Bionanocomposites for Packaging Applications

There is an increasing concern on the environmental issues related to petroleum-based plastics as packaging materials. Therefore, the interest for biodegradable packaging materials from renewable sources (biopolymers) has been increased steadily, particularly for the utilization in short-term packaging and throwaway applications. However, biopolymers have usually low barrier and mechanical characteristics with poor processability resulting in limitations for their scalable production and industrial use. To overcome these limitations, bio-nanocomposites with enhanced packaging characteristics such as mechanical strength, barrier properties against gases and water, and optical clarity have been developed. Moreover, bioactive ingredients can be added to give the targeted functional properties to the subsequent packaging materials. This chapter reviews distinctive sorts of new biobased nanocomposite materials, for example, biodegradable and edible nanocomposite films, and their commercial applications as packaging materials, and relevant regulations.

Packaging technology is mainly dealing with the safety storage and hygienic handling of daily needs and undergoes in continuous modification with time as per the choice of the consumers. With the ever-increasing market race, psychological aspect of the consumer behavior is also reflected in the packaging technology. For easy production and low cost of synthetic plastic materials, it has won the prime interest in packaging field. But, environmental issues lead the system to run behind the fabrication of eco-friendly bionanocomposites with incorporation of nanomaterials in renewable, biodegradable polymers in order to obtain bionanocomposites with improved fire retardant, oxygen barrier, thermal and mechanical properties. This chapter focusses some important basics of polymer-based bionanocomposites for packaging applications. The mechanical, fare retardant, thermal and gas barrier properties are improved substantially with incorporation of nanomaterials with biopolymers. Herein, the commercial, physiological and safety aspects of packaging materials are also discussed for the promotion of polymer-based nanocomposite as a future smart material for packaging products.

This chapter provides a broad overview of bionanocomposite film prepared from various biodegradable polymers reinforced with nanocellulose. In nature, biodegradable polymer exhibits relatively weaker properties than the synthetic polymers. Incorporation of cellulose into the biopolymer matrix has improved the mechanical, thermal, and barrier properties of the resulting biopolymer film significantly. This achievement has encouraged their application as packaging material. Since they have a huge potential in the future, further investigation of this composite material is crucial.

Nanohybrid active fillers are gaining interest from basic and applied research, due to their potential to provide quality and safety benefits. Great attention has been devoted in the last decade to the hybrid organic–inorganic systems, in particular to those in which inorganic materials are dispersed at a nanometric level in polymeric matrices. This review presents some important examples of the most used inorganic nanometric fillers, with antimicrobial activity for potential active packaging applications. Particular emphasis is given to biodegradable polymer matrices such as aliphatic polyesters, polysaccharides, proteins, and their blends. As food contact materials, they present the possibility of being carriers of different additives, such as antioxidant, antimicrobial, nutraceuticals, and flavoring agents. Current regulation issues are also reported and discussed and possible trends and perspectives in the food contact field shortly commented.

The use of biodegradable polymers for food packaging material is favorable due to its ability to degrade after use. Nevertheless, the real application of the polymers is still limited due to its poor physical properties. Polylactic acid (PLA) is one of the biodegradable polymers commonly used for packaging. Recently, there have been reports on the use of nanocellulose as filler in polylactic acid (PLA) for improving the mechanical properties of PLA; however, it has limitation in which non-uniform dispersion of nanocellulose is formed within the polymer during melt-blending. Uniform dispersion can be obtained through solvent casting method; nevertheless, it is not industrially applicable. In this study, a one-pot process was developed where nanofibrillation of cellulose and subsequently melt-blending of the nanocellulose with PLA were conducted in a twin-screw extruder. Results showed that nanocomposite reinforced with 3 and 5 wt% cellulose nanofiber (CNF) exhibited higher tensile strength and Young’s modulus compared to neat PLA. Crystallinity of the polymer increased by 43% with the addition of 5 wt% CNF. Meanwhile, wettability of the polymer was also improved as seen by the reduction in contact angle value. Results obtained exhibited the potential of the composite films to be used in packaging material, especially for high respiration products.

Concerns on environmental waste problems caused by non-biodegradable petrochemical-based plastic packaging materials as well as the consumers demand for high-quality food products have caused an increasing interest in developing biodegradable packaging materials like polysaccharides. Out of these polysaccharides, Chitosan has created its greater interest due to non-toxic, antibacterial behaviour, film-forming abilities and low permeability to oxygen, poor thermal and mechanical properties restricted its wide spread applications for packaging. However, reinforcement of various nanostructured materials shall increase the mechanical, thermal and gas barrier properties of chitosan without disturbing the biodegradable behaviour. This chapter summarizes different characterization techniques such as Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), Scanning electron microscopy (SEM), Transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS) of chitosan-based bionanocomposites. For keeping on the packaging applications of the materials, the important properties such as thermal and mechanical gas barrier and antimicrobial properties of chitosan-based bionanocomposites are discussed. The main focus of this chapter is to establish the packaging applications of chitosan-based bionanocomposites.

Non-biodegradable petroleum-based plastics are still the most dominant material used by the food industry for packaging applications. Consequently, the widespread usage of these conventional plastics has led to serious negative environmental impacts. Numerous studies were conducted over the years to substitute these packaging plastics with eco-friendly materials in order to arrest the ongoing plastic waste disposal problems. Against this background, the current chapter presents a review of recent works on sugar palm starch-based films and different modification techniques employed to improve their performance as effective biopackaging material.

Recent interest in environmentally friendly bio-based polymers coupled with an increased food safety awareness has resulted in various packaging technology advances, including the incorporation of different kinds of nanofillers into biodegradable biopolymers to improve their overall properties for improving shelf life and preventing microbial growth. Among the different nanofillers that have recently emerged, graphene’s invention has catalyzed a multitude of novel material applications in different fields. Graphene has functionalized different biopolymers and has improved their mechanical, thermal, electrical, as well as, gas, and water vapor barrier properties, for potentially replacing petrochemical-based packaging materials that pose a great threat to the environment. The objective of this chapter is to provide comprehensive understanding of the different types of nanoreinforcement that are available for biodegradable packaging application, especially focusing on graphene oxide (GO), a graphene derivative nanofiller that is being extensively studied for packaging reinforcement. This chapter aims to draw a clear picture of synthesis and chemistry of bonding between graphene derivatives and biodegradable biopolymers suitable for packaging applications, like starch, cellulose, poly(lactic acid), and others. The methodology behind the chemical and physical changes during synthesis will be discussed, based on different spectroscopic characterization techniques, and the influence of chemical changes on resulting properties will also be highlighted. This chapter will also briefly go over other nanomaterials like clay, cellulose nanofibers, starch nanocrystals, and their usage in different biopolymers for packaging application. This will help to explain the synergy resulting from addition of nanomaterials, the use of different characterization techniques as well as the improvement in different properties.

In the present work, cellulose nanocomposites dispersed with copper nanoparticles (CuNPs) were prepared using CuSO₄·5H₂O as the source and Cassia alata leaf extract as the reducing agent. These nanocomposites were prepared by regeneration method using ethanol as the coagulant. The morphology of generated CuNPs was viewed by SEM and TEM. The cellulose/CuNPs composite films showed good antibacterial activity against E-coil. The interaction between cellulose matrix and CuNPs was examined by FTIR and XRD. The changes in the thermal and tensile properties were examined with TGA and tensile tests. All these studies revealed that cellulose/CuNPs composites have enhanced thermal stability, tensile strength by the addition of CuNPs. These biodegradable cellulose/CuNPs composites films can be used for packaging and biomedical applications.

The use of plastic packaging material goes on increasing due to its high mechanical, oxygen barrier, and water vapor barrier properties. However, it lacks biodegradability and environmental compatibility. Biopolymers like polysaccharides can be used to solve such environmental hazards due to their non-biodegradability and toxicity. Besides these advantages, polysaccharides also have some disadvantages such as poor mechanical properties and low resistance to water. Hence, nanomaterials are promising reinforcing candidates to enhance the mechanical, thermal, and gas barrier properties without hampering their biodegradable and non-toxic characters. In the present chapter, different explanations are included to improve the properties responsible for packaging applications of these biopolymers. The focus of this chapter highlights the use of various polysaccharides-based bionanocomposites for food packaging applications. The combining study of different plant- and animal-based bionanocomposites in one chapter may explore a new idea for eco-friendly and future materials for food packaging.

The ever-growing demand for the development of high-performance packaging films and the equally growing need to protect our environment has led to intense research in the manufacture of eco-friendly films with good mechanical and barrier properties. Rice husk (RH)/montmorillonite (MMT) filled and maleic anhydride-grafted polyethylene (MAPE) compatibilized LDPE films were prepared by extrusion blown film. MAPE, RH and MMT were used in various loading to study their effect on the mechanical, oxygen barrier and morphological properties. Results revealed that MAPE helped LDPE chains to delaminate MMT platelets and distribute RH/MMT uniformly in the LDPE matrix. In addition, mechanical and barrier properties of nanocomposite films prepared by MAPE as compatibilizer are better than those without compatibilizer. Increasing RH content in RH/MMT filler deteriorated mechanical and barrier properties. Increasing MMT content into RH/MMT filler-filled LDPE nanocomposite films improved the tensile and barrier properties significantly, and the films containing 4 phc MMT, 3wt% RH and 6wt% MAPE are the optimum formulation as evidenced by mechanical properties and oxygen permeability. The unique combination of mechanical properties and oxygen permeability for RH/MMT filler-filled LDPE composite films shows that these nanocomposite films are potential candidate for a variety of packaging applications.

Rubber nanocomposites have currently fascinated vast attention owing to their flexibility and modulus, superior chemical and thermal stabilities. These enhanced properties compose rubber nanocomposites striking in different applications such as space industry, agriculture, medical, and packaging. This chapter focuses on diverse aspects of rubber nanocomposites with their filler properties. Nanofillers are introduced into rubber in accumulation to conventional fillers to increase the presentation plus different efficient properties of the rubber matrix depending on the applications. In the recent year, Ionic liquids (ILs) have gained much interest in research and development because of various dominating physical properties and that may be useful solvent for processing rubber for packaging.

Proteins are natural heteropolymers and are most vital nutrients essential for human survival and life. Proteins generally exist in nature either in the form of fibrous proteins (water insoluble) or in the form of globular proteins (water soluble). Proteins are also available abundant in nature and are biodegradable. Proteins provide a broad spectrum of functional and structural properties because of the presence of polar and nonpolar amino acids and are therefore ideal raw materials for the production of bioplastics used for packaging materials. At present, a number of protein-based films are produced for the purpose of packaging of food. The protein based films possess some unique characteristics such as; excellent optical properties (gloss and transparency), are good fat barriers, at low and intermediate humidity possess an excellent oxygen and organic vapor barrier and have moderate mechanical properties. The contents of this chapter are as follows: introduction, proteins for packaging materials, processing methods, shaping agents, and properties.

Layered double hydroxides (LDH’s) are a group of inorganic solid possessing structural similarity to that of brucite Mg(OH)₂. They are extensively used in the field of catalysis, biomedical applications, nuclear waste storage/treatment, water treatment, composites etc. LDH offer high surface area and a huge boundary with the polymer, which direct the material properties. For this reason, nowadays, LDHs are drawing much more attention as a filler material for the synthesis of polymer matrix composites. Presently, research on biopolymer based nanocomposite is on the increase because of their relative profusion, low cost and environmental friendly nature. Present chapter focuses on different synthesis route followed for development of LDH based bionanocomposites along with their characterisation. Further, various properties of the synthesised composite are assessed to find out the suitability of the material for different purposes.