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ABSTRACT: Conventional cellulosic paper, rendered electro‐conductive, may hold considerable promise for diversified applications in such areas as electro‐magnetic interference shielding and energy storage. Here, an electro‐conductive cellulosic paper was prepared by surface application of multi‐walled carbon nanotubes (MWCNTs)/polyaniline (PANI) nanocomposites onto a conventional base paper. MWCNTs/PANI nanocomposites were prepared by in situ polymerization of aniline with different contents of MWCNTs and used as electro‐conductive filler for the fabrication of electro‐conductive surface‐coated paper. The achieved MWCNTs/PANI nanocomposites exhibited a core‐shell structure, as evidenced by TEM. Effects of feeding ratios of MWCNTs on the rheological behavior of nanocomposite coatings, as well as the mechanical properties and electrical conductivity of surface‐coated paper were studied. Results revealed that the rheological behavior of the nanocomposite coatings showed strong dependence on the MWCNTs content. Moreover, both the electro‐conductivity and mechanical properties of surface‐coated paper were improved as a function of surface application of MWCNTs/PANI nanocomposites, particularly, in presence of an optimum content of MWCNTs. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46329. [ABSTRACT FROM AUTHOR]

Nanostructured composites built with microporous cellulose fibers and carbon nanotubes (CNTs) have potential impacts in the fields of energy storage, sensors, and flexible electronics. Few results have been shown for high mechanoelectrical sensitivity of CNT‐paper composite because of numerous current paths in the network. Here, CNT‐paper‐based nanostructured composite sensors whose sensitivities are generated by controlled tensile fracture of the composite are presented. Under uniaxial load, the cellulose fibers in the paper experience straightening, stiffening, and fracture. The cellulose fibers originally parallel to the tension are fractured while those inclined and perpendicular to the tension are reorganized to form crossbar junctions in the vicinity of a crack. The cross junctions exhibit resistive and capacitive sensitivity to the out‐of‐plane force by the compression of the junctions. Such piezoresistive and piezocapacitive sensitivities are characterized and evaluated for human behavior monitoring. [ABSTRACT FROM AUTHOR]

Well-dispersed Fe 3 O 4 nanoparticles (NPs) were synthesized by a co-precipitation method in the presence of cellulose nano-crystals (CNC) as the template. The thus prepared Fe 3 O 4 NPs were then used as a coating agent for the preparation of conductive paper. Fourier transform infrared spectroscopy (FTIR) results revealed that the Fe 3 O 4 NPs were immobilized on the CNC through interactions between the hydroxyl groups of CNC and Fe 3 O 4 . Scanning transmission electron microscopy (STEM) images showed that the Fe 3 O 4 NPs prepared in the presence of CNC can be dispersed in the CNC network, while the Fe 3 O 4 NPs prepared in the absence of CNC tended to aggregate in aqueous solutions. The conductivity of the Fe 3 O 4 NPs coated paper can reach to 0.0269 S/m at the coating amount of 14.75 g/m 2 Fe 3 O 4 /CNC nanocomposites. Therefore, the thus obtained coated paper can be potentially used as anti-static packaging material in the packaging field. [ABSTRACT FROM AUTHOR]

Cellulose nanofibers have been showing much greater potential to enhance the mechanical and physical properties of polymer-based composite materials. The purpose of this study is to extract the cellulose nanofibers from waste bio-resources; such as waste newspaper and paper sludge. The cellulosic raw materials were treated chemically and physically in order to extract individualized cellulose nanofiber. The combination of acid hydrolysis and following mechanical treatment resulted in the extraction of cellulose nanofibers having diameter of about 40 nm. In order to examine the reinforcing effect of the extracted cellulose nanofibers, fully biodegradable green nanocomposites were fabricated by composing polyvinyl alcohol (PVA) resin with the extracted cellulose nanofibers, and then the tensile tests were conducted. The results showed that the enhancement in mechanical properties was successfully obtained in the cellulose nanofiber/PVA green nanocomposites. [ABSTRACT FROM AUTHOR]

Highlights: [•] In this study we prepare Ag-NPs and Ag @ TiO2 composites as antibacterial nanomaterials. [•] Paper coated by PS nanocomposites containing Ag-NPs and Ag @ TiO2 composites. [•] We conclude that the prepared paper sheet characterize by SEM, EDAX and mechanical properties was evaluated. [•] Paper sheet coated by PS nanocomposites exhibited antimicrobial effect. [•] These Paper sheet can be used as food packaging materials. [ABSTRACT FROM AUTHOR]

Upon aging, paper documents and books become progressively damaged. Paper deacidification is a fundamental conservation intervention. In this study, we report on the use of nanoparticles of titanium dioxide (TiO2) and magnesium hydroxide (Mg(OH)2) associated with hydroxyethylcellulose (HEC) to inhibit acidification, photo-induced degradation, and biodeterioration of paper. With the aid of ultrasound, Mg(OH)2 nanoparticles with a narrow size distribution can be obtained through homogeneous precipitation in water. Furthermore, to demonstrate the efficacy of the nanocomposite and the performance of treated and untreated paper, photo- and thermal-induced degradation is discussed. The results show that using the controlled double-jet precipitation (CDJP) it is possible to synthesize Mg(OH)2 particles with a narrow size distribution (18-87 nm). The nanocomposite of Mg(OH)2-TiO2-HEC increases the durability of paper by imparting fungal growth resistance (D= 34.6 mm), moderate alkalinity (pH = 8.4), mechanical reinforcement (from 817-896 N/m), and UV protection. Additionally, there is a slight color difference (ΔE* = 0.8) between the treated and untreated paper. Both photodegradation and thermal degradation indicate that the paper treated with this nanocomposite (Mg(OH)2-TiO-HEC) has increased stability. [ABSTRACT FROM AUTHOR]

Abstract: In this work, we demonstrated a novel paper-based mediator-less and compartment-less biofuel cell (BFC) with small size (1.5cm×1.5cm). Ionic liquid functionalized carbon nanotubes (CNTs-IL) nanocomposite was used as support for both stably confining the anodic biocatalyst (i.e., NAD+-dependent glucose dehydrogenase, GDH) for glucose electrooxidation and for facilitating direct electrochemistry of the cathodic biocatalyst (i.e., bilirubin oxidase, BOD) for O2 electroreduction. Such BFC provided a simple approach to fabricate low-cost and portable power devices on small-size paper, which can harvest energy from a wide range of commercial beverages containing glucose (e.g., Nescafe instant coffee, Maidong vitamin water, Watermelon fresh juice, and Minute Maid grape juice). These made the low-cost paper-based biodevice potential for broad energy applications. [Copyright &y& Elsevier]

This review provides a brief overview of the recent research efforts carried out at the CICECO laboratory of the University of Aveiro on novel materials based on chitosan within the background of previous investigations of similar counterparts. Most of this work is devoted to different modes of combining chitosans of various molecular weights and degrees of deacetylation (including appropriately modified chitosans providing either fluorescent properties or water solubility) with cellulose fibres of various sizes (standard to nanosize), morphologies (conventional papers, nanofibrillated or bacterial strands) and assemblies (composites or paper coating and impregnation). Additionally, the radical transformation of chitin and chitosan low-quality residues into viscous polyols by a straightforward oxypropylation is also discussed. The results of these investigations show the remarkable potential of chitosan as a source of promising blends and composites, among other novel materials. Copyright © 2011 Society of Chemical Industry The incorporation of cellulose nanofibres into chitosan films improves the mechanical properties of the films while preserving their transparency. The incorporation of chitosan into paper sheets improves their printability, among other positive features. [ABSTRACT FROM AUTHOR]

A new method for making superhydrophobic (SH) paper based on spraying a nanocomposite film is developed. Furthermore, manipulating the wetting characteristics of SH paper has been demonstrated through a new method, i.e.printing solid grey patterns of different intensities with simple printing technology (home or office grade ink-jet and laser printers). It has been found that for a range of ink intensities (0–85%), water drop mobility can be changed at a different rate (almost independently) from repellency. The repellency of water decreases minimally up to 85% ink intensity with a sharp decrease up to 100% ink intensity. Drop mobility remains constant up to 30% ink intensity with a steady decrease up to 100% ink intensity. It was observed that using ink-jet or laser printing would yield different results for the change of mobility or repellency with higher amounts of ink/toner used. Being able to achieve almost independent control of water drop mobility over water drop repellency on SH paper would allow inexpensive lab-on-paper devices to be used for sampling, mixing and transport of liquids. [ABSTRACT FROM AUTHOR]

We present theory for the shrinkage on drying of the cross-sectional area of cellulosic fibres and show that this depends on their initial moisture content only. For the linear shrinkage of cross-sectional dimensions, an additional parameter is required, which we estimate from comparison of the theory with experimental data from the literature. We proceed to combine our model of fibre shrinkage with probabilistic theory for fibre contacts in random fibrous networks to obtain a model for the unrestrained shrinkage of isotropic paper sheets. The expression obtained depends only on the moisture content of fibres and the extent of inter-fibre contact and exhibits good agreement with experimental data for laboratory-formed paper sheets. The results have relevance to the commercial manufacture of paper and potential for application to the study of cellulose nano-composites. [ABSTRACT FROM AUTHOR]