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The global plastic production has steadily increased from 1.7 million tons in 1950 to over 400 million tons in 2022, with about 60% of plastic ultimately ending up in landfills and oceans. There is also growing evidence that microplastics exert negative effects on biota and ecosystems. Biodegradable plastics may represent a safe alternative, yet their potential adverse effects have not been comprehensively analyzed. Here, we reviewed biodegradable plastics, with focus on their conversion into microplastics, their interactions with pollutants, and their combined toxicity for aquatic biota. Biodegradable plastics include polylactic acid, polyhydroxyalkanoates, polybutylene succinate, poly(butylene adipate-co-terephthalate), and poly(ε-caprolactone). We found that some biobased plastics are hardly biodegradable. Some biobased plastics are compostable but require specific environmental conditions for their biodegradation. Biobased plastics can generate microplastics when released into the environment, which can impact biota. Contrary to the common public belief, biodegradable plastics may not only originate from biosources but can be synthesized from fossil fuels. Microplastics originating from biodegradable plastics can interact with pollutants, adsorbing and transporting these pollutants, resulting in synergistic or antagonistic effects on exposed organisms. Biofilm formation on microplastics impacts their degradation and pollutant interactions. [ABSTRACT FROM AUTHOR]

Rationale: Plastic mulch film manages weed growth and moisture loss on the surface of cropping beds. The chemical components of such plastics include polymer(s), additives and non‐intentionally added substances (NIASs). The unknown chemical nature and behaviours of these constituents require investigation due to their potential to add to the anthropogenic chemical burden in the agrifood system. Methods: Solvent extracts of a commercial 15% polylactic acid (PLA)/85% poly(butylene adipate‐co‐terephthalate) mulch film were investigated using gas chromatography–mass spectrometry (GC–MS) with electron ionisation to characterise the additive and NIAS components. The obscurity of some of the NIASs meant their identification was not readily achieved through routine MS library comparisons. As such, the identification of several polymer‐derived compounds required interpretation of the MS data and re‐application of the derived fragmentation patterns with reference to the wider literature. Unknowns were confirmed using commercially available compounds. Results: Unknown NIASs were identified as cyclic oligoesters comprised of the monomeric building blocks of the polymer system. Cyclic structures derived from the monomers of polybutylene adipate (PBA) and polybutylene terephthalate (PBT) fragmented through a primary pathway involving 1,5‐ and 1,3‐H transfers at ester linkages. Characteristic ions at m/z 111, 129, 183 and 201 for PBA‐derived cyclic oligoesters and m/z 104, 132, 149 and 221 for PBT‐derived cyclic oligoesters were assigned in the mass spectra of unknowns. Cyclic oligoesters containing sebacate moieties were also identified, indicating the presence of polybutylene sebacate as an unexpected component of the mulch. Conclusions: Systematic analyses of the sort reported here are valuable for providing alternative approaches for the identification of plastic‐related chemicals. Open publication of MS spectral data is required to build a greater understanding of the mulch film chemical components contributing to the environmental chemical load introduced to agroecosystems. [ABSTRACT FROM AUTHOR]

The synthesis of conventional plastics has increased tremendously in the last decades due to rapid industrialization, population growth, and advancement in the use of modern technologies. However, overuse of these fossil fuel-based plastics has resulted in serious environmental and health hazards by causing pollution, global warming, etc. Therefore, the use of microalgae as a feedstock is a promising, green, and sustainable approach for the production of biobased plastics. Various biopolymers, such as polyhydroxybutyrate, polyurethane, polylactic acid, cellulose-based polymers, starch-based polymers, and protein-based polymers, can be produced from different strains of microalgae under varying culture conditions. Different techniques, including genetic engineering, metabolic engineering, the use of photobioreactors, response surface methodology, and artificial intelligence, are used to alter and improve microalgae stocks for the commercial synthesis of bioplastics at lower costs. In comparison to conventional plastics, these biobased plastics are biodegradable, biocompatible, recyclable, non-toxic, eco-friendly, and sustainable, with robust mechanical and thermoplastic properties. In addition, the bioplastics are suitable for a plethora of applications in the agriculture, construction, healthcare, electrical and electronics, and packaging industries. Thus, this review focuses on techniques for the production of biopolymers and bioplastics from microalgae. In addition, it discusses innovative and efficient strategies for large-scale bioplastic production while also providing insights into the life cycle assessment, end-of-life, and applications of bioplastics. Furthermore, some challenges affecting industrial scale bioplastics production and recommendations for future research are provided. [ABSTRACT FROM AUTHOR]

Polylactic acid (PLA), a biomass material, has garnered increasing interest as a biodegradable alternative for the production of eco-friendly plastics. Accordingly, the sustainable synthesis of lactic acid (LA) and its derivatives from biomass sources is emerging as a viable approach. In this work, an In-TS-1 zeolite with exceptional catalytic activity and stability was successfully synthesized using a hydrothermal method and applied for the efficient one-pot conversion of fructose into methyl lactate (MLA). Characterization of the resulting catalysts, including pyridine-adsorbed Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, ultraviolet-visible diffuse reflectance spectroscopy, and energy dispersive X-ray spectroscopy for elemental mapping, confirmed that the uniform dispersion of indium (In) species contributed to its favorable acidity and significantly boosted the reaction efficiency. Under optimized reaction conditions, a remarkable MLA yield of 71.9% was achieved upon the complete conversion of fructose. The selectivity of MLA remained consistent over 14 cycles, underscoring its extraordinary stability under hydrothermal conditions attributed to the confinement of In species within the zeolite framework. This research technique establishes a potential strategy for the large-scale manufacture of LA and its esters, offering a sustainable and efficient path for the development of biodegradable plastics. [ABSTRACT FROM AUTHOR]

The improper disposal of plastics is a growing concern due to increasing global environmental problems such as the rise of CO2 emissions, diminishing petroleum sources, and pollution, which necessitates the research and development of biodegradable materials as an alternative to conventional packaging materials. The purpose of this research was to analyse the properties of biodegradable polymer blends of thermoplastic potato starch (TPS) and polylactide, (PLA) without and with the addition of citric acid (CA) as a potential compatibilizer and plasticizer. The prepared blends were subjected to a comprehensive physicochemical characterization, which included: FTIR-ATR spectroscopy, morphological analysis by scanning electron microscopy (SEM), determination of thermal and mechanical properties by differential scanning calorimetry (DSC), water vapour permeability (WVP), as well as biodegradation testing in soil. The obtained results indicate an improvement in adhesion between the TPS and PLA phases due to the addition of citric acid, better homogeneity of the structure, and greater compatibility of the polymer blends, leading to better thermal, mechanical and barrier properties of the studied biodegradable TPS/PLA polymer blends. After conducting the comprehensive research outlined in this paper, it has been determined that the addition of 5 wt.% of citric acid serves as an effective compatibilizer and plasticizer. This supplementation achieves an optimal equilibrium across thermal, mechanical, morphological, and barrier properties, while also promoting material sustainability through biodegradation. In conclusion, it can be stated that the use of thermoplastic starch in TPS/PLA blends accelerates the biodegradation of PLA as a slowly biodegradable polymer. While the addition of citric acid offers significant advantages for TPS/PLA blends, further research is needed to optimize the formulation and processing parameters to achieve the desired balance between mechanical strength, thermal and barrier properties and biodegradability. [ABSTRACT FROM AUTHOR]

The increased use of plastics in industrial and agricultural applications has led to high levels of pollution worldwide and is a significant challenge. To address this plastic pollution, conventional methods such as landfills and incineration are used, leading to further challenges such as the generation of greenhouse gas emissions. Therefore, increasing interest has been directed to identifying alternative methods to dispose of plastic waste from agriculture. The novelty of the current research arose from the lack of critical reviews on how 3-Dimensional (3D) printing was adopted for recycling plastics, its application in the production of agricultural plastics, and its specific benefits, disadvantages, and limitations in recycling plastics. The review paper offers novel insights regarding the application of 3D printing methods including Fused Particle Fabrication (FPF), Hot Melt Extrusion (HME), and Fused Deposition Modelling (FDM) to make filaments from plastics. However, the methods were adopted in local recycling setups where only small quantities of the raw materials were considered. Data was collected using a systematic review involving 39 studies. Findings showed that the application of the 3D printing methods led to the generation of agricultural plastics such as Polylactic Acid (PLA), Acrylonitrile Butadiene Styrene (ABS), Polyethylene Terephthalate (PET), and High-Density Polyethylene (HDPE), which were found to have properties comparable to those of virgin plastic, suggesting the viability of 3D printing in managing plastic pollution. However, limitations were also associated with the 3D printing methods; 3D-printed plastics deteriorated rapidly under Ultraviolet (UV) light and are non-biodegradable, posing further risks of plastic pollution. However, UV stabilization helps reduce plastic deterioration, thus increasing longevity and reducing disposal. Future directions emphasize identifying methods to reduce the deterioration of 3D-printed agricultural plastics and increasing their longevity in addition to UV stability. [ABSTRACT FROM AUTHOR]

Plastic containers, commonly produced from non-biodegradable petroleum-based plastics such as polyethylene (PE), polypropylene (PP), and polyethylene terephthalate (PET), raise significant environmental concerns due to their persistence. The disposal of agricultural waste, specifically rice straw (RS), through burning, further compounds these environmental issues. In response, this study explores the integration of polylactic acid (PLA), a biodegradable material, with RS using a twin-screw extruder and injection process, resulting in the creation of a biodegradable packaging material. The inclusion of RS led to a decrease in the melt flow rate, thermal stability, and tensile strength, while concurrently enhancing the hydrophilic properties of the composite polymers. Additionally, the incorporation of maleic anhydride (MA) contributed to a reduction in the water absorption rate. The optimized formulation underwent migration testing and met the standards for food packaging products. Furthermore, no MA migration was detected from the composite. This approach not only provides a practical solution for the disposal of RS, but also serves as an environmentally-friendly alternative to conventional synthetic plastic waste. [ABSTRACT FROM AUTHOR]

Biodegradable plastics, represented by polylactic acid (PLA), are considered suitable alternatives to nondegradable commodity plastics; however, their degradation through microbial decomposition is seen as a waste of carbon resources and inevitably brings about CO2 emission. Alternatively, waste PLA plastics can be utilized as feedstocks for the sustainable production of value-added chemicals, which not only avoids a carbon footprint but also realizes upcycling of plastic waste. Here, we show a cascade system that combines alkali-induced depolymerization, pulsed electrooxidation, and electrochemical reductive amination to produce alanine with an overall yield of 69% under near ambient conditions. Specifically, we first implement an alkali catalyst in an aqueous solution to depolymerize PLA into lactate. The obtained PLA hydrolysate is directly utilized as both feedstock and electrolyte for pyruvate production over a nickel hydroxide-supported Pd electrocatalyst (Pd/Ni(OH)2) via a pulsed potential, which is followed by the transformation of pyruvate into alanine using a TiO2 catalyst. This cascade process for alanine production benefits from high efficiencies maintained in three consecutive processes, mild operation conditions, and the use of cost-effective feedstocks (plastic wastes), without suffering harsh conditions and expensive feedstock consumption required by conventional biological and chemical approaches for alanine synthesis, respectively. [ABSTRACT FROM AUTHOR]

Biocomposites were fabricated utilizing polylactic acid (PLA) combined with native starch sourced from mountain's yam (Dioscorea remotiflora Knuth), an underexplored tuber variety. Different starch compositions (7.5, 15.0, 22.5, and 30.0 wt.%) were blended with PLA in a batch mixer at 160 °C to produce PLA/starch biocomposites. The biocomposites were characterized by analyzing their morphology, particle size distribution, thermal, X-ray diffraction (XDR), mechanical, and dynamic mechanical (DMA) properties, water absorption behavior, and color. The results showed that the amylose content of Dioscorea remotiflora starch was 48.43 ± 1.4%, which corresponds to a high-amylose starch (>30% of amylose). Particle size analysis showed large z-average particle diameters (Dz0) of the starch granules (30.59 ± 3.44 μm). Scanning electron microscopy (SEM) images showed oval-shaped granules evenly distributed throughout the structure of the biocomposite, without observable agglomeration or damage to its structure. XDR and DMA analyses revealed an increase in the crystallinity of the biocomposites as the proportion of the starch increased. The tensile modulus (E) underwent a reduction, whereas the flexural modulus (Eflex) increased with the amount of starch incorporated. The biocomposites with the highest Eflex were those with a starch content of 22.5 wt.%, which increased by 8.7% compared to the neat PLA. The water absorption of the biocomposites demonstrated a higher uptake capacity as the starch content increased. The rate of water absorption in the biocomposites followed the principles of Fick's Law. The novelty of this work lies in its offering an alternative for the use of high-amylose mountain's yam starch to produce low-cost bioplastics for different applications. [ABSTRACT FROM AUTHOR]

Graphene oxide nanosheet (GO) is a multifunctional platform for binding with nanoparticles and stacking with two dimensional substrates. In this study, GO nanosheets were sonochemically decorated with zinc oxide nanoparticles (ZnO) and self-assembled into a hydrogel of GO–ZnO nanocomposite. The GO–ZnO hydrogel structure is a bioinspired approach for preserving graphene-based nanosheets from van der Waals stacking. X-ray diffraction analysis (XRD) showed that the sonochemical synthesis led to the formation of ZnO crystals on GO platforms. High water content (97.2%) of GO–ZnO hydrogel provided good property of ultrasonic dispersibility in water. Ultraviolet-visible spectroscopic analysis (UV–vis) revealed that optical band gap energy of ZnO nanoparticles (∼3.2 eV) GO–ZnO nanosheets (∼2.83 eV). Agar well diffusion tests presented effective antibacterial activities of GO–ZnO hydrogel against gram-negative bacteria (E. coli) and gram-positive bacteria (S. aureus). Especially, GO–ZnO hydrogel was directly used for brush painting on biodegradable polylactide (PLA) thin films. Graphene-based nanosheets with large surface area are key to van der Waals stacking and adhesion of GO–ZnO coating to the PLA substrate. The GO–ZnO/PLA films were characterized using photography, light transmittance spectroscopy, coating stability, scanning electron microscopy (SEM), energy-dispersive x-ray spectroscopic mapping (EDS), antibacterial test and mechanical tensile measurement. Specifically, GO–ZnO coating on PLA substrate exhibited stability in aqueous food simulants for packaging application. GO–ZnO coating inhibited the infectious growth of E. coli biofilm. GO–ZnO/PLA films had strong tensile strength and elastic modulus. As a result, the investigation of antibacterial GO–ZnO hydrogel and GO–ZnO coating on PLA film is fundamental for sustainable development of packaging and biomedical applications. [ABSTRACT FROM AUTHOR]

Consumers, companies, and governments are becoming more interested in compostable materials as the amount of waste generated from single-use petrochemical-based and non-biodegradable plastics has grown exponentially since 1960. A drawback to compostable flexible option films is the lack of equivalent moisture barrier performance to maintain a comparable shelf life of food products compared with traditional petrochemical-based versions. Stereocomplex PLA (SC-PLA), a combination of the stereoisomers L -PLA (PLLA) and D -PLA (PDLA), offers a potential solution to this problem. This study presents a viable and novel method to cast extrude SC-PLA films without using a masterbatch. For comparison, several blend compositions were produced, including 85/15, 70/30, 50/50, and 30/70 PLLA/PDLA and homocomplex PLLA and PDLA films. The samples were then annealed at 160 °C for 5, 15, and 30 min to understand the effect on the crystallinity (Xc), moisture vapor permeability coefficient (MVPC), and functional and mechanical performance. As expected, the Xc increased for all the samples upon annealing. We observed increased crystallization kinetics in the blended samples, which crystallized in 5 minutes, which can be ascribed to the nucleation effect, while the PLLA and PDLA started crystallizing between 15 and 30 minutes. PDLA acted as a nucleating agent at levels as low as 15% to induce crystallization in ≤5 minutes in the blended samples. We observed a correlation between the crystallization trend of various compositions and MVPC, with the blended annealed films having a significantly better moisture barrier than all the non-annealed films. The increased Xc reduces the strength properties due to higher brittleness associated with the higher Xc. Further optimization is needed to produce fully viable films for commercial applications; however, this work shows pathways to unlock the creation of PLA films with high barriers to water. [ABSTRACT FROM AUTHOR]

An increase in plastic waste pollution and the strengthening of global environmental policies have heightened the need for research on biodegradable plastics. In this regard, polylactic acid (PLA) and poly(butylene adipate-co-terephthalate) (PBAT) are notable examples, serving as alternatives to traditional plastics. In this study, the compatibility and mechanical properties of PLA/PBAT blends were improved by the chemical grafting of maleic anhydride (MAH). In addition, qualitative analyses were conducted, dynamic mechanical properties were investigated, and the structure and mechanical characteristics of the blends were analyzed. With an increase in the MAH concentration, the grafting yield of the blends increased, and significantly improved the compatibility of the PLA/PBAT blend, with an ~2 and 2.9 times increase in the tensile strength and elongation at break, respectively. These findings indicate that the modified PLA/PBAT blend demonstrates potential for applications that require sustainable plastic materials, thereby contributing to the development of environmentally friendly alternatives in the plastics industry. [ABSTRACT FROM AUTHOR]

The consumption of synthetic, non-biodegradable polymer plastics has drawn attention to growing environmental concerns, prompting the development of other materials, particularly bio-based materials. Biopolymer-based biocomposite materials are plasticized to improve their ductility. In this study, five distinct weight ratios of biopolymers (PA/EOO), 90 wt.%, 80 wt.%, 70 wt.%, 60 wt.%, and 50 wt.% were employed as plasticizers for poly-lactic acid (PA) in a fluid molding process. The mechanical, thermal stability, and morphological characteristics of the blends were each examined using a viscometer measurement (R.V.), tensile properties (TP), a scanning electron microscope (SEM), and a thermogravimetric analyzer (TGA). All composite materials (PA/EOO) mixtures show notable improvements in mechanical properties and excellent thermal stability when compared to pure PA. The maximum PA/EOO elongation at break was around 213 % when the PA/EOO mix was 80 wt %. Attractive morphological results from composite materials (PA/EOO) blends showed that EOO was compatible with PA and that the resulting composite material (PA/EOO) was thought to be an ecologically beneficial mixture because it contained vegetable oil. [ABSTRACT FROM AUTHOR]

Global warming has led to a high incidence of extreme heat events, and the frequent occurrence of extreme heat events has had extensive and far-reaching impacts on wetland ecosystems. The widespread distribution of plastics in the environment, including polyethylene (PE), polylactic acid (PLA), and tire particles (TPs), has caused various environmental problems. Here, high-throughput sequencing techniques and metabolomics were used for the first time to investigate the effects of three popular microplastic types: PE, PLA, and TP, on the sediment microbiome and the metabolome at both temperatures. The microplastics were incorporated into the sediment at a concentration of 3% by weight of the dry sediment (wt/wt), to reflect environmentally relevant conditions. Sediment enzymatic activity and physicochemical properties were co-regulated by both temperatures and microplastics producing significant difference s compared to controls. PE and PLA particles inhibited bacterial diversity at low temperatures and promoted bacterial diversity at high temperatures, and TP particles promoted both at both temperatures. For bacterial richness, only PLA showed inhibition at low temperature; all other treatments showed promotion. PE, PLA, and TP microplastics changed the community structure of sediment bacteria, forming two clusters at low and high temperatures. Furthermore, PE, PLA, and TP changed the sediment metabolic profiles, producing differential metabolites such as lipids and molecules, organic heterocyclic compounds, and organic acids and their derivatives, especially TP had the most significant effect. These findings contribute to a more comprehensive understanding of the potential impact of microplastic contamination. [ABSTRACT FROM AUTHOR]

This study investigates the suitability of using caffeine-treated and untreated black cherry (Prunus serotina Ehrh.) wood as a polylactide filler. Composites containing 10%, 20%, and 30% filler were investigated in terms of increasing the nucleating ability of polylactide, as well as enhancing its resistance to microorganisms. Differential scanning calorimetry studies showed that the addition of caffeine-treated wood significantly altered the crystallization behavior of the polymer matrix, increasing its crystallization temperature and degree of crystallinity. Polarized light microscopic observations revealed that only the caffeine-treated wood induced the formation of transcrystalline structures in the polylactide. Incorporation of the modified filler into the matrix was also responsible for changes in the thermal stability and decreased hydrophilicity of the material. Most importantly, the use of black cherry wood treated with caffeine imparted antifungal properties to the polylactide-based composite, effectively reducing growth of Fusarium oxysporum, Fusarium culmorum, Alternaria alternata, and Trichoderma viride. For the first time, it was reported that treatment of wood with a caffeine compound of natural origin alters the supermolecular structure, nucleating abilities, and imparts antifungal properties of polylactide/wood composites, providing promising insights into the structure-properties relationship of such composites. [ABSTRACT FROM AUTHOR]

Huge amounts of plastic products are produced, utilized, and discarded each year, contributing to the increasingly serious ecological problem. Photoreforming, a solar-driven technology, provides an uncomplicated route to simultaneously recycle plastics and facilitate hydrogen (H 2) production. Herein, we proposed innovative CdS/NiS composites which used visible light to drive H 2 evolution from plastic wastes. Results confirmed that the loading of NiS on CdS could facilitate the transmission of photoexcited electrons, which greatly improved the photocatalytic performance. The H 2 production capability of CdS/NiS was more than 6 times higher than that of pure CdS, and the highest H 2 yield reached 62.9 mmol g−1 h−1 under optimized conditions when polylactic acid (PLA) was treated. Typical polyester plastics, including polyethylene terephthalate (PET), polybutylene adipate (PBA), polybutylene terephthalate (PBT), and poly (butyleneadipate-co-terephthalate) (PBAT), as well as raw PLA drink straws, were also successfully employed as the hole scavenger to enhance H 2 generation. This system utilized abundant resources (solar energy and waste plastics) and worked under mild conditions, proffering a sustainable approach for H 2 synthesis together with waste plastic pollutant reduction for a carbon-neutral future. [Display omitted] • CdS/NiS composite photocatalyst was used for visible-light-driven H 2 generation. • Various polyester plastics were employed as feedstocks to produce H 2 and organics. • The highest H 2 yield reached 62.9 mmol g−1 h−1 when polylactic acid was used. • The hydroxyl-containing monomers worked as hole scavengers in the reaction process. • The reaction mechanism of waste plastics photo-reforming over CdS/NiS was proposed. [ABSTRACT FROM AUTHOR]

For decades, plastic waste management has been one of the major ecological challenges of our society. Despite the introduction of biodegradable alternatives such as polylactic acid (PLA), their beneficial environmental impact is limited by the requirement of specific compost facility as biodegradation of PLA in natural environment occurs at a very slow rate. In this work, a plastic-degrading enzyme was utilized to facilitate degradation process. Genomic and proteomic tools were employed to identify a new biodegradable plastic-degrading enzyme from Cryptococcus nemorosus TBRC2959. The new enzyme, Cr14CLE, functions optimally under mild conditions with temperature range of 30 to 40 °C and suffers no significant loss of enzymatic activity at pH ranging from 6 to 8. In addition to PLA, Cr14CLE is capable to degrade other types of biodegradable plastic such as polybutylene succinate (PBS) and polybutylene adipate terephthalate (PBAT) as well as composite bioplastic. Applications of Cr14CLE have been demonstrated through the preparation of enzyme-coated PLA film and laminated PLA film with enzyme layer. PLA films prepared by both approaches exhibited capability to self-degrade in water. Key points: • Novel plastic-degrading enzyme (Cr14CLE) was identified and characterized. • Cr14CLE can degrade multiple types of biodegradable plastics under mild conditions. • Applications of Cr14CLE on self-degradable plastic were demonstrated. [ABSTRACT FROM AUTHOR]

Poly(hydroxybutyrate-co-hidroxyvalerate) (PHBV) is a biodegradable polymer, which is a potential substitute for plastics made from fossil resources. Due to its practical interest in the field of tissue engineering, packaging, sensors, and electronic devices, the demand for PHBV with specific thermal, electrical, as well as mechanical requirements is growing. In order to improve these properties, we have developed PHBV blends with two thermoplastic biodegradable polyesters, including poly(caprolactone) (PCL) and poly(lactic acid) (PLA). We analysed the effect of these biopolymers on the morphological, wetting, structural, thermal, mechanical, and electrical characteristics of the materials. Further, the biodegradation of the samples in simulated body fluid conditions was evaluated, as well as the antibacterial activity. The results demonstrate that the blending with PCL and PLA leads to films with a dense morphology, increases the hydrophilic character, and induces a reinforcement of the mechanical characteristics with respect to pristine PHBV. In addition, a decrease in dielectric constant and a.c. electrical conductivity was noticed for PHBV/PLA and PHBV/PCL blends compared to neat PHBV polymer. All neat polymers and blends showed antibacterial properties against S. aureus, with more than 40% bacterial reduction, which increased to 72% in the presence of PCL polymer for a blend ratio of 50/50. Thus, it is demonstrated a suitable way to further tailor a variety of functionalities of PHBV for specific applications, by the development of polymer blends with PLA or PCL. [ABSTRACT FROM AUTHOR]

Biodegradable plastics are attracting attention as a solution to the problems caused by plastic waste. Among biodegradable plastics, polylactide (PLA) and poly (butylene succinate) (PBS) are particularly noteworthy because of their excellent biodegradability. However, the drawbacks of their mechanical properties prompts the need to compound them to achieve the desired strength. The characteristics of the interface of the composite material determine the realization of its final performance. The study of the interface and microstructure of composites is essential for the development of products from degradable polymers. The morphology evolution and microcrystal structure of spin-casted fully biodegradable (PLA/PBS) blend films were investigated using atomic force microscopy (AFM)-based nanomechanical mapping. Results show that intact blend films present an obvious phase separation, where the PBS phase is uniformly dispersed in the PLA phase in the form of pores. Furthermore, the size and number of the PBS phase have a power exponential relationship and linear relationship with PBS loading, respectively. Intriguingly, after annealing at 80 °C for 30 min, the PLA phase formed an orderly petal-like microcrystalline structure centered on the PBS phase. Moreover, the microcrystalline morphology changed from a "daisy type" to a "sunflower type" with the increased size of the PBS phase. Since the size of the PBS phase is controllable, a new method for preparing microscopic patterns using fully biodegradable polymers is proposed. [ABSTRACT FROM AUTHOR]

Biodegradable polymers have emerged as fascinating materials due to their non-toxicity, environmentally benign nature and good mechanical strength. The toxic effects of non-biodegradable plastics paved way for the development of sustainable and biodegradable polymers. The engineering of biodegradable polymers employing various strategies like radical ring opening polymerization, enzymatic ring opening polymerization, anionic ring opening polymerization, photo-initiated radical polymerization, chemoenzymatic method, enzymatic polymerization, ring opening polymerization and coordinative ring opening polymerization have been discussed in this review. The application of biodegradable polymeric nanoparticles in the biomedical field and cosmetic industry is considered to be an emerging field of interest. However, this review mainly highlights the applications of selected biodegradable polymers like polylactic acid, poly(ε-caprolactone), polyethylene glycol, polyhydroxyalkanoates, poly(lactide-co-glycolide) and polytrimethyl carbonate in various fields like agriculture, biomedical, biosensing, food packaging, automobiles, wastewater treatment, textile and hygiene, cosmetics and electronic devices. [ABSTRACT FROM AUTHOR]

This study presents the extrusion process while using a single-screw extruder and polylactide (PLA). This material belongs to the so-called biodegradable plastics, and is characterized by a higher density compared to typical polymeric materials used to manufacture products in this technology. Various polyethylenes and polypropylenes and their derivatives are commonly used. An evaluation of the extrusion process was carried out for various extruder operating parameters. The rotational speed of the screw and the process temperature were changed. For each rotational speed of the screw, the following readings were made: changes in temperature, active power, current intensity, pressure, and mass of extruded plastics each time. [ABSTRACT FROM AUTHOR]

Polylactic acid nanoparticles (PLA NPs) according to food and drug administration are biodegradable and biocompatible polymers that have received a lot of attention due to their natural degradation mechanism. Although there is already available information concerning the effects of PLA microplastic to aquatic organisms, the knowledge about PLA NPs is still vague. In the present study, we analyzed the chemical composition of engineered PLA NPs, daily used PLA items and their breakdown products. We show that PLA breakdown products are oxidized and may contain aldehydes and/or ketones. The breakdown produces nanosized particles, nanoplastics, and possibly other small molecules as lactide or cyclic oligomers. Further, we show that all PLA breakdown nanoplastics extended the survival rate in Daphnia magna in an acute toxicity assay, however, only PLA plastic cup breakdown nanoplastics showed a significant difference compared to a control group. [ABSTRACT FROM AUTHOR]

Background: Although three years after the outbreak of SARS-CoV-2, the virus is still having a significant impact on human health and the global economy. Infection through respiratory droplets is the main transmission route, but the transmission of the virus by surface contact cannot be ignored. Hand sanitizers and antiviral films can be applied to control SARS-CoV-2, but sanitizers and films show drawbacks such as resistance of the virus against ethanol and environmental problems including the overuse of plastics. Therefore, this study suggested applying natural substrates to hand sanitizers and antiviral films made of biodegradable plastic (PLA). This approach is expected to provide advantages for the easy control of SARS-CoV-2 through the application of natural substances. Methods: Antiviral disinfectants and films were manufactured by adding caffeic acid and vanillin to ethanol, isopropyl alcohol, benzalkonium chloride, and PLA. Antiviral efficacies were evaluated with slightly modified international standard testing methods EN 14,476 and ISO 21,702. Results: In suspension, all the hand sanitizers evaluated in this study showed a reduction of more than 4 log within 2 min against HCoV-229E. After natural substances were added to the hand sanitizers, the time needed to reach the detection limit of the viral titer was shortened both in suspension and porcine skin. However, no difference in the time needed to reach the detection limit of the viral titer was observed in benzalkonium chloride. In the case of antiviral films, those made using both PLA and natural substances showed a 1 log reduction of HCoV-229E compared to the neat PLA film for all treatment groups. Furthermore, the influence of the organic load was evaluated according to the number of contacts of the antiviral products with porcine skin. Ten rubs on the skin resulted in slightly higher antiviral activity than 50 rubs. Conclusion: This study revealed that caffeic acid and vanillin can be effectively used to control HCoV-229E for hand sanitizers and antiviral films. In addition, it is recommended to remove organic matter from the skin for maintaining the antiviral activity of hand sanitizer and antiviral film as the antiviral activity decreased as the organic load increased in this study. [ABSTRACT FROM AUTHOR]

To improve the toughness and heat resistance of polylactic acid (PLA), polybutylene succinate (PBS) was sufficiently blended with PLA as the base matrix, and the glass fiber (GF) that was modified with 3-aminopropyltriethoxysilane (KF-GF) was added as the reinforcement. The results demonstrated a noteworthy boost in both mechanical and heat resistance properties when employing KH-GF, in comparison to pristine GF. When the content of KH-GF reached 20%, the tensile, flexural, and IZOD impact strength of the composites were 65.53 MPa, 83.43 MPa, and 7.45 kJ/m2, respectively, which were improved by 123%, 107%, and 189% compared to the base matrix, respectively. This enhancement was primarily attributed to the stronger interfacial adhesion between KH-GF and the PLA/PBS matrix. Furthermore, the Vicat softening temperature of the composites reached 128.7 °C, which was a result of increased crystallinity. In summary, the incorporation of KH-GF into PLA/PBS composites resulted in notable enhancements in their mechanical properties, crystallinity, and thermal characteristics. The high performance KH-GF-reinforced PLA/PBS composite showed a broad application potential in the field of biodegradable packaging, biodegradable textiles, and biodegradable plastic bags. [ABSTRACT FROM AUTHOR]

For much of the Caribbean region, plastic pollution and the persistence of the great Atlantic Sargassum belt lead to significant regional loss in biodiversity, employment and tourism. Yet, seaweeds such as Sargassum possess all the characteristics for bioplastic production. This study presents a new process on the production of biodegradable calcium alginate (Ca(Alg)2) composite bioplastic, and evaluates its economic feasibility and environmental impact in the Caribbean, compared to bio-based polylactic acid (PLA) and synthetic plastics (PET). Our cradle-to-gate life cycle impact assessment (LCIA) shows normalized (kg CO2eq per kg plastic) greenhouse gas (GHG) impacts 3 to 7 times higher for the baseline alginate composite process over those of PLA and PET films – linked mainly to chemical consumption. However, through the integration of abundant bioenergy from the local paper industry and the nascent E-methanol (E-MeOH) supply chains, GHG impact reduces by 79% – illustrating a pathway to a sustainable bioplastic production flowsheet. More attractively, the alginate bioplastic outperforms in providing ultra-low oxygen barrier packaging properties – with a required mass of plastic material producing a total carbon footprint (kg CO2eq) 64–978 times lower than PLA and PET respectively, and overall packaging costs 280 times less than current synthetic plastic. Techno-economics illustrate that a total annualized cost (TAC) for alginate bioplastic of $US 4.56 per kg is possible, ensuring high economic feasibility, comparable to current commercial bio-based alternatives. Moreover, sensitivity analysis highlights that variability in TAC was mainly associated with sodium alginate utilization in the manufacture process – contributing up to 67% to the overall cost. In light of this, the integration of sound policies aligned to improved consumer awareness and reduced plastic waste can help to drive greater economic feasibility of the alginate bioplastic industry. Ultimately, our study illustrates a viable and sustainable alginate bioplastic alternative, promoting and informing on packaging innovation while achieving low carbon operations within the Caribbean plastic sector. [ABSTRACT FROM AUTHOR]

With the gradual depletion of petroleum resources and the increasing global awareness of environmental protection, biodegradable plastics are receiving more and more attention as a green substitute for traditional petroleum-based plastics. Poly (lactic acid) is considered to be the most promising biodegradable material because of its excellent biodegradability, biocompatibility, and good processability. However, the brittleness and high cost limit its application in more fields. Lignin, as the second largest renewable biopolymer in nature after cellulose, is not only rich in reserves and low in cost, but it also has an excellent UV barrier, antioxidant activity, and rigidity. The molecular structure of lignin contains a large number of functional groups, which are easy to endow with new functions by chemical modification. Currently, lignin is mostly treated as waste in industry, and the value-added utilization is insufficient. The combination of lignin and poly (lactic acid) can on the one hand solve the problems of the high cost of PLA and less efficient utilization of lignin; on the other hand, the utilization of lignocellulosic biomass in compounding with biodegradable synthetic polymers is expected to afford high-performance wholly green polymer composites. This mini-review summarizes the latest research achievements of poly (lactic acid)/lignin composites. Emphasis was put on the influence of lignin on the mechanical properties of its composite with poly (lactic acid), as well as the compatibility of the two components. Future research on these green composites is also prospected. [ABSTRACT FROM AUTHOR]

Polylactide (PLA) has become a popular alternative for petroleum-based plastics to reduce environmental pollution. The broader application of PLA is hampered by its brittle nature and incompatibility with the reinforcement phase. The aim of our work was to improve the ductility and compatibility of PLA composite film and investigate the mechanism by which nanocellulose enhances PLA polymer. Here, we present a robust PLA/nanocellulose hybrid film. Two different allomorphic cellulose nanocrystals (CNC-I and CNC-III) and their acetylated products (ACNC-I and ACNC-III) were used to realize better compatibility and mechanical performance in a hydrophobic PLA matrix. The tensile stress of the composite films with 3% ACNC-I and ACNC-III increased by 41.55% and 27.22% compared to pure PLA film, respectively. Compared to the CNC-I or CNC-III enhanced PLA composite films, the tensile stress of the films increased by 45.05% with 1% ACNC-I and 56.15% with 1% ACNC-III. In addition, PLA composite films with ACNCs showed better ductility and compatibility because the composite fracture gradually transitioned to a ductile fracture during the stretching process. As a result, ACNC-I and ACNC-III were found to be excellent reinforcing agents for the enhancement of the properties of polylactide composite film, and the replacement some petrochemical plastics with PLA composites would be very promising in actual life. [ABSTRACT FROM AUTHOR]

• Impact assessment of alkaline pretreatment on bioplastics methanization via BMP. • The methanization rate of tested bioplastics was improved by alkaline pretreatment. • Carbon solubilization due to pretreatment and methanization were material dependent. • PLA and the PLA/PCL blend were only mesophilically digested when pretreated. The effect of alkali-based pretreatment on the methanization of bioplastics was investigated. The tested bioplastics included PHB [poly(3-hydroxybutyrate)], PHBH [poly(3-hydroxybutyrate-co-3-hydroxyhexanoate)], PHBV [poly(3-hydroxybutyrate-co-3-hydroxyvalerate], PLA (polylactic acid), and a PLA/PCL [poly(caprolactone)] 80/20 blend. Prior to methanization tests, the powdered polymers (500–1000 μm) at a concentration of 50 g/L were subjected to alkaline pretreatment using NaOH 1 M for PLA and PLA/PCL, and NaOH 2 M for PHB-based materials. Following 7 days of pretreatment, the amount of solubilized carbon for PLA and its blend accounted for 92–98% of the total initial carbon, while lower carbon recoveries were recorded for most PHB-based materials (80–93%), as revealed by dissolved total organic carbon analysis. The pretreated bioplastics were then tested for biogas production by means of mesophilic biochemical methane potential tests. Compared to unpretreated PHBs, methanization rates of pretreated PHBs were accelerated by a factor of 2.7 to 9.1 with comparable (430 NmL CH 4 /g material feed) or slightly lower (15% in the case of PHBH) methane yields, despite featuring a 1.4–2.3 times longer lag phases. Both materials, PLA and the PLA/PCL blend, were only extensively digested when pretreated, yielding about 360–380 NmL CH 4 per gram of material fed. Unpretreated PLA-based materials showed nearly zero methanization under the timeframe and experimental conditions tested. Overall, the results suggested that alkaline pretreatment can help to enhance the methanization kinetics of bioplastics. [ABSTRACT FROM AUTHOR]

We present a spectrophotometric-based assay to identify enzymes that degrade commercially available bioplastics. Bioplastics comprise aliphatic polyesters with hydrolysis-susceptible ester bonds and are proposed as a replacement for petroleum-based plastics that accumulate in the environment. Unfortunately, many bioplastics can also persist in environments including seawater and waste centers. Our assay involves an overnight incubation of candidate enzyme(s) with plastic, followed by A610 spectrophotometry using 96-well plates to quantify both a reduction in residual plastic and the liberation of degradation by-products. We use the assay to show that Proteinase K and PLA depolymerase, two enzymes that were previously shown to degrade pure polylactic acid plastic, promote a 20–30% breakdown of commercial bioplastic during overnight incubation. We validate our assay and confirm the degradation potential of these enzymes with commercial bioplastic using established mass-loss and scanning electron microscopy methods. We show how the assay can be used to optimize parameters (temperature, co-factors, etc.) to enhance the enzyme-mediated degradation of bioplastics. The assay endpoint products can be coupled with nuclear magnetic resonance (NMR) or other analytical methods to infer the mode of enzymatic activity. Overall, the screening capacity of the spectrophotometric-based assay was demonstrated to be an accurate method to identify bioplastic-degrading enzymes. [ABSTRACT FROM AUTHOR]

Global pollution by plastics derived from petroleum has fostered the development of carbon–neutral, biodegradable bioplastics synthesized from renewable resources such as modern biomass, yet knowledge on the impact of bioplastics on ecosystems is limited. Here we review the polylactic acid plastic with focus on synthesis, biodegradability tuning, environmental conversion to microplastics, and impact on microbes, algae, phytoplankton, zooplankton, annelids, mollusk and fish. Polylactic acid is a low weight semi-crystalline bioplastic used in agriculture, medicine, packaging and textile. Polylactic acid is one of the most widely used biopolymers, accounting for 33% of all bioplastics produced in 2021. Although biodegradable in vivo, polylactic acid is not completely degradable under natural environmental conditions, notably under aquatic conditions. Polylactic acid disintegrates into microplastics faster than petroleum-based plastics and may pose severe threats to the exposed biota. [ABSTRACT FROM AUTHOR]

The resistance of plastic textiles to environmental degradation is of major concern as large portions of these materials reach the ocean. There, they persist for undefined amounts of time, possibly causing harm and toxicity to marine ecosystems. As a solution to this problem, many compostable and so-called biodegradable materials have been developed. However, to undergo rapid biodegradation, most compostable plastics require specific conditions that are achieved only in industrial settings. Thus, industrially compostable plastics might persist as pollutants under natural conditions. In this work, we tested the biodegradability in marine waters of textiles made of polylactic acid, a diffused industrially compostable plastic. The test was extended also to cellulose-based and conventional non-biodegradable oil-based plastic textiles. The analyses were complemented by bio-reactor tests for an innovative combined approach. Results show that polylactic acid, a so-called biodegradable plastic, does not degrade in the marine environment for over 428 days. This was also observed for the oil-based polypropylene and polyethylene terephthalate, including their portions in cellulose/oil-based plastic blend textiles. In contrast, natural and regenerated cellulose fibers undergo complete biodegradation within approximately 35 days. Our results indicate that polylactic acid resists marine degradation for at least a year, and suggest that oil-based plastic/cellulose blends are a poor solution to mitigate plastic pollution. The results on polylactic acid further stress that compostability does not imply environmental degradation and that appropriate disposal management is crucial also for compostable plastics. Referring to compostable plastics as biodegradable plastics is misleading as it may convey the perception of a material that degrades in the environment. Conclusively, advances in disposable textiles should consider the environmental impact during their full life cycle, and the existence of environmentally degradable disposal should not represent an alibi for perpetuating destructive throw-away behaviors. [ABSTRACT FROM AUTHOR]

The objective of this research was to investigate the mechanical, physical and antibacterial activities and biodegradability properties of bioplastics from polylactic acid (PLA) and corncob fibers (CF). The bioplastics were prepared by mixing PLA and CF at different ratios (100:0, 90:10, 80:20, 70:30, 60:40 and 50:50 % w:w) in the internal mixer and molding was done by using the hot-compressing molding method. The results demonstrated the decrease in tensile strength and elongation at break with increased in CF. Young’s modulus was found to be highest in the 70 %PLA: 30 %CF bioplastic, however, it decreased when the CF was increased. The hardness and water absorption were dependent on CF concentration. SEM analysis revealed the well dispersion of CF in PLA matrix. PLA matrix and increasing of CF induced in CF agglomeration. To develop PLA/CE plastic for antibacterial food packaging application, its antibacterial activity was conducted. The antibacterial determination revealed that 70 %PLA: 30 %CF containing 2 % TiO2 bioplastic exhibited the highest inhibition against E. Coli, S. aureus and B. subtilis. Additionally, the biodegradable character of the bioplastic was dependent on concentration and time, as the bioplastic weight loss was increased when the concentration of CF and biodegradation period were increased. The results obtained from this research indicate that the bioplastics prepared from polylactic acid and corncob fibers is biodegradable bioplastics and can be used as alternate synthetic plastics. The bioplastic with 2 %TiO2 added can be utilized potentially for expected antibacterial food packaging. [ABSTRACT FROM AUTHOR]

3D Plastronics is a technology capable of improving the integration of heterogeneous functions in or on polymer packages of electronic devices by implementation of conductive patterns and electronic components. Among 3D Plastronics technologies, In-Mold Electronics (IME) is a fast-growing emerging manufacturing process for mass production of plastronic devices. It is based on the screen printing of a thermoplastic film (printed electronic process), followed by a 3D shaping using thermoforming and finally a step of overmolding by injection of a thermoplastic polymer. Nowadays, IME is mainly based on PolyCarbonate (PC), which is thus a reference material. The paper focuses on Poly(Lactic Acid) (PLA), a biosourced and biodegradable polymer to reduce the environmental impact of IME manufacturing. The thermal and mechanical properties of the PLA materials are investigated to optimize the IME process parameters and to take into account the glass transition temperature Tg around 55–60 °C of PLA. Thermal properties of inks are then considered to adapt drying to the polymer substrate, with the results being a good adhesion (category 0 of the ISO 2409 standard) and sufficient electrical resistivity (290 µΩ.cm) of the ink on PLA. Electronic components are connected to the circuit with conductive and structural pastes giving a shear stress of 9.1 N/mm2 on PLA. The next steps of the IME process are also studied, thermoforming and injection molding. An electronic circuit is designed as a demonstration vehicle combining the IME process with PLA as the main structural material. [ABSTRACT FROM AUTHOR]

Plants, animals, bacteria, and food waste are subjects of intensive research, as they are biological sources for the production of biopolymers. The topic links to global challenges related to the extended life cycle of products, and circular economy objectives. A severe and well-known threat to the environment, the non-biodegradability of plastics obliges different stakeholders to find legislative and technical solutions for producing valuable polymers which are biodegradable and also exhibit better characteristics for packaging products. Microorganisms are recognized nowadays as exciting sources for the production of biopolymers with applications in the food industry, package production, and several other fields. Ubiquitous organisms, lactic acid bacteria (LAB) are well studied for the production of exopolysaccharides (EPS), but much less as producers of polylactic acid (PLA) and polyhydroxyalkanoates (PHAs). Based on their good biodegradability feature, as well as the possibility to be obtained from cheap biomass, PLA and PHAs polymers currently receive increased attention from both research and industry. The present review aims to provide an overview of LAB strains' characteristics that render them candidates for the biosynthesis of EPS, PLA, and PHAs, respectively. Further, the biopolymers' features are described in correlation with their application in different food industry fields and for food packaging. Having in view that the production costs of the polymers constitute their major drawback, alternative solutions of biosynthesis in economic terms are discussed. [ABSTRACT FROM AUTHOR]

A biodegradable blend of PBAT—poly(butylene adipate-co-terephthalate)—and PLA—poly(lactic acid)—for blown film extrusion was modified with four multi-functional chain extending cross-linkers (CECL). The anisotropic morphology introduced during film blowing affects the degradation processes. Given that two CECL increased the melt flow rate (MFR) of tris(2,4-di-tert-butylphenyl)phosphite (V1) and 1,3-phenylenebisoxazoline (V2) and the other two reduced it (aromatic polycarbodiimide (V3) and poly(4,4-dicyclohexylmethanecarbodiimide) (V4)), their compost (bio-)disintegration behavior was investigated. It was significantly altered with respect to the unmodified reference blend (REF). The disintegration behavior at 30 and 60 °C was investigated by determining changes in mass, Young's moduli, tensile strengths, elongations at break and thermal properties. In order to quantify the disintegration behavior, the hole areas of blown films were evaluated after compost storage at 60 °C to calculate the kinetics of the time dependent degrees of disintegration. The kinetic model of disintegration provides two parameters: initiation time and disintegration time. They quantify the effects of the CECL on the disintegration behavior of the PBAT/PLA compound. Differential scanning calorimetry (DSC) revealed a pronounced annealing effect during storage in compost at 30 °C, as well as the occurrence of an additional step-like increase in the heat flow at 75 °C after storage at 60 °C. The disintegration consists of processes which affect amorphous and crystalline phase of PBAT in different manner that cannot be understood by a hydrolytic chain degradation only. Furthermore, gel permeation chromatography (GPC) revealed molecular degradation only at 60 °C for the REF and V1 after 7 days of compost storage. The observed losses of mass and cross-sectional area seem to be attributed more to mechanical decay than to molecular degradation for the given compost storage times. [ABSTRACT FROM AUTHOR]

This review appraised current research on enzyme-embedded biodegradable agricultural plastics and microbial degradation, given that the increased use of fossil-fuel-based plastics in agriculture involved significant environmental tradeoffs. Over 370 million tons of plastics were produced in 2019, releasing over 400 million tons of greenhouse gases during production, transportation, consumption, burning, and exposure to sunlight biodegradation. Less than 10% of bags are recycled at the end of their life, leading to environmental pollution. Thus, it is imperative to summarize studies that have suggested solutions of this problem. The scoping review approach was preferred, given that it established current practices and uncovered international evidence on bio-based solutions and conflicting outcomes. Bioplastics with low greenhouse warming potential had a small market share (approximately 1%). The accumulation of fossil-fuel-based plastics and poor post-use management releases mercury, dioxins, furans, and polychlorinated biphenyls (PCBs). Enzyme-embedded polymers degrade fast in the environment but lack the desired mechanical properties. Even though polylactic acid (PLA) and other bioplastics are better alternatives to synthetic polymers, they persist in the environment for years. Fast degradation is only practical under special conditions (elevated temperatures and humidity), limiting bioplastics' practical benefits. The research and development of plastics that could degrade under ambient conditions through enzyme-catalyzed reactions and soil-inoculated microbes are ongoing. However, there are no guarantees that the technology would be profitable in commercial agriculture. Other limiting factors include the geographical disparities in agricultural plastic waste management. Future perspectives on the waste management of agricultural plastics require smart technologies, such as artificial intelligence (AI), machine learning (ML), and enzyme-embedded plastics that degrade under ambient conditions. The replacement of synthetic plastics with polylactic acid and polycaprolactone/Amano lipase (PCL/AL) composite films would offset the negative ecological effects. A major drawback was the slow research and development and commercial adoption of bio-based plastics. The transition to bioplastics was resource- and time-intensive. [ABSTRACT FROM AUTHOR]

The increasing concerns about plastic pollution and climate change have encouraged research into bioderived and biodegradable materials. Much attention has been focused on nanocellulose due to its abundance, biodegradability, and excellent mechanical properties. Nanocellulose-based biocomposites are a viable option to fabricate functional and sustainable materials for important engineering applications. This review addresses the most recent advances in composites, with a particular focus on biopolymer matrices such as starch, chitosan, polylactic acid, and polyvinyl alcohol. Additionally, the effects of the processing methods, the influence of additives, and the outturn of nanocellulose surface modification on the biocomposite's properties are outlined in detail. Moreover, the change in the composites' morphological, mechanical, and other physiochemical properties due to reinforcement loading is reviewed. Further, mechanical strength, thermal resistance, and the oxygen–water vapor barrier properties are enhanced with the incorporation of nanocellulose into biopolymer matrices. Furthermore, the life cycle assessment of nanocellulose and composites were considered to analyze their environmental profile. The sustainability of this alternative material is compared through different preparation routes and options. [ABSTRACT FROM AUTHOR]

The raw material of polylactide (PLA) is lactic acid obtained by biological fermentation. PLA is the most promising degradable polymer to replace traditional plastics to address the pollution problems caused by their non-degradability. However, the application of PLA is hindered by its low softening temperature, easy hydrolysis, and poor toughness. Herein, the ternary composites with PLLA, PDLA and Poly (butylene adipate- co -terephthalate) (PBAT) were prepared by melt blending to balance its thermal stability, hydrolysis, and toughness. The effects of PBAT content (3 %, 6 %, 9 % and 12 %) and isothermal crystallization temperature on composite properties were fully investigated. The results show that the composite of stereo-complexed PLA (sc-PLA) with 6 % PBAT crystallized at 110 °C exhibits good comprehensive properties. Its vicat softening temperature (VST), mass loss rate under alkaline (pH = 12) and breaking elongation are 166 °C, 21.6 % and 4.40 %, respectively. Compared with the pure PLLA sample crystallized at same condition, the VST, mass loss rate and breaking elongation are 159 °C, 24.7 % and 3.76 % respectively, which increased by nearly 5 %, 13 % and 20 %. This indicates that this strategy is feasible to balance the heat resistance, hydrolysis resistance and toughness of PLA, while it sacrifices the tensile strength a little. This work provides a new way to modify and improve the PLA properties. Nonetheless, it is also necessary to coordinate the compatibility of PLA and PBAT. [ABSTRACT FROM AUTHOR]

Global warming and plastic pollution result from the massive use of fossil fuels, calling for the development of sustainable bioplastics derived from modern biomass. Bioplastic production is expected to increase to 2.43 million tons globally in 2024. In particular, the production of biopolymers from bioresources and organic waste should highly reduce waste accumulation. Biopolymers can be produced by employing microbes or by using monomers from agro-resources. Here we review the use of lignin and polylactic acid for polymer production using enzymes and microorganisms. Carnobacterium, Enterococcus and Aspergillus niger show high lactic acid productivity of about 0.4–1.4 g/L/h. Lignin and polylactic acid can also be transformed into value-added chemicals such as muconic acid, hydrouronic acid, adipic acid and terephthalic acid. [ABSTRACT FROM AUTHOR]

Bioplastics are one of the answers to environmental pollution and linear material flows. The most promising bioplastic polylactide (PLA) is already replacing conventional plastics in a number of applications. The properties of PLA, however, do not fit for all potential application areas, but they can be altered by the introduction of comonomers. The copolymerization of lactide (LA) with other lactones like ϵ‐caprolactone (CL) has been established for several years. Nevertheless, controlling copolymerizations remains a challenge due to the high complexity of the system. Copolymerization of LA with other monomer classes is much less investigated, but has the chance to overcome the limitations in material properties that occur when only lactones are used. The crucial factor for all copolymerizations is the catalyst. It dominates the reaction kinetics and determines the resulting microstructure. In this review, copolymerization catalysts for LA are presented divided into catalysts for the synthesis of lactone block copolymers, lactone random copolymers, and multimechanistically synthesized copolymers. The selected catalysts are highlighted either owing to their industrially applicable polymerization conditions or their non‐standard mechanism. [ABSTRACT FROM AUTHOR]

But, in jute-soy sapling pot, the growing roots easily came out of the pot wall (Figure 9f) indicating better degradation of jute-soy pot as compared to other containers after 30 days. Keywords: Seedling pot; biodegradation; natural fiber; mechanical properties; jute; soy resin; ; ; ; ; ; ; EN Seedling pot biodegradation natural fiber mechanical properties jute soy resin ZH 7738 7749 12 11/21/22 20221220 NES 221220 Introduction The rising concern of day-to-day increment in consumption of nondegradable plastic and environmental issues led to researcher think about natural fiber-reinforced composites and their chance to overcome the above issue. Weight loss of MJS composites after different biodegradation periods Scanning electron microscopy SEM micrographs of jute sapling pot (MJS7) before and after 30, 60, and 90 days of sapling under soil are shown in Figure 8. [Extracted from the article]

Microplastics are hazardous to aquatic life. Most experiments focus on the effects of a single type of microbead, while in the environment, organisms are exposed to irregularly shaped fragments belonging to several chemical groups. The effects of biodegradable plastics are unknown. We tested the effects of mixed-source (MS) petroleum-based and biodegradable (polylactic acid, PLA) microplastics on the intertidal eastern mudsnail, Ilyanassa obsoleta (Say, 1822), a benthic grazer. MS plastics were collected from local coastal areas (polystyrene, polyethylene, polypropylene, polyvinyl chloride and polyethylene terephthalate, combined) and were tested at three exposures, including one similar to concentrations found locally (2250 particles/kg sediment). Plastics were milled to be similar in size to the biofilm–sediment mix provided to the snails as food (32.94 µm2 for sediment, 137.99 µm2 for MS, and 31.16 µm2 for PLA). Locally relevant exposures of MS microplastics disrupted digestive gland histology, while extreme exposures additionally increased the number of hemocytes and reduced fecundity. Effects of PLA were similar to those of MS microplastics, at the extreme exposure tested here. These results indicate that both petroleum-based and biodegradable microplastics disrupt the structure of the digestive gland and that environmentally relevant exposures induce "hidden" tissue-level changes that are invisible without specialized techniques. [ABSTRACT FROM AUTHOR]

Stereocomplexation between enantiomeric poly(l -lactide) (PLLA) and poly(d -lactide) (PDLA) is a promising sustainable approach and gaining momentum to overcome the shortcomings of polylactide (PLA) for its use as a replacement for fossil-based plastics. Filler addition in tailoring the crystallization of stereocomplex PLA (SC-PLA) has attracted extensive attention; however, research has primarily focused on the heterogeneous nucleation effect of filler. The impact of filler on the chain behavior of SC-PLA during crystallization has not been exclusively discussed, and the rigid amorphous fraction (RAF) development remains unknown. In this study, the crystallization of PLLA/PDLA blends was modified by low loading of layered double hydroxide (LDH) (≤ 1 wt%) with the proposed local effect of such filler, and additional RAF development was incurred. In the early stage of crystallization, LDH facilitates the pairing of PLLA and PDLA and arrests the ordered SC pairs during the dynamic balance between the separation and pairing of racemic segments. This explains the severely suppressed homochiral (HC) crystallization, promoted SC crystallization, and additional RAF formation driven by the nucleation-induced chain ordering. This work, for the first time, highlights the role of LDH in creating SC-PLA with tailorable polymorphism and RAF, where the mechanism can be extended to other filler-type nucleator systems. [ABSTRACT FROM AUTHOR]

Polylactic acid-based (PLA) composites are widely used in biomedicine, electrical components, food packaging and other fields, but their unsatisfactory mechanical properties such as high brittleness and poor toughness, cause problems in functional applications. This work developed a green and environmentally friendly strategy to improve PLA mechanical properties. Flexible polybutylene succinate (PBS) and alkaline hydrogen peroxide (AHP) treated straw fibers (SF) synergistically modified PLA. AHP is decomposed into a large amount of HOO-, which oxidizes the hydroxyl groups in SF to carboxyl groups to obtain oxidized straw fiber (OSF), which reacts with PLA in the molten state to form new ester bonds. The tensile strength of the OSF/PLA composite is 41.78 MPa, 38 % higher than the SF/PLA composite. The impact toughness of OSF/PBS/PLA composite is 14.47 KJ/m2 increased by 54 % after the adding PBS, while the tensile strength was also better than the control group. The synergistic action of PLA and PBS in OSF is attributed to the formation of new chemical bonds, efficient crystallization, and compatible interface. This study provides a new strategy to produce fiber-reinforced PLA composites with good toughness. It takes positive significance for developing degradable plastics with good performance and controllable cost. • Oxidized straw fiber successfully strengthens modified polylactic acid. • A green composite with good impact resistance and tensile properties is prepared. • The synergistic modification mechanism of OSF and PBS on PLA is explored. [ABSTRACT FROM AUTHOR]

Polylactide (PLA) is one of the most attractive bioplastics as it can be produced from nontoxic renewable feedstock. However, its inherently poor toughness greatly limits its large-scale application. Cost-effectively toughening PLA without sacrificing its transparency remains a big challenge. We herein prepared an imidazolium-based poly(ionic liquid)- b -PLA copolymer (ILA) and ionomers as toughening agent for PLA through an integrative approach including continuous-monomer-feeding copolymerization, quaternization reaction, ion exchange and inter-ionomers blending. By blending PLA with the ILA and ionomers, we successfully obtained PLA materials with combined features including high toughness, good transparency and antibacterial properties. The effects of regulated ionomer composition and ILA compatibilizer on phase morphology, mechanical properties and transparency of the blends were systematically studied. The optimum formulation (PLA/E12/ILA 60/40/5) shows an impressive transmittance of 89–93 %, high impact strength of 45 kJ/m2 and elongation at break at 170 %, which are about 17 and 24 times that of pure PLA, respectively. More interestingly, the presence of imidazolium cation and anion groups endows the blends with attractive antibacterial properties. Ion exchange between ILA copolymer and the imidazolium-containing ionomeric system leads to a synergistic effect of compatibilization and efficient toughening, providing a new strategy for develop high performance PLA materials. [Display omitted] • A novel block copolymer compatibilizer was prepared for PLA/ionomer blends. • The toughening agents with desirable modulus and T g were designed by blending ionomers based on dynamic anion exchange. • PLA blends with the well-designed toughening agents exhibit excellent toughness, transparency and antibacterial property. [ABSTRACT FROM AUTHOR]

As the demand for PLA increases, post-consumer disposal strategies must be carefully considered. While we would love to embrace a bioplastic future, we also need to tread carefully. Though PLA is widely claimed to be biodegradable, full degradation often requires conditions not typically found in landfills or industrial composting. Therefore, it will negatively impact the environment if treated carelessly. In this work, we report a simple PLA upcycling path to turn existing PLA wastes into new 3D printable materials within 48 hours. The ester bonds of PLA can be cleaved efficiently via aminolysis. The obtained monomeric compound was derivatized with methacrylic anhydride, which introduces double bonds and thus a cross-linkable monomer is obtained. In combination with a comonomer and initiator, a photocurable resin is produced. The resin can be fed into any commercially available photocuring 3D printer. The 3D printed parts derived from PLA wastes exhibit impressive performances with a tensile strength of 58.6 MPa, Young's modulus of 2.8 GPa, and glass transition at ∼180 °C. Our work demonstrates a new route to active upcycling of PLA while minimizing the need for disposal. [ABSTRACT FROM AUTHOR]

To promote the sustainable development of society, it is important to develop methods for facile fabrication of bio‐based plastics that are mechanically robust and capable of recycling and completely degrading in soil. In this study, such bio‐based supramolecular plastics are conveniently and cost‐effectively fabricated by cross‐linking epoxidized soybean oil (ESO) and low‐molecular‐weight polylactic acid (PLA) (≈2 kDa) with dynamic boroxines. The bio‐based supramolecular plastic, which is denoted as ESO‐PLA, exhibits a tensile strength of ≈43 MPa and is highly flexible and water‐resistant. After being stored in an environment with a 100% relative humidity for 10 days, the tensile strength of the plastic remains higher than polyethylene. Due to the reversibility of boroxines, the ESO‐PLA plastic can be conveniently processed into different shapes and products. Meanwhile, the plastic can be recycled multiple times for repeated usage by either hot‐pressing or solvent‐assisted depolymerization/repolymerization methods. Benefiting from the easy degradation of ESO and low‐molecular‐weight PLA, the breakage of boroxine cross‐links enables rapid and complete degradation of the plastics in soil within 60 days. Additionally, in vitro and in vivo tests prove that the ESO‐PLA plastic exhibits satisfactory biocompatibility, which extends its application in medicine, food, and cosmetics industries. [ABSTRACT FROM AUTHOR]