Materials For Packaging Applications Research Articles

Natural Plant Fiber‐Based Materials for Packaging Applications – A Review of Recent Innovations and Developments

AbstractNatural plant fiber‐based packaging materials emerges as sustainable alternatives to conventional plastic and non‐biodegradable packaging. This paper presents an extensive review of the current technological status quo and commercial applications of natural plant fiber‐based packaging such as fiber‐based foams, molded pulp packaging, fiber‐based bottles, fiber‐based flexible packaging, fiber‐based blister packaging and stretchable paper. It focuses on the manufacturing processes and newest technology advancement of environmentally sustainable materials, meanwhile, the currently industry‐leading, cutting‐edge commercial products also are discussed. In conclusion, the paper advocates for the pivotal role natural plant fiber‐based packaging plays in transforming the packaging industry, addressing waste reduction, resource conservation, and climate change. It encourages the wider adoption of these materials while acknowledging the complexities involved and the need for continuous research and development to ensure their viability and effectiveness in meeting stringent packaging requirements.

Enhancing PVA mulching films: Leveraging modified lignin as a bio-based crosslinking agent for improved mechanical strength, UV barrier, and biodegradability

In contemporary agriculture, eco-friendly mulching films present a promising alternative to conventional plastic mulching films. However, their potential is constrained by challenges related to limited biodegradation and barrier performance. Addressing these limitations, innovative lignin-carboxylated materials were employed as bio-based crosslinking agents to enhance diverse properties in the fabrication of PVA films. Alkali lignin was modified with diethylenetriaminepentaacetic acid (DTPA) to enhance its chemical reactivity. The abundance of carbonyl groups in modified lignin (Lig-DTPA) plays a significant role in establishing strong compatibility with PVA through covalent bonds. This interaction yielded remarkable enhancements, elevating both tensile strength and tensile modulus by an impressive 50.9 % and 60.1 %, respectively. The introduction of Lig-DTPA at 3 % into the PVA composite films resulted in excellent UV-blocking properties. Moreover, at 3 % ratios, the presence of lignin became visibly dispersed as clear spots across the film, indicating a relatively uniform state within the matrix. The study revealed a direct correlation: as the lignin content increased, the film exhibited heightened water solubility and enhanced biodegradability. The PVA/Lig-DTPA film displays promising potential for utilization as a mulching film material, offering anti-ultraviolet functionality and a high degradation rate. Furthermore, its versatility extends to potential applications in packaging materials, including seedling bowls, transplanting pots, and coating films for transportation purposes.

Construction and conversion of 2D and 3D patterns on the surface of transparent polyethylene terephthalate induced by near-infrared laser

The patterning of transparent PET film plays an indispensable role in the application of packaging materials. However, traditional processes such as ink printing limit the pattern to a 2D plane. Recently, laser irradiation technology has been demonstrated as a potential strategy for achieving surface patterning of polymer materials. Here, we found that metallic oxide substrate can absorb laser energy and transfer it to transparent PET film through the interface, thereby improving the absorption of laser by PET. The preparation process of metallic oxide substrate is low-cost, scalable, and easy to prepare. Irradiation experiments were conducted at different energy densities, and the results show that the laser-induced patterns on the surface of PET film can be arbitrarily transformed between 2D and 3D. The PET film absorbs a large amount of heat through the interface with the substrate, which is the main factor regulating the pattern morphology. In addition, the controllability of photothermal conversion between interfaces enables laser-induced patterns to be designed locally and arbitrarily, thus achieving practical applications. The present method may open a new avenue for the application of laser patterning and meet the extensive requirements of transparent polymer materials in the fields related to surface 2D/3D pattern design.

Strong, bacteriostatic and transparent polylactic acid-based composites by incorporating quaternary ammonium cellulose nanocrystals

Renewable natural fibers (e.g., cellulose nanocrystals (CNCs)) are being applied for reinforcing bio-based polylactic acid (PLA). For improvement in the interfacial compatibility between CNCs and PLA and the dispersibility of CNCs, a quaternary ammonium salt-coated CNCs (Q-CNCs) hybrid was prepared in this study based on an esterification self-polymerization method, and such hybrid was further utilized as a new strengthening/toughening nanofiller for producing the Q-CNCs-reinforced PLA composite. The results confirmed that quaternary ammonium salt coatings could efficiently enhance CNCs/PLA interfacial compatibility via mechanical interlocking and semi-interpenetrating networks. Attributing to the synergistic effect of quaternary ammonium salts and CNCs, a considerable enhancement in processing, mechanical, and thermal properties was gained in the obtained Q-CNCs-reinforced PLA composite. With the addition of 0.5 wt% Q-CNCs, the tensile strength, Young's modulus, and elongation at break of the Q-CNCs-reinforced PLA composite was raised by approximately 23 %, 37 % and 18 %, respectively; compared with pure PLA, the obtained composite had excellent bacteriostatic properties and good transparency. This work discusses the development of high-performance, low-cost and sustainable PLA-based composites on a potential application in packaging materials.

Implementation of a Low-Cost Chipless RFID System With Paper-Based Substrates Printed Tags for Traceability Applications in the Packaging Sector

Increasing competitiveness as well as levels of sustainability are some of the main challenges that the packaging sector is facing. The introduction of information and communication technologies provides new functionalities, such as traceability within logistic processes. In this context, RFID technologies can play a key role but can also pose hurdles, owing to increased cost, as well as to difficulties in relation with recycling and complying with product circularity. In this sense chipless RFID opens new possibilities, by avoiding the use of information coded chips, reducing costs in material and placement, as well by improving recyclability. In this work, a frequency based chipless RFID solution is presented, in which 2D geometrical patterns printed with conductive ink, resembling transmitive or reflective metasurfaces, are designed and integrated within paper-based substrates. An in-house reader system is implemented based on conventional Software Defined Radio platforms in the 0-6GHz and in the 0-12GHz range, in which received signal post-processing is performed to increase reader sensitivity, without the need of using Vector Network Analyzer equipment. Moreover, in order to reduce material waste, an automatic fault detection system based on artificial vision coupled to a robot arm is designed and tested. Different prototypes in paper substrates as well as in reference printed circuit boards have been fabricated and measured, showing good agreement. The proposed solution provides a feasible chipless RFID system with a portable low-cost reader which can be embedded in paper/cardboard materials in packaging applications.

Life cycle and environmental cost assessment of ultrasound-assisted alkaline extraction of hemicellulose by sugarcane bagasse pith

Hemicellulose can provide excellent oxygen resistance for packaging film, which is considered to be able to solve the environmental burdens and natural resource consumption problems of traditional petroleum-based packaging. The extraction of hemicellulose from numerous agricultural and forestry wastes, together with its application in packaging materials, has attracted worldwide attention. In this study, the life cycle assessment method was used to qualify the potential environmental impact of ultrasound-assisted alkaline extraction of hemicellulose, including alkali-soluble hemicellulose (AHC) and water-soluble hemicellulose (WHC). The results show that the washing and drying process of AHC extraction and the rotary evaporating together with sedimentation process of WHC extraction are the main contribution of environmental burdens. There are significant differences in ODP, COD, POFP, and NH3–N between AHC and WHC extraction, which are mainly caused by ethanol consumption during the washing and drying process of AHC extraction, while the sedimentation process of WHC extraction moderates the difference trend. From the results of normalization, the environmental implication of WHC is significantly lower than that of AHC. In the utopia scenario, the synergistic effect of ethanol recovery and clean energy substitution can reduce the environmental burdens by 77.4%, and reduce environmental costs by 89%. WHC can be preferred as the raw material of packaging film, but the premise is that the functions of the two kinds of hemicelluloses are consistent. The environmental footprint and cost of hemicellulose extraction process can be further reduced by recycling ethanol and using clean energy, especially in terms of GWP and AP indicators. In this study, quantitative evaluation of environmental profile and environmental cost can provide data support and a fresh perspective on the sustainable development of hemicellulose and biomass refining technology.

Turning Recycled Cardboard Container-Derived Lignin-Containing Cellulose Nanofibrils into a Robust Gas Barrier UV-Shielding Film

Self-standing cellulose nanofibril (CNF) films are regarded as one of the promising alternatives to current petroleum-based packaging materials mostly due to their ability to form dense self-assembled structures exhibiting high gas barrier properties. Nonetheless, one of the major obstacles to the commercialization of these materials in packaging applications is the high cost of raw materials and production energy. In this study, we created self-standing films of lignin-containing cellulose nanofibrils (LCNFs) derived from a recycled old corrugated cardboard (OCC) pulp that costs less than bleached softwood Kraft (BSK) pulp and requires half as much energy for refining to obtain the same quality of material. The low zeta potential (−3.83 mV) of OCC-derived LCNFs (OCC-LCNFs) resulted in aggregation of the fibrils in aqueous suspension, leading to considerable unpredictability in oxygen permeability (OP) values (coefficient of variation 36%). The addition of 3 wt % (based on the dry weight of LCNFs) carboxymethyl cellulose lowered the coefficient of variation to 16% with an average OP of 1478 (cc.μm/m2.atm.day) at 80% relative humidity. Because the OP was higher than that of the CNF film made from BSK-derived CNF (BSK-CNFs), we demonstrated that ionic crosslinking with trivalent aluminum ion or covalent crosslinking with polyamide epichlorohydrin decreased the OP by 30% at 23 °C and 80% relative humidity while also significantly enhancing the tensile strength and modulus. In addition, the presence of lignin in OCC resulted in a relatively lower water vapor permeability value in OCC-LCNF films compared to BSK-CNF films. Moreover, OCC-LCNF films showed complete UV-shielding (200–400 nm) property. Overall, this work provides a new opportunity to exploit a recycled and inexpensive source of CNFs to produce robust gas barrier materials for packaging applications.

Facile fabrication of hydrophobic paper by HDTMS modified chitin nanocrystals coating for food packaging

Paper is an inherent hydrophilic material due to the hydroxyl groups contained in cellulose, which limits its applications in packaging materials. This study proposed a simple one-step method for preparing hydrophobic paper by introduction of chitin nanocrystals (ChNCs) and hexadecyltrimethoxysilane (HDTMS). The surface chemistry and morphology of coated paper were studied in detail. The 2%ChNCs/HDTMS coated paper was highly hydrophobic with a water contact angle greater than 130°, mainly due to the low surface energy provided by HDTMS. Compared with uncoated paper, the hydrophobic paper's tensile strength and water vapor barrier are significantly improved due to the addition of ChNCs. Meanwhile, the hydrophobic paper shows excellent environmental tolerance and mechanical stability. The survival rate of L929 cells on the modified paper was more than 80% by CCK-8 assay, which proved that the nanocoating was safe. In addition, the obtained hydrophobic coated paper can hold water, cola, green tea, milk, coffee, and orange juice for a long time and can be used as a straw to absorb liquid. This work prepared high-performance and green hydrophobic paper, which exhibits wide applications in food packaging. • Hydrophobic paper coated with ChNCs/HDTMS was fabricated by one-step method. • ChNCs/HDTMS enhanced water vapor barrier and mechanical properties of paper. • The coated paper exhibited excellent environmental tolerance. • Hydrophobic paper showed antibacterial adhesion and satisfied biocompatibility. • The hydrophobic paper can be made into straw and paper cup.

In situ nanofibrillar fully-biobased poly (lactic acid)/poly (ethylene 2,5-furandicarboxylate) composites with promoted crystallization kinetics, mechanical properties, and heat resistance

To save resources and improve energy efficiency, an efficient, economical, and environmentally friendly technology is needed to produce high-performance poly (lactic acid) (PLA). However, the poor heat resistance of PLA greatly restricts its application in packaging materials and other fields. Herein, a scalable and efficient method was developed to fabricate high-performance PLA by combining bio-based nanofibrillar reinforcing material. In-situ nanofibrillar PLA/ poly (ethylene 2,5-furandicarboxylate) (PEF) composites were successfully obtained using a fast and straightforward melt extrusion and spinning process. PEF nanofibers with a high aspect ratio were well dispersed in PLA matrix with an average diameter of 80 nm, which dramatically enhanced the rheological properties, crystallization kinetics, and dynamic mechanical properties of PLA. Unprecedently, such fully bio-renewable PLA/PEF nanofibers composites exhibited excellent heat resistance. With the addition of 3 wt% PEF, the heat resistance of PLA was significantly increased from approximately 59.6 to 157 ℃. This environmentally-friendly in-situ nanofibrillar PLA/PEF composites with high heat resistance will potentially broaden the application of PLA in areas like packaging materials and automotive interiors.

Green and Efficient Preparation of Tailed Lignin Nanoparticles and UV Shielding Composite Films.

Lignin nanoparticles (LNP) with various morphologies could be prepared with solvent–antisolvent methods. However, the employed toxic chemicals limited its large-scale application. In this study, an extremely green method using only ethanol and water as solvent and antisolvent was reported. Besides, with the syringaldehyde (SA) addition and its anchoring action on the lignin particles, a forming process of the tailed structure was observed and resulted. Moreover, the improved electronegativity originating from the phenolic hydroxyl groups enhanced the size distribution uniformity, and the new absorption peaks at 1190 cm−1 demonstrated the involvement of SA in the LNP formation. Lastly, the tailed lignin nanoparticles (T-LNP) composited with, respectively, polyvinyl alcohol, chitosan, cellulose nanofibers, cationic etherified starch, and sodium alginate were successfully prepared. The outstanding UV-shielding and free radical scavenging properties in the above composites showed their great potential in wide applications in packaging materials.

Preparation and benchmarking of novel cellulose nanopaper.

Synthetic polymers and plastics which are currently used as barrier materials in packaging applications are neither renewable nor biodegradable. Nanopaper, which is obtained by breaking down cellulose fibers into nanoscale particles, have unique properties with the potential to replace synthetic packaging materials, but requires very high energy to mechanically process the fibers into nanopaper. This research investigates whether refining alone can be used to produce nanopaper with sufficient quality for packaging applications. Nanopaper was produced from Bleached Eucalyptus Kraft (BEK) refined with a PFI mill and from Northern Bleached Softwood Kraft (NBSK) refined in a pilot disc refiner. Both trials found a plateau for oxygen permeability and water vapour permeability that was reached after 1800 kWh/t and 12,000 kWh/t for refining in the pilot disc refiner and PFI mill, respectively. Refining beyond these optima produced either little or no reduction in permeability, while increasing the drainage time to form a sheet. However, elastic modulus, strain at break and sheet light transmittance did continue to increase. The plateau oxygen permeability of ~ 1.24 (cc µm)/(m2 day kPa) is 1–3 orders of magnitude lower than the oxygen permeability for PET and LDPE, respectively, while the plateau water vapour permeability ~ 3 × 10–11 g/m.s. Pa was 1–2 orders of magnitude higher than for PET and LDPE. The improved strength and barrier properties of nanopaper achieved at lab and pilot scale mechanical refining process promises a sustainable alternative to conventional packaging.Graphical abstract Supplementary InformationThe online version contains supplementary material available at 10.1007/s10570-022-04563-0.

Poly(lactic acid)/Poly(3-hydroxybutyrate) Biocomposites with Differently Treated Cellulose Fibers.

The growing concern about environmental pollution has generated an increased demand for biobased and biodegradable materials intended particularly for the packaging sector. Thus, this study focuses on the effect of two different cellulosic reinforcements and plasticized poly(3-hydroxybutyrate) (PHB) on the properties of poly(lactic acid) (PLA). The cellulose fibers containing lignin (CFw) were isolated from wood waste by mechanical treatment, while the ones without lignin (CF) were obtained from pure cellulose by acid hydrolysis. The biocomposites were prepared by means of a melt compounding-masterbatch technique for the better dispersion of additives. The effect of the presence or absence of lignin and of the size of the cellulosic fibers on the properties of PLA and PLA/PHB was emphasized by using in situ X-ray diffraction, polarized optical microscopy, atomic force microscopy, and mechanical and thermal analyses. An improvement of the mechanical properties of PLA and PLA/PHB was achieved in the presence of CF fibers due to their smaller size, while CFw fibers promoted an increased thermal stability of PLA/PHB, owing to the presence of lignin. The overall thermal and mechanical results show the great potential of using cheap cellulose fibers from wood waste to obtain PLA/PHB-based materials for packaging applications as an alternative to using fossil based materials. In addition, in situ X-ray diffraction analysis over a large temperature range has proven to be a useful technique to better understand changes in the crystal structure of complex biomaterials.

Study of Mechanical Properties of Recycled Polyethylene of High and Low Density

High and low density polyethylene materials constitute about 48% of total weight of plastics waste in Europe, that depends on the frequent use of these materials in packaging applications. This paper analyze the recycling effect on the mechanical properties of high and low density polyethylene (HDPE and LDPE). A mechanical recycling process was tested for the plastics waste of high and low density polyethylene, then a tensile and impact tests were performed on different mixing ratios for each of the both materials ranging from 100% of the virgin material and up to 100% of the recycled material with a difference of 10% of the sample to the other. This paper discusses the tensile properties of tensile stress at the fracture, elongation and modulus of elasticity and the impact test results for HDPE and LDPE were compared with each other.

Pretreatment of lignin-containing cellulose micro/nano-fibrils (LCMNF) from corncob residues

The explorations of valorizing crop wastes have drawn more and more attention in recent years. Among them, preparing lignin-containing cellulose micro/nano-fibrils (LCMNF) is an extremely promising strategy. In this study, LCMNF with a significant amount of lignin were prepared from corncob residues (CCR) left from xylose extraction. The focus of the work was to explore the influence of different pretreatment methods on the properties of LCMNF and the barrier properties of resulting films. The pretreatment methods included alkali-sulfite (AS), alkali-hydrogen peroxide (AP) and mediator-free laccase (ML), in which lignin was the pretreatment object. The results show that AS and AP increase the reactivity of lignin and cause the partial dissolution of lignin. In addition, the residual lignin does not affect the fibrillation of the CCR, but it reduces the water retention value of the resulting LCMNF, compared with lignin-free cellulose micro/nano-fibrils (DCMNF) from fully delignified CCR. As a result, the water contact angles of films from LCMNF are increased. Although different pretreatments have different effects on the barrier properties of films from LCMNF, the three preprocessing methods decrease the water vapor permeability (WVP) and oxygen permeability (OP). Especially for AS pretreatment, the film gives the lowest WVP (1.72 g mm/(m2 day kPa), at 23 °C and 50%RH) and OP (0.85 (cm μm)/(m2·24 h kpa), at 23 °C and 0% RH), which makes it promising for further application in packaging materials.

Thermoforming of planar polymer optical waveguides for integrated optics in smart packaging materials

Abstract The innovations in smart packaging will open up a wide range of opportunities in the future. This work describes the processing of additive manufactured and planar integrated polymer optical waveguides for use in smart packaging products. The previously published combination of flexographic and Aerosol Jet printing is complemented by thermoforming and thus creates three-dimensional integrated multimode waveguides with optical attenuation of 1.9 dB/cm ± 0.1 dB/cm @ 638 nm. These properties will be the basis to develop smart applications in packaging materials.

Enhancement of water resistance and antimicrobial properties of paper sheets by coating with shellac

The present study was focused on the effect of shellac as a natural polymer on the mechanical, physical, and antimicrobial properties of the paper sheets. The surface modification of paper sheets was carried out using different shellac solutions. The capability of the treated sheet to absorb water and to permit air follow was studied by Cobb test and air permeability, respectively. It was found that the treated sheet had little affinity for water and low air permeability. The change of sheet surface properties after modification was ascertained by scanning electron microscopy and Fourier Transform Infrared Spectrophotometer (FT-IR). The shellac treated paper sheet displayed improved mechanical properties when compared with untreated paper sheet. The shellac treated sheets exhibit efficient antimicrobial activity against Staphylococcus aureus, Pseudomonas aeruginosa, and Candida albicans. Consequently, the prepared paper sheet can be used as novel materials for packaging applications.

Improving the barrier character of poly(caprolactone): Transport properties and free volume of immiscible blends

ABSTRACTIn this work, the barrier character of poly(caprolactone) is improved with the addition of a poly(hydroxy amino ether). The analysis by means of thermal, thermomechanical, and morphology characterization reveals that the blends are partially miscible. The characterization of the morphology has revealed that the blends show a droplet matrix morphology. The free volume of the samples has been characterized by positron annihilation lifetime spectroscopy observing a decrease in the free volume as the poly(hydroxyamino ether) (PHAE) content increases. The barrier character to water vapor and carbon dioxide is greatly improved with the addition of PHAE. However, the observed improvement does not arise only from the reduced free volume, playing the interactions between penetrants and polymers a major role. Overall, this work aims to provide a further insight on the factors affecting the improvement of the barrier character of biodegradable polymers, which would allow developing new materials for packaging applications. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 48018.

Comparative study of cellulose and lignocellulose nanopapers prepared from hard wood pulps: Morphological, structural and barrier properties

The current research intended to explore the hardwood pulps capabilities to produce cellulose (CNPs) and lignocellulose nanopapers (LNPs) and feasible enhancement of their performance for possible utilization in sustainable packaging. The high-yield hardwood pulps were then bleached to show the fundamental role of residual lignin on the ultrafine fibrillation processes, structural and barrier properties of nanopapers. X-ray diffraction results demonstrated that the crystallinity and crystallite size of CNPs and LNPs were lower than the corresponding starting pulps. Field emission scanning electron microscopy analysis showed that the average nanofibril diameter of the CNPs and LNPs are 35 nm and 23 nm, respectively. Elastic modulus of LNPs was found to be 9.1 and 10.8 GPa for Chemimechanical and Neutral sulfite semichemical pulps, respectively. The semi-porous and consolidated structure of LNPs prepared from CMP fibers contributed to yield the lowest water vapor transmission rate i.e. 108 g/m2.day which is promising for potential applications in packaging materials.

Cu-Ba0.7Sr0.3TiO3 composites for electronic packaging

With the rapid growth of Electronic industries, there is an increasing demand for high-performance electronic packaging materials. In a harsher service environment, the high-temperature performance and thermal cycling stability are required to run the electronic system. In order to remove the heat generated in electronic systems, appropriate materials must be developed as heat sinks. In this work, we report Ba0.7Sr0.3TiO3 nanoparticles, which were synthesized using a citrate gel method, used as reinforcements in a Cu matrix composite. These composites have shown the coefficient of thermal expansion value compatible to that of Si and GaAs at the same time having a superior thermal conductivity of 292.213 W/m K compared to SiC reinforced composites, making it a promising material for packaging applications in semiconductor industries.

Increasing the quality and impact of manuscripts in the field of new materials

Increasing the quality and impact of manuscripts in the field of new materials