The Potential of NanoCellulose in the Packaging Field: A Review

Nanocellulose has potential applications across several industrial sectors and allows the development of innovative materials, as well as the enhancement of conventional materials properties. The nanocellulose particles can be utilized as fillers, in composites manufacture, as coating and as self‐standing thin films, achieving always very interesting and promising properties. Very few of the several reviews that recently appeared on this topic in the scientific literature, however, summarized the potential of cellulose in nanoform specifically for the packaging field rather focusing on different aspects, ranging from the chemistry and the morphology of nanocellulose particles to the preparation methods, the industrial applications and the patents released. In the present review, the remarkable chemical and physical properties of nanocellulose are introduced and discussed with specific reference to the packaging needs. First, the cellulose resources and structure are introduced, then the process methods to reach the nanoscale, the corresponding morphologies and nomenclatures are summarized, mentioning also the possible chemical modifications of nanocellulose and, finally, its practical and potential applications for packaging materials, especially food packaging materials, are tentatively proposed and discussed. Although the review might not cover every aspect on nanocellulose, yet the key points, particularly those related to safety and biodegradability issues, are regarded and considered. Copyright © 2015 John Wiley & Sons, Ltd.     

Current international research into cellulose as a functional nanomaterial for advanced applications

This review paper provides a recent overview of current international research that is being conducted into the functional properties of cellulose as a nanomaterial. A particular emphasis is placed on fundamental and applied research that is being undertaken to generate applications, which are now becoming a real prospect given the developments in the field over the last 20 years. A short introduction covers the context of the work, and definitions of the different forms of cellulose nanomaterials (CNMs) that are most widely studied. We also address the terminology used for CNMs, suggesting a standard way to classify these materials. The reviews are separated out into theme areas, namely healthcare, water purification, biocomposites, and energy. Each section contains a short review of the field within the theme and summarizes recent work being undertaken by the groups represented. Topics that are covered include cellulose nanocrystals for directed growth of tissues, bacterial cellulose in healthcare, nanocellulose for drug delivery, nanocellulose for water purification, nanocellulose for thermoplastic composites, nanocellulose for structurally colored materials, transparent wood biocomposites, supercapacitors and batteries.

     

Nanocellulose as a natural source for groundbreaking applications in materials science: Today’s state

Nanocelluloses are natural materials with at least one dimension in the nano-scale. They combine important cellulose properties with the features of nanomaterials and open new horizons for materials science and its applications. The field of nanocellulose materials is subdivided into three domains: biotechnologically produced bacterial nanocellulose hydrogels, mechanically delaminated cellulose nanofibers, and hydrolytically extracted cellulose nanocrystals. This review article describes today’s state regarding the production, structural details, physicochemical properties, and innovative applications of these nanocelluloses. Promising technical applications including gels/foams, thickeners/stabilizers as well as reinforcing agents have been proposed and research from last five years indicates new potential for groundbreaking innovations in the areas of cosmetic products, wound dressings, drug carriers, medical implants, tissue engineering, food and composites. The current state of worldwide commercialization and the challenge of reducing nanocellulose production costs are also discussed.     

In situ processing of cellulose nanocomposites

Nanocellulose has gained attention in recent times due to their light weight, high strength, stiffness, biodegradability and renewability. Natural fibres have been used as reinforcement in composites for past many years, but the use of nanocellulose as reinforcement in composites is relatively new. The main challenges of preparing nanocellulose based composites include (i) generation of nanocellulose from natural resources, (ii) production in larger scale, (iii) enhancing compatibility with hydrophobic polymers, and (iv) achieving uniform dispersion in polymer matrices. These challenges have encouraged researchers to innovate efficient processes and techniques to utilise the maximum benefit of such green nanoscopic materials. In situ fabrication of cellulose nanocomposites is one such technique of achieving uniform nanocellulose dispersion in polymer matrices and obtaining a stronger filler/matrix interface. This review summarises the recent progress in the field of in situ processing of cellulose nanocomposites.     

纳米纤维素在气体阻隔包装材料中的应用进展

目的介绍纳米纤维素在包装中的应用与国内外的研究现状,阐述纳米纤维素在改善包装材料气体阻隔性能方面的作用机理、作用方式及作用效果,并对纳米纤维素在气体包装材料领域中的应用前景进行展望。方法归纳整理国内外文献,简单介绍纳米纤维素的基本性能和制备,以及纳米纤维素复合材料的制备方法,并重点整理分析纳米纤维素复合材料在阻隔包装材料领域的应用与进展。结果纳米纤维素具有来源广泛、可降解、可再生以及高结晶度等优良特性,在包装材料中加入纳米纤维素可以显著提高包装材料的气体阻隔性能。结论随着对纳米纤维素研究的不断深入,纳米纤维素在气体阻隔包装材料中的应用会越来越广泛。     

Extraction of cellulose nanocrystals from plant sources for application as reinforcing agent in polymers

In the last few decades, the usages of plant sources-based stiff fillers as reinforcement material in polymer composites have attracted significant interests of researchers. The crystalline part of the semicrystalline cellulose chains as found in the plant cell walls represents the most highly potential reinforcing agents for polymer. This review systematically covers the extraction of nano-sized cellulose crystals from plant cell wall which involving the applications of several highly effective techniques. The topic about the derivation of products functionality at each stage as well as their influences on the final reinforcing capability is also covered. Apart from these, a detailed overview of current knowledge on the surface modification of nanocellulose has been provided also. Inasmuch, this paper is desired to encourage the emergence of preparation of cellulose derivative nanocrystals with controlled morphology, structure and properties, so that enable positive development of biocompatible, renewable and sustainable reinforcing materials for polymer composites field.     

Ultrasensitive Physical,Bio, and Chemical Sensors Derived from 1‐, 2‐, and 3‐D Nanocellulosic Materials

Sensors are of increasing interest since they can be applied to daily life in different areas from various industrial sectors. As a natural nanomaterial, nanocellulose plays a vital role in the development of novel sensors, particularly in the context of constructing multidimensional architectures. This review summarizes the utilization of nanocellulose including cellulose nanofibers, cellulose nanocrystals, and bacterial cellulose for sensor design, mainly focusing on the influence of nanocellulose on the sensing performance of these sensors. Special attention is paid to nanocellulose in different forms (1D, 2D, and 3D) to highlight the impact of nanocellulose constructed structures. The aim is to provide a critical review on the most recent progress (especially after 2017) related to nanocellulose‐containing sensors, since there are significantly increasing research activities in this area. Moreover, the outlook for the development of nanocellulose‐containing sensors is also provided at the end of this work.     

Thermal conductivity analysis and applications of nanocellulose materials

Abstract

In this review, we summarize the recent progress in thermal conductivity analysis of nanocellulose materials called cellulose nanopapers, and compare them with polymeric materials, including neat polymers, composites, and traditional paper. It is important to individually measure the in-plane and through-plane heat-conducting properties of two-dimensional planar materials, so steady-state and non-equilibrium methods, in particular the laser spot periodic heating radiation thermometry method, are reviewed. The structural dependency of cellulose nanopaper on thermal conduction is described in terms of the crystallite size effect, fibre orientation, and interfacial thermal resistance between fibres and small pores. The novel applications of cellulose as thermally conductive transparent materials and thermal-guiding materials are also discussed.     

Beneficiation of pulp and paper mill sludge: production and characterisation of functionalised crystalline nanocellulose

The beneficiation of sludge from pulp and paper mills to produce high-value products such as crystalline nanocellulose will alleviate the challenges associated with conventional methods of sludge disposal, such as landfilling and incineration. In addition, the use of sludge will reduce the consumption of fresh raw materials in the synthesis of nanocellulose which is usually produced from high-purity cellulose pulps. In this study, fibres were cleaned and separated from sludge and then converted to crystalline nanocellulose using ammonium persulphate under optimised oxidative conditions. To extend potential applications of the crystalline nanocellulose produced, the crystalline nanocellulose was functionalised with zinc oxide, silver and hydroxyapatite to prepare crystalline nanocellulose-zinc oxide, crystalline nanocellulose-silver and crystalline nanocellulose-hydroxyapatite nano- and micro-composites powders using the sol–gel process. Transmission electron microscopy, field-emission scanning electron microscopy, X-ray diffraction and thermo-gravimetric analysis were used to investigate the properties of crystalline nanocellulose and functionalised crystalline nanocellulose. The transmission electron microscope and field-emission scanning electron microscope coupled with energy-dispersive X-ray spectroscopy confirmed the synthesis of crystalline nanocellulose, and inorganic nanoparticles. Functionalised samples (crystalline nanocellulose-zinc oxide, crystalline nanocellulose-silver and crystalline nanocellulose-hydroxyapatite) showed better thermal stability than pure crystalline nanocellulose. This implies that the modified inorganic crystalline nanocellulose composites could be used in applications where thermal stability is desirable. The cost of production is economically viable as the raw material cost is cheaper compared to the use of wood pulp.     

纳米纤维素基材料在柔性电子器件中的应用

目的 由于纳米纤维素基材料良好的柔韧性、热力学性能和高透明度,近年来在柔性电子产品中引起越来越多的关注。通过综述该领域的研究进展,将有助于研究人员更高效地开展研究。方法 综述3类纳米纤维素的制备方法及将纳米纤维素基材料应用在柔性电子产品中的研究进展。分别阐述纳米纤维素基材料应用于器件柔性衬底及绝缘材料的研究实例,并讨论纳米纤维素在各种应用方向中的优势以及存在的问题,最后对材料的未来应用前景进行展望。结论 纳米纤维素是天然纤维素与纳米技术结合的产物,可主要划分为纤维素纳米纤丝、纤维素纳米晶以及细菌纤维素3类。近年来,纳米纤维素基材料作为电子器件柔性衬底、绝缘材料等研究均有许多成果问世。虽然纳米纤维素基电子器件的开发还主要停留在实验室阶段,但是与传统的石油化工产品相比,纳米纤维素具有原材料丰富、环保可降解等优点。对纳米纤维素基新型材料的开发利用,有助于解决人类社会中日益严重的电子垃圾问题。     

Microstructural and Nano‐Mechanical Characterisation of Multicomponent Composites Nanocrystalline Matrix

Multicomponent, Ti‐based, in situ formed composites with a nanocrystalline matrix are a promising new type of material for structural applications. The materials exhibit an excellent combination of mechanical properties resulting from the composite microstructure. This paper contains a detailed introduction to such materials and a review of the most recent developments in the specific areas of microstructural and nano‐mechanical characterization.     

An overview of mechanical properties and durability of glass-fibre reinforced recycled mixed plastic waste composites

In recent years, there has been an increasing interest in seeking the potential applications of recycled mixed plastic wastes in building and construction sectors to relieve the pressure on landfills. This paper presents the recent developments and applications of composite materials made from recycled mixed plastics and glass fibre. Some of the first uses for such composites are as an alternative to non-load bearing applications like park benches and picnic tables. With its inherent resistance to rot and insect attack, these composites can in fact be used as a replacement for chemically treated woods in various larger-scale outdoor applications such as railroad crossties and bridges. However, the properties of the structural components made from recycled mixed plastics are not well understood. Information on the behaviour of such composites under applied loading and at different environmental conditions such as elevated temperature and ultraviolet rays are crucial for the utilisation of recycled mixed plastic materials in construction. This paper presents an overview of the mechanical properties and durability of recycled mixed plastic waste composites. The paper identifies research needs critical in the effective design and utilisation of these composite materials in civil engineering and construction.     

Nature-Inspired Emerging Chiral Liquid Crystal Nanostructures: From Molecular Self-Assembly to DNA Mesophase and Nanocolloids

Liquid crystals (LCs) are omnipresent in living matter, whose chirality is an elegant and distinct feature in certain plant tissues, the cuticles of crabs, beetles, arthropods, and beyond. Taking inspiration from nature, researchers have recently devoted extensive efforts toward developing chiral liquid crystalline materials with self-organized nanostructures and exploring their potential applications in diverse fields ranging from dynamic photonics to energy and safety issues. In this review, an account on the state of the art of emerging chiral liquid crystalline nanostructured materials and their technological applications is provided. First, an overview on the significance of chiral liquid crystalline architectures in various living systems is given. Then, the recent significant progress in different chiral liquid crystalline systems including thermotropic LCs (cholesteric LCs, cubic blue phases, achiral bent-core LCs, etc.) and lyotropic LCs (DNA LCs, nanocellulose LCs, and graphene oxide LCs) is showcased. The review concludes with a perspective on the future scope, opportunities, and challenges in these truly advanced functional soft materials and their promising applications.     

Multifunctional nanoparticles, nanocages and degradable polymers as a potential novel generation of non-invasive molecular and cellular imaging systems

In recent years, polymeric scaffolds have been used in several biomedical applications for delivery of drugs or other biologically relevant molecules. Polymeric nanostructures display different (and in some cases more powerful) properties respect to bulk materials. This, lead academic researchers and industry to cooperate in developing pioneering nanostructured materials for industrial and biomedical applications. Moreover, the preparation and use of systems with multiple (multifunctional) properties (i.e., bioconjugation with superparamagnetic, fluorescent or targeting molecules) is positioned to become a viable and innovative tool for application in several clinical fields. Other nanostructured systems like nanocages and degradable nanoparticles, are emerging as potential innovative systems that could be exploited as multifunctional delivery vectors. This brief critical review is aimed at collecting and discussing some recent patents dealing with the preparation and use of multifunctional nanoparticles, nanocages and degradable nanoparticles in biomedicine and non-invasive bioimaging applications. Perspectives for a potential use of these multifunctional nanosystems in pediatries have been also discussed.     

纳米纤维素增强淀粉食品包装材料的研究进展

目的 为了解决纯淀粉材料力学性能低、脆性大等缺点,探索纳米纤维素对淀粉膜材料的影响,为食品包装材料领域和替代传统石油基的高分子材料方向提供新的思路。方法 通过跟进国内外纳米纤维增强淀粉相关研究和应用进展,概括3种纳米纤维素的性能,介绍淀粉食品包装材料未来将面临的挑战和机遇,重点分析纳米纤维素对淀粉膜性能的影响。结论 纤维素纳米纤维（CNF）、纤维素纳米晶（CNC）和微晶纤维素（MCC）对淀粉进行增强后,淀粉复合材料的力学性能、阻隔性能和热学性能均得到改善,纳米纤维素增强淀粉食品包装材料在未来食品包装领域将得到扩展。     

Wood‐Based Nanotechnologies toward Sustainability

With over 30% global land coverage, the forest is one of nature's most generous gifts to human beings, providing shelters and materials for all living beings. Apart from being sustainable, renewable, and biodegradable, wood and its derivative materials are also extremely fascinating from a materials aspect, with numerous advantages including porous and hierarchical structure, excellent mechanical performance, and versatile chemistry. Here, strategies for designing novel wood‐based materials via advanced nanotechnologies are summarized, including both the controllable bottom‐up assembly from the highly crystalline nanocellulose building block and the more efficient top‐down approaches directly from wood. Beyond material design, recent advances regarding the sustainable applications of these novel wood‐based materials are also presented, focusing on areas that are traditionally dominated by man‐made nonrenewable materials such as plastic, glass, and metals, as well as more advanced applications in the areas of energy storage, wastewater treatment and solar‐steam‐assisted desalination. With all recent progress pertaining to materials' design and sustainable applications presented, a vision for the future engineering of wood‐based materials to promote continuous and healthy progress toward true sustainability is outlined.     

Review of recent achievements in self-healing conductive materials and their applications

Self-healing materials have attracted increasing attention because of their wide range of applications. It can be expected to offer obvious advantages in conductive materials with self-healing properties, which are regarded as promising candidates for the fabrication of self-healing electronics, energy storage devices, sensors, anticorrosive coating and conductive adhesives. In this review, we focused on recent efforts to develop self-healing conductive composites including their preparation methods, properties and applications. The self-healing conductive materials were presented based on different conductive mediums, such as metal, carbon, conductive polymer, ionic liquids. In addition, their novel applications of the self-healing conductive materials in conductive coatings, energy storage devices and sensors are highlighted. Finally, the future challenges of conductive materials with self-healing properties are proposed.     

Composite materials for aerospace applications

Fibre-reinforced polymer composite materials are fast gaining ground as preferred materials for construction of aircraft and spacecraft. In particular, their use as primary structural materials in recent years in several technology-demonstrator front-line aerospace projects world-wide has provided confidence leading to their acceptance as prime materials for aerospace vehicles. This paper gives a review of some of these developments with a discussion of the problems with the present generation composites and prospects for further developments. Although several applications in the aerospace sector are mentioned, the emphasis of the review is on applications of composites as structural materials where they have seen a significant growth in usage. The focus of the paper is especially on the developments on the Indian aerospace scene. A brief review of composites usage in aerospace sector is first given. The nature of composite materials behaviour and special problems in designing and working with them are then highlighted. The issues discussed relate to the impact damage and damage tolerance in general, environmental degradation and long-term durability. Current solutions are briefly described and the scope for new developments is outlined. In the end, some directions for future work are given.     

Bioinspired design toward nanocellulose-based materials

Nature provides lots of inspiration for material and structural design for various applications. Deriving design principles from the investigation of nature can provide a rich source of inspiration for the development of multifunctional materials. The bioinspired design templates mainly include mussels, nacre, and various plant species. As a sustainable and renewable feedstock, nanocellulose can be used to fabricate advanced materials with multifunctional properties through bioinspired designs. However, challenges and opportunities remain for realizing the full potential in the design of novel materials. This article reviewed recent development in the bioinspired nanocellulose based materials and their application. This article summarizes the functions (e.g., surface wetting) and applications (e.g., composite) of bioinspired nanocellulose-based materials. The bioinspired design templates are discussed along with strategies, advantages, and challenges to the development of synthetic mimics. Additionally, mechanisms and processes (e.g., chemical modification, self-assembly) leading to biomimetic design are discussed. Finally, future research directions and opportunities of bioinspired nanocellulose-based materials are highlighted.     

Review of nanocarbon-engineered multifunctional cementitious composites

As structural materials, cementitious materials are quasi-brittle and susceptible to cracking, and have no functional properties. Nanotechnology is introduced into cementitious materials to address these issues. Nano materials, especially nano carbon materials (NCMs) were found to be able to improve/modify the mechanical property, durability and functional properties of cementitious materials due to their excellent intrinsic properties and composite effects. Here, this review focuses on the recent progress of fabrication, properties, and structural applications of high-performance and multifunctional cementitious composites with NCMs including carbon nanofibers, carbon nanotubes and nano graphite platelets. The improvement/modification mechanisms of these NCMs to composites are also discussed.