Biodegradable Polymer Research Articles

Enhancing Conductivity and Viscosity in Melt Electrospinning of Biodegradable Polymers through Additive Modification

Biodegradable polymers, derived from renewable sources, have diverse applications spanning biomedical, packaging, textile fibers, and technical fields. Despite their notable attributes, the high viscosity and low electrical conductivity of these polymers present challenges, particularly in melt electrospinning (MES). Thus, this study endeavors to boost the electrical conductivity and viscosity of molten biodegradable polymers for MES nanofiber production through the incorporation of various additives. These additives were chosen based on prior research identifying promising compounds. Subsequently, this investigation compares the efficacy of different additives in enhancing conductivity and viscosity, aiming to optimize polymer solutions for efficient nanofiber manufacturing. The outcomes of this research are anticipated to advance biodegradable polymer-based nanofiber production methods and foster the creation of high-performance, sustainable materials with broad industrial applications.

Operando Raman and in-Situ UV-Vis Spectroscopy Unveil the Impact of Solvent Donor and Acceptor Numbers on Gel Polymer Electrolytes in Lithium-Sulfur Batteries

Lithium-sulfur (Li-S) batteries boast a specific capacity five times greater than current Li-intercalation systems. Still, practical implementation faces challenges tied to liquid electrolytes, i.e., lithium metal dendrites formation, polysulfide redox-shuttle, and flammability [1]. Thus, we focus on developing biodegradable gel polymer electrolytes to overcome these issues, fostering eco-friendly, safer, and more effective energy storage solutions. Polycaprolactone (PCL) emerges as a promising GPE candidate due to its biodegradable nature and broad stability range (~5V vs Li0/Li+). Our current study investigates the influence of solvent selection, explicitly focusing on donor and acceptor numbers, in formulating gel polymer electrolytes for Lithium-Sulfur batteries. Leveraging operando Raman and in-situ UV-Vis spectroscopy, our research provides real-time insights into the dynamic interactions within the gel during battery operation, shedding light on the evolving electrochemical processes. Moreover, by systematically analyzing the impact of solvent properties on gel characteristics, we reveal a nuanced relationship, emphasizing the importance of tailored solvent selection for optimizing gel performance. Operando Raman spectroscopy enables the observation of bond formations and structural changes in the gel, while in-situ UV-Vis spectroscopy tracks the behavior of polysulfides, facilitating the identification of specific interactions and offering a comprehensive understanding of the gel's role in mitigating polysulfide shuttling. This work aims to advance our fundamental knowledge of gel polymer electrolytes and provide a pathway for optimizing battery performance and mitigating degradation mechanisms. Notably, our study introduces a novel dimension by employing a custom-built UV-Vis setup, enhancing the versatility and applicability of these spectroscopic techniques in probing the intricate interactions within gel polymer electrolytes.Reference1-Pervez, S. A.; Vinayan, B. P.; Cambaz, M. A.; Melinte, G.; Diemant, T.; Braun, T.; Karkera, G.; Behm, R. J.; Fichtner, M., Electrochemical and compositional characterization of solid interphase layers in an interface-modified solid-state Li–sulfur battery. Journal of Materials Chemistry A2020, 8 (32), 16451-16462.

Response surface methodology-based preparation of sago starch bioplastic film for food packaging

The increase in the use of plastics during the past few decades has caused environmental pollution due to the non-biodegradable and recalcitrance nature of the plastics. This has caused great problems for the solid waste management efforts. The development of biodegradable polymers from natural and renewable ingredients can address the challenges caused by plastic pollution. The present work deals with the optimization of the preparation process of sago starch-based biodegradable bioplastic films. The sago starch, glycerol-sorbitol mixture, and chitosan were used as polysaccharides, plasticizers, and antimicrobial agents, respectively. The factors screening and design optimization were performed using response surface methodology and Box-Behnken Design to investigate the interactions between all components in the film preparation. Furthermore, the developed bioplastic films were characterized through field emission scanning electron microscopy and Fourier transform infrared spectroscopy. The antimicrobial susceptibility assay showed the inhibition of the growth of Bacillus pumilus and Alcaligenes faecalis XF1 by incorporation of cinnamon essential oil into the film. Moreover, the developed films successfully reduced the proliferation of fungal growth on packaged bread samples. The microbial analysis found that the shelf life of the wheat bread was improved from 3 to 15 days. The sago starch bioplastic films developed in this study can potentially meet the requirements for food packaging films.

Improving durability and efficiency in passive direct ethanol fuel cells using a biodegradable polyvinyl alcohol/epoxidized natural rubber membrane

AbstractIn this study, a novel biodegradable polymer electrolyte membrane with reduced fuel crossover, high selectivity, and high conductivity compared with Nafion 117 membrane in direct ethanol fuel cells (DEFCs) has been reported. Herein, polyvinyl alcohol/epoxidized natural rubber (PVA/ENR) blend membranes were synthesized via a simple solution casting method and applied in DEFCs. The structural and physicochemical features of the PVA/ENR blend membranes were examined using FESEM, FTIR, XRD, water absorption, ethanol uptake, swelling ratio and oxidative stability. ENR enhances the chemical, structural, and mechanical characteristics of PVA, making it a valuable material in fuel cell applications. The incorporation of ENR into the PVA matrix results in a compact morphology, excessive multifunctional groups, low fuel crossover, and high selectivity. The optimum membrane thickness achieves the highest selectivity, reaching up to 12.32 × 104 S s cm−3 at 30°C. Additionally, the maximum power density achieved is 19.52 mW cm−2, surpassing that of the Nafion membrane, which is only 14.55 mW cm−2 at 90°C. Furthermore, this biodegradable membrane can sustain operation for 1000 h at 90°C, owing to its ability to maintain hydration for an extended period. This study represents the first attempt to combine PVA and ENR in fuel cells.

FDM printing of microneedles based on biocompatible and biodegradable thermoplastic polymers

AbstractMicroneedles are an emerging class of transdermal drug delivery systems for biomedical applications. These devices allow minimally invasive and painless drug delivery, making them an attractive alternative to hypodermic injections. This paper focuses on the study of polymer‐based solid microneedles fabrication process using the fused deposition modeling (FDM) method. Biodegradable and biocompatible polymers are selected as printing materials. For this study, the thermoplastic polylactic acid (PLA), currently used for FDM microneedle preparation was selected. To overcome the potential brittleness of PLA during transdermal application, two other materials are also studied: polycaprolactone (PCL) and a PLA/PCL blend. The effect of 3D printing parameters on the dimensional accuracy of the microneedles is studied to determine the optimum printing conditions for each filament. In addition, the dimensions and/or geometry of the microneedles are modified to print its with minimal dimensions. Then, a post‐fabrication chemical etching treatment is used to improve both, size and shape of the printed solid microneedles.

Development and Characterızatıon of Polylactıc Acıd (Pla)

Today, the usage areas of polymer materials are quite wide. It is not possible to recycle petroleum-based polymers. Synthetic polymers have wide usage areas; This makes synthetic polymers the most important cause of environmental pollution. In particular, disposable products are produced from synthetic polymer materials and then recycled in nature for many years; It has pushed us to seek a solution to this problem. At the same time, decreasing oil resources pose a raw material threat for the production of oil-based products. Therefore, it is aimed to minimize the use of synthetic polymers used in many industries such as automotive, household appliances, food and pharmaceutical packaging, and to contribute to the increase of biopolymer studies. In this study, the production and mechanical characterization of Polylactic Acid, a natural polymer, was performed. PLA, which is a biodegradable polymer as well as a natural polymer, is thought to be an alternative to synthetic polymers in many sectors. Pure natural PLA samples were molded with an injection device and mechanical characterization was performed. The results of tensile and 3-point bending tests were interpreted. As a result of the mechanical tests of PLA, a biocomposite was produced using chestnut shells to improve the mechanical properties and the mechanical properties of this biocomposite were examined. It was concluded that 25% chestnut shell reinforcement improved the mechanical properties of PLA.

Exploring the potential of insect gut symbionts for polyethylene biodegradation

The global issue of synthetic plastic pollution is escalating, necessitating innovative bioremediation approaches. Specific insect species have developed symbiotic associations with intestinal microorganisms that possess the ability to degrade resistant plant materials, such as lignocellulose. This is the first study to our knowledge to isolate, characterize, and compare microbial isolates (yeast and bacteria) extracted from the guts of wood-feeding termites (WFT) and lesser waxworms (LWW). The objective was to determine their efficacy in decomposing recalcitrant pollutants, such as low-density polyethylene (LDPE). The isolates belonged to numerous taxonomic groups, as determined by molecular identification; these groups included Bacillus, Citrobacter, Cellulosimicrobium, Rhodococcus, Pseudomonas, Candida, and others. A number of isolates had the potential to degrade LDPE. After 45 days of incubation, the polymer sheets lost 19.8 % of their weight for Bacillus cereus (LDPE-DB2) and 15.4 % of their weight for Candida guilliermondii (LDPE-DY6). Additionally, LDPE degraded by LDPE-DY6 showed a tensile strength loss of 50.3 % compared to that degraded by LDPE-DB2 (58.3 %). During this time, robust biofilm formation was observed on the surfaces of the polymers. Extracellular enzymes such as cutinases, aryl alcohol oxidases, and peroxidases, secreted by specific yeast and bacterial isolates, contribute to the degradation of plastic and recalcitrant biopolymers. Notably, the isolates from LWW demonstrated a greater advantage in this regard than those from WFT. Bacillus cereus, Pseudomonas aeruginosa, Candida guilliermondii, and Sterigmatomyces halophilus were found to have the highest activities in degrading LDPE among the studied WFT and LWW gut-derived symbionts. This study paves the way for a new opportunity to enhance polyethylene degradation by insect gut bacteria and yeasts that may facilitate biotechnological applications for plastic waste remediation.

3D Printed PLA Porous Scaffolds with Engineered Cell Size and Porosity Promote the Effectiveness of the Kelvin Model for Bone Tissue Engineering

AbstractIn this study, the aim is to investigate the effect of engineering the cell size and porosity of 3D‐printed poly lactic acid (PLA) porous scaffolds from the Kelvin model for bone tissue engineering applications. The Kelvin model is used as a bone tissue scaffold with different cell sizes and porosities. PLA, as a biodegradable and biocompatible polymer, is used to fabricate these scaffolds using the FDM technique. A compression test is used to evaluate the mechanical properties of scaffolds. The MTT assay has been used to investigate cell viability. For osteogenic differentiation studies, ALP activity and ARS assays are used. Increasing the porosity reduces the mechanical properties of the scaffold. While increasing the cell size at constant porosity increases the Young's modulus and yield stress in the samples, it is also observed that, in high porosities, the increase in cell size weakens the mechanical properties. Also, Kelvin model scaffolds help the proliferation and osteogenic differentiation of cells and have no toxic effect. It is demonstrated that this approach promotes the effectiveness of the Kelvin architecture for bone tissue engineering. As a result, designing the most suitable model based on cell size and porosity for the treatment process in the targeted area could be promising.

Development of Eco‐Friendly Chitosan‐Dextran Polyblend Electrolyte for Enhanced Performance in Primary Magnesium Batteries

The potential of next‐generation batteries lies in solid biodegradable polymer electrolytes. This research delves into a solid blend polymer electrolyte (SBPE) for magnesium conduction, utilizing a chitosan‐dextran blend matrix doped with magnesium perchlorate (Mg(ClO4)2) salt. The electrolyte films are prepared using a conventional solution casting technique. Through techniques like X‐ray diffraction and Fourier transform infrared spectroscopy, the successful incorporation of Mg(ClO4)2 into the blend matrix is confirmed. Notably, the SBPE containing 30 wt% of Mg(ClO4)2 demonstrates the highest ionic conductivity of 6.99 × 10−4 S cm−1 and a prominent ionic transference number of 0.84. Thermogravimetric analysis is carried out to study thermal stability. Differential scanning calorimetry analysis of the electrolyte systems gives insight into their thermal properties. Additionally, it showcases favorable electrochemical stability of 2.66 V. The oxidation and reduction peaks are observed in the cyclic voltammetry curve of the highest conducting sample. Furthermore, the discharge performance of Mg/(CS + DN + Mg(ClO4)2)/cathode cells is explored with varied cathode materials, illustrating the SBPE's potential for magnesium‐ion batteries. This study unveils a sustainable, biodegradable, and economical electrolyte solution for advanced energy storage systems.

Highly Selective O-Phenylene Bisurea Catalysts for ROP: Stabilization of Oxyanion Transition State by a Semiflexible Hydrogen Bond Pocket.

Organocatalyzed ring-opening polymerization (ROP) is a versatile technique for synthesizing biodegradable polymers, including polyesters and polycarbonates. We introduce o-phenylene bisurea (OPBU) (di)anions as a novel class of organocatalysts that are fast, easily tunable, mildly basic, and exceptionally selective. These catalysts surpass previous generations, such as thiourea, urea, and TBD, in selectivity (kp/ktr) by 8 to 120 times. OPBU catalysts facilitate the ROP of various monomers, achieving high conversions (>95%) in seconds to minutes, producing polymers with precise molecular weights and very low dispersities (Đ ≈ 1.01). This performance nearly matches the ideal distribution expected from living polymerization (Poisson distribution). Density functional theory (DFT) calculations reveal that the catalysts stabilize the oxyanion transition state via a hydrogen bond pocket similar to the "oxyanion hole" in enzymatic catalysis. Both experimental and theoretical analyses highlight the critical role of the semirigid o-phenylene linker in creating a hydrogen bond pocket that is tight yet flexible enough to accommodate the oxyanion transition state effectively. These new insights have provided a new class of organic catalysts whose accessibility, moderate basicity, excellent solubility, and unparalleled selectivity and tunability open up new opportunities for controlled polymer synthesis.

Investigating the Effect of Carbon Nanomaterials Reinforcing Poly(ε-Caprolactone) Printed Scaffolds for Bone Repair Applications.

Scaffolds, three-dimensional (3D) substrates providing appropriate mechanical support and biological environments for new tissue formation, are the most common approaches in tissue engineering. To improve scaffold properties such as mechanical properties, surface characteristics, biocompatibility and biodegradability, different types of fillers have been used reinforcing biocompatible and biodegradable polymers. This paper investigates and compares the mechanical and biological behaviors of 3D printed poly(ε-caprolactone) scaffolds reinforced with graphene (G) and graphene oxide (GO) at different concentrations. Results show that contrary to G which improves mechanical properties and enhances cell attachment and proliferation, GO seems to show some cytotoxicity, particular at high contents.

Materials based on biodegradable polymers chitosan/gelatin: a review of potential applications.

Increased mass manufacturing and the pervasive use of plastics in many facets of daily life have had detrimental effects on the environment. As a result, these worries heighten the possibility of climate change due to the carbon dioxide emissions from burning conventional, non-biodegradable polymers. Accordingly, biodegradable gelatin and chitosan polymers are being created as a sustainable substitute for non-biodegradable polymeric materials in various applications. Chitosan is the only naturally occurring cationic alkaline polysaccharide, a well-known edible polymer derived from chitin. The biological activities of chitosan, such as its antioxidant, anticancer, and antimicrobial qualities, have recently piqued the interest of researchers. Similarly, gelatin is a naturally occurring polymer derived from the hydrolytic breakdown of collagen protein and offers various medicinal advantages owing to its unique amino acid composition. In this review, we present an overview of recent studies focusing on applying chitosan and gelatin polymers in various fields. These include using gelatin and chitosan as food packaging, antioxidants and antimicrobial properties, properties encapsulating biologically active substances, tissue engineering, microencapsulation technology, water treatment, and drug delivery. This review emphasizes the significance of investigating sustainable options for non-biodegradable plastics. It showcases the diverse uses of gelatin and chitosan polymers in tackling environmental issues and driving progress across different industries.

Reactivity of N terminal histidine of peptides towards excipients/impurity of excipients: A case study of liraglutide excipient compatibility study

The selection of quality excipients is a crucial step in peptide formulation development. Apart from excipient incompatibility, process-related impurities or degradants of an excipient can interact with peptide-active pharmaceutical ingredients, forming the interaction products. The formaldehyde has been reported as an impurity of excipient in polyethylene glycol, glycerol, magnesium stearate, microcrystalline cellulose, mannitol, etc. The peptide contains various amino acids such as histidine, lysine, and arginine having free amine groups. These amine groups act as strong nucleophile and can increase the reactivity of peptides. PLGA is the most widely used biodegradable polymer in sustained-release formulations. The hydrolysis of PLGA generates glycolic acid and lactic acid impurities, which can form the interaction product with the amines of peptides. During the formulation development of Liraglutide, we have found few interaction products. The systematic characterization and mechanistic understanding of these interaction products lead us to imidazopyrimidine, glycolyl, and lactolyl moieties. These interaction products have been characterized thoroughly with the use of LC-HRMS, MS/MS, and hydrogen-deuterium exchange mass studies. The study revealed that the reactivity of N-terminal histidine must be considered for formulation development. Moreover, the quality of excipients with respect to presence of impurities must be considered as critical material attributes.

A Kinetic-Based Criterion for Polymer Biodegradability Applicable to Both Accelerated and Standard Long-Term Composting Biodegradation Tests

A Kinetic-Based Criterion for Polymer Biodegradability Applicable to Both Accelerated and Standard Long-Term Composting Biodegradation Tests

Experimental and numerical analysis of natural fillers loaded and E-glass reinforced epoxy sandwich composites

Natural fibers play a crucial role in sandwich composites due to their biodegradability, ease of manufacturing, and ability to reduce pollution. The research aims to develop new biodegradable polymer composites using pine tree leaves (PTL) fillers loaded with epoxy through hand layup technique with different wt. % of PTL fillers. The molded composites were characterized to analyze the crystal size and plane orientations, surface morphology, thermal resistance, and presence of elemental compositions in the PTL filler-loaded epoxy composites through X-ray diffraction (XRD), Field emission scanning electron microscope (FESEM), Energy dispersive analysis (EDX), Differential scanning calorimetry (DSC), and Thermogravimetric analysis (TGA). The 40 wt % of PTL epoxy composites showed a maximum tensile strength of 32 ± 0.5 MPa, a compressive strength of 15 ± 0.5 MPa, a flexural strength of 55 ± 0.5 MPa, and a Shore D hardness of 73 ± 0.5 SHN. The mechanical strength of 40 wt% PTL fillers loaded epoxy composite was enhanced by adding a single and double layer of E-glass fiber on the bottom and top of the PTL fillers loaded epoxy composite, achieving a maximum tensile strength of 76 ± 0.5 MPa. The 40 wt% PTL fillers loaded double E-glass fiber on the bottom and top of the PTL fillers loaded epoxy sandwich composite attained the maximum tensile strength of 156 ± 0.5 MPa, compressive strength of 29 ± 0.5 MPa, flexural strength of 220 ± 0.5 MPa, and Shore D hardness of 79 ± 0.5 SHN. The PTL fillers loaded and reinforced double E-glass fiber epoxy sandwich composite would be used in low-strength structural applications.

The effect of polylactic acid-based blend films modified with various biodegradable polymers on the preservation of strawberries

Polylactic acid (PLA) has garnered much attention in the field of fruit and vegetable packaging. Despite its poor flexibility and water resistance, PLA film faces challenges in being used for strawberry storage and freshness preservation due to its inability to maintain flavor quality. In this study, a series of PLA-based modified films was produced by melt blending and extrusion cast processing with PLA as the main component, along with flexible biodegradable polyesters or polycarbonate as the secondary component. First, five different biodegradable polymers were used to investigate the effect of the flexibility and barrier properties of different dispersed phases on the morphology, mechanical properties, and water vapor barrier of PLA-based blend films. Next, the impact on the freshness of strawberries was assessed through examination of fruit color and weight, as well as the levels of O2 and CO2 in the packaging bags. The results showed that the size of the dispersed phase and interfacial bonding with PLA were the key factors determining the mechanical and barrier properties of the blend films. The PLA-polycaprolactone (PCL) blend showed the best compatibility among them, with PCL having the smallest dispersion size (D=0.58 µm), higher toughness than the other four PLA blends, and greater enhancement of PLA. Additionally, it exhibited a similar rate of quality loss in strawberry preservation compared to commercial PE. As a result, the color and luster were more completely preserved. The results of this study may help the future development of degradable plastics, to reduce environmental pollution.

Optimizing Polyhydroxyalkanoate production using a novel Bacillus paranthracis isolate: A response surface methodology approach

Microorganisms have emerged as promising resources for producing economical and sustainable bioproducts like Polyhydroxyalkanoate (PHA), a biodegradable polymer that can replace synthetic plastics. In this study, we screened a novel isolate, Bacillus paranthracis RSKS-3 strain, to produce PHA from sewage water, identifying it using Whole Genome Sequence. This study represents the first report on optimizing PHA production using B. paranthracis RSKS-3, employing Design Expert 12.0 software. Our findings reveal that four factors (temperature, inoculum size, potassium dihydrogen phosphate, and magnesium sulfate) significantly affect PHA production in the Plackett-Burman design experiment. Through Response Surface Methodology, we optimized PHA production to 0.647 g/L with specific values for potassium dihydrogen phosphate (0.55 %), inoculum size (3 %), magnesium sulfate (0.055 %), and a temperature of 35 °C, in agreement with the predicted value of 0.630 g/L. This optimization resulted in a substantial 13.29-fold increase in PHA production from 0.34 g/L to 4.52 g/L, underscoring the promising role of B. paranthracis RSKS-3 in eco-friendly PHA production and advancing sustainable bioproduct development.

Experimental and Computational Study of Modified Biopolymer Xanthan Gum with Synthetic Vinyl Monomers for Enhanced Oil Recovery

AbstractUtilizing xanthan gum, a biodegradable polymer, in enhanced oil recovery (EOR) is imperative wherever there is a need for innovation in oil production that is both cost-effective and environmentally friendly. Xanthan, chosen for its natural sourcing, availability, controllability, eco-friendliness, and biodegradability, proves resilient against harsh reservoir conditions owing to its rigid structure and elongated polysaccharide chains. This study investigates two modified xanthan gum composites, achieved by grafting with synthetic vinyl monomers through emulsified polymerization. Spectroscopic characterization using FTIR and 1H-NMR, along with surface morphology analysis via atomic force microscopy (AFM) and thermal behavior screening through TGA analysis, elucidates the properties of these modified composites. Rheological behavior under reservoir conditions, including stress scanning and viscosity/shear rate dependency, was evaluated. Material modeling with the Materials Studio program simulated the equilibrium adsorption of xanthan and modified biopolymer chains on SiO2-quartz crystal to assess wettability alteration. Simulation results indicate that XG-g-AM, MMA&TEVS exhibit greater stability and surface coverage with more negative electrostatic energies compared to XG and XG-g-AM&MMA. The laboratory runs on a sandstone-packed model to identify the disclosed XG-g-AM&MMA and XG-g-AM, MMA&TEVS biopolymers as promising EOR candidates and wettability modifiers in challenging sandstone reservoirs, as per experimental outcomes.

Small Particles, Big Potential: Polymeric Nanoparticles for Drug Delivery in Parkinson's Disease.

Despite the availability of a number of efficacious treatments for Parkinson's disease, their limitations and drawbacks, particularly related to low brain bioavailability and associated side effects, emphasize the need for alternative and more effective therapeutic approaches. Nanomedicine, the application of nanotechnology in medicine, has received considerable interest in recent years as a method of effectively delivering potentially therapeutic molecules to the brain. In particular, polymeric nanoparticles, constructed from biodegradable polymer, have shown great promise in enhancing therapeutic efficacy, reducing toxicity, and ensuring targeted delivery. However, their clinical translation remains a considerable challenge. This article reviews recent in vitro and in vivo studies using polymeric nanoparticles as drug and gene delivery systems for Parkinson's disease with their challenges and future directions. We are also particularly interested in the technical properties, mechanism, drugs release patterns, and delivery strategies to overcome the blood-brain barrier. © 2024 International Parkinson and Movement Disorder Society.

Key Points of Design and Risk Analysis in Production for Biodegradable Heart Occluder

Biodegradable heart occluder uses a biodegradable medical polymer material to replace or completely replace the metal material. After completing the repair function of the heart defect, the device is gradually degraded and safely absorbed by the human tissue. So it may minimize the risk of long-term complications that traditional metal heart occluder causing in the body after implantation. Based on the quality management concept of the entire lifecycle of medical device, this article briefly introduces design and development, as well as the product realization of biodegradable heart occluder. It analyzes the main risk points in design and production, and corresponding suggestions have been put forward. These suggestions are combined with the medical device good manufacturing practice and the appendix of implantable medical equipment to provide a reference for regulators and industry professionals.