The current day target for material scientists and researchers is developing a wholesome material to satisfy the parameters such as durability, manufacturability, low cost, and lightweight. Extensive ...research studies are ongoing on the possible application of polymer matrix composites in engineering and technology, since these materials have an edge over conventional materials in terms of performance. Hybridization of reinforcements is considered to be a better option to enhance the efficiency and performance of composite materials. Accordingly, research studies focus on the surface treatment of natural fibers and the addition of nanofillers (natural or synthetic) by industry and academia to take the properties and application of composites to the next level. This review purely focuses on the influence of fillers on the properties of composites along with the probable application of filler-based polymer composites.
Next‐generation microelectronics and electrical power systems call for high‐energy‐density dielectric polymeric materials that can operate efficiently under elevated temperatures. However, the ...currently available polymer dielectrics are limited to relatively low working temperatures. Here, the solution‐processable polymer nanocomposites consisting of readily prepared Al2O3 fillers with systematically varied morphologies including nanoparticles, nanowires, and nanoplates are reported. The field‐dependent electrical conduction of the polymer nanocomposites at elevated temperatures is investigated. A strong dependence of the conduction behavior and breakdown strength of the polymer composites on the filler morphology is revealed experimentally and is further rationalized via computations. The polymer composites containing Al2O3 nanoplates display a record capacitive performance, e.g., a discharged energy density of 3.31 J cm−3 and a charge–discharge efficiency of >90% measured at 450 MV m−1 and 150 °C, significantly outperforming the state‐of‐the‐art dielectric polymers and nanocomposites that are typically prepared via tedious, low‐yield approaches.
High‐temperature dielectric polymer nanocomposites with facilely prepared nanostructured Al2O3 fillers exhibit remarkable electrical energy storage and discharge capabilities at elevated temperatures and high electric fields, outperforming state‐of‐the‐art polymer dielectrics. The significant impact of the filler morphology on conduction behavior and capacitive performance of the composites is revealed.
Today, there is an urgent demand to develop all solid‐state lithium‐ion batteries (LIBs) with a high energy density and a high degree of safety. The core technology in solid‐state batteries is a ...solid‐state electrolyte, which determines the performance of the battery. Among all the developed solid electrolytes, composite polymer electrolytes (CPEs) have been deemed as one of the most viable candidates because of their comprehensive performance. In this review, the limitations of traditional solid polymer electrolytes and the recent progress of CPEs are introduced. The effect and mechanism of inorganic fillers to the various properties of electrolytes are discussed in detail. Meanwhile, the factors affecting ionic conductivity are intensively reviewed. The recent representative CPEs with synthetic fillers and natural clay‐based fillers are highlighted because of their great potential. Finally, the remaining challenges and promising prospects are outlined to provide strategies to develop novel CPEs for high‐performance LIBs.
This review summarizes the limitations of typical solid polymer electrolytes and the development of composite polymer electrolytes (CPEs) with inorganic fillers, discussing the enhancement effects and mechanisms of inorganic fillers on various properties of CPEs. The factors affecting the ionic conductivities of CPEs due to inorganic fillers are highlighted. CPEs with representative synthetic and natural clay‐based inorganic fillers are introduced.
Gel polymer electrolytes (GPEs) have attracted abundant attentions due to its higher ion conductivity and better compatibility with electrode than the inorganic solid-state electrolytes and safer ...than the liquid electrolytes. In this work, sodium conductive Na3Zr2Si2PO12 nanoparticles modified PVDF-HFP/PMMA/TPU-based GPEs are prepared and its application performances in sodium ions batteries (SIBs) are demonstrated. The addition of Na3Zr2Si2PO12 filler decreases the crystallinity of polymer matrix and improves the porosity of GPEs membranes, resulting in the increasing of liquid electrolyte uptake. As a result, the Na3Zr2Si2PO12 filler modified GPEs delivers enhanced ion conductivity as high as 2.83 × 10−3 S cm−1 with a small activation energy of ~0.039 eV and enlarged electrochemical window width of 5.16 V. Application in SIBs, high first discharge capacity of 92.7 mAh·g−1 at 0.5C and promising capacity retention capability (99.2% after 100 cycles) as well as excellent rate performance (83.9 mAh·g−1 at 5C) are recorded for the obtained GPEs. These results suggest that the performances of PVDF-HFP/PMMA/TPU-based GPEs can be enhanced obviously by adding conductive Na3Zr2Si2PO12 filler, promoting the practical application of GPEs in energy storage devices.
•PVDF-HFP/PMMA/TPU-Na3Zr2Si2PO12 composite gel polymer electrolyte was fabricated.•Ionic conductivity of GPE was enhanced with the presence of Na3Zr2Si2PO12 filler.•Na3Zr2Si2PO12 filler decreased the crystallinity and enlarged the porosity of GPE.•GPE delivered competitive electrochemical performances applied in SIBs.
Summary
Background
Hyaluronic acid is a widely available, biocompatible, polysaccharide with distinguishing physiochemical properties which inspire its application throughout several fields of ...medicine.
Objective
We aim to investigate the application of hyaluronic acid and its effectiveness throughout several fields of medicine, including several therapies administered and prescribed by general health practitioners.
Methods
We conducted a systematic review on randomized controlled trials about the physiochemical properties of hyaluronic acid and its application through primary care. Studies included in this review were peer reviewed and met our inclusion criteria.
Findings
Factors were clustered into the following: uses throughout several fields of medicine, physiochemical properties, bioavailability, tolerance, effectiveness, and adverse effects. Therapies with hyaluronic acid provided long‐lasting, pain relieving, moisturizing, lubricating, and dermal filling effect. Tissue hydration, elasticity, and durability improved.
Conclusions
Adjunct therapy with hyaluronic acid provides longer‐lasting therapeutic effect when compared to the use of glucocorticosteroids and NSAIDs in osteoarthritic chronic diseases, is well‐established in ophthalmology due to its lubricating properties for the corneal endothelium, and improves tissue hydration and cellular resistance to mechanical damage in aesthetic dermatology, and has marginal adverse effects. Several trials indicated its role in tumor markers, liver diseases, and in pharmaceuticals, but further research would be necessary to draw conclusive results in those fields.
Objective
The scar's appearance and psychological burden are the most esthetically challenging issues in acne vulgaris. This study investigated the effectiveness and safety profile of combined ...radiofrequency‐assisted subcision, which, even though effective on both Icepeak and Rolling subtypes, is only mildly effective on boxcar lesions, and polycaprolactone‐based dermal filler with collagen stimulation potency in managing atrophic postacne scars.
Methods
Our quasi‐experimental single‐arm study, after the inclusion of 10 cases over the age of 18 with moderate to severe mixed atrophic facial acne scarring, was carried out in two 3‐month separate sessions, during and after the intended intervention of which the experienced lesion improvements and also adverse events were documented. Moreover, all cases were followed for 3 months after the last session, evaluating the differences in the mentioned outcomes.
Results
We found the combined intervention to be highly effective in improving the intended outcomes, with the total number of acne lesions (p‐value < 0.001), along with the total number of Ice peak (p‐value = 0.002), Rolling (p‐value < 0.001), and boxcar (p‐value = 0.023) lesions demonstrating statistically significant changes.
Conclusion
Radiofrequency‐assisted subcision combined with polycaprolactone‐based dermal fillers can be an effective intervention in managing postacne scars. However, we recommend that randomized clinical trials with larger sample sizes be carried out for a more precise conclusion.
The potential of using ground birch (
Ehrh.) bark as an eco-friendly additive in urea-formaldehyde (UF) adhesives for plywood manufacturing was investigated in this work. Five-ply plywood panels were ...fabricated in the laboratory from beech (
L.) veneers bonded with UF adhesive formulations comprising three addition levels of birch bark (BB) as a filler (10%, 15%, and 20%). Two UF resin formulations filled with 10% and 20% wheat flour (WF) were used as reference samples. The mechanical properties (bending strength, modulus of elasticity and shear strength) of the laboratory-fabricated plywood panels, bonded with the addition of BB in the adhesive mixture, were evaluated and compared with the European standard requirements (EN 310 and EN 314-2). The mechanical strength of the plywood with the addition of BB in the adhesive mixture is acceptable and met the European standard requirements. Markedly, the positive effect of BB in the UF adhesive mixture on the reduction of formaldehyde emission from plywood panels was also confirmed. Initially, the most significant decrease in formaldehyde release (up to 14%) was measured for the plywood sample, produced with 15% BB. After four weeks, the decrease in formaldehyde was estimated up to 51% for the sample manufactured with 20% BB. The performed differential scanning calorimetry (DSC), thermal gravimetric analysis (TGA), and derivative thermogravimetry (DTG), also confirmed the findings of the study. As this research demonstrated, BB as a waste or by-product of wood processing industry, can be efficiently utilized as an environmentally friendly, inexpensive alternative to WF as a filler in UF adhesive formulations for plywood manufacturing.
We present the first reported cases of delayed inflammatory reactions (DIR) to hyaluronic acid (HA) dermal fillers after exposure to the COVID-19 spike protein. DIR to HA is reported to occur in the ...different scenarios including: secondary to poor injection technique, following dental cleaning procedures, following bacterial/viral illness, and after vaccination. In this report of 4 cases with distinct clinical histories and presentations: one case occured following a community acquired COVID-19 infection, one case occured in a study subject in the mRNA-1273 clinical phase III trial, one case occurred following the first dose of publically available mRNA-1273 vaccine (Moderna, Cambridge MA), and the last case occurred after the second dose of BNT162b2 vaccine (Pfizer, New York, NY). Injectable HA dermal fillers are prevalent in aesthetic medicine for facial rejuvenation. Structural modifications in the crosslinking of HA fillers have enhanced the products’ resistance to enzymatic breakdown and thus increased injected product longevity, however, have also led to a rise in DIR. Previous, DIR to HA dermal fillers can present clinically as edema with symptomatic and inflammatory erythematous papules and nodules. The mechanism of action for the delayed reaction to HA fillers is unknown and is likely to be multifactorial in nature. A potential mechanism of DIR to HA fillers in COVID-19 related cases is binding and blockade of angiotensin 2 converting enzyme receptors (ACE2), which are targeted by the SARS-CoV-2 virus spike protein to gain entry into the cell. Spike protein interaction with dermal ACE2 receptors favors a pro-inflammatory, loco-regional TH1 cascade, promoting a CD8+T cell mediated reaction to incipient granulomas, which previously formed around residual HA particles. Management to suppress the inflammatory response in the native COVID-19 case required high-dose corticosteroids (CS) to suppress inflammatory pathways, with concurrent ACE2 upregulation, along with high-dose intralesional hyaluronidase to dissolve the inciting HA filler. With regards to the two vaccine related cases; in the mRNA-1273 case, a low dose angiotensin converting enzyme inhibitor (ACE-I) was utilized for treatment, to reduce pro-inflammatory Angiotensin II. Whereas, in the BNT162b2 case the filler reaction was suppressed with oral corticosteroids. Regarding final disposition of the cases; the vaccine-related cases returned to baseline appearance within 3 days, whereas the native COVID-19 case continued to have migratory, evanescent, periorbital edema for weeks which ultimately subsided.
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