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27,482 result(s) for "Plastics - chemistry"
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Development and characterization of starch bioplastics as a sustainable alternative for packaging
Due to the growing environmental concerns of petroleum-based plastics, there has been a surge of interest in biodegradable alternatives. In this study, starch-based bioplastic was prepared using biopolymers extracted from corn and potato and the biopolymer was mixed with calcium carbonate (filler) and plasticizers (glycerol-sorbitol) and evaluated. For the fabricated formulation, Taguchi analysis gave an optimal formulation of 9 g corn starch, 9 mL glycerol, and 2.5 g calcium carbonate, having a well-balanced mechanical strength, flexibility, and biodegradability. The results showed a major improvement in tensile strength of 22.5% (6.08 MPa) and a 31.7% increase in Young’s modulus (0.103 GPa), compared to the least effective sample. In biodegradation tests, the degradation rate of C1 (66.68%) was the fastest, while C3 had a slower rate (29.08%). Moisture absorption varied considerably, with sample COM3 absorbing 25.92% compared to just 4.35% for P3, while P3 absorbed only 4.35%. Among compounds, the higher and lower percentage for water solubility were for P1 (20.50%) and C3 (49.04%) respectively. These results underscore the potential of starch-based bioplastics for sustainable packaging, offering an environmentally friendly option compared to traditional plastics.
Biomimetic layered, ecological, advanced, multi-functional film for sustainable packaging
Plastic pollution is one of most daunting sustainability challenges. Multi-functional and biodegradable plastics are critical for both desirable end-of-life outcomes and petrochemical plastics replacement. Current bioplastics are either: short of mechanical properties, like polyhydroxybutyrate (PHB); lack room temperature biodegradability, like polylactic acid (PLA); or lack the functionality to create additional values. Here, we present the bioinspired Layered, Ecological, Advanced, and multi-Functional Film (LEAFF), for sustainable plastic packaging. This biomimetic composite, based on the structure of the natural plant leaf, synergistically improves mechanical strength while empowering PLA for rapid ambient soil biodegradability, achieving complete degradation in 5 weeks. The film is also highly transparent and water stable, and achieves high gas barrier properties to improve food shelf life and reduce waste. The biomimetic design showcases the synergistic advantage leveraged by the LEAFF’s multilayer structure to enhance mechanical performance while simultaneously retaining biodegradability and achieving multifunctionality for broad applications. Designing biodegradable plastics is highly desirable, though it has been a challenge to balance mechanical properties with biodegradability. Here the authors design a multilayered biodegradable composite without compromising the mechanical properties.
Disintegration of commercial biodegradable plastic products under simulated industrial composting conditions
Biodegradable plastics are often promoted as sustainable alternatives to conventional plastics. Nevertheless, significant knowledge gaps exist regarding their degradation under relevant conditions, particularly when compounded into commercial products. To this end, the present research investigates the disintegration of ten commercially available biodegradable plastic products under simulated industrial composting conditions. The tested products included polymer compositions of either polylactic acid (PLA), polybutylene adipate terephthalate (PBAT)/starch, or polyhydroxyalkanoate (PHA), covering both flexible and rigid plastics. These products comprised three waste bags, one waste bag drawstring, one food bag (flexible plastics), two flower pots, one food container, one plate, and one lid (rigid plastics). Among the tested products, nine were marketed as compostable. Of these, six were certified under the European standard EN 13432 for compostable packaging, two held TÜV Austria’s “OK compost home” certification, and one was labeled as compostable but lacked certification. Additionally, one product was labeled as 100% biodegradable but lacked certification, and the environment in which the product could biodegrade was not specified. Disintegration was determined according to ISO 20200 in laboratory scale tests conducted at 58 °C with 55% moisture content over 90 days. Results showed disintegration degrees ranging from 75 to 100%, with five products achieving complete disintegration. Two products, however, reached only 75% disintegration. Following the disintegration test, compost particles smaller than 2 mm were examined for microplastics (MPs) via light microscopy. MPs were detected in compost undersieves for two of the ten biodegradable plastic products, while no MPs were detected for the conventional plastics. Notably, the visual inspection was performed without pretreating the compost matrix due to the observed degradation of biodegradable plastics when using chemicals for oxidative digestion. Considering the limitations of visual MP observation without pretreatment, future research should prioritize the development of methods for extracting biodegradable MPs from complex matrices like compost. Enhanced extraction methods are essential for understanding compost’s potential role as a source of MPs in the environment.
Bioplastic Production Using Natural Extracts with Cellulose Assisted by Experimental and Computational Screening
The increasing demand for sustainable and environmentally friendly materials has prompted intensive research into developing bioplastics as viable alternatives to conventional petroleum-derived plastics. Here, we report a novel approach to bioplastic production by employing plant extract-based solvents to partially dissolve cellulose, a fundamental biopolymer precursor. Using plant-derived solvents addresses concerns surrounding the environmental impact of traditional solvent-based processes, as per the principles of green chemistry. Using computational screening, some natural products were identified from the integrated database resource MEGx. Six natural sources were selected based on their molecular weight, high pKa, and chemical classification. Thin-layer chromatography (TLC) and column chromatography confirmed the presence of molecules in the extracts. Bioplastics were prepared with 1, 3, 6, 10, and 15 wt.% plant extract concentrations. Control samples without conventional dissolved and positive controls were also studied to compare their properties with novel bioplastics. Chemical characterization and biodegradability tests were performed. Degradation in water and soil tests for 35 days showed that the biodegradability of the bioplastics with natural extracts at higher concentrations was faster than that of the control samples. By day 35, bioplastics containing 15 wt.% of the D1 W extract showed rapid degradation, with higher weight loss compared with the conventional controls. The positive control (C4), containing NaOH and glycerol, degraded more slowly than the plant extract-based formulations. Also, the test indicated that the natural dissolvent’s influence on the water uptake of the material produced a better performance than the control samples. The surfaces of the bioplastic formulations were analyzed using a scanning electron microscope (SEM) at different magnifications. The findings presented here hold promise for advancing the field of bioplastics and contributing to the sustainable utilization of plant resources for eco-friendly material production.
Selective recovery of pyrolyzates of biodegradable (PLA, PHBH) and common plastics (HDPE, PP, PS) during co-pyrolysis under slow heating
Pyrolytic synergistic interactions, in which the production of pyrolyzates is enhanced or inhibited, commonly occur during the co-pyrolysis of different polymeric materials, such as plastics and biomass. Although these interactions can increase the yield of desired pyrolysis products under controlled degradation conditions, the desired compounds must be separated from complex pyrolyzates and further purified. To balance these dual effects, this study was aimed at examining pyrolytic synergistic interactions during slow heating co-pyrolysis of biodegradable plastics including polylactic acid (PLA) and poly(3-hydroxybutyrate- co -3-hydroxyhexaoate) (PHBH) and petroleum-based plastics including high-density polyethylene (HDPE), polypropylene (PP), and polystyrene (PS). Comprehensive investigations based on thermogravimetric analysis, pyrolysis–gas chromatography/mass spectrometry, and evolved gas analysis-mass spectrometry revealed that PLA and PHBH decompose at lower temperatures (273–378 °C) than HDPE, PP, and PS (386–499 °C), with each polymer undergoing independent decomposition without any pyrolytic interactions. Thus, the independent pyrolysis of biodegradable plastics, such as PLA and PHBH, with common plastics, such as HDPE, PP, and PS, can theoretically be realized through temperature control, enabling the selective recovery of their pyrolyzates in different temperature ranges. Thus, pyrolytic approaches can facilitate the treatment of mixed biodegradable and common plastics.
Sustainable DNA-polysaccharide hydrogels as recyclable bioplastics
Traditional petrochemical-derived plastics are challenging to recycle and degrade, and the existing (re)process methods are organic solvent-based and/or energy-intensive, resulting in significant environmental contamination and greenhouse gas emissions. This study presents a sustainable bioplastic material characterized by multi-closed-loop recyclability and water (re)processability. The bioplastics are derived from abundant polysaccharide sources of dextran, alginic acid, carboxymethyl cellulose, and DNA of plant and living organism waste. The process involves chemical oxidation of polysaccharides to produce aldehyde-functionalized derivatives, which subsequently form reversible imine covalent bonds with amine groups in DNA. This reaction yields water-processable polysaccharide/DNA crosslinked hydrogels, serving as raw materials for producing sustainable bioplastics. The bioplastic products exhibit (bio)degradability and recyclability, enabling aqueous recovery of the hydrogel constituents through plastic hydrolysis and the natural biodegradability of DNA and polysaccharides. These products demonstrate excellent resistance to organic solvents, self-healing, scalability, and effective processing down to nanometer scales, underscoring their potential for broad and versatile applications. The work provides potential pathways for advancing sustainable and environmentally friendly bioplastic materials. Bioplastics are desirable materials for the replacement of petrochemical-derived plastics, but achieving the desired properties can be challenging. Here, the authors report a bioplastic formed from a combination of polysaccharide sources and DNA from living organism waste, with biodegradability and recyclability.
Microbial Genes for a Circular and Sustainable Bio-PET Economy
Plastics have become an important environmental concern due to their durability and resistance to degradation. Out of all plastic materials, polyesters such as polyethylene terephthalate (PET) are amenable to biological degradation due to the action of microbial polyester hydrolases. The hydrolysis products obtained from PET can thereby be used for the synthesis of novel PET as well as become a potential carbon source for microorganisms. In addition, microorganisms and biomass can be used for the synthesis of the constituent monomers of PET from renewable sources. The combination of both biodegradation and biosynthesis would enable a completely circular bio-PET economy beyond the conventional recycling processes. Circular strategies like this could contribute to significantly decreasing the environmental impact of our dependence on this polymer. Here we review the efforts made towards turning PET into a viable feedstock for microbial transformations. We highlight current bottlenecks in degradation of the polymer and metabolism of the monomers, and we showcase fully biological or semisynthetic processes leading to the synthesis of PET from sustainable substrates.
The role of biotechnology in the transition from plastics to bioplastics: an opportunity to reconnect global growth with sustainability
Building new value chains, through the valorization of biomass components for the development of innovative bio‐based products (BBPs) aimed at specific market sectors, will accelerate the transition from traditional production technologies to the concept of biorefineries. Recent studies aimed at mapping the most relevant innovations undergoing in the field of BBPs (Fabbri et al. 2019, Final Report of the Task 3 BIOSPRI Tender Study on Support to R&I Policy in the Area of Bio‐based Products and Services, delivered to the European Commission (DG RTD)), clearly showed the dominant position played by the plastics sector, in which new materials and innovative technical solutions based on renewable resources, concretely contribute to the achievement of relevant global sustainability goals. New sustainable solutions for the plastic sector, either bio‐based or bio‐based and biodegradable, have been intensely investigated in recent years. The global bioplastics and biopolymers market size is expected to grow from USD 10.5 billion in 2020 to USD 27.9 billion by 2025 (Markets and Markets, 2020, Bioplastics & Biopolymers Market by Type (Non‐Biodegradable/Bio‐Based, Biodegradable), End‐Use Industry (Packaging, Consumer Goods, Automotive & Transportation, Textiles, Agriculture & Horticulture), Region ‐ Global Forecast to 2025), and this high growth is driven primarily by the growth of the global packaging end‐use industry. Such relevant opportunities are the outcomes of intensive scientific and technological research devoted to the development of new materials with selected technical features, which can represent feasible substitutes for the fossil‐based plastic materials currently used in the packaging sectors and other main fields. This article offers a map of the latest developments connected to the plastic sector, achieved through the application of biotechnological routes for the preparation of completely new polymeric structures, or drop‐in substitutes derived from renewable resources, and it describes the specific role played by biotechnology in promoting and making this transition faster. Biotechnology holds the power to boost the transition from fossil‐based to bio‐based plastics by offering new sustainable routes for polymer synthesis based on waste biomasses.
Gelatine Blends Modified with Polysaccharides: A Potential Alternative to Non-Degradable Plastics
Non-degradable plastics of petrochemical origin are a contemporary problem of society. Due to the large amount of plastic waste, there are problems with their disposal or storage, where the most common types of plastic waste are disposable tableware, bags, packaging, bottles, and containers, and not all of them can be recycled. Due to growing ecological awareness, interest in the topics of biodegradable materials suitable for disposable items has begun to reduce the consumption of non-degradable plastics. An example of such materials are biodegradable biopolymers and their derivatives, which can be used to create the so-called bioplastics and biopolymer blends. In this article, gelatine blends modified with polysaccharides (e.g., agarose or carrageenan) were created and tested in order to obtain a stable biopolymer coating. Various techniques were used to characterize the resulting bioplastics, including Fourier-transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA)/differential scanning calorimetry (DSC), contact angle measurements, and surface energy characterization. The influence of thermal and microbiological degradation on the properties of the blends was also investigated. From the analysis, it can be observed that the addition of agarose increased the hardness of the mixture by 27% compared to the control sample without the addition of polysaccharides. In addition, there was an increase in the surface energy (24%), softening point (15%), and glass transition temperature (14%) compared to the control sample. The addition of starch to the gelatine matrix increased the softening point by 15% and the glass transition temperature by 6%. After aging, both compounds showed an increase in hardness of 26% and a decrease in tensile strength of 60%. This offers an opportunity as application materials in the form of biopolymer coatings, dietary supplements, skin care products, short-term and single-contact decorative elements, food, medical, floriculture, and decorative industries.
Efficiency of Polyethylene Terephthalate Glycol Thermoplastic Material to Functional and Expansion Forces in Orthodontic Applications: An Experimental Study
Background: While polyethylene terephthalate glycol (PETG) is widely used in orthodontic appliances such as clear aligners and retainers, there is limited experimental data assessing its performance under functional stresses, such as those encountered during dental movements and palatal expansion. Objective: This study aims to evaluate the ability of PETG thermoplastic material to withstand deformation under functional and expansion forces, specifically within the context of orthodontic applications. Subjects and Methods: To estimate the firmness of the screw within the appliance, a universal Instron testing machine was used to record the forces released by each activation of the expander within the upper part of 10 clear modified twin blocks (MTBs) made from PETG and compare it with that released by 10 conventional twin blocks (CTBs). On the other hand, to determine the ability of the thermoplastic appliance to withstand the deformation during functional forces, a three‐point bending test was used to investigate the response of both appliances under static loading. Independent samples t ‐test was used to compare the differences between groups. Results: Both CTB and MTB groups follow the same pattern of increase and decrease in the amount of mean load with the CTB group line showing a considerably higher amount of mean load reaching the peak (334.5 N) at turn 25 of screw activation while the peak of mean load for MTB group was equal to 252.6 N at turn 23. There was a statistically significant difference between the CTB and MTB groups in the three‐point bending test ( p = 0.001). However, both appliances did not deform at the required force. Conclusions: The MTB can withstand both required expansion and functional load without deformation. Trial Registration: ClinicalTrials.gov identifier: NCT06116500 .