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Pollution from plastics is a major issue in the current context, prompting the scientific community to focus its efforts on recycling these materials. Mechanical recycling emerges as the most popular due to its practicality and cost‐effectiveness. In fact, with the increase in environmental awareness, the adoption of new circular economy models, stricter regulations mandating disposal and recycling, and lower costs compared to other recycling techniques, this type of recycling is taking a predominant role over other method. However, the presence of a variety of products of different polymeric nature, the introduction of new biodegradable products, and the complexity of multilayer packaging combining different polymers, without concrete solutions for recycling create a heterogeneous range of materials that leaks into the environment. The scientific literature is actively addressing these challenges, and this review aims to explore the latest strategies for enhancing the mechanical recycling of new and challenging polymer systems. Specifically, it explores the recycling of materials originally designated for landfill, incineration or composting, focusing on advancements in management of these previously overlooked and problematic system. This underexplored perspective seeks to offer new insights and innovative solutions that can transform polymer waste management and advance more sustainable recycling practices. [ABSTRACT FROM AUTHOR]

Nowadays, plastic contamination worldwide is a concerning reality that can be addressed with appropriate society education as well as looking for innovative polymeric alternatives based on the reuse of waste and recycling with a circular economy point of view, thus taking into consideration that a future world without plastic is quite impossible to conceive. In this regard, in this review, we focus on sustainable polymeric materials, biodegradable and bio-based polymers, additives, and micro/nanoparticles to be used to obtain new environmentally friendly polymeric-based materials. Although biodegradable polymers possess poorer overall properties than traditional ones, they have gained a huge interest in many industrial sectors due to their inherent biodegradability in natural environments. Therefore, several strategies have been proposed to improve their properties and extend their industrial applications. Blending strategies, as well as the development of composites and nanocomposites, have shown promising perspectives for improving their performances, emphasizing biopolymeric blend formulations and bio-based micro and nanoparticles to produce fully sustainable polymeric-based materials. The Review also summarizes recent developments in polymeric blends, composites, and nanocomposite plasticization, with a particular focus on naturally derived plasticizers and their chemical modifications to increase their compatibility with the polymeric matrices. The current state of the art of the most important bio-based and biodegradable polymers is also reviewed, mainly focusing on their synthesis and processing methods scalable to the industrial sector, such as melt and solution blending approaches like melt-extrusion, injection molding, film forming as well as solution electrospinning, among others, without neglecting their degradation processes. [ABSTRACT FROM AUTHOR]

A new polyol derived from gamma-valerolactone with 10 carbon chain and four hydroxyl groups was used in combination with choline chloride for the production of a deep eutectic solvent (DES) employed as plasticizer for chitosan. The polyol estimated boiling point was 340 °C and the glass transition temperature (Tg) was − 6 °C. No crystallization temperature was observed due to the non-symmetric structure of polyol and because it is a mixture of stereoisomers. A eutectic condition was detected in an interval of choline chloride(ChCl)/polyol composition from 2:1 to 1:10. It was observed that only the mixtures with higher ChCl content showed melting points, so the eutectic composition was chosen by the lowest Tg that was obtained by the 1:1 molar ratio mixture, circa − 40 °C. This ChCl/Polyol composition was used to prepare plasticized chitosan film, by hot pressing. The glycerol/choline chloride mixture was also used as DES for comparison purposes. Both DES acted as plasticizer to obtain chitosan thermoplastic films, verified by the significant Tg drop from 165 °C, for unplasticized film, to -2 °C and − 30 °C, for films plasticized with DES based on ChCl-polyol and ChCl-glycerol, respectively. The materials plasticized with ChCl-polyol, showed a decrease in modulus of about 54% and an increase of 455% in elongation compared to ChCl/Glycerol, indicating better plasticization efficiency of the polyol based DES. The use of ChCl/Polyol have opened up a new opportunity for the use of chitosan as a plastic material and the high boiling point of polyol has made it a real and highly stable plasticizer. [ABSTRACT FROM AUTHOR]

Biodegradable polymers, particularly Polyhydroxyalkanoates (PHAs) and their derivatives, have garnered increasing attention across diverse industries owing to their distinct advantages such as bio-based sourcing, biocompatibility, and impressive biodegradability performance. Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) is one of the most attractive members of PHAs with a great potential to replace conventional non-biodegradable polymers. However, one critical drawback restricting PHBV usage is its thermal instability, which could bring about a narrow processing window, especially for conventional melt processing methods such as injection molding. Moreover, the high crystallinity and slow nucleation rate make PHBV brittle, leading to poor mechanical performance. This study incorporated epoxidized natural rubbers (ENR-25 and ENR-50) into PHBV through a melt blending process to enhance PHBV toughness and flexibility. Incorporation of 5wt% polybutadiene grafted maleic anhydride (PB-g-MA) as a compatibilizer notably enhances mechanical properties. Furthermore, the study introduces the concept of thermoplastic vulcanizate (TPV) through melt blending using dynamic vulcanization (DV) to enhance mechanical properties, particularly the toughness of the 70/30 PHBV/ENR blends, identified as the optimal blending ratio based on prior research. The resulting blend vulcanizate (PHBV/ENRv) exhibits toughness values of 63.0 ± 14.8 J m− 1 and 24.4 ± 2.8 J m− 1 for blends with ENRv-25 and ENRv-50, respectively. These findings hold promise for advancing the design and development of biodegradable polymer blend systems, with a focus on enhancing processability and mechanical performance. [ABSTRACT FROM AUTHOR]

Nanofiber membranes receive considerable interest recently because of their distinctive structural features, facile preparation, as well as high filtering efficiency. Due to ever‐increasing air pollution, membranes made from biodegradable materials can play a crucial part in providing purified air with minimum concerns of environmental issues after the membrane's end of service life. The purpose of this systematic review is to assess the performance of biodegradable electrospun nanofibrous membrane filters toward air sub‐micron particles. To identify relevant studies, a systematic search is carried out in major scientific search engines including PubMed, Scopus, and the Web of Science. Data extraction is used to collect the necessary information on the membranes' structural properties, as well as filtration performance metrics such as efficiency, pressure drop, and quality factor. Among the electrospun membranes derived from biodegradable polymers, the polyvinyl alcohol (PVA)‐based electrospun membranes are more effective in filtration efficiency in capturing sub‐micron particles. The results highlight that these types of membranes are effective in filtration with low energy consumption, making them more apt for air purification. The use of such membranes can supply both high filtering performance and protection of the environment. [ABSTRACT FROM AUTHOR]

Biodegradable polymers are gaining attention as alternatives to non‐biodegradable plastics to address environmental issues. With the rising global demand for plastic products, the development of non‐toxic, biodegradable plastics is a significant topic of research. Aliphatic polyester, the most common biodegradable polyester, is notable for its semi‐crystalline structure and can be synthesized from fossil fuels, microbial fermentation, and plants. Due to great properties like being lightweight, biodegradable, biocompatible, and non‐toxic, aliphatic polyesters are used in packaging, medical, agricultural, wearable devices, sensors, and textile applications. The biodegradation rate, crucial for biodegradable polymers, is discussed in this review as it is influenced by their structural properties and environmental conditions. This review discusses currently available biodegradable polyesters, their emerging applications, and the challenges in their commercialization. As research in this area grows, this review emphasizes the innovation in biodegradable aliphatic polyesters and their role in advancing environmental sustainability. [ABSTRACT FROM AUTHOR]

Transdermal drug delivery has been an increasingly studied alternative drug administration route owing to the large surface area of the skin, enabling ease of access and application. Among the various transdermal drug delivery technologies that have been developed so far, microarray patches (MAPs) incorporating microneedle technology (MN) have garnered much attention. MAPs can easily penetrate the stratum corneum, facilitating the delivery of desired substances directly into the skin, exhibiting a higher delivery efficiency compared to alternative transdermal drug delivery approaches. The effectiveness of MAPs in delivering therapeutics is affected by a multitude of factors, one of which is the selection of materials employed in their fabrication. Among various materials that have been used to fabricate MAPs, synthetic biodegradable polymers such as poly(lactic‐co‐glycolic acid) (PLGA) and polylactic acid (PLA) have been exploited for sustained and controlled release with excellent biocompatibility. PLGA and PLA can be used to construct the entire needle shaft or drug‐loaded microparticles which are then incorporated into needle layer. The combination of MN technology in conjunction with biodegradable polymers has revolutionized sustained and controlled transdermal delivery of small and large molecules. [ABSTRACT FROM AUTHOR]

Background/Objectives: Microparticle-based drug delivery systems offer several advantages for protein-based drug formulations, enhancing patient compliance and therapeutic efficiency through the sustained delivery of the active pharmaceutical ingredient. Over the past few decades, the microfluidics method has emerged as a continuous manufacturing process for preparing drug-encapsulating microparticles, mainly for small molecule drugs. However, comparative assessments for the conventional batch method vs. the microfluidics method for protein-based drug formulations have been lacking. The main objective of this study was to generate immunomodulatory protein drug-loaded injectable formulations using both conventional batch and microfluidics methods. Methods: Therefore, rhCCL22-loaded poly(lactic-co-glycolic) acid (PLGA) microparticles were prepared by conventional homogenization and microfluidics methods. Results: The resulting microparticles were analyzed comparatively, focusing on critical quality attributes such as microparticle size, size distribution, morphology, drug encapsulation efficiency, release kinetics, and batch-to-batch variations in relation to the manufacturing method. Our results demonstrated that the conventional method resulted in microparticles with denser surface porosity and wider size distribution as opposed to microparticles prepared by the microfluidics method, which could contribute to a significant difference in the drug-release kinetics. Additionally, our findings indicated minimal variation within batches for the microparticles prepared by the microfluidics method. Conclusions: Overall, this study highlights the comparative assessment of several critical quality attributes and batch variations associated with the manufacturing methods of protein-loaded microparticles which is crucial for ensuring consistency in efficacy, regulatory compliance, and quality control in the drug formulation manufacturing process. [ABSTRACT FROM AUTHOR]

Materials engineering has become an important tool in the field of hydrogel dressings used to treat difficult-to-heal wounds. Hydrogels filled with bioactive substances used as a targeted healing system are worthy of attention. Vitamin C has healing and supporting effects in the treatment of many skin problems. The aim of the research was to produce a hydrogel biomaterial enriched with ascorbic acid for use as a dressing for difficult-to-heal wounds. A total of four different dressings were developed, each with different modifications in each layer. The dressing with vitamin C in the third layer was shown to release vitamin C ions more slowly than the dressing with vitamin C in the first layer. The studies conducted have shown that the dressings containing vitamin C have, among other things, a higher compressive strength, are characterised by a lower relative shortening after the application of force and shorten without damage at a lower force than in the case of a dressing without vitamin C. The dressings designed have a very good stability in the temperature range of 18 °C to 60 °C. It was found that the higher the vitamin C content in the dressing, the greater the increase in the specific heat value of the transformations. Therefore, hydrogel dressings containing vitamin C may be candidates for local delivery of vitamin C to the skin and protection of the wound area. [ABSTRACT FROM AUTHOR]

This review focuses on advancements in polymer science as it relates to three-dimensional (3D) and four-dimensional (4D) printing technologies, with a specific emphasis on applications in the biomedical field. While acknowledging the breadth of 3D and 4D printing applications, this paper concentrates on the use of polymers in creating biomedical devices and the challenges associated with their implementation. It explores integrative modeling and experimental insights driving innovations in these fields, focusing on sustainable manufacturing with biodegradable polymers, a comparative analysis of 3D and 4D printing techniques, and applications in biomedical devices. Additionally, the review examines the materials used in both 3D and 4D printing, offering a detailed comparison of their properties and applications. By highlighting the transformative potential of these technologies in various industrial and medical applications, the paper underscores the importance of continued research and development. The scope of this review also includes an overview of future research directions to address current challenges, enhance material capabilities, and explore practical applications. [ABSTRACT FROM AUTHOR]

Poly (butylene succinate) PBS is considered one of the most interesting biodegradable polymers because of the good compromise of mechanical strength, ductility, toughness, and impact resistance. To change the properties of PBS, modified poly (butylene succinate-co-butylene adipate-co-ethylene succinate-co-ethylene adipate) (PBEAS) was developed. Meanwhile, polylactide (PLA) is one of the commercially used eco-friendly polymers but is limited for commercial applications due to its brittleness and relatively slow hydrolysis. In this study, we explore potential synergistic effects of blending PLA with PBS and PLA with PBEAS, and their properties before and after hydrolytic degradations were investigated as a function of degradation time. [ABSTRACT FROM AUTHOR]

Poly(3-hydroxybutyrate) (PHB) is a microbially derived polyhydroxyalkanoate that is widely used in biomedical applications. In this study, we investigated the use of acetic acid (aa) as an alternative environmentally friendly solvent for the preparation of gels from PHB (PHB aa) and compared their characteristics with PHB products dissolved in chloroform (PHB chl) using such methods as DSC, FTIR, SEM, rheometry, biodegradation, and cytocompatibility assay. A slight decrease in the degree of the crystallinity of the PHB from 61% to 50.8% was found when the acetic acid was used. This resulted in a greater mass loss for the PHB aa (11%) during enzymatic degradation over 180 days. Gels prepared from PHB in the different solvents showed differences in the microstructure and porosity of the samples, which affected their viscoelastic properties. The storage modulus (G′) for the PHB aa gels was higher by 35% compared to that for the PHB chl, and Young's modulus in compression was 101.5 and 41.3 kPa for the PHB aa and PHB chl, respectively. The porosity of the PHB aa was 97.7%, which was 5.2% higher than that for the PHB chl. The presence of low molecular weight polymers in the PHB aa had an effect on mesenchymal stem cells' viability, expressed as a threefold increase in the number of attached cells after 7 days of incubation compared to the PHB chl. Thus, the proposed method of PHB-based materials' preparation is a promising, more environmentally friendly analog of the extensively used method of preparation from chloroform. [ABSTRACT FROM AUTHOR]

In light of the growing plastic waste problem worldwide, including in agriculture, this study focuses on the usefulness of both conventional, non-degradable plastics and environmentally friendly bioplastics in the agricultural sector. Although conventional plastic products are still essential in modern, even ecological agriculture, the increasing contamination by these materials, especially in a fragmented form, highlights the urgent need to search for alternative, easily biodegradable materials that could replace the non-degradable ones. According to the literature, polymers are widely used in agriculture for the preparation of agrochemicals (mostly fertilizers) with prolonged release. They also play a role as functional polymers against pests, serve as very useful super absorbents of water to improve crop health under drought conditions, and are commonly used as mulching films, membranes, mats, non-woven fabrics, protective nets, seed coatings, agrochemical packaging, or greenhouse coverings. This widespread application leads to the uncontrolled contamination of soil with disintegrated polymeric materials. Therefore, this study highlights the possible applications of bio-based materials as alternatives to conventional polyolefins or other environmentally persistent polymers. Bio-based polymers align with the strategy of innovative agricultural advancements, leading to more productive farming by reducing plastic contamination and adverse ecotoxicological impacts on aquatic and terrestrial organisms. On the other hand, advanced polymer membranes act as catching agents for agrochemicals, protecting against environmental intoxication. The global versatility of polymer applications in agriculture will not permit the elimination of already existing technologies involving polymers in the near future. However, in line with ecological trends in modern agriculture, more "green" polymers should be employed in this sector. Moreover, we highlight that more comprehensive legislative work on these aspects should be undertaken at the European Union level to guarantee environmental and climate protection. From the EU legislation point of view, the implementation of a unified, legally binding system on applications of bio-based, biodegradable, and compostable plastics should be a priority to be addressed. In this respect, the EU already demonstrates an initial action plan. Unfortunately, these are still projected directions for future EU policy, which require in-depth analysis. [ABSTRACT FROM AUTHOR]

Effective removal of ammonia, nitrate, and intermediate nitrite is a challenge faced by highly dissolved oxygen (DO) recirculating aquaculture systems (RAS). This study investigated the effect of DO concentrations (Group A, DO 3.15 ± 0.12 mg/L, Group B, DO 4.43 ± 0.15 mg/L, Group C, DO 6.52 ± 0.35 mg/L, Group D, and DO 7.86 ± 0.55 mg/L) on the simultaneous nitrification and denitrification (SND) of aquaculture seawater using poly (3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) as a biofilm carrier and solid-phase denitrification (SPD) carbon source. Ammonia and nitrate were simultaneously removed in all the PHBV-supported SPD systems. Ammonia in Group C had the highest removal rate (5.72 mg/(L·h)), whereas nitrate and nitrite in Group A were completely removed at 4 and 5 h, respectively. The continuous release of PHBV provided carbon sources for denitrification. High throughout sequencing showed that Proteobacteria, Bacteroidetes, Desulfobacterota, and Chloroflexi at the phylum level, and Marinobacter, Shewanella, and Pseudomonas at the genus level exhibited unique relative abundances under varying DO concentrations. The nitrification genes in Group C showed the highest expression. Denitrification genes in Group A were enriched. The relative expression of nitrogen-transforming genes further demonstrated the results for water quality and the microbial community. DO concentration affected the efficiency of the nitrogen transformation pathway in the PHBV-supported SPD system. [ABSTRACT FROM AUTHOR]

Driven by population growth, rising living costs, and the urgent need to address climate change, sustainable food production and circular economy principles are becoming increasingly important. Conventional agriculture faces significant challenges, including land scarcity, water shortages, and disrupted supply chains. As a solution, cities are adopting vertical farming to enhance urban food security and promote circularity. This research introduces FLOAT (Farming Lab on a Trough), an innovative vertical farming system made from bio-polymers and recycled polyethylene terephthalate glyco (rPETG) pellets from plastic bottles. FLOAT's design emphasizes sustainability and closed-loop material usage. The study showcases the versatility of additive manufacturing (AM) in creating complex geometries with fully functional 1:1 prototypes. These prototypes highlight FLOAT's potential as a scalable and adaptable solution for sustainable food production in urban settings, contributing to improved food security and environmental sustainability. By integrating FLOAT with conventional practices, we aim to exceed Singapore's 2030 food security targets and achieve lasting urban food resilience. FLOAT aims to scale sustainable food production, fostering community ties with food, and nurturing future responsibility. [ABSTRACT FROM AUTHOR]

Phosvitin shows chelating abilities, an affinity for ACTH (corticotropin), growth factors, antioxidant properties, and acidic nature. An attempt was made to use this protein in hydrogels as a transporter of other protein substances: somatotropin (STH) and (ACTH). The aim of the study was to evaluate the effect of phosvitin on the permeation of ACTH and STH from semi-solid forms of the drug applied to the skin. Four hydrogel substrates were prepared using natural polymers: sodium alginate, methylcellulose, and starch. Based on the evaluation of physicochemical parameters, the hydrogel with the most favorable properties was selected and loaded with the active substances STH and ACTH, followed by the addition of phosvitin. A study of the permeation of STH and ACTH through the artificial cellulose membrane and through porcine skin was carried out without and with the addition of phosvitin. The effect of protein substances on rheological and textural parameters was studied. The evaluation of physicochemical parameters showed a favorable effect of STH and Phosvitin on the stability of the hydrogel with 4% methylcellulose and no effect of ACTH. All prepared formulations showed a reaction close to the natural pH of human skin. In the porcine skin permeation study, the addition of Phosvitin to the hydrogel with STH caused a slight increase in the amount of STH permeated and an increase in the time for STH to permeate porcine skin by 30 min. Phosvitin caused an increase in the amount of ACTH permeated through porcine skin almost twofold. Phosvitin may prove to be a promising permeation promoter for model protein-peptide substances when applied to the skin surface. [ABSTRACT FROM AUTHOR]

Gynecological malignancies are the main factors that seriously endanger the life and health of women worldwide. Chemotherapy is one of the traditional methods for the treatment of gynecological malignancies. Conventional chemotherapeutic drugs used in medicine have shortcomings, such as poor target tissue-specific distribution, high toxicity, and side effects. They are prone to problems such as tumor recurrence, invasion, metastasis, and drug resistance. The rapid development of nano-drug delivery systems achieves attenuation, potentiation, inhibition of metastasis, and resistance to drug resistance, bringing hope for the treatment of gynecological malignancies. This article briefly summarizes novel nano-drug delivery systems based on biodegradable polymers and their mediated treatment strategy for gynecological tumors to provide a theoretical basis for developing and clinically translating nano-drug delivery systems for gynecological malignancies. [ABSTRACT FROM AUTHOR]

Metal oxide-infused polymer composites with higher dielectric constants are emerging as compelling solutions for effective Electromagnetic Interference shielding (EMIS) applications. In this work, hybrid polymer blends were made of polyoxy methane (POM) and polyvinyl alcohol (PVA), using the conventional solution casting method. This study investigated the dielectric properties of the polymer blend by adding different concentrations (1 to 4 wt.%) of titanium dioxide (TiO2) nanofillers that are synthesized via combustion technique with egg albumen. It is evident from the crystallite size of the TiO2 nanoparticles that the egg albumen not only acted as a fuel but also acted as a capping agent in preventing the agglomeration of the particles thereby controlling the size. Increased nanofiller decreased the crystallinity of the polymer blend. The composite with 3 wt.% TiO2 exhibits the highest dielectric constant (1385) and electromagnetic shielding effectiveness. Further, the developed hybrid nanocomposites exhibit excellent shielding effectiveness in the frequency range of 8 to 12 GHz. The uniqueness of this study lies in the cost-effective preparation of nanocomposites with a very less concentration of TiO2 nanoparticles. These nanocomposite films could be a potential replacement for films infused with carbon black, multiwalled carbon nanotubes, graphene oxide and nickel oxide nanofillers, etc. [ABSTRACT FROM AUTHOR]

Ginger (Zingiber officinale) extract was encapsulated in maltodextrin/modified starch with spray drying. Composition of maltodextrin and composition of modified starch were chosen as mixture components (0%, 5%, 10%, 15%, and 20% (w/v)), while process factor was inlet air temperature (135 °C, 150 °C, and 165 °C). I-optimal design under combined study type was selected for design of the experiments, modeling, and optimization. The optimum conditions were achieved by pure modified starch with 20% (w/v) in the mixture of wall material and active material under 140.5 °C to achieve 400.09 mg/100 g total phenolics, 65.29% product yield, 98.32% solubility, and 25.84% Carr index. The temperature was found significant for only Carr index, while the mixture components were effective for the remaining responses at p < 0.05. Characterization studies under particle size, particle morphology, and glass transition temperature measurements were applied to the microparticles obtained under optimum conditions. Release of bioactive content from the microparticles was evaluated depending on in vitro digestion system. The release was higher in the intestinal system than in the gastric system. Last but not the least, sunflower oil was selected as the model food product for the application of microcapsules as additive. The oxidative stability of the oil was increased by almost 16%, while total phenolic content and antioxidant activity of the oil were enhanced by approximately twice and four times, respectively. [ABSTRACT FROM AUTHOR]

Metal complexes have recently attracted a lot of attention, particularly as anticancer and antibacterial agents, owing to their versatile mechanisms and easily tunable characteristics. However, the application of such compounds in a medical context, especially in cancer treatment, has been hampered due to their limited solubility and stability in water and aqueous solutions, as well as a lack of selectivity. To address these limitations, several approaches have been developed to improve the targeted delivery of these compounds and their solubility. The first strategy involves the physical encapsulation of these metal complexes within carriers to facilitate controlled drug release. The second strategy involves covalently linking metal complexes to polymers, creating prodrugs that can be converted to active drugs at a more controllable rate. Despite the increasing variety of polymers available, the need to develop those able to be metabolized by the body, producing non‐toxic residues, remains crucial for effective treatment, particularly in the area of diseases such as cancer. In this perspective article, an overview of recent developments in the encapsulation of metal complexes using biodegradable polymers for cancer therapy is provided. It is specifically highlighting how the formed nanoparticles (NPs) enhance the selectivity and toxicity toward cancer cells compared to the parent metal complex, while simultaneously reducing the harmful side effects of traditional chemotherapies, opening the door for using them in combination therapies (PDT, PTT). [ABSTRACT FROM AUTHOR]

This article addresses manufacturing structures made via injection molding from biodegradable materials. The mentioned structures can be successfully used as energy-absorbing liners of all kinds of sports helmets, replacing the previously used expanded polystyrene. This paper is focused on injection technological tests and tensile tests (in quasi-static and dynamic conditions) of several composites based on a PLA matrix with the addition of other biodegradable softening agents, such as PBAT and TPS (the blends were prepared via melt blending using a screw extruder with mass compositions of 50:50, 30:70, and 15:85). Tensile tests showed a positive strain rate sensitivity of the mixtures and a dependence of the increase in the ratio of the dynamic to static yield stress on the increase in the share of the plastic component in the mixture. Technological tests showed that increasing the amount of the plasticizing additive by 35% (from 50% to 85%) results in a decrease in the minimal thickness of the thin-walled element that can be successfully injection molded by about 32% in the case of PLA/PBAT blends (from 0.22 mm to 0.15 mm) and by about 26% in the case of PLA/TPS blends (from 0.23 mm to 0.17 mm). Next, the thin-walled elements (dimensions of 55 × 55 × 20 mm) were manufactured and evaluated using a spring-loaded drop hammer. The 60 J impact energy was tested in accordance with the EN 1078 standard. The dynamic crushing test included checking the influence of the materials' temperature (−20, 0, 20, and 40 °C) and the impact velocity. It was proven that the maximum deflection increases with increasing material temperature and an increase in the share of the plastic component in the mixture. The PLA15PBAT85 blend was selected as the most effective material in terms of its use as an energy-absorbing liner for sport helmets. Johnson–Cook and Cowper–Symonds material plasticizing models were constructed. Their use during dynamic FE simulation provided results that were in good agreement with those of the conducted experiment. [ABSTRACT FROM AUTHOR]

As an important biodegradable and partially biobased copolyester, poly(butylene succinate-co-terephthalate) (PBST) possesses comparable thermal and mechanical properties and superior gas barrier performance when compared with poly(butylene adipate-co-terephthalate) (PBAT), but it was found to display poorer melt processability during pelletizing and injection molding. To make clear its melt crystallization behavior under rapid cooling, PBST48 and PBST44 were synthesized, and their melt crystallization was investigated comparatively with PBAT48. PBST48 showed a PBAT48-comparable melt crystallization performance at a cooling rate of 10 °C/min or at isothermal conditions, but it showed a melt crystallization ability at a cooling rate of 40 °C/min which was clearly poorer. PBST44, which has the same mass composition as PBAT48, completely lost its melt crystallization ability under the rapid cooling. The weaker chain mobility of PBST, resulting from its shorter succinate moiety, is responsible for its inferior melt crystallization ability and processability. In comparison with PBAT48, PBST48 displayed higher tensile modulus, and both PBST48 and PBST44 showed higher light transmittance. The findings in this study deepen the understanding of PBST's properties and will be of guiding significance for improving PBST's processability and application development. [ABSTRACT FROM AUTHOR]

The study investigates the hydrolytic degradation behaviors of blends comprising polylactides (PLA) and poly(propylene carbonate) (PPC) in the form of monolayers and bulk films. PLA is a biodegradable polymer widely used in various applications, while PPC offers unique properties, making it a promising candidate for blend formulations. The research explores the degradation kinetics and mechanical properties under controlled hydrolysis conditions. The finding focuses on the compatibility of PLA and PPC, their degradation mechanisms, and the impact of blend composition on degradation rates. Understanding the hydrolytic behavior of these blends is crucial for designing eco-friendly materials with tailored degradation profiles for diverse applications. [ABSTRACT FROM AUTHOR]

3D printing technology has a wide range of applications in many industries, including automotive, aerospace, biomedical, electronics and packaging, requiring different types of filaments to be used in producing 3D printed objects. The most commonly used materials are metals, ceramics, composites and plastics of which the latter are most available. Since it is necessary to reduce pollution caused by waste from conventional petroleum-based plastics, biodegradable polymers made from renewable resources or produced synthetically have gained in importance recently. Polylactic acid, poly(butylene succinate), thermoplastic starch, poly(butylene adipate co-terephthalate) and polycaprolactone are well-known representatives of this group of materials. They possess desirable properties for 3D printing which make them promising materials in many areas of applications. [ABSTRACT FROM AUTHOR]

Polyhydroxyalkanoates (PHAs) are promising biodegradable polymers known for their biodegradability and eco-friendly properties. Recent studies indicate that PHAs can reduce the environmental impact by up to 50% compared to petroleum-based plastics. This comprehensive review evaluates the application of PHAs in sustainable food packaging, covering over 100 studies published between 2018 and 2023. The review highlights advancements in PHA production, with a focus on submerged and solid-state fermentation methods, achieving up to a 60% improvement in production efficiency through optimized culture selection. Sustainable extraction and purification methods have been identified, reducing energy consumption by 30%. Blending PHAs with other biodegradable polymers like polylactic acid, starch, and cellulose enhances material performance, with up to a 40% improvement in mechanical properties. The incorporation of antimicrobial agents and essential oils has been shown to extend the shelf life by 25% while maintaining food safety standards. This review underscores the potential of active PHA-based packaging in improving the barrier properties by 35% when combined with coatings, positioning PHA as a key material for the future of environmentally responsible and safe food packaging. [ABSTRACT FROM AUTHOR]

With the advancement of society, the issue of oil pollution is escalating, therefore we propose a straightforward and efficient approach for fabricating fully biodegradable poly (lactic acid) (PLA)/poly (butylene adipate-co-terephthalate) (PBAT) foams with exceptional selective oil-absorption capabilities through the integration of melt blending and supercritical CO2 (scCO2) foaming techniques. The PLA90 foams, activated at 11 MPa and temperatures ranging from 105 ℃ to 110 ℃, exhibit an expansion ratio of 44 and a highly interconnected open-cell structure with an open-cell content exceeding 80%, effectively mitigating cell shrinkage occurrences. The 105 ℃-triggered PLA90 foam displays pronounced lipophilicity/hydrophobicity, accelerated oil-absorption kinetics, and elevated oil-absorption capacity. Specifically, the equilibrium absorption capacities for cyclohexane and silicone are 12.8 g/g and 20.1 g/g, respectively. Moreover, the maximum absorption capacity decline rate for silicone oil stands at a mere 13.4% over 10 absorption–desorption cycles. The findings presented in this study establish a theoretical framework and offer empirical evidence to support the development of fully biodegradable, high-performance, and reusable oil-absorption materials. [ABSTRACT FROM AUTHOR]

The paper highlights the benefits of using seed tape planting technology, which include reduced seeding rate, optimized application of fertilizers and chemicals, and the ability to quickly switch between different crops or seed varieties. This technology shows positive effects on nearly all agricultural crops. (Research purpose) The study aims to explore the history of the emergence and application of seed tapes (seed ropes) for planting, detailing their design features and production technologies. (Materials and methods) The research employs a historical-analytical method, examining scientific publications, patent databases, such as Espacenet and the Federal Institute of Industrial Property, as well as photographic materials. (Results and discussion) The paper provides information on the origin of the first seed carriers which were flexible holding strips of paper or similar material that enclosed seeds. It covers the development and advancement of this planting technology, highlighting the use of currently most popular seed tapes. Universal or combined tapes and twisted seed strands can serve as carriers of fertilizers, pesticides, herbicides, and other substances in various combinations, in addition to seeds themselves. The paper reviews inventions related to the types and manufacturing methods of seed tapes and seed ropes proposed in different countries from 1898 to 2023. (Conclusions) The differences between seed tapes and seed ropes primarily lie in the mechanization of their production. The seed carrier can be made from various biodegradable materials, such as paper, plant fiber cloth, polymers or others. When manufacturing these tapes, it is necessary to minimize seed damage. The present research results in the formulation of principles for selecting biodegradable polymeric materials for seed tape planting technology. These principles include high diffusion rates, swelling properties, and maintaining a balance between tape biodegradation and biochemical reactions in plant cells.

3D printing technology has a wide range of applications in many industries, including automotive, aerospace, biomedical, electronics and packaging, requiring different types of filaments to be used in producing 3D printed objects. The most commonly used materials are metals, ceramics, composites and plastics of which the latter are most available. Since it is necessary to reduce pollution caused by waste from conventional petroleum-based plastics, biodegradable polymers made from renewable resources or produced synthetically have gained in importance recently. Polylactic acid, poly(butylene succinate), thermoplastic starch, poly(butylene adipate co-terephthalate) and polycaprolactone are well-known representatives of this group of materials. They possess desirable properties for 3D printing which make them promising materials in many areas of applications.

Biodegradable biopolymers like polyhydroxybutyrate (PHB) hold promise for sustainable packaging, but their inherent degradability reduces material stability. Synthetic stabilizers, though effective, raise environmental and potential toxicity concerns. This study explores a multifunctional natural anti-aging agent: a hemp extract rich in cannabidiol (CBD) and cannabichromene (CBC). PHB composites with varying hemp extract concentrations were prepared and subjected to thermooxidative and weathering aging. Characterization employed FTIR-ATR, carbonyl index, and spectrophotometry. Static mechanical properties, DSC, and surface free energy (SFE) were also assessed. Notably, the hemp extract exhibited stability under ambient conditions but showed migration with time and aging. The results suggest a plasticizing effect on PHB and highlight the contrasting roles of the extract: inhibiting thermooxidative aging while potentially accelerating aging under atmospheric conditions. This opens avenues for tailoring material durability, further evaluated by life cycle analysis (LCA). This work represents one of the first investigations into hemp extract as an anti-aging agent for eco-friendly polymers, expanding the knowledge base of natural multifunctional additives. [ABSTRACT FROM AUTHOR]

The growing interest in biodegradable scaffolds for bone regeneration created a need to investigate new materials suitable for scaffold formation. Poly(lactic acid) (PLA) is a polymer commonly used in biomedical engineering, e.g. in tissue engineering as a biodegradable material. However, the mechanical behavior of PLA along its degradation time is still not explored well. For this reason, the mechanical properties of PLA scaffolds affected by incubation in physiological medium needs to be investigated to show the potential of PLA to be used as a material for biodegradable scaffold formation. The purpose of this research is to determine the mechanical properties of PLA scaffolds before and after incubation, and to apply constitutive material models for further behavior prediction. Two sets of PLA scaffolds were printed by the 3D printer "Prusa i3 MK3S" and sterilized by ultraviolet light and ethanol solution. The first set of specimens was incubated in DMEM (Dulbecco's Modified Eagle Medium) for 60, 120, and 180 days maintaining 36.5 °C temperature. The mechanical properties of the scaffolds were determined after performing the compression test in the "Mecmesin MultiTest 2.5-i" testing stand with a force applied at two different speed modes. The obtained data was curve fitted with the hyperelastic material models for a model suitability study. The second set of specimens was incubated in PBS (Phosphate Buffered Saline) for 20 weeks and used in a polymer degradation study. The obtained results show that the mechanical properties of PLA scaffolds do not decrease during incubation in physiological medium for a predicted new bone tissue formation period, though hydrolysis starts at the very beginning and increases with time. PLA as a material seems to be suitable for the use in bone tissue engineering as it allows to form biocompatible and biodegradable scaffolds with high mechanical strength, required for effective tissue formation. [ABSTRACT FROM AUTHOR]

In this work, polylactide (PLA) was loaded with wood flour (WF) or hazelnut shells (HSs) (10% and 20% of fillers). The matrix and biocomposites were fully characterized from a mechanical and rheological point of view to test their processability and mechanical performance. Compost burial degradation test (30 days), with or without a prior photo‐oxidation step, assessed their biodegradability after an outdoor application, and was monitored by weight loss (WL). The viscosity of the biocomposites was lower than that of the matrix and this unusual result can be attributed to a limited adhesion between the PLA and fillers. Both fillers increased the elastic modulus but decreased the tensile strength and elongation at break. As for the weathering, the degradation of PLA was mostly due to hydrolytic chain scission due to the presence of humidity. Resistance of PLA to UV irradiation improved in presence of both the two fillers. Their lignocellulosic nature was responsible for this behavior. Both fillers induced a high resistance and lower degradation in compost: WL percentages of virgin PLA was about 26%, biocomposites with 20% of WF or HS showed WL of about 10% and 14%, respectively. Photo‐oxidation (36 h with condensation cycle) increased the compost degradation rate of both biocomposites and WL of PLA with 20% of WF or HS were about 15% and 21%, respectively, after 30 days. Highlights: Poor adhesion between the matrix and fillers reduced the biocomposites viscosity.Fillers increased the elastic modulus but decreased the properties at break.Both fillers improved the resistance of PLA to UV irradiation.Biocomposites showed a lower susceptibility to compost degradation than PLA.Photo‐oxidation increased the compost degradation rate of biocomposites. [ABSTRACT FROM AUTHOR]

The escalating environmental crisis posed by single-use plastics underscores the urgent need for sustainable alternatives. This study provides an approach to introduce biodegradable polymer blends by blending synthetic polyvinyl alcohol (PVA) with natural polymers—corn starch (CS) and hydroxypropyl methylcellulose (HPMC)—to address this challenge. Through a comprehensive analysis, including of the structure, mechanical strength, water solubility, biodegradability, and thermal properties, we investigated the enhanced performance of PVA-CS and PVA-HPMC blends over conventional polymers. Scanning electron microscopy (SEM) findings of pure PVA and its blends were studied, and we found a complete homogeneity between the PVA and both types of natural polymers in the case of a high concentration of PVA, whereas at lower concentration of PVA, some granules of CS and HMPC appear in the SEM. Blending corn starch (CS) with PVA significantly boosts its biodegradability in soil environments, since adding starch of 50 w/w duplicates the rate of PVA biodegradation. Incorporating hydroxypropyl methylcellulose (HPMC) with PVA not only improves water solubility but also enhances biodegradation rates, as the addition of HPMC increases the biodegradation of pure PVA from 10 to 100% and raises the water solubility from 80 to 100%, highlighting the significant acceleration of the biodegradation process and water solubility caused by HPMC addition, making these blends suitable for a wide range of applications, from packaging and agricultural films to biomedical engineering. The thermal properties of pure PVA and its blends with natural were studied using diffraction scanning calorimetry (DSC). It is found that the glass transition temperature (Tg) increases after adding natural polymers to PVA, referring to an improvement in the molecular weight and intermolecular interactions between blend molecules. Moreover, the amorphous structure of natural polymers makes the melting temperature ™ lessen after adding natural polymer, so the blends require lower temperature to remelt and be recycled again. For the mechanical properties, both types of natural polymer decrease the tensile strength and elongation at break, which overall weakens the mechanical properties of PVA. Our findings offer a promising pathway for the development of environmentally friendly polymers that do not compromise on performance, marking a significant step forward in polymer science's contribution to sustainability. This work presents detailed experimental and theoretical insights into novel polymerization methods and the utilization of biological strategies for advanced material design. [ABSTRACT FROM AUTHOR]

Coronary artery disease (CAD) is one of the leading death-causing diseases. Various drug treatments and surgical procedures are available to treat CAD. Stenting is one of the minimally invasive surgical procedures through which CAD is treated. There are different types of stents developed over the years, such as bare metal stents, drug-eluting stents, and recently, bioresorbable vascular stents (BVS). Previously, the metal-BVS were prepared by conventional techniques like micro-injection molding, braiding technique, laser cutting, micro-photochemical etching or micro-electro discharge machine and micro-precision milling. These methods were having problems like oxidation, especially in the case of bioresorbable stents using polymers. To overcome these limitations, additive manufacturing techniques like 3D printing technology were developed to fabricate BVS. 3D printing is the layer-by-layer addition of material to fabricate products using computer software. There are various types of 3D printers; fused deposition modeling and sintered laser melting are the most widely used printers for developing 3D-printed BVS. In this review article, we have comprehensively taken an overview of BVS manufactured by different 3D printing techniques using several biodegradable polymers. These studies showed some encouraging results with mechanical properties and biocompatibility testing in vitro and in vivo. Therefore, 3D-printed BVS can be further explored as a fast-growing alternative in personalized therapy in vascular care. [ABSTRACT FROM AUTHOR]

Poly(lactic acid) (PLA) and poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) exhibit valuable mechanical properties like high stiffness and tensile strength but are sensitive to processing parameters. The influence of these parameters was evaluated by measuring the variation of melt viscosity during processing. For all experiments, in the absence of chain extenders, the decrease in melt viscosity clearly showed the degradation of polymers during processing. This is more pronounced for PHBV than PLA. In order to compensate for the degradation and, if possible, improve the melt strength of these bio-based polymers, two chain extenders have been evaluated: dicumyl peroxide (DCP) and a polymeric epoxy acrylate chain extender (Joncryl® ADR 4400). DCP reacts quickly with PLA and PHBV, while the epoxy-acrylate chain extender shows slower kinetics. For the PLA, with both investigated chain extenders, an increase in the molecular weight as compared with the virgin polymer and eventually the apparition of an insoluble fraction due to branching and crosslinking are observed. In the case of PHBV, the degradation is compensated by using DCP, requiring short processing times. No significant increase in molecular weight was observed when using the polymeric epoxy acrylate chain extender, requiring longer residence times, although the apparition of a gel fraction suggests the presence of branching and crosslinking. [ABSTRACT FROM AUTHOR]

Poly(lactic acid) (PLA) is a bio-based linear aliphatic polyester that is broadly used in biomedical applications. A shortcoming of PLA is its brittleness and low toughness. Poly(hydroxybutyrate) (PHB) is a microbial bioprocessed and biodegradable polyester. To enhance toughness of PLA, it was melt-blended with PHB-based thermoplastic elastomer in various proportions by using a twin-screw extruder. Scanning electron microscope images reveal that PLA forms a continuous phase in PLA/PHB blends reinforced with inclusions of PHB. Fourier transform infrared spectroscopy measurements demonstrate strong intermolecular interactions between PLA and PHB chains. Differential scanning calorimeter thermogramms show that PHB reduces the glass transition temperature of PLA and affects its crystalline structure. When the mass fraction of PHB was 20, the glass transition temperature of the blend decreased to 33.9°C. Rheological measurements demonstrate that blending of PLA with PHB changes qualitatively the dependence of its viscosity on shear rate. Quasi-static (uniaxial tension) and dynamic (impact) tests confirm that blending of PLA with PHB results in a noticeable (by a factor of three) increase in its impact toughness and causes transition from the brittle to ductile regime of fracture. When the mass fraction of PHB was 40, the impact toughness reached to 0.40 kJ/m2, almost 3 times to neat PLA. [ABSTRACT FROM AUTHOR]

The use of macroalgae for food has been extensive in Asia historically. However, there has been a renewed interest at present in macroalgae due to its recognition as a potential carbon capture agent and a blue carbon donor besides their utility in biofuel production. Bioplastics is an umbrella term for a wide variety of polymers that can be either biobased or biodegradable, or both. Macroalgal polysaccharides and their inherent film‐forming capacity are exploited in the bioplastics industry and macroalgal polysaccharide‐based biofilms are extensively used in food packaging due to their compatibility and ease of production. Commercial macroalgae‐based bioplastics production is ongoing, with research dedicated to the development of biodegradable/compostable biofilms suitable for the food packing and biomedicine sector. This review aims to provide an overview of the polysaccharides of macroalgae that can be used to form biofilms and bioplastics. Different methods for biofilm formation are discussed along with summarizing the effect of plasticizers, the method of film formation, and biodegradability. The major source of marine macroalgal polysaccharaides are agar, alginate, carrageenan, laminarin, fucoidan, and ulvan. Different groups of macroalgae are utilized for the production of polysaccharide derived bioplatics, namely, brown algae (Padina pavonica, Ascophyllum nodosum, Laminaria japonica, Rugulopteryx okamurae, Sargassum natans, Sargassum siliquosum, Jolyna laminarioides, Gracilaria salicornia), green algae (Ulva fasciata, Halimeda opuntia, Codium fragile, Ulva intestinalis, Ulva lactuca, Ulva rigida), and red algae (Eucheuma cottonii, Porphyra sp., Kappaphycus alvarezii, Gracilaria corticata). The outcome of the review reveals that there is a vast scope for macroalgal polysaccharide‐derived bioplastics for a sustainable environment. [ABSTRACT FROM AUTHOR]

Melt blending is a reliable and well‐demonstrated strategy for improving the mechanical, thermal, rheological, and surface properties of biopolymers. Poly(hydroxy‐3‐butyrate‐co‐3‐hydroxyvalerate) (PHBV) and poly(butylene adipate‐co‐terephthalate) (PBAT) are the two popular choices for blending polymers due to their diverse properties and complementary soil biodegradable behaviour. Due to their immiscibility, however, blending with the help of processing additives is necessary to reap the most significant benefits from this process and to avoid immiscibility issues. This study utilized the additives (peroxides and epoxy‐based chain extender) to compatibilize the biodegradable polymers PHBV and PBAT in a 60:40 blending ratio. The tensile strength and Young's modulus of the PHBV/PBAT(60/40) blend were improved by 32% and 64%, respectively, after adding a combination of peroxide (0.02 phr) and chain extender (0.3 phr) due to the formation of a complex network structure with increased chain length. The positive effect of an additive addition was also reflected by a 30°C increment in heat deflection temperature of biodegradable blend due to its high modulus value as supported by mechanical properties. The combined action of a peroxide and chain extender demonstrated a significantly higher complex viscosity of the PHBV/PBAT(60/40) blend due to the formation of a crosslinked polymer network as analyzed by rheological analysis. Our research demonstrated the effect of additives and their combined impact on analytical properties of PHBV/PBAT(60/40) blend to guide future work in improving their candidature to serve as a drop‐in solution in replacing non‐biodegradable petro‐based plastic products. [ABSTRACT FROM AUTHOR]

A sodium bentonite product (nanoclay) was added to a polyhydroxybutyrate/ethyl cellulose (PHB/EC) blend coating agent, and the impact of the nanoclay content on the properties of the coated paper was investigated. The organically treated nanoclay exhibited enhanced compatibility with the PHB/EC blend, ensuring uniform dispersion within the coating layer and improving the barrier properties of the coated paper. The mechanical properties of the PHB/EC blend-coated paper with nanoclay demonstrated ductile behavior, reducing the tensile strength and increasing the elongation. However, at higher nanoclay loadings, specifically up to 25%, aggregation among nanoclay particles occurred. This hindered the enhancement of barrier properties, thereby decreasing the degree of elongation. Incorporating nanoclay as a filler in the PHB/EC blend at suitable levels showed potential for further enhancing the barrier properties and ensuring economic feasibility in the production of packaging paper. [ABSTRACT FROM AUTHOR]

Bio-based and biodegradable materials play a vital role in a sustainable and green economy. These materials must exhibit properties that are similar to or better than the properties of oil- or coal-based materials and require sophisticated synthesis technologies and detailed knowledge of structure–property correlations. For comprehensive molecular structure elucidation, advanced analytical methods, including coupled and hyphenated techniques that combine advanced fractionation and information-rich spectroscopic detectors, are an indispensable tool. One important tool for fractionating complex polymers regarding molecular size is size exclusion chromatography. For fractionating polymers with regard to chemical composition, solvent (or temperature) gradient HPLC has been developed. The combination of different liquid chromatography methods in comprehensive two-dimensional HPLC setups is another important tool. Today, a toolbox of HPLC methods is in place that enables the fractionation of complex bio-based and biodegradable polymers according to the most important molecular parameters including molecular size, composition, functionality, and branching. Here, an overview of the different techniques and some major applications is presented. Some representative developments in the field are discussed, and different techniques, experimental protocols, and applications are highlighted. [ABSTRACT FROM AUTHOR]

The objective of this work was to evaluate anaerobic digestion processes of mixtures of cassava starch‐based polymer (CSP) and papaya fruit pulp waste (PPW) at different ratios, with physical division of digestion stages. Acidogenic phase (phase 1) was conducted under temperature of 45°C and hydraulic retention time of 96 h. Monitoring reactors with destructive samples were subjected to the same conditions in order to assess the initial degradation profile of the substrates. The methanogenic phase (phase 2) was conducted under temperature of 37°C and the hydraulic retention time was defined as equal to the time the biogas production ceased. The results showed that the CSP/PPW mixtures presented interesting synergism and high biogas production potential under the conditions studied. The treatment with CSP/PPW at the ratio of 75/25 showed the best digestion performances in the phase 1. The highest CSP to PPW ratios showed satisfactory results for accumulated biogas productions (5955.58 mL) and for maximum biogas production rate (25.64 mL gVS−1 day−1) in the phase 2. [ABSTRACT FROM AUTHOR]

Biobased and biodegradable plastics have emerged as promising alternatives to conventional plastics offering the potential to reduce environmental impacts while promoting sustainability. This study focuses on the production of multilayer blown films with enhanced functional properties suitable for food packaging applications. Films were developed through co-extrusion in a three-layer film configuration, with Polybutylene Succinate (PBS) and Polybutylene Succinate Adipate (PBSA) as the external and internal layers, respectively. The functional layer consisted of Polyhydroxybutyrate (PHB) enhanced with nanoclays Cloisite® 30B at varying weight ratios. Films were also processed by manipulating the extruder screw speed of the functional layer to investigate its impact on the functional properties. Rheology, mechanical strength, and barrier performance were characterised to establish correlations between processing conditions and functional layer blends (Cloisite® 30B/PHB) on the properties of the resultant films. Rheological test results indicated that the system with 5% Cloisite® had the best polymer/nanofiller matrix dispersion. Mechanical and permeability tests showed that by varying the process conditions (the alteration of the thickness of the functionalized layer) resulted in an improvement in mechanical and barrier properties. Furthermore, the addition of the nanofiller resulted in a stiffening of the film with a subsequent decrease in permeability to oxygen and water vapour. [ABSTRACT FROM AUTHOR]

Achilles tendon defect is caused by direct or indirect violence that makes it difficult for the tensile strength of the Achilles tendon to resist external forces. It is characterized by a lack of tissue integrity around the Achilles tendon, local bruising or bacterial infection, and ultimately leads to abnormal gait. This paper reviews the recent research progress of biodegradable polymeric materials in treating Achilles tendon defects at home and abroad, mainly introducing the therapeutic impact on the repair of Achilles tendon defects from materials alone, materials combined with drugs or cells. [ABSTRACT FROM AUTHOR]

In recent years, researchers have increasingly directed their focus toward the biomedical field, driven by the goal of engineering polymer systems that possess a unique combination of both electrical conductivity and biodegradability. This convergence of properties holds significant promise, as it addresses a fundamental requirement for biomedical applications: compatibility with biological environments. These polymer systems are viewed as auspicious biomaterials, precisely because they meet this critical criterion. Beyond their biodegradability, these materials offer a range of advantageous characteristics. Their exceptional processability enables facile fabrication into various forms, and their chemical stability ensures reliability in diverse physiological conditions. Moreover, their low production costs make them economically viable options for large-scale applications. Notably, their intrinsic electrical conductivity further distinguishes them, opening up possibilities for applications that demand such functionality. As the focus of this review, a survey into the use of biodegradable conducting polymers in tissue engineering, biomedical implants, and antibacterial applications is conducted. [ABSTRACT FROM AUTHOR]

Dermatology and cosmetology currently prioritize healthy, youthful-looking skin. As a result, research is being conducted worldwide to uncover natural substances and carriers that allow for controlled release, which could aid in the battle against a variety of skin illnesses and slow the aging process. This study examined the biological and physicochemical features of novel hydrogels containing cannabidiol (CBD) and α-terpineol (TER). The hydrogels were obtained from ε-caprolactone (CL) and poly(ethylene glycol) (PEG) copolymers, diethylene glycol (DEG), poly(tetrahydrofuran) (PTHF), 1,6-diisocyanatohexane (HDI), and chitosan (CHT) components, whereas the biodegradable oligomers were synthesized using the enzyme ring-opening polymerization (e-ROP) method. The in vitro release rate of the active compounds from the hydrogels was characterized by mainly first-order kinetics, without a "burst release". The antimicrobial, anti-inflammatory, cytotoxic, antioxidant, and anti-aging qualities of the designed drug delivery systems (DDSs) were evaluated. The findings indicate that the hydrogel carriers that were developed have the ability to scavenge free radicals and impact the activity of antioxidant enzymes while avoiding any negative effects on keratinocytes and fibroblasts. Furthermore, they have anti-inflammatory qualities by impeding protein denaturation as well as the activity of proteinase and lipoxygenase. Additionally, their ability to reduce the multiplication of pathogenic bacteria and inhibit the activity of collagenase and elastase has been demonstrated. Thus, the developed hydrogel carriers may be effective systems for the controlled delivery of CBD, which may become a valuable tool for cosmetologists and dermatologists. [ABSTRACT FROM AUTHOR]

Repaglinide (RPG) has a high rate of absorption from the gastrointestinal system after oral administration due to low log P value. Hence, in this study the inotropic gelation process was used to fabricate mucoadhesive microspheres of RPG using biodegradable polymers such as guar gum, chitosan, and fenugreek seed mucilage. The mucoadhesive microspheres were characterized and tested in vitro followed with oral glucose tolerance test on animals. Scanning electron microscopy images demonstrated that the fabricated microspheres were smooth and spherical with lack of pores. The particle size and polydispersity index (PDI) of microsphere was observed as 300 μm and 0.349, respectively with high positive zeta potential of 38.4 mV. The results of percentage yield and swelling index analysis demonstrated 87.04 % and 90.65 %, respectively for optimized formulation with an in vitro release capability of 95.20 % in 10 h. In addition, the results suggested that the mucoadhesive microspheres successfully entrapped 94.86 ± 4.25 % of the RPG. These results clearly indicated that the optimized formulation of RPG fortified mucoadhesive microspheres reduced the blood glucose level (hyperglycemia due to glucose load 2 g/kg) significantly, compared to marketed RPG formulation (0.25 mg/kg) after 2 h of oral administration. Additionally, RPG incorporated microspheres enable the regulated blood glucose level over a 10 h. Hence, the formulation demonstrated overall improvement in anti-diabetic efficacy. [ABSTRACT FROM AUTHOR]

Understanding the degradation behavior of polymer composites is crucial for their practical application, especially in areas such as biomedicine and environmental engineering. In this study, we investigated the influence of titanium dioxide (TiO2) particle size and content, containing 0.5, 1, 2, 5, and 10 wt% m/nTiO2, on the degradation mechanism of biodegradable polycaprolactone (PCL) biocomposites. The degradation kinetics of the prepared biocomposites were evaluated using the Friedman method in conjunction with multivariate nonlinear regression facilitated by the Netzsch Thermokinetics software. The results indicate different degradation mechanisms for PCL biocomposites containing TiO2 microparticles compared to biocomposites containing TiO2 nanoparticles. However, the PCL biocomposites with TiO2 microparticles showed a three-step degradation process, and the PCL biocomposites with TiO2 nanoparticles exhibited a four-step degradation process. This difference can be attributed to the observed agglomeration of TiO2 nanoparticles within the PCL matrix, which leads to an additional diffusion step in the degradation process. Interestingly, the addition of TiO2 particles did not change the basic degradation mechanism of PCL but prolonged the degradation process to a higher conversion range. These findings shed light on the complicated interplay between the properties of the filler particles and the behavior of the polymer matrix and provide valuable clues for the design and optimization of biodegradable biocomposites. [ABSTRACT FROM AUTHOR]

A novel bio-based and compostable cellulose film (NF) was studied for the packaging of fresh baby spinach, with results compared to a petroleum-derived non-biodegradable polypropylene (PP) film, currently used to market the same product. Baby spinach is a leafy vegetable with high metabolic activity. A preliminary analysis of the product respiration rate was conducted to select the cellulose film grade. The chosen NF film ensures the optimal O2 and CO2 concentration in the headspace, performing even better than the conventional PP film. In fact, when the leafy vegetable is packed within PP, after 15 days of storage, no equilibrium value of gas concentration was reached, which, upon longer storage, might cause anaerobic conditions and off-odor development. Baby spinach leaves packed with NF film showed a slower decrement in texture properties and total antioxidant capacity during storage with respect to control samples, but also a larger weight loss, mostly due to the high-water permeability of the cellulose. However, water condensation upon storage was noted for both packaging materials. Analysis of mechanical, thermal, and barrier properties of the NF film before, during, and after use probed no deterioration of material properties, confirming the potentiality of this polymer for sustainable packaging of fresh leafy vegetables. [ABSTRACT FROM AUTHOR]

The utilization of advanced polymeric materials has indeed emerged as a significant trend in sustainable agriculture, offering a range of innovative applications aimed at enhancing productivity, minimizing environmental impact, and promoting resource efficiency. Smart polymeric materials enable the controlled release of pesticides, herbicides, and fertilizers, thereby enhancing their efficacy while reducing the quantities needed. Superabsorbent polymeric materials act as soil conditioners, assisting in alleviating the negative impacts of drought by retaining moisture and enhancing soil structure. This fosters improved plant growth and resilience in water-scarce environments. Polycationic polymers play a role in plant bioengineering, facilitating genetic transformation processes aimed at enhancing crop productivity and disease resistance. Advanced polymeric systems contribute to the arsenal of precision agriculture tools by enabling precise delivery and targeted application of agricultural inputs. This approach enhances resource efficiency, reduces waste, and minimizes environmental impact while optimizing crop yields. In reviewing recent developments in the design and application of advanced polymeric systems for precision agriculture, several key considerations emerge.

Understanding the release behaviour of nanodrugs is a crucial step to better assess and control therapeutic outcomes and unfavourable side effects. Herein, we report a systematic study comparing the release kinetics and thermodynamics of paclitaxel (PTX) from supramolecularly assembled sub-micron particles based on natural macromolecules such as zein, whey, casein, bovine serum albumin (BSA) and conventional stabilizers such as pluronic F-127 (poloxamer 407), and β-cyclodextrin (β-CD) to gain insights into the role of carrier chemistry. For this purpose, nanomedicines with statistically indifferent sizes —in the range of 191.0 ± 0.8 nm (BSA) to 243.3 ± 11.6 nm (zein) were prepared (p > 0.05). The zeta potential values ranged from −3.2 ± 1.1 mV (pluronic F-127) to −17.2 ± 1.8 mV (whey) in phosphate buffered saline. The type of nanocarrier significantly influenced the long-term steady-state plateau of the release, resulting in a cumulative release of 70.3 ± 2.0 % of PTX from casein (the highest) and 46.8 ± 4.7 % of PTX from zein (the lowest). Time-resolved release data were analysed with various kinetical models, encompassing zero-order, first-order, Higuchi, Peppas-Sahlin, and Korsmeyer-Peppas kinetics. The analysis revealed that the Korsmeyer-Peppas model best captured the data. For these nanomedicines, the half-life of the encapsulated drugs was found to be 106.4 ± 31.3 h (zein), 4.7 ± 1.2 h (whey), 10.7 ± 1.8 h (pluronic F-127), 6.4 ± 0.9 h (casein), 10.8 ± 3.2 h (β-CD), and 4.0 ± 1.0 h (BSA). TEM characterization revealed differences in the macromolecular arrangement of the active ingredient within these nanocarriers, in addition to the structural differences among the various encapsulating agents. These differences manifested as variations in the internal nanostructures, leading to the creation of distinct microenvironments that could either facilitate or impede the movement of PTX molecules through the encapsulant matrices. In clinical settings, such fine details of nanocarrier design are important: by choosing the most appropriate nanocarrier (or their mixtures), clinicians can fine-tune drug administration to obtain the intended therapeutic window while mitigating the risk of potential negative reactions.

This study aimed to produce PHB using hydrogenic effluent discharged from the biohydrogen production process with freshwater microalgae including Coelastrella sp. KKU-P1, and Acutodesmus sp. KKU-P2. Batch experiments explored the influence of initial pH and hydrogenic effluent concentration, revealing optimal conditions at 10 % (v/v) effluent concentration and a pH of 6.5 for both KKU-P1 and KKU-P2. Subsequently, medium formulation and photoperiods were optimized to maximize biomass and PHB accumulation. The results showed that the optimal condition for PHB accumulation with KKU-P1 and KKU-P2 was nitrogen phosphorus (NP)-limited Bold's Basal Medium (BBM) under dark conditions. A two-step PHB accumulation in the upscale bioreactor was investigated under optimal conditions. The results showed that KKU-P1 achieved maximum PHB, protein, carbohydrate, and lipid contents of 4.57 %, 29.37 %, 24.76 %, and 13.21 %, respectively, whereas KKU-P2 achieved 6.35 %, 31.53 %, 16.16 %, and 4.77 %, respectively. Based on these findings, it appears that a mixotrophic approach under nutrient-limiting conditions is effective for PHB production in both KKU-P1 and KKU-P2 strains.