Biodegradable and biocompatible soy protein/polymer/adhesive sticky nano-textured interfacial membranes for prevention of esca fungi invasion into pruning cuts and wounds of vines

Study on electrospinning of wheat gluten: A review

Electrospinning has attracted extensive attention among various nanofabrication technologies owing to its ability to produce nanofiber structures with unique properties, such as high specific surface area and porosity, as well as tunable fiber morphology and mechanical properties. The most representative spinning raw materials include natural polymers and synthetic polymers. Owing to the sustainable development strategies, more and more researchers focus on natural polymers. Among natural polymers, wheat gluten (WG) nanofibers have recently attracted much attention owing to its high specific surface area, superior biocompatibility, and unique viscoelasticity. This review summarizes the composition and characteristics of WG, the physical and chemical indicators of a WG electrospinning solution, the main influencing factors in the WG electrospinning process and a characterizations of WG nanofibers. Finally, the review also outlines the applications of WG nanofibers in drug release, biological scaffold, and active food packaging.

Agro-Industrial Plant Proteins in Electrospun Materials for Biomedical Application

Plant proteins are receiving a lot of attention due to their abundance in nature, customizable properties, biodegradability, biocompatibility, and bioactivity. As a result of global sustainability concerns, the availability of novel plant protein sources is rapidly growing, while the extensively studied ones are derived from byproducts of major agro-industrial crops. Owing to their beneficial properties, a significant effort is being made to investigate plant proteins' application in biomedicine, such as making fibrous materials for wound healing, controlled drug release, and tissue regeneration. Electrospinning technology is a versatile platform for creating nanofibrous materials fabricated from biopolymers that can be modified and functionalized for various purposes. This review focuses on recent advancements and promising directions for further research of an electrospun plant protein-based system. The article highlights examples of zein, soy, and wheat proteins to illustrate their electrospinning feasibility and biomedical potential. Similar assessments with proteins from less-represented plant sources, such as canola, pea, taro, and amaranth, are also described.

Biodegradable Electrospun Nanofiber Membranes as Promising Candidates for the Development of Face Masks

Aerosol particles, such as the widespread COVID-19 recently, have posed a great threat to humans. Combat experience has proven that masks can protect against viruses; however, the epidemic in recent years has caused serious environmental pollution from plastic medical supplies, especially masks. Degradable filters are promising candidates to alleviate this problem. Degradable nanofiber filters, which are developed by the electrospinning technique, can achieve superior filtration performance. This review focuses on the basic introduction to air filtration, the general aspects of face masks, and nanofibers. Furthermore, the progress of the state of art degradable electrospun nanofiber filters have been summarized, such as silk fibroin (SF), polylactic acid (PLA), chitosan, cellulose, and zein. Finally, the challenges and future development are highlighted.

Molecular simulations explain the exceptional thermal stability, solvent tolerance and solubility of protein-polymer surfactant bioconjugates in ionic liquids

Proteins complexed electrostatically with polymer surfactants constitute a viscous liquid by themselves, called the solvent-free protein liquid (SFPL). A solution of SFPL in a room temperature ionic liquid (PS-IL) offers the protein hyperthermal stability, higher solubility and greater IL tolerance. A generic understanding of these protein-polymer systems is obtained herein through extensive atomistic molecular dynamics simulations of three different enzymes (lipase A, lysozyme and myoglobin) under various conditions. Along with increased intra-protein hydrogen bonding, the surfactant coating around the proteins imparts greater thermal stability, and also aids in screening protein-IL interactions, endowing them IL tolerance. The reduced surface polarity of the protein-polymer bioconjugate and hydrogen bonding between the ethylene glycol groups of the surfactant and the IL cation contribute to the facile solvation of the protein in its PS-IL form. The results presented here rationalize several experimental observations and will aid in the improved design of such hybrid materials for sustainable catalysis.

Electrospun Polymer Materials with Fungicidal Activity: A Review

In recent years, there has been special interest in innovative technologies such as polymer melt or solution electrospinning, electrospraying, centrifugal electrospinning, coaxial electrospinning, and others. Applying these electrokinetic methods, micro- or nanofibrous materials with high specific surface area, high porosity, and various designs for diverse applications could be created. By using these techniques it is possible to obtain fibrous materials from both synthetic and natural biocompatible and biodegradable polymers, harmless to the environment. Incorporation of low-molecular substances with biological activity (e.g., antimicrobial, antifungal) is easily feasible. Moreover, biocontrol agents, able to suppress the development and growth of plant pathogens, have been embedded in the fibrous materials as well. The application of such nanotechnologies for the creation of plant protection products is an extremely promising new direction. This review emphasizes the recent progress in the development of electrospun fungicidal dressings and their potential to be applied in modern agriculture.

Eco-Friendly Hybrid PLLA/Chitosan/Trichoderma asperellum Nanomaterials as Biocontrol Dressings against Esca Disease in Grapevines

Fungi constitute the largest number of plant pathogens and are responsible for a range of serious plant diseases. Phaeomoniella chlamydospora (P. chlamydospora) and Phaeoacremonium aleophilum (P. aleophilum) are the main fungal pathogens causing esca disease in grapevines. On the other hand, there are beneficial microorganisms such as Trichoderma spp., which are able to control the growth of many phytopathogens. In the present study, innovative, eco-friendly hybrid nanomaterials were created by electrospinning PLLA, followed by the formation of a film of chitosan/Trichoderma asperellum (T. asperellum) spores on the fibers. The polymer carrier used in this study plays an active role in ensuring the viability of the biological agent during storage and, when placed in contact with moisture, ensures the agent’s normal development. Oligochitosan, as well as low molecular weight and high molecular weight chitosan, were used. The effects of chitosan molecular weight on the dynamic viscosity of chitosan solutions, film formation, mechanical properties, spore incorporation and growth were studied. The morphology of the prepared nanomaterials, and the presence of a film based on the formation of chitosan/T. asperellum spores on the PLLA fibers, were examined using scanning electron microscopy (SEM). The surface chemical compositions of the fibrous materials were studied using attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR). The mechanical properties of the obtained materials were also tested. The microbiological screening that was performed revealed that the eco-friendly hybrid nanomaterials incorporated with the beneficial microorganism, T. asperellum, to hamper the growth of the pathogenic P. chlamydospora and P. aleophilum fungi. The suppression rate depended on the viscosity of the chitosan solution used for the film formation. The use of oligochitosan resulted in the most effective infection of the material with T. asperellum spores. The environmentally friendly hybrid nanomaterials obtained in this study—in which the bioagent was embedded—are promising bioactive dressings for protecting grapevines against esca disease.

Electrospun 5-Chloro-7-iodo-8-hydroxyquinoline (Clioquinol)-Containing Poly(3-hydroxybutyrate)/Polyvinylpyrrolidone Antifungal Materials Prospective as Active Dressings against Esca

Esca is a grapevine disease known for centuries which pertains to the group of so-called vine trunk diseases. Phaeomoniella chlamydospora (P. chlamydospora) and Phaeoacremonium aleophilum (P. aleophilum) are the two main fungal pathogens associated with esca. Novel fibrous materials with antifungal properties based on poly(3-hydroxybutyrate) (PHB), polyvinylpyrrolidone (PVP) and 5-chloro-7-iodo-8-hydroxyquinoline (clioquinol, CQ) were developed. One-pot electrospinning (“in” strategy) or electrospinning in conjunction with electrospraying (“on” strategy) were applied to obtain the materials. The materials’ morphology and their surface chemical composition were examined using scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR). CQ incorporated in the bulk of the fibers or in PVP particles deposited on the fibers was in the amorphous phase, which was confirmed by differential scanning calorimetry (DSC) and X-ray diffraction analysis (XRD). The in vitro release of CQ depended on the composition of the electrospun materials and on their design. The performed microbiological screening revealed that, unlike the non-loaded mats, the fibrous mats loaded with CQ were effective in inhibiting the growth of the pathogenic P. chlamydospora and P. aleophilum fungi. Therefore, the created materials are promising as active dressings for grapevine protection against esca.

Nanotechnology: recent advances in viticulture and enology

Nowadays, nanoscience is a leading modern science that has a major impact on the food, pharmaceutical, and agriculture sectors. Several nanomaterials show a great potential for use during vine growing and winemaking processes. In viticulture, nanotechnology can be applied to protect vines against phytopathogens and to improve grape yield and quality. Thus, nanotechnology may allow the use of lesser amounts of phytochemical compounds, reducing environmental impact and promoting a more sustainable agriculture. And in winemaking, nanomaterials and nanodevices can be used to control the growth of spoilage microorganisms and to reduce or remove undesirable compounds, such as ethyl phenols (4-ethylphenol and 4-ethylguaiacol), biogenic amines, and tartaric acid, and so on, as well as to facilitate some technological processes (i.e. in wine filtration to eliminate microorganisms). This review summarizes recent studies with applications of nanotechnology in viticulture in order to facilitate agronomic management and optimize grape production and in enology to improve wine quality and safety. © 2021 Society of Chemical Industry.

Electrospun Polymer-Fungicide Nanocomposites for Grapevine Protection

Nowadays, diseases in plants are a worldwide problem. Fungi represent the largest number of plant pathogens and are responsible for a range of serious plant diseases. Esca is a grapevine disease caused mainly by fungal pathogens Phaeomoniella chlamydospora (P. chlamydospora) and Phaeoacremonium aleophilum (P. aleophilum). The currently proposed methods to fight esca are not curative. In this study, polymer composites based on biodegradable polymer containing chemical fungicides with antifungal activity were successfully prepared by electrospinning. The obtained materials were hydrophobic with good mechanical properties. In vitro studies demonstrated that the fungicide release was higher from PLLA/K5N8Q fibrous mats (ca. 72% for 50 h) compared to the released drug amount from PLLA/5-Cl8Q materials (ca. 52% for 50 h), which is due to the better water-solubility of the salt. The antifungal activity of the fibrous materials against P. chlamydospora and P. aleophilum was studied as well. The incorporation of the fungicide in the biodegradable fibers resulted in the inhibition of fungal growth. The obtained materials are perspective candidates for the protection of vines from the penetration and growth of fungal pathogens.

Polymer-Based Nanotherapeutics for Burn Wounds

Burn wounds are complex and intricate injuries that have become a common cause of trauma leading to significant mortality and morbidity every year. Dressings are applied to burn wounds with the aim of promoting wound healing, preventing burn infection and restoring skin function. The dressing protects the injury and contributes to recovery of dermal and epidermal tissues. Polymer-based nanotherapeutics are increasingly being exploited as burn wound dressings. Natural polymers such as cellulose, chitin, alginate, collagen, gelatin and synthetic polymers like poly (lactic-co-glycolic acid), polycaprolactone, polyethylene glycol, and polyvinyl alcohol are being obtained as nanofibers by nanotechnological approaches like electrospinning and have shown wound healing and re-epithelialization properties. Their biocompatibility, biodegradability, sound mechanical properties and unique structures provide optimal microenvironment for cell proliferation, differentiation, and migration contributing to burn wound healing. The polymeric nanofibers mimic collagen fibers present in extracellular matrix and their high porosity and surface area to volume ratio enable increased interaction and sustained release of therapeutics at the site of thermal injury. This review is an attempt to compile all recent advances in the use of polymer-based nanotherapeutics for burn wounds. The various natural and synthetic polymers used have been discussed comprehensively and approaches being employed have been reported. With immense research effort that is currently being invested in this field and development of proper characterization and regulatory framework, future progress in burn treatment is expected to occur. Moreover, appropriate preclinical and clinical research will provide evidence for the great potential that polymer-based nanotherapeutics hold in the management of burn wounds.

An accurate and dual-effective body slimming method through a soluble microneedle patch with variable temperature

Obesity is a chronic and recurrent disease with potential risks. Traditional weight-loss methods (like exercises, surgeries, oral drugs, etc.) have shown different side effects. In this experiment, the microneedle (MN) patch was selected as the drug carrier of the weight-loss drug Rosiglitazone (Rosi). Besides, melanin was added to enhance the photo-thermal effect and accelerate the release of drugs to the target fat region under near-infrared (NIR) light. Afterwards, with exterior cold stimulation, the significant and accurate effect of body slimming could be achieved. This combination of soluble MN patches and variable temperatures provides an attractive nonsurgical method for future accurate body slimming management.

Electrospinning Proteins for Wound Healing Purposes: Opportunities and Challenges

With the growth of the aging population worldwide, chronic wounds represent an increasing burden to healthcare systems. Wound healing is complex and not only affected by the patient's physiological conditions, but also by bacterial infections and inflammation, which delay wound closure and re-epithelialization. In recent years, there has been a growing interest for electrospun polymeric wound dressings with fiber diameters in the nano- and micrometer range. Such wound dressings display a number of properties, which support and accelerate wound healing. For instance, they provide physical and mechanical protection, exhibit a high surface area, allow gas exchange, are cytocompatible and biodegradable, resemble the structure of the native extracellular matrix, and deliver antibacterial agents locally into the wound. This review paper gives an overview on cytocompatible and biodegradable fibrous wound dressings obtained by electrospinning proteins and peptides of animal and plant origin in recent years. Focus is placed on the requirements for the fabrication of such drug delivery systems by electrospinning as well as their wound healing properties and therapeutic potential. Moreover, the incorporation of antimicrobial agents into the fibers or their attachment onto the fiber surface as well as their antimicrobial activity are discussed.

Continuous Flow Composite Membrane Catalysts for Efficient Decomposition of Chemical Warfare Agent Simulants

Continuous and safe decomposition of chemical warfare agents (CWAs) is a critical requirement to protect both soldiers and citizens and to eliminate the stockpiles after the cold war. The Zr-based metal-organic framework (Zr-MOF) has been known as the most effective catalyst for decomposing CWAs, especially the most fatal nerve agents, however, its low processability due to the powder form limits its expansion to actual military applications. To this end, the composite membrane catalysts (CMCs) comprising the Zr-MOF (UiO-66 catalyst) and nylon 6 nanofiber (porous supporter) are developed by the simple integration of electrospray and electrospinning, resulting in selective immobilization of UiO-66 on the surface of the nylon 6 nanofibers. These strategical benefits of CMCs gave super catalytic durability including recyclability over five times without decreasing the catalytic activity for the decomposition of methyl paraoxon (MPO), a simulant of the nerve agent, in the presence of N-ethylmorpholine (N-EM), which was not achieved in the original particulate UiO-66. Because of the excellent physical and chemical stabilities of CMCs, the CMC with 56 wt % of UiO-66 (CMC56) decomposed 198 g of MPO within an hour in the continuous flow system with a flow rate of 21.6 mL h^-1. This study highlights the important strategies in designing the feasible membrane-type catalysts with superior catalytic activity and robust durability for decomposing CWAs in the continuous flow system.

Electrospun Eco-Friendly Materials Based on Poly(3-hydroxybutyrate) (PHB) and TiO2 with Antifungal Activity Prospective for Esca Treatment

Esca is a type of grapevine trunk disease that severely affects vine yield and longevity. Phaeomoniella chlamydospora (P. chlamydospora) is one of the main fungi associated with esca. The aim of the present study was to obtain eco-friendly materials with potential antifungal activity against P. chlamydospora based on biodegradable and biocompatible poly(3-hydroxybutyrate) (PHB), nanosized TiO₂-anatase (nanoTiO₂), and chitosan oligomers (COS) by conjunction of electrospinning and electrospraying. One-pot electrospinning of a suspension of nanosized TiO₂ nanoparticles in PHB solution resulted in materials in which TiO₂ was incorporated within the fibers (design type “in”). Simultaneous electrospinning of PHB solution and electrospraying of the dispersion of nanosized TiO₂ in COS solution enabled the preparation of materials consisting of PHB fibers on which TiO₂ was deposited on the fibers’ surface (design type “on”). Several methods including scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction analysis (XRD), thermogravimetric analyses (TGA) and water contact angle were utilized to characterize the obtained materials. The incorporation of nanoTiO₂ in the PHB fibers, as well as nanoTiO₂ deposition onto the surface of the PHB fibers resulted in increased roughness and hydrophobicity of the obtained composite fibrous materials. Moreover, TiO₂-on-PHB fibrous material exhibited complete inhibition of fungal growth of P. chlamydospora. Therefore, the obtained eco-friendly fibrous materials based on PHB and nanoTiO₂ are promising candidates for protection against esca in agriculture.

Electrospun 5-chloro-8-hydroxyquinoline-Loaded Cellulose Acetate/Polyethylene Glycol Antifungal Membranes Against Esca

Esca is one of the earliest described diseases in grapevines and causes trunk damage and the sudden wilting of the entire plant; it is caused mainly by the species Phaeomoniella chlamydospora (P. chlamydospora) and Phaeoacremonium aleophilum (P. aleophilum). In practice, there are no known curative approaches for fighting esca directly, which is a huge problem for preserving vineyards. Micro- and nanofibrous membranes from cellulose acetate (CA) and cellulose acetate/polyethylene glycol (CA/PEG) containing 5-chloro-8-hydroxyquinolinol (5-Cl8Q) were successfully prepared by electrospinning. The surface morphologies and optical and mechanical properties of the membranes were characterized by using scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), ultraviolet-visible spectroscopy (UV-Vis), water contact angle measurements and mechanical tests. It was found that the bioactive compound release was facilitated by PEG. The antifungal activities of the obtained materials against P. chlamydospora and P. aleophilum were studied. We have demonstrated that 5-Cl8Q is an efficient and sustainable antifungal agent against P. chlamydospora and P. aleophilum. Moreover, for the first time, the present study reveals the possibility of using electrospun polymer membranes containing 5-Cl8Q which impede the penetration and growth of P. chlamydospora and P. aleophilum. Thus, the obtained fibrous materials can be suitable candidates for plant protection against diverse fungi.

Soy Protein/Cellulose Nanofiber Scaffolds Mimicking Skin Extracellular Matrix for Enhanced Wound Healing

Historically, soy protein and extracts have been used extensively in foods due to their high protein and mineral content. More recently, soy protein has received attention for a variety of its potential health benefits, including enhanced skin regeneration. It has been reported that soy protein possesses bioactive molecules similar to extracellular matrix (ECM) proteins and estrogen. In wound healing, oral and topical soy has been heralded as a safe and cost-effective alternative to animal protein and endogenous estrogen. However, engineering soy protein-based fibrous dressings, while recapitulating ECM microenvironment and maintaining a moist environment, remains a challenge. Here, the development of an entirely plant-based nanofibrous dressing comprised of cellulose acetate (CA) and soy protein hydrolysate (SPH) using rotary jet spinning is described. The spun nanofibers successfully mimic physicochemical properties of the native skin ECM and exhibit a high water retaining capability. In vitro, CA/SPH nanofibers promote fibroblast proliferation, migration, infiltration, and integrin β1 expression. In vivo, CA/SPH scaffolds accelerate re-epithelialization and epidermal thinning as well as reduce scar formation and collagen anisotropy in a similar fashion to other fibrous scaffolds, but without the use of animal proteins or synthetic polymers. These results affirm the potential of CA/SPH nanofibers as a novel wound dressing.

Packing of metalized polymer nanofibers for aneurysm embolization

Aneurysmal subarachnoid hemorrhage (SAH) is the extravasation of blood into the subarachnoid space and is fatal in most cases. Platinum coils have been used to fill the hemorrhage site and prevent the extravasation of blood. Here we explored the use of Pt-coated polymer nanofibers (NF) to prevent blood extravasation and were able to achieve improved results in vitro. The polymer nanofibers were produced via electrospinning and were subsequently electroplated with Pt, resulting in metalized nanofibers. These nanofibers were installed within a microfluidic channel, and the resulting reduction in the permeability was evaluated using a fluid similar to blood. Based on the obtained results, these newly developed nanofibers are expected to decrease the operation cost for SAH, owing to their reduced size and low material cost. Furthermore, it is expected that these nanofibers will be used in a smaller amount during SAH operation while having the same preventive effect. This should reduce the operational risk associated with the multiple steps required to place the Pt coils at the SAH site. Finally, the underlying hydrodynamic mechanism responsible for the reduced permeability of the synthesized nanofibers is described.

Advances in self-healing materials based on vascular networks with mechanical self-repair characteristics

Here, we review the state-of-the-art in the field of engineered self-healing materials. These materials mimic the functionalities of various natural materials found in the human body (e.g., the healing of skin and bones by the vascular system). The fabrication methods used to produce these "vascular-system-like" engineered self-healing materials, such as electrospinning (including co-electrospinning and emulsion spinning) and solution blowing (including coaxial solution blowing and emulsion blowing) are discussed in detail. Further, a few other approaches involving the use of hollow fibers are also described. In addition, various currently used healing materials/agents, such as dicyclopentadiene and Grubbs' catalyst, poly(dimethyl siloxane), and bisphenol-A-based epoxy, are described. We also review the characterization methods employed to verify the physical and chemical aspects of self-healing, that is, the methods used to confirm that the healing agent has been released and that it has resulted in healing, as well as the morphological changes induced in the damaged material by the healing agent. These characterization methods include different visualization and spectroscopy techniques and thermal analysis methods. Special attention is paid to the characterization of the mechanical consequences of self-healing. The effects of self-healing on the mechanical properties such as stiffness and adhesion of the damaged material are evaluated using the tensile test, double cantilever beam test, plane strip test, bending test, and adhesion test (e.g., blister test). Finally, the future direction of the development of these systems is discussed.

Nanomedicine and advanced technologies for burns: Preventing infection and facilitating wound healing

According to the latest report from the World Health Organization, an estimated 265,000 deaths still occur every year as a direct result of burn injuries. A widespread range of these deaths induced by burn wound happens in low- and middle-income countries, where survivors face a lifetime of morbidity. Most of the deaths occur due to infections when a high percentage of the external regions of the body area is affected. Microbial nutrient availability, skin barrier disruption, and vascular supply destruction in burn injuries as well as systemic immunosuppression are important parameters that cause burns to be susceptible to infections. Topical antimicrobials and dressings are generally employed to inhibit burn infections followed by a burn wound therapy, because systemic antibiotics have problems in reaching the infected site, coupled with increasing microbial drug resistance. Nanotechnology has provided a range of molecular designed nanostructures (NS) that can be used in both therapeutic and diagnostic applications in burns. These NSs can be divided into organic and non-organic (such as polymeric nanoparticles (NPs) and silver NPs, respectively), and many have been designed to display multifunctional activity. The present review covers the physiology of skin, burn classification, burn wound pathogenesis, animal models of burn wound infection, and various topical therapeutic approaches designed to combat infection and stimulate healing. These include biological based approaches (e.g. immune-based antimicrobial molecules, therapeutic microorganisms, antimicrobial agents, etc.), antimicrobial photo- and ultrasound-therapy, as well as nanotechnology-based wound healing approaches as a revolutionizing area. Thus, we focus on organic and non-organic NSs designed to deliver growth factors to burned skin, and scaffolds, dressings, etc. for exogenous stem cells to aid skin regeneration. Eventually, recent breakthroughs and technologies with substantial potentials in tissue regeneration and skin wound therapy (that are as the basis of burn wound therapies) are briefly taken into consideration including 3D-printing, cell-imprinted substrates, nano-architectured surfaces, and novel gene-editing tools such as CRISPR-Cas.

Protection of Vine Plants against Esca Disease by Breathable Electrospun Antifungal Nonwovens

The harmful Esca disease in vine plants caused by wood-inhabiting fungi including Phaeomoniella chlamydospora (Pch) is spreading all across the world. This disease leads to poor vine crops and a slow decline or to a sudden dieback of the vine plants. The pruning wounds of vine plants are the main entry point for Pch. While model experiments with aerosol particles recommend electrospun nonwovens as a suitable barrier to block Pch, tests with living spores show clearly that only electrospun fibrous nonwovens do not prevent Pch invasion. However it is found, that with antifungal additives electrospun nonwovens could be applied successfully for blocking of Pch to infect the substrate. Thereby, a highly useful concept for the protection of vine plants against Esca disease is provided which could also serve as a concept for related plant diseases.

Solution-Blown Core-Shell Self-Healing Nano- and Microfibers

Self-healing microfibers with core-shell geometry were studied. A commercial binary epoxy was encased in solution-blown polymer nano-/microfibers in the 0.2-2.6 μm diameter range. The core-shell microfibers were formed by coaxial nozzles, which encapsulated the epoxy resin and its hardener in separate cores. Solution blowing, the fiber-forming process used in this work, was at least 30 times faster than the electrospinning method used previously and has already been scaled up to the industrial level. These core-shell microfibers show self-healing capability, in which epoxy and hardener are released from the cores of damaged fibers, resulting in polymerization. The epoxy used had a higher strength and shorter solidification time than poly(dimethylsiloxane) (PDMS) used previously. Also, the larger fiber diameters in the present study facilitated faster release of the epoxy resin and its hardener from the fiber cores, shortening the solidification time in comparison to the previous studies. Blister tests were conducted, which measured the adhesion energy of microfiber mats to substrates and the cohesion energy between layers of microfiber mats before and after fatigue damage followed by self-healing.

Self-healing Nanofiber-Reinforced Polymer Composites. 2. Delamination/Debonding and Adhesive and Cohesive Properties

The capacity for core-shell nanofiber mats containing healing agents (resin monomer and cure) in their cores to adhere to a substrate was studied using blister testing. After extended periodic bending, the adhesion energy was measured, and the effect of self-healing on the composite's delamination from the substrate was considered. In addition, the cohesion of two layers of the self-healing nanofibers was examined using blister testing and compared to that of ordinary nanofiber mats. The damage inflicted by prolonged periodic bending to the interface of the two nanofiber mats was demonstrated to have self-healed, and the cohesion energy was measured.

Endogenous Cu and Zn nanocluster-regulated soy protein isolate films: excellent hydrophobicity and flexibility

Special bio-films from SPI regulated by endogenous Cu and Zn nanoclusters have excellent hydrophobicity and flexibility.