose fibers into Ga@H-BNNSs filled nanocomposite films. Owing to the well-designed interface engineering, the obtained nanocomposite films exhibited outstanding integrated performance, especially excellent in-plane thermal conductivity (11.78 W m -1  K -1 ), and had great potential in the thermal management of flexible electronics., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Recently, great efforts have been devoted to developing conductive adhesive hydrogels to meet the needs of various applications. However, grand challenges remain in achieving anisotropic hydrogels simultaneously featuring multiple properties using natural polymers and renewable resources. Here, a cellulose-based conductive hydrogel with strong, ultrastretchable, and adhesive properties is prepared via a simple magnetic field-induced strategy. This strategy involves the formation of a suspension mixture with well-oriented cellulose-polydopamine nanocomposites under magnetic fields, followed by rapid orientation via covalent crosslinking. The tensile strength of the oriented hydrogel in longitudinal direction is ~0.22 MPa, which is ~1.4 times higher than that in radial direction. Moreover, the hydrogel shows good cyclic loading-unloading ability, high conductivity (6.9 ± 0.6 S m -1 ), and strong adhesion (71 kPa). The hydrogel also shows significant anisotropic properties and made it a versatile platform for wearable sensors to monitor large and subtle human motion in the foreseeable future., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Ionic conductive hydrogel with multifunctional properties have shown promising application potential in various fields, including electronic skin, wearable devices and sensors. Herein, a highly stretchable (up to 2800% strain), tough, adhesive ionic conductive hydrogel are prepared using cationic nanocellulose (CCNC) to disperse/stabilize graphitic carbon nitride (g-C 3 N 4 ), forming CCNC-g-C 3 N 4 complexes and in situ radical polymerization process. The ionic interactions between CNCC and g-C 3 N 4 acted as sacrificial bonds enabled highly stretchability of the hydrogel. The hydrogel showed high sensitivity (gauge factor≈5.6, 0-1.6% strain), enabling the detection of human body motion, speech and exhalation. Furthermore, the hydrogel based self-powered device can charge 2.2 μF capacitor up to 15 V from human motion. This multifunctional hydrogel presents potential applications in self-powered wearable electronics., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Flexible electronics products have attracted wide attention because of their excellent flexibility, conductivity and stability. In this study, the liquid phase reduction method was used to in situ reduce fractal-structured silver particles (FSSPs) on cellulose surface to prepare conductive paper with excellent conductivity, and good stability and flexibility. The experimental results show that when the mass ratio of silver to cellulose was 1.5:1, the sheet resistance of conductive paper is as low as 0.02 Ω·sq -1 , and the conductivity reaches 1041.33 S cm -1 , which shows excellent conductivity. In order to expand the application of conductive paper in the field of flexible wearable electronic products, the mechanical stability and oxidation resistance of conductive paper were tested. The results show that the conductive paper has good stability and is expected to replace the flexible electronics products made of plastic., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Bacterial breeding is the main cause of food perishability, which is harmful to human health. Silver nanoparticles (AgNPs) are one of the most widely used antimicrobial agents, but they are easy to release and cause cumulative toxicity. In this work, with corn stalk as green reductant and GO as template, a simple electrostatic self-assembled sandwich-like chitosan (CS) wrapped rGO@AgNPs nanocomposite film (CS/rGO@AgNPs) was synthesized to achieve stabilizing and controlled-release of AgNPs. The results showed that the the CS/rGO@AgNPs film continued releasing AgNPs for up to 14 days, and the final release amount of silver nanoparticles was only about 1.9 %. More importantly, the nanocomposite film showed durable antibacterial effect and good antibacterial activity against E. coli and S. aureus, and they showed no toxicity to cells. Hence, the nanocomposite film has potential application as an effective and safe packaging material to prolong the shelf life of food products., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

In this study, a sulfate radical-advanced oxidation process (SR-AOP) was proposed by utilizing a bimetallic Co/Fe metal-organic frameworks/cellulose nanofiber membrane (Co/Fe bi-MOFs/CNF) as a catalyst for TBBPA degradation. Sulfate radicals (SO 4 -) and hydroxyl radicals (OH·) were generated through the activation of peroxymonosulfate (PMS) by Co/Fe bi-MOFs/CNF. Co/Fe bi-MOFs/CNF was prepared by a facile solvothermal method and vacuum filtration. CNF acted as a natural substrates material to relieve the agglomeration of loaded MOFs. Additionally the composite membranes was easily separated from the reaction solution. The properties of the composite materials and the main factors that influenced TBBPA degradation were elucidated in detail, along with the TBBPA degradation intermediates, recyclability, and TBBPA degradation pathway. Almost 100 % of TBBPA was degraded within 30 min under optimal conditions, and the rate constant was determined to be 0.764 min -1 . Furthermore, the degradation rate of the composite membrane was 60 % after 4 cycles., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Flexible paper-based nanocomposites dielectrics are of crucial importance in electrical insulation and advanced electrical power systems. In this work, a novel nanofibrillated cellulose/aramid fibrid (NFC/AF) composite was fabricated by vacuum-assisted filtration process. In order to improve the dielectric property of the composites, carboxylated nano-SiO 2 was chemically coated onto aramid fibrid via molecular self-assembly with the aid of phosphoric acid (PA) pretreatment and subsequent polyethyleneimine (PEI) functionalization. It was found that composites prepared by NFC and (PEI/SiO 2 )-modified AF (after crosslinking) ((PEI/SiO 2 )-AF) showed dense structure, which was mainly due to enhanced interfacial interaction between AF and NFC. Consequently, NFC/(PEI/SiO 2 )-AF paper-based composites showed better tensile toughness (∼6 % elongation at break) and mechanical strength (∼36.28 MPa), in comparison with NFC/AF. More importantly, the electrical insulation performance and thermal stability of the composites were significantly improved. Accordingly, this work provides a facile approach to fabricate high-performance dielectric composites especially for high-temperature electrical insulation applications., Competing Interests: Declaration of Competing Interest We declare that there is no conflict of interest., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

High strength and self-healing properties of hydrogels are of great interest in tissue engineering and biomedical fields. In this paper, nanocomposite hydrogels were prepared by freeze-thaw cycle method via fabricating physical cross-links into chemical-crosslinked formed polymer network. The properties of nanocomposite hydrogels were characterized by FTIR, XRD, SEM, rheological analysis, swelling analysis and mechanical test. The results showed that the electrostatic interaction between CNC and QAX and the high amount of PVA (20 wt%) were favorable to improve the mechanical properties of nanocomposite hydrogels, in which the maximum compressive strength and elongation at break of nanocomposite hydrogels were 1.56 MPa and 771 %, respectively. Prepared hydrogels achieved self-healing without any external stimuli at room temperature with the help of hydrogen bonds and the entanglement of long polymer chains, the healing efficiency was 37.03 % within 48 h. These hydrogels with high strength and self-healing properties will offer new insights for xylan application., Competing Interests: Declaration of Competing Interest The authors declare no conflict interest., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Polypyrrole (PPy) and cellulose nanofiber (CNF) based conducting composite films were synthesized using two new approaches, in-situ polymerization of pyrrole onto cellulose nanopaper (PPy/CNP) and polyvinyl alcohol coated cellulose nanopaper (PPy/PVA-CNP). Significant improvement in the conductivity, tensile strength, water resistance, and electromagnetic shielding effectiveness (SE) was observed for these composite films compared to commonly used in-situ nanofiber (ISF) approach, where PPy is coated on nanofibers prior to film preparation. Maximum improvement in conductivity, SE and tensile strength of PPy/PVA-CNP compared to ISF films was attributed to highly uniform and compact PPy coating and reduced porosity. SE of -23 dB (thickness upto 138.4 μm) and tensile strength of 103.8 MPa for PPy/PVA-CNP films are the highest values found in the literature for PPy and CNF based composite films at a comparable thickness. These new approaches could enable a scalable preparation of flexible conducting composite films with superior physical and electrical properties for EMI shielding applications., Competing Interests: Declaration of Competing Interest The authors declare no competing financial interest., (Published by Elsevier Ltd.)

Here, we designed a self-healing composite hydrogel with antioxidant and antibacterial activities by using cellulose nanofibrils (CNF) and tannic acid (TA) as functional additives. Excellent mechanical stability, moldability, stretchability and rapid self-healing ability without any external intervention were realized in one system due to the combined dynamic borate ester bonding between polyvinyl alcohol-borax (PB) and multi-hydrogen bonding between different components. The rheological measurements indicated the incorporation of CNF and TA to PB system substantially affected the viscoelasticity of hydrogels. The unique antioxidant and antibacterial properties were achieved due to the complexation of TA. These high performance multifunctional hydrogels opens a window for a broad application in the field of smart devices and surface engineering., (Copyright © 2019. Published by Elsevier Ltd.)

Facile strategy to construct a cellulose nanocomposite hydrogel with self-healing and biocompatible properties is reported by crosslinking dialdehyde cellulose nanocrystals with acylhydrazine-terminated polyethylene glycol via dynamic reversible acylhydrazone for the first time. The effects of process variables on gelation time, mechanical strength and self-healing efficiency of hydrogels were investigated. It was found that gelation time shortened from hours to seconds by adjusting gelator and catalyst concentration. Tensile and compressive strength of hydrogel could reach 141 K Pa and 580 K Pa at 20.1% gelator concentration, respectively. Interestingly, the as-prepared hydrogel presented excellent self-healing ability without additional stimuli whose healing efficiency was higher than 90% even at higher gelator concentration. Furthermore, Cytotoxicity test showed that cell viability almost reached 100% after culturing with hydrogel, which revealed the hydrogel was biocompatible., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Biodegradable, antimicrobial, and semiconducting cellulosic composite was synthesized by in-situ polymerization of polyaniline in the presence of cellulose. The cobalt ferrite nanoparticles (CFO-NPs) were added during the polymerization process to acquire this composite magnetic property. The CFO-NPs were prepared by sol-gel method with average particles size less than 50 nm. The nanocomposites were characterized by Fourier-transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM) and energy-dispersive X-ray (EDX). In addition, their magnetic, dielectric constant, dielectric loss, and conductivity behaviors were studied. The magnetization (M s ) and conductivity increased up to 3.7 emu/g and 3.5 × 10 -3  S/cm, respectively, with increasing CFO-NPs content. The prepared electromagnetic nanocomposite exhibits highly efficient biodegradability and antimicrobial activity against Escherichia coli, Bacillus subtilis, and Candida albicans. The antimicrobial activity increased with increasing CFO-NPs while the biodegradability decreased., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Cellulose nanofibrils (CNFs) have been widely used as the reinforcing agent. However, there is still a challenge to control the mechanical properties of CNFs-reinforced hydrogels by changing the environmental variables. Here, we demonstrated a thermo- and multi-pH-responsive CNFs-reinforced hydrogel containing lignin nanoparticles as the functional dynamic cross-linkers in the polymeric network. The elastic and viscous modulus of the hydrogel can be tailored: (i) the modulus increases upon increasing pH from 4 to 7, (ii) with pH further increasing from 7 to 9, the modulus decreases. The as prepared hydrogel also responded to the environment temperature, with the gelation at 26.4 °C. The significant differences in CNFs-reinforced hydrogel mechanics at various environment conditions are a direct result of the distinct stress-relaxation dynamics dictated by the dynamic hydrogen bonding and swelling/shrinking of lignin nanoparticles. This work also provides a new approach to design stimuli-responsive hydrogels., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

The aims of this study are to prepare quaternized xylan-Fe 2 O 3 (QX-Fe 2 O 3 ) core/shell nanocomposites and explore their potential application in the biomedical fields. γ-Fe 2 O 3 nanoparticles synthesized by a facile solvothermal process are coated with QX via reverse microemulsion method and further modified by polylysine (PLL) and folic acid (FA) to prepare PLL-QX-Fe 2 O 3 and FA-QX-Fe 2 O 3 nanoparticles. An obvious strong absorption of γ-Fe 2 O 3 at 580 cm -1 in the spectra of QX-Fe 2 O 3 is observed, the Fe element content of QX-Fe 2 O 3 is 30-75 μg/mL and the saturation magnetization of QX-Fe 2 O 3 nanoparticles is 1.49 emu/g. The γ-Fe 2 O 3 and QX-Fe 2 O 3 nanoparticles are of regular sphericity with diameter of 50-100 nm and 60-150 nm, respectively. The highest zeta potential of QX-Fe 2 O 3 nanoparticles is -41 mV, and the PLL-QX-Fe 2 O 3 nanoparticles have a positive potential with a maximum value of 45.2 mV. In addition, FA-QX-Fe 2 O 3 showed excellent performance in T 2 -weighted Magnetic Resonance (MR) imaging with an r 2 value of 190 mM -1 S -1 . Each nanocomposite has its own inherent properties, which contributes to its versatile utilization and application potential., (Copyright © 2018. Published by Elsevier Ltd.)

Bionanocomposites hydrogel based on conducting polymers were successfully fabricated from chitosan/polyacrylic acid/polypyrrole (CS/PAA/PPy) as well as the magnetite nanoparticle (Fe 3 O 4 -NPs) was prepared via co-precipitation method. In addition, different ratios of Fe 3 O 4 -NPs were added to the prepared bionanocomposites to enhance the antimicrobial and the electrical conductivity of the prepared conductive hydrogel. Furthermore, the morphology, the swelling percent, antimicrobial activity and the dielectric properties of the prepared conducting bionanocomposites hydrogel were investigated. The antibacterial activities of the experienced microbes were improved with the increasing the loading of Fe 3 O 4 -NPs in conducting Bio-nanocomposites hydrogel. Moreover, the DC-conductivity was examined and our resulted indicated that the DC-conductivity was enhanced by increasing the loadings of Fe 3 O 4 -NPs compared to that of the pure CS/PAA as well as CS/PAA/PPy., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Bacterial infection and uncontrolled bleeding are the major challenges facing the wound treatment. In order to solve these problems, we have devised a green nanocomposite hydrogel by introducing the aminated silver nanoparticles (Ag-NH 2 NPs) and gelatin (G) to carboxylated cellulose nanofibers (CNF). Interpenetrating polymeric network (IPN) was formed by interaction of multicomponent, leading to the non-covalent (dynamic ionic bridges) crosslinked hydrogel CNF/G/Ag. The produced hydrogel dressing with 0.5 mg/mL Ag-NH 2 NPs (CNF/G/Ag 0.5 ) demonstrated stronger mechanical, self-recovery, antibacterial properties, satisfactory hemostatic performance, and appropriate balance of fluids on the wound bed (2093.9 g/m 2 per day). More importantly, the wound healing model evaluation in vitro and in vivo of CNF/G/Ag 0.5 showed an outstanding biocompatibility (∼100% infected cell viability) and wound healing efficacy (∼90% healed and 83.3% survival after 14 days). Our study paved a highly promising approach to improve the performance of cellulose-based hydrogel dressing and would also be useful for developing ideal skin wound dressings by other green materials., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

It is of technical and economic importance to develop an effective cosmetic ingredient against skin aging through low-cost and facile production. This study developed a polymer/layered silicate nanocomposite as cosmetic ingredient against skin aging. Firstly, quaternized carboxymethyl chitosan (QCMC)/organic montmorillonite (OMMT) nanocomposite (QCOM) was fabricated via solution-induced intercalation. QCOM with different mass ratios of QCMC to OMMT were studied by various characterizations as well as moisture-adsorption and retention activities and UV-protection capacity. QCOM was then added into a cosmetic formulation to prepare a cosmetic cream. And the evaluation of its efficacy about skin care was conducted. The results showed that the optimal QCOM had better moisture-adsorption and retention behaviors than hyaluronic acid, and QCOM solution displayed good UV-protection ability. Furthermore, the QCOM-containing cosmetic cream meets the hygienic standard for cosmetics; it has negligible dermal irritation and a prominent moisture-retention efficacy on human stratum corneum., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Probiotic (Lactobacillus rhamnosus ATCC 9595) was encapsulated in alginate-CNC-lecithin microbeads to produce nutraceutical microcapsules. Addition of CNC and lecithin in alginate microbeads (ACL-1) improved the viability of L. rhamnosus during gastric passage and storage. The compression strength of the freeze-dried ACL-1 microbeads improved 40% compared to alginate microbeads alone. Swelling studies revealed that addition of CNC and lecithin in alginate microbeads decreased (around 47%) the gastric fluid absorption but increased the dissolution time by 20min compared to alginate microbeads (A-0). During transition through the gastric passage, the viability of L. rhamnosus in dried ACL-1 microbeads was increased 37% as compared to A-0 based beads. At 25 and 4°C storage conditions, the viability of L. rhamnosus encapsulated in ACL-1 microbeads decreased by 1.23 and 1.08 log respectively, whereas the encapsulation with A-0 microbeads exhibited a 3.17 and 1.93 log reduction respectively., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Quaternized carboxymethyl chitosan/organic rectorite (QCMC/OREC) nanocomposites were rapidly prepared by intercalating QCMC into the layer of OREC under microwave irradiation. And then copper-chelate QCMC/OREC (QCMC/OREC-Cu) nanocomposites were obtained by mixing QCMC/OREC with CuSO4 solution. XRD and TEM results indicated that QCMC/OREC nanocomposites were obtained and QCMC was dispersed in the interlayer of OREC. Besides, FT-IR results revealed that the hydrogen bonds and electrostatic interaction in QCMC/OREC-Cu were both stronger than those in QCMC/OREC because of introducing the Cu(2+). The thermogravimetric analysis showed that the thermal stability of QCMC/OREC-Cu nanocomposites was higher than QCMC and QCMC/OREC. Algae inhibition assay revealed that QCMC/OREC-Cu nanocomposites had stronger antifouling activity than original QCMC and QCMC/OREC. This work provides important basis for developing novel antifouling materials., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Incorporation of nanofillers into a polymeric matrix has received much attention as a route to reinforced polymer nanocomposites. In the present work, an environmentally friendly chitosan (CTS)/titanium dioxide (TiO2) nanocomposite coating was designed/prepared and subsequently employed for imparting antibacterium and improved mechanical properties to cellulosic paper via surface coating. Effect of TiO2 nanoparticle loadings on the rheological behavior of nanocomposite coatings was investigated. Surface application of CTS/TiO2 nanocomposite coatings to cellulosic paper was performed, and the antibacterial activity and mechanical properties of surface-coated cellulosic paper were examined. Results showed that the increased TiO2 nanoparticle loadings decreased the viscosity and dynamic viscoelasticity of the as-prepared coatings, and improved the antibacterial activity and mechanical properties of surface-coated cellulosic paper. The optimum loading of TiO2 nanoparticles was identified at 10%. This work suggested that CTS/TiO2 nanocomposite coatings may have the potential to be used as a promising antibacterial protective coating for paper packaging., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Polyaniline (PANI) with/without polystyrene (PS), was successfully manufactured in the occurrence of dispersed pulp fibers via the oxidative polymerization reaction of aniline monomer to produce conductive paper sheets containing PANI, PANI/PS composites. Additionally, sliver nitrate (Ag-NO3) was added by varied loadings to the oxidative polymerization of aniline monomer to provide sliver nanoparticles (Ag-NPs) emptied into the prepared paper sheets. The prepared paper sheets were examined using scanning electron microscopy (SEM), X-ray diffraction (XRD) and infrared spectroscopy (IR), the mechanical properties of the prepared paper sheets were evaluated. Moreover, the electrical conductivity and biological studies such as cellulases assay, Microorganism & culture condition and detection of the released of Ag-NPs were evaluated. Furthermore, the prepared paper sheets were displayed good antibacterial properties contrary to gram positive and gram negative bacteria. Consequently, the prepared paper sheet may be used as novel materials for packaging applications., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Quaternized chitosan/organic montmorillonite (QCS/OMMT) nanocomposites were synthesized under microwave irradiation. XRD and TEM analyses confirmed that QCS intercalated into the interlayer of OMMT and clay layers distributed uniformly in QCS matrix. QCS/OMMT nanocomposites were used as retention and drainage-aid agents in pulp suspension, during which the interface behavior of positively charged QCS/OMMT nanocomposites on negatively charged cellulosic substrate and CaCO3 substrate was investigated. With the addition of QCS/OMMT nanocomposites, the particle size of cellulosic substrate increased, while the beating degree and the total residual carbohydrate concentration decreased. The results indicated that QCS/OMMT nanocomposite made a difference in paper making process through the charge patch interaction. Moreover, QCS/OMMT nanocomposites had a strong interaction with CaCO3, which was significant in fiber fines retention and paper production. When the mass ratio of QCS to OMMT was 8:1, the QCS/OMMT nanocomposite demonstrated the strongest retention and drainage-aid effect., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

To obtain environmentally friendly antifouling agent, an effort was made to intercalate carboxymethyl chitosan into the interlayer of organic montmorillonite to prepare carboxymethyl chitosan/organic montmorillonite nanocomposites and their copper complexes. In comparison, carboxymethyl chitosan-copper complexes were also obtained. Their structures were characterized by X-ray diffaraction, transmittance electron microscopy and Fourier transform infrared, and their thermal behavior and antimicrobial activity were discussed. The results revealed that the interlayer distance of carboxymethyl chitosan/organic montmorillonite nanocomposites enlarged with the increasing mass ratio of carboxymethyl chitosan to organic montmorillonite, when the mass ratio was at 20:1, the layer spacing of carboxymethyl chitosan/organic montmorillonite nanocomposites reached the maximum of 3.68 nm. As compared to other samples, carboxymethyl chitosan/organic montmorillonite-copper nanocomposites showed much higher thermal stability and inhibitory activity against Escherichia coli, the lowest minimum inhibition concentration was only 0.0003125% (w/v). The study provides a new method to find novel antifouling agent., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

In this study the effects of chemical modification of cellulose nanofibers (CNFs) on the biodegradability and mechanical properties of reinforced thermoplastic starch (TPS) nanocomposites was evaluated. The CNFs were modified using acetic anhydride and the nanocomposites were fabricated by solution casting from corn starch with glycerol/water as the plasticizer and 10 wt% of either CNFs or acetylated CNFs (ACNFs). The morphology, water absorption (WA), water vapor permeability rate (WVP), tensile, dynamic mechanical analysis (DMA), and fungal degradation properties of the obtained nanocomposites were investigated. The results demonstrated that the addition of CNFs and ACNFs significantly enhanced the mechanical properties of the nanocomposites and reduced the WVP and WA of the TPS. The effects were more pronounced for the CNFs than the ACNFs. The DMA showed that the storage modulus was improved, especially for the CNFs/TPS nanocomposite. Compared with the neat TPS, the addition of nanofibers improved the degradation rate of the nanocomposite and particularly ACNFs reduced degradation rate of the nanocomposite toward fungal degradation., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Research on foamed nitrile rubber (NBR)/cellulose nanocrystals (CNs) nanocomposites is rarely found in the literatures. In this paper, CNs suspension and NBR latex was mixed to prepared the foamed NBR/CNs nanocomposites. We found that the CNs mainly located in the cell walls, effectively reinforcing the foamed NBR. The strong interaction between the CNs and NBR matrix restricted the mobility of NBR chains surrounding the CNs, hence increasing the crosslink density of the NBR matrix. CNs exhibited excellent reinforcement on the foamed NBR: a remarkable increase nearly 76% in the tensile strength of the foamed nanocomposites was achieved with a load of only 15 phr CNs. Enhanced mechanical properties make the foamed NBR/CNs nanocomposites a promising damping material for industrial applications with a potential to reduce the petroleum consumption., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Bionanocomposites were developed by casting/evaporation of wheat gluten (WG), cellulose nanocrystals (CNC), and TiO2 nanoparticles. The effect of addition of different percentages of CNC, and TiO2 on tensile strength (TS), Young's modulus and water sensitivity was studied. A significant improvement in the studied properties is observed when 7.5% CNC and 0.6% TiO2 is added to WG. WG/CNC 7.5%/0.6% TiO2 blend suspension was chosen to coat commercial packaging unbleached kraft paper sheets via 1, 2 and 3 coating layers. A significant enhancement of 56% and 53% in breaking length and burst index, respectively, was achieved for 3 layers coated paper. The antimicrobial activity of the coated papers, against Saccharomyces cervisiae, Gram-negative bacteria Escherichia coli and Gram-positive bacteria Staphylococcus aureus, was investigated and expressed in terms of reduction % of surviving number (CFU) of the tested organisms. More than 98.5% reduction in CFU was observed against the organisms compared to TiO2-free coated paper., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Sugarcane bagasse (SCB) was grafted with acrylamide (AAm) and glycidyl methacrylate (GMA) by chemical oxidation method. The effect of monomer/initiator molar ratio, reaction time, reaction temperature and material to liquor ratio on the degree of grafting was investigated. The optimum conditions for grafting were: monomer/initiator molar ratio 1 for AAm and 2 for GMA, reaction time 4h, reaction temperature 80°C and materials to liquor ratio 1:20. Silver nanoparticles (AgNPs) were prepared and characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). Ungrafted SCB, SCB-g-AAm and SCB-g-GMA were impregnated into silver (Ag) nanoparticles colloidal solution. The ungrafted SCB, grafted SCB and their nanocomposites with Ag nanoparticles were characterized by FT-IR spectroscopy, X-ray diffraction (XRD) and scanning electron microscopy (SEM). The grafted SCB/Ag nanoparticles exhibit better antimicrobial activity against Escherichia coli as the model Gram-negative bacteria, Staphylococcus aureus as the model Gram-positive bacteria and Aspergillus flavus and Candida albicans (yeasts) than ungrafted SCB/AgNPs., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

Microwave irradiation was used to intercalate quaternized carboxymethyl chitosan oligosaccharide (QCMCO) into the layer of rectorite (REC) to prepare QCMCO/REC (QCOR) nanocomposites in 70 min, which was much faster than conventional heating method of 48 h. The structures and morphology of QCOR nanocomposites were characterized by XRD, TEM, FT-IR and zeta potential analysis, the thermal behavior and antimicrobial activity of QCOR nanocomposites were also discussed. The results revealed that the interlayer distance of QCOR nanocomposites enlarged with the increase of QCMCO content, hydrogen bonding and electrostatic interaction between QCMCO and REC took place. As compared to QCMCO, the crystallinity of QCOR nanocomposites reduced, the thermal stability of QCOR nanocomposites improved, and the inhibitory activity of QCOR nanocomposites against microorganisms was stronger, the lowest minimum inhibition concentration was only 0.025% (w/v), the antimicrobial mechanism was discussed via TEM and SEM micrographs., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Cellulose nanocrystals have been prepared by acid hydrolysis of Luffa cylindrica fibers. The acid-resistant residue consisted of rod-like nanoparticles with an average length an diameter around 242 and 5.2nm, respectively (aspect ratio around 46). These cellulose nanocrystals have been used as a reinforcing phase for the processing of bio-nanocomposites using polycaprolactone (PCL) as matrix. To promote interfacial filler/matrix interactions the surface of cellulose nanocrystals was chemically modified with n-octadecyl isocyanate (C(18)H(37)NCO). Evidence of the grafting was supported by infrared spectroscopy and elemental analysis. X-ray diffraction analysis was used to confirm the integrity of cellulose nanocrystals after chemical modification. Both unmodified and chemically modified nanocrystals were used to prepare nanocomposites. The thermal properties of these materials were determined from differential scanning calorimetry and their mechanical behavior was evaluated in both the linear and non-linear range., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Exfoliated quaternized carboxymethyl chitosan/rectorite (QCMC/REC) nanocomposite was prepared via microwave irradiation method for 70 min, which was performed in only water without any additional plasticizer. XRD, TEM, AFM, SEM and FTIR results revealed that when the mass ratio of QCMC to REC was no less than 4:1, the silicate layers of REC were completely exfoliated in QCMC matrix and were homogenous with QCMC, the surface of QCMC/REC nanobiocomposite was very smooth; two types of interactions of hydrogen bond and electrostatic attraction existed in the QCMC/REC nanobiocomposite. Thermal analysis indicated that QCMC/REC nanobiocomposite had higher thermal stability than only QCMC. Therefore, the microwave irradiation method appears to be a promising tool for preparing exfoliated biopolymer/layered silicate nanocomposites at a mild condition., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

The preparation and characterization of bacterial cellulose (BC)/silica nanocomposites are presented in this paper. BC hydro-gel was immersed in an aqueous solution of tetraethoxysilane (TEOS). By pressing the treated BC matrices at 120 °C and 2 MPa, water-free translucent sheets were obtained. TEOS concentration (3, 5 and 7%) and press time (8, 10 and 12 min) were used as variable factors. These materials were characterized by different techniques, namely FE-SEM, FTIR, SEM, tensile strength and Young's modulus. All composites showed good dispersion of the fibers and strong adhesion between the fibers and the matrix. FE-SEM observations showed that the nano-scale silica was embedded between the voids and micro-fibrils of the BC matrix. Reflecting this structure, the maximum Young's modulus and tensile strength of dry BC/silica composites improved to 1.46 GPa and 113 MPa, respectively. The tensile strength and Young's modulus showed 35 and 18-fold increase (with 7% TEOS), respectively, while the same properties were reduced 15 and 10-fold with increase in press time from 8 to 12 min. FTIR results illustrated strong chemical interactions between the cellulose and silica phases. The optimum condition was obtained when the TEOS dosage and press time were 7% and 8 min, respectively., (Copyright © 2012 Elsevier Ltd. All rights reserved.)