ABSTRACT
Air pollution is one of the major global problems causing around 7 million dead per year. In fact, a connection between infectious disease transmission, including COVID-19, and air pollution has been proved: COVID-19 consequences on human health are found to be more severe in areas characterized by high levels of particulate matter (PM). Therefore, after the COVID-19 pandemic, the production of air filtration devices with high filtration efficiency has gained more and more attention. Herein, a review of the post-COVID-19 pandemic progress in nanofibrous polymeric membranes for air filtration is provided. First, a brief discussion on the different types of filtration mechanism and the key parameters of air filtration is proposed. The materials recently used for the production of nanofibrous filter membranes are presented, distinguishing between non-biodegradable polymeric materials and biodegradable ones. Subsequently, production technique proposed for the fabrication of nanofibrous membranes, i.e., electrospinning and solution blow spinning, are presented aiming to analyze and compare filtration efficiency, pressure drop, reusability and durability of the different polymeric system processed with different techniques. Finally, present challenges and future perspectives of nanofibrous polymeric membranes for air filtration are discussed with a particular emphasis on strategies to produce greener and more performant devices. © 2023 The Authors. Macromolecular Materials and Engineering published by Wiley-VCH GmbH.
ABSTRACT
Poly(lactic acid) (PLA) is a biopolymer with properties potentially suitable for fabricating packaging, medical devices, and healthcare products in a more friendly environmental way because this polymer presents biodegradability, compostability, low carbon footprint, and recyclability. However, PLA does not present intrinsic antimicrobial properties. Antimicrobial materials are highly desirable for manufacturing smart packaging and personal protective equipment to secure food and health professionals against pathogenic microorganisms. In this work, we evaluated the antimicrobial performance of (Ag)-coated PLA against Escherichia coli, Bacillus subtilis, and Omicron severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). PLA was rapidly coated with metallic Ag by pulsed direct current magnetron sputtering (pDCMS) for 5, 10, and 20 s. Atomic force microscopy indicates that the Ag coating grows predominantly on the PLA surface via a bulk diffusion mechanism. According to bactericidal and quantitative reverse transcription polymerase chain reaction assays, Ag-coated PLA was capable of inhibiting bacterial biofilm formation and disrupting the genetic material of the Omicron SARS-CoV-2. X-ray high-resolution photoelectron and nuclear magnetic resonance results suggest no polymer chain scission in the PLA bulk due to plasma thermal stress effects during Ag sputtering. © 2023 Elsevier Ltd
ABSTRACT
The demand for antibacterial fabric surfaces is increasing day by day. With the covid-19 pandemic situation, there is attention to antibacterial and antiviral nonwoven fabrics which can be used towards the development of personal protective wear. To reduce the environmental pollution caused by disposable and non-biodegradable polymer-made personal protective wear can be replaced by biodegradable polymers like poly(lactic) acid (PLA), which is quite similar to polypropylene, but biodegradable. In this study, the non-thermal plasma treatment method is used to increase the surface reactivity of the PLA nonwoven polymer surface. On the activated nonwoven surface copper nanoparticles are in-situ synthesized by chemical treatments. After 30 minutes of plasma treatment, better copper nanoparticle distribution and higher yield were achieved. Fourier transformed infrared spectroscopy (FTIR) and Scanning Electron Microscopy (SEM) were used to characterize the treated PLA nonwoven fabric surfaces. © 2022 IEEE.
ABSTRACT
Advancements in polymer science and engineering have helped the scientific community to shift its attention towards the use of environmentally benign materials for reducing the environmental impact of conventional synthetic plastics. Biopolymers are environmentally benign, chemically versatile, sustainable, biocompatible, biodegradable, inherently functional, and ecofriendly materials that exhibit tremendous potential for a wide range of applications including food, electronics, agriculture, textile, biomedical, and cosmetics. This review also inspires the researchers toward more consumption of biopolymer-based composite materials as an alternative to synthetic composite materials. Herein, an overview of the latest knowledge of different natural- and synthetic-based biodegradable polymers and their fiber-reinforced composites is presented. The review discusses different degradation mechanisms of biopolymer-based composites as well as their sustainability aspects. This review also elucidates current challenges, future opportunities, and emerging applications of biopolymeric sustainable composites in numerous engineering fields. Finally, this review proposes biopolymeric sustainable materials as a propitious solution to the contemporary environmental crisis. © 2022 Elsevier Ltd.
ABSTRACT
China’s plastic pollution has gotten worse, especially during the COVID pandemic when the city’s lockdowns boosted the food takeout business. Although the government has made efforts in curbing the use of conventional single-use plastic packaging, the problem is still looming up in the critical time of building ecological civilization. The key to resolve the overwhelming usage of disposable plastic packaging lies in reduction, along with using green alternatives: biodegradable packaging and returnable containers. The study investigated consumers’ willingness to adopt new alternatives by applying the extended classical behavioral theory: the theory of planned behavior (TPB). The measurement scale, developed upon previous literature, gains validated reliability and validity after running confirmatory factory analysis (CFA) in SmartPLS. The study distributed 536 questionnaires online, targeting consumers from Beijing and Shanghai. 430 valid samples were collected and analyzed, with results showing that consumers’ perceived behavior control has strong and positive effect on their willingness to pay more to using biodegradable packaging and willingness to participate in the returnable container programs. The environmental attitude, social norms and past green behavior show less direct relationships with people’s adopting intentions. Their effects on the intentions are mediated by perceived behavior control disproportionately. © 2022, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.
ABSTRACT
The application of cellulose in the food packaging field has gained increasing attention in recent years, driven by the desire for sustainable products. Cellulose can replace petroleum-based plastics because it can be converted to biodegradable and nontoxic polymers from sustainable natural resources. These products have increasingly been used as coatings, self-standing films, and paperboards in food packaging, owing to their promising mechanical and barrier properties. However, their utilization is limited because of the high hydrophilicity of cellulose. With the presence of a large quantity of functionalities within pristine cellulose and its derivatives, these building blocks provide a unique platform for chemical modification via covalent functionalization to introduce stable and permanent functionalities to cellulose. A primary aim of chemical attachment is to reduce the probability of component leaching in wet and softened conditions and to improve the aqueous, oil, water vapor, and oxygen barriers, thereby extending its specific use in the food packaging field. However, chemical modification may affect the desirable mechanical, thermal stabilities and biodegradability exhibited by pristine cellulose. This review exhaustively reports the research progress on cellulose chemical modification techniques and prospective applications of chemically modified cellulose for use in food packaging, including active packaging.
ABSTRACT
The main challenge of the economy is counteracting the adverse effects of progressive industrialisation on the environment around the world. Economic development that accompanies this trend correlates to production increase in not only consumer articles but also special application articles that are difficult to remanufacture, such as medical supplies. For many researchers, discovering innovative materials for special applications that could become an essential element of circular economy production is important. Measures to reduce the production of industrial materials whose waste is difficult to recycle are more and more apparent to manufacturers, especially when faced with the new financial situation in European Union, as one of its priorities is to implement the principles of circular economy. The purpose of the article is to analyse the current state of research on special-application biomaterials within the context of the circular economy. Empirical analysis is conducted for Poland compared to the rest of the European Union (EU) within the time-frame of 2014-2020, which is the most recent financial timeframe of the EU. The submitted studies are based on secondary data obtained mainly from European databases, as well as primary data resulting from the research works at Lukasiewicz Research Network-Institute of Biopolymers and Chemical Fibres.
ABSTRACT
Background: Expanded polystyrene (EPS), an inexpensive and widely available polymer, has been extensively employed in foam packaging. However, EPS-based foams cause environmental problems because they are non-biodegradable and little recycled. Therefore, developing foams from renewable sources for application in biodegradable packaging for food and express food delivery is essential to tackle pollution issues of synthetic plastics. Scope and approach: Starch is a renewable, abundant, and low-cost source with thermoplastic properties. For this reason, starch has been used as raw material to develop foams for packaging. This review emphasizes different strategies for improving the mechanical properties, processibility, and antimicrobial activity of starch-based foams and for decreasing their sensitivity to humidity, aiming at employing them as competitive replacement for EPS in packaging. Key findings and conclusions: Starch source, foaming process conditions, plasticizer concentration, fiber type and concentration, and addition of other polymers to form blends can affect the properties and morphology of biodegradable foams, so these factors should be better studied and optimized. Agroindustrial residues have become an interesting alternative to reduce the cost of foams, aiming at a competitive replacement for EPS. Few works have been developed on bioactive starch-based foams. Searching for starch-based foams with antiviral properties against SARS-Cov-2 is also necessary. © 2021 Elsevier Ltd
ABSTRACT
Poly(lactic acid) (PLA) is a biobased polyester with ever-growing applications in the fields of packaging and medicine. Despite its popularity, it suffers from inherent brittleness, a very slow degradation rate and a high production cost. To tune the properties of PLA, block copolymers with poly(propylene adipate) (PPAd) prepolymer were prepared by polymerizing L-lactide and PPAd oligomers via reactive extrusion (REX) in a torque rheometer. The effect of reaction temperature and composition on the molecular weight, chemical structure, and physicochemical properties of the copolymers was studied. The introduction of PPAd successfully increased the elongation and the biodegradation rate of PLA. REX is an efficient and economical alternative method for the fast and continuous synthesis of PLA-based copolymers with tunable properties.
ABSTRACT
Vaccination is the most valuable and cost-effective health measure to prevent and control the spread of infectious diseases. A significant number of infectious diseases and chronic disorders are still not preventable by existing vaccination schemes; therefore, new-generation vaccines are needed. Novel technologies such as nanoparticulate systems and adjuvants can enable safe and effective vaccines for difficult target populations such as newborns, elderly, and the immune-compromised. More recently, polymer-based particles have found application as vaccine platforms and vaccine adjuvants due to their ability to prevent antigen degradation and clearance, coupled with enhanced uptake by professional antigen-presenting cells (APCs). Polymeric nanoparticles have been applied in vaccine delivery, showing significant adjuvant effects as they can easily be taken up by APCs. In other words, polymer-based systems offer a lot of advantages, including versatility and flexibility in the design process, the ability to incorporate a range of immunomodulators/antigens, mimicking infection in different ways, and acting as a depot, thereby persisting long enough to generate adaptive immune responses. The aim of this review is to summarize the properties, the characteristics, the added value, and the limitations of the polymer-based nanovaccines, as well as the process of their development by the pharmaceutical industry.