The rapid accumulation of plastic waste is driving international demand for renewable plastics with superior qualities (e.g., full biodegradability to CO2 without harmful byproducts), as part of an ...expanding circular bioeconomy. Higher plants, microalgae, and cyanobacteria can drive solar-driven processes for the production of feedstocks that can be used to produce a wide variety of biodegradable plastics, as well as bioplastic-based infrastructure that can act as a long-term carbon sink. The plastic types produced, their chemical synthesis, scaled-up biorefinery concepts (e.g., plant-based methane-to-bioplastic production and co-product streams), bioplastic properties, and uses are summarized, together with the current regulatory framework and the key barriers and opportunities.
Fossil fuel and plastic production are currently integrated.
About 80% of manufactured plastic accumulates as waste in landfills and natural environments, presenting an increasing hazard.
Biodegradable and bio-based plastics present a viable and attractive alternative.
Well-crafted legislated standards on plastic biodegradability and environmental and animal/human health impacts could fast-track and optimize industry transition.
The diversity of bio-based feedstocks opens up the opportunity to produce an expanding range of renewable plastics.
Biodegradable plastics should ideally fully degrade to CO2 and water without harmful byproducts.
Durable bioplastics can act as carbon sinks if well integrated into large-scale long-term infrastructure.
Biorefinery and GMO strategies can support viable business development and the emerging circular bioeconomy.
Bioplastics
In article number 2302067, Eleftheria Roumel and co‐workers present a fast, simple, and scalable process to transform raw microalgae into a self‐bonded, recyclable, ...andbackyard‐compostable bioplastic with attractive mechanical propertiessurpassing those of other biobased plastics such as thermoplastic starch.
Free-standing films have been obtained by drop-casting cellulose-glycerol mixtures (up to 50 wt% glycerol) dissolved in trifluoroacetic acid and trifluoroacetic anhydride (TFA:TFAA, 2:1, v:v). A ...comprehensive examination of the optical, structural, mechanical, thermal, hydrodynamic, barrier, migration, greaseproof, and biodegradation characteristics of the films was conducted. The resulting cellulose-glycerol blends exhibited an amorphous molecular structure and a reinforced H-bond network, as evidenced by X-ray diffraction analysis and infrared spectroscopy, respectively. The inclusion of glycerol exerted a plasticizing influence on the mechanical properties of the films, while keeping their transparency. Hydrodynamic and barrier properties were assessed through water uptake and water vapor/oxygen transmission rates, respectively, and obtained values were consistent with those of other cellulose-based materials. Furthermore, overall migration levels were below European regulation limits, as stated by using Tenax® as a dry food simulant. In addition, these bioplastics demonstrated good greaseproof performance, particularly at high glycerol content, and potential as packaging materials for bakery products. Biodegradability assessments were carried out by measuring the biological oxygen demand in seawater and high biodegradation rates induced by glycerol were observed.
•TFA:TFAA solves cellulose and glycerol, forming amorphous films after solvent evaporation.•Glycerol addition plasticizes the films, maintaining transparency.•Glycerol enhances grease resistance while keeping low migration levels.•High biodegradation in seawater indicates the environmental friendliness of blends.
Development of renewable and biodegradable plastics with good properties, such as the gas barrier, UV-shielding, solvent resistance, and antibacterial activity, remains a challenge. Herein, ...cellulose/ZnO based bioplastics were fabricated by dissolving cellulose carbamate in an aqueous solution of NaOH/Zn(OH)42−, followed by coagulation in aqueous Na2SO4 solution, and subsequent hot-pressing. The carbamate groups detached from cellulose, and ZnO which transformed from cosolvent to nanofiller was uniformly immobilized in the cellulose matrix during the dissolution/regeneration process. The appropriate addition of ZnO (below 10.67 wt%) not only improved the mechanical properties but also enhanced the water and oxygen barrier properties of the material. Additionally, our cellulose/ZnO based bioplastic demonstrated excellent UV-blocking capabilities, increased water contact angle, and enhanced antibacterial activity against S. aureus and E. coli, deriving from the incorporation of ZnO nanoparticles. Furthermore, the material exhibited resistance to organic solvents such as acetone, THF, and toluene. Indeed, the herein developed cellulose/ZnO based bioplastic presents a promising candidate to replace petrochemical plastics in various applications, such as plastic toys, anti-UV guardrails, window shades, and oil storage containers, offering a combination of favorable mechanical, gas barrier, UV-blocking, antibacterial, and solvent-resistant properties.
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•Bioplastics fabrication from hazardous high-salt microalgal residues was successfully achieved.•Spirulina sp. residues served as excellent raw bioplastic materials were ...investigated.•The inorganic salts acted as the filler and the cross linker were comprehensively discussed.•Effect of inorganic salts on enhancing the tensile strength and flexibility was fully explored.
Plastic products have become a major contaminant in environmental ecology due to their recalcitrant biodegradation, poor management and risky disposal. Therefore, much research attention has been paid to developing the biodegradable bio-based plastics. However, many of the substitute bioplastics derived from agricultural materials may present a potential threat to food security and eco-systems. Herein, we propose a sustainable, eco-friendly and simple procedure to convert the hazardous high-salt contained microalgal residues into bioplastic film. With 35 % poly (vinyl alcohol) (PVA) assistance, the composite bioplastic films achieved 22 MPa tensile strength under alkali condition and 77 % elongation at break under acidic condition. The average maximum contact angle of 94.4° confirmed a desirable water resistance potential. The synthesis mechanism demonstrated that the inorganic salts existed in microalgal residues could act as the filler in shape of sheets under alkali condition or as the cross linker under acidic condition, significantly enhancing the practical feasibility. This work demonstrates a promising biodegradable bioplastics formed from sustainable eco-friendly waste reutilization process, providing a new insight for fundamentally reducing the plastics pollution.
The ubiquitous presence of plastic litter and its tending fate as marine debris have given rise to a strong anti-waste global movement which implicitly endorses bioplastics as a promising substitute. ...With ‘corporate social responsibility’ growing ever more popular as a business promotional tool, companies and businesses are continually making claims about their products being “green”, “environmentally friendly”, “biodegradable”, or “100% compostable”. Imprudent use of these words creates a false sense of assurance at the consumer end about them being responsible towards the environment by choosing these products. The policies surrounding bioplastics regulation are neither stringent not enforceable at both national and international stage which indirectly allow these “safe words” to be used as an easy plug to validate the supposed corporate social responsibility. Similar to conventional plastics, unregulated and mismanaged bioplastics could potentially create another environmental mayhem. Therefore, it is a crucial time to harness the power of law to set applicable standards with a high threshold for the classification of “bioplastics”, which companies can aspire to, and customers can trust. In this review, we analyse the multifarious international bioplastics standards, critically assess the potential shortcomings and highlight how the intersection of law with science and technology is crucial towards the reform of bioplastics regulation.
Graphic Abstract
The European Union is working towards the 2050 net-zero emissions goal and tackling the ever-growing environmental and sustainability crisis by implementing the
. The shift towards a more sustainable ...society is intertwined with the production, use, and disposal of plastic in the European economy. Emissions generated by plastic production, plastic waste, littering and leakage in nature, insufficient recycling, are some of the issues addressed by the European Commission. Adoption of bioplastics-plastics that are biodegradable, bio-based, or both-is under assessment as one way to decouple society from the use of fossil resources, and to mitigate specific environmental risks related to plastic waste. In this work, we aim at reviewing the field of bioplastics, including standards and life cycle assessment studies, and discuss some of the challenges that can be currently identified with the adoption of these materials.
The marine bacterium Cobetia sp. IU180733JP01 (5-11-6-3) can accumulate poly(3- hydroxybutyrate) P(3HB) during cultivation on alginate or waste Laminaria sp. Here, we examined this strain’s ability ...to utilize various carbon sources for P(3HB) production. When cultured in mineral salt medium containing 1% (w/v) glucose, fructose, glycerol, or gluconic acid, the strain showed better growth and higher P(3HB) production than on alginate, with fructose enabling the highest P(3HB) yield (0.8 ± 0.06 g/L). We also predicted metabolic pathways for P(3HB) synthesis based on draft genome sequence analysis, in which carbon sources are assimilated through Entner–Doudoroff and Embden–Meyerhof pathways, and the resultant acetyl-CoA is converted into P(3HB). Our findings reveal the potential of the 5-11-6-3 strain for application in bioplastic production from not only marine biomass but also other biomass and industrial wastes.
The growing environmental concern over petrochemical‐based plastics continuously promotes the exploration of green and sustainable substitute materials. Compared with petrochemical products, ...cellulose has overwhelming superiority in terms of availability, cost, and biodegradability; however, cellulose's dense hydrogen‐bonding network and highly ordered crystalline structure make it hard to be thermoformed. A strategy to realize the partial disassociation of hydrogen bonds in cellulose and the reassembly of cellulose chains via constructing a dynamic covalent network, thereby endowing cellulose with thermal processability as indicated by the observation of a moderate glass transition temperature (Tg = 240 °C), is proposed. Moreover, the cellulosic bioplastic delivers a high tensile strength of 67 MPa, as well as excellent moisture and solvent resistance, good recyclability, and biodegradability in nature. With these advantageous features, the developed cellulosic bioplastic represents a promising alternative to traditional plastics.
A “dynamic covalent network” reconstruction strategy is proposed for the fabrication of sustainable cellulosic bioplastics. By introducing dynamic linkages between cellulose chains, this cellulosic bioplastic is imparted with good thermo‐processability, competitive mechanical properties, excellent water and solvent resistance, as well as chemical and biological degradability. This approach provides a new route for developing sustainable and degradable bioplastics from resource‐abundant biomass.
The COVID-19 crisis generated changes in consumer behavior related to food purchase and the management of food packaging. Due to the intensification of online purchases for home delivery, there has ...been an increase in the use of food packaging (mostly non-biodegradable or non-renewable). Moreover, the fear of contamination with SARS-CoV-2 through contact with materials and surfaces has led to an intensified disposal of food packaging, promoting a setback in waste management.
The purpose of this short commentary is to address the impacts of increased use and disposal of food packaging during the COVID-19 pandemic. Technological solutions have been presented as tools to minimize the environmental impacts of the increased volume of disposed food packaging (namely, the development of biodegradable food packaging) as well as to minimize the occurrence of cross-contamination (namely, the incorporation of active antiviral components).
The consumer behavior in the COVID-19 pandemic requires actions concerning adoption of bioplastics for single-use food packaging. Polylactide (PLA) stands out for high production viability, performance comparable to those of petroleum-based thermoplastics, and carbon neutral life cycle. Moreover, active components including organic compounds (resveratrol, luteolin, myricetin etc.) and metals (e.g., copper, zinc, silver) can mitigate cross-contamination. Therefore, there are opportunities to reduce food packaging-related environmental footprints while also decreasing the occurrence of surface-mediated cross-contamination.
•The pandemic spurred online shopping, especially for food.•Delivery services grew (12–36%), increasing domestic packaging waste.•COVID-19 stimulated the growth (15%) of non-biodegradable food packaging waste.•Polylactide can be promising as biodegradable food packaging.
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