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The elevated use of petroleum-based polymers to manufacture single-use disposable face masks is a serious environmental concern that has detrimental effects on the ecosystem. The research on using biodegradable facemasks is promising to reduce the environmental impacts of the single-use nondegradable facemask. A reusable cloth-based facemask with effective filtration could benefit society. Many studies suggest polyvinyl alcohol (PVA), polybutylene adipate terephthalate (PBAT), and polylactic acid (PLA) as viable biopolymers for facemask filter layer fabrication. In this work, an electrospun filter layer inserts with PVA, PBAT, and PLA polymers were produced by depositing electrospun nanofibers on non-woven cotton layers followed by conventional sealing. The fabricated filter inserts were used in cloth-based facemasks and were tested for filtration efficiencies and breathability. PVA facemask insert showed the best performance with 66.7% filtration efficiency and breathability of 0.66 m bar, whereas the lowest filtration efficiency was found for PBAT electrospun filter medium. The relation between filter membrane morphology and facemask performance indicates that a smaller diameter and uniform morphology results in better filtration and breathability of the facemask filter inserts. Highlights * Petroleum-based facemasks harm ecosystems. * Biodegradable facemasks reduce environmental impact. * Electrospun nanofibers of polyvinyl alcohol (PVA), polybutylene adipate terephthalate, and polylactic acid on cotton. * PVA insert showed 66.7% filtration and 0.66 m bar breathability. * Smaller, uniform fibers enhance filtration and breathability. KEYWORDS biodegradable polymers, breathability, electrospinning, facemask, filtration efficiency, 1 | INTRODUCTION The airborne transmission of infectious diseases such as the SARS-COVID-19 virus is a serious problem that has severely hampered public health and the economy. (1-3) The transmission [...]

Polymer nanocomposites have been widely exploited in different engineering applications like high-voltage engineering application. This is mainly associated with the ease at which they can be tailored toward specific applications. In the present work, alumina- and organoclay-based nanofillers were separately incorporated in cross-linked polyethylene (XLPE). Different formulations of the XLPE nanocomposites were fabricated with the help of an internal mixer after which they were molded to produce test specimens. The effect of nanofiller variation (0.25 and 0.5 wt% loading) on the electrical treeing phenomenon is reported herein. It was observed that the incorporation of 0.5 wt% alumina significantly enhances the tree inception voltage. In addition, compared to 0.25 wt% alumina-, 0.25 and 0.5 wt% organoclay-filled XLPE nanocomposites, 0.5 wt% alumina was found to lower the length and growth of the electrical tree, as well as the expansion coefficient of the XLPE nanocomposite. KEYWORDS crosslinked polyethylene, electrical treeing, polymer nanocomposites, tree inception voltage, 1 | INTRODUCTION In recent years, there have been increased interest in inorganic-nanoparticles filled polymer materials as polymeric insulators. During its early development, neat polymers were first used and later [...]

Polymer materials have garnered significant attention due to their exceptional mechanical properties and diverse industrial applications. Understanding the glass transition temperature (Tg) of polymers is critical to prevent operational failures at specific temperatures. Traditional methods for measuring Tg, such as differential scanning calorimetry (DSC) and dynamic mechanical analysis, while accurate, are often time-consuming, costly, and susceptible to inaccuracies due to random and uncertain factors. To address these limitations, the aim of the present study is to investigate the potential of Simplified Molecular Input Line Entry System (SMILES) as descriptors in simple machine learning models to predict Tg efficiently and reliably. Five models were utilized: k-nearest neighbors (KNNs), support vector regression (SVR), extreme gradient boosting (XGBoost), artificial neural network (ANN), and recurrent neural network (RNN). SMILES descriptors were converted into numerical data using either One Hot Encoding (OHE) or Natural Language Processing (NLP). The study found that SMILES inputs with fewer than 200 characters were inadequate for accurately describing compound structures, while inputs exceeding 200 characters diminished model performance due to the curse of dimensionality. The ANN model achieved the highest R2 value of 0.79; however, the XGB model, with an R2 value of 0.774, exhibited the highest stability and shorter training times compared to other models, making it the preferred choice for Tg prediction. The efficiency of the OHE method over NLP was demonstrated by faster training times across the KNN, SVR, XGB, and ANN models. Validation of new polymer data showed the XGB model's robustness, with an average prediction deviation of 9.76 from actual Tg values. These findings underscore the importance of optimizing SMILES conversion methods and model parameters to enhance prediction reliability. Future research should focus on improving model accuracy and generalizability by incorporating additional features and advanced techniques. This study contributes to the development of efficient and reliable predictive models for polymer properties, facilitating the design and application of new polymer materials. [ABSTRACT FROM AUTHOR]

Filler components play a crucial role as thermo‐mechanical reinforcement to the epoxy‐based solder mask, ensuring effective insulation and passivation. This study investigates the impact of different inorganic filler types (talc, silica (SiO2), boron nitride (BN) and barium sulfate (BaSO4)) and loadings (5 and 15 wt%) on the tensile and thermal properties of the epoxy composites. The composites were blended, cast and thermally cured. Of these composites, only 15 wt% SiO2/epoxy composite exhibits notable increments in both tensile strength and modulus, surpassing unfilled epoxy by 11.65% and 31.9%, respectively. It also displays the highest elongation at break, supported by small particle size, high specific surface area and minimal void volume fraction. For thermal tests, the addition of all fillers increases the storage modulus in both glassy and rubbery regions, especially 15 wt% talc/epoxy composite with 30.09% increment at 25 °C. Additionally, all fillers raise the glass transition temperature (Tg), notably improving it by 9 °C in the 15 wt% BN/epoxy composite. Moreover, their inclusion generally enhances the onset decomposition temperature (Tonset) and reduces weight loss during decomposition. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

The printed electronics (PEs) market has witnessed substantial growth, reaching a valuation of USD 10.47 billion in the previous year. Driven by its extensive use in a multitude of applications, this growth trend is expected to continue with a projected compound annual growth rate of 22.3% from 2022 to 2032. Compared to screen printing, the adoption of inkjet printing (IJP) technology to manufacture PEs has been limited to laboratory‐scale research only. The fact that IJP's inability to maintain consistent high‐resolution quality over large printing areas has made transitioning IJP for commercial production arduous. Most of the previous literatures have focused on holistic discussion on material design for IJP, but this review provides insight into key aspects in material processing up to printing optimization to realize high‐resolution PEs. This review also highlights the challenges in controlling the functional ink properties and their interaction with the substrate as well as printing parameters to deliver the desired quality of the droplets and final prints. Imminent application of IJP in PEs and future perspectives are also included in this review. [ABSTRACT FROM AUTHOR]

In recent years, bionanocomposites have received growing attention in science and industry due to their renewability, biodegradability and superior mechanical properties. Nanocellulose is another promising material that use as a reinforcement filler for bionanocomposite materials due to its lightweight, high surface area, high mechanical strength, high aspect ratio and low density. Different nanocellulose loading, sources, surface modification/functionalization and properties of nanocellulose are important in the production of bionanocomposites. In general, nanocellulose reinforced PLA bionanocomposite offers enhancement in tensile strength and elastic modulus. However, only minimal nanocellulose loadings are required for optimal results due to the incompatibility between the hydrophilic nanocellulose and hydrophobic PLA. This paper reviews the sources of nanocellulose and the properties of nanocellulose with a focus on the tensile and morphological properties of PLA bionanocomposites. Applications of nanocellulose in various industries are discussed in this article. This review article provides some important information. First, this study reviewed the application of nanostructured cellulose in biodegradable polymers. There are two types of nanostructured cellulose: nanocrystalline cellulose (NCC) and nanofibrillated cellulose (NFC). Second, the status on articles published on nanocellulose and PLA/nanocellulose over the past 10 years is reported. Third, the authors of this paper implemented a holistic and critical review to provide a comprehensive understanding of the different properties between NCC and NFC, the application of nanocellulose in bionanocomposites, as well as the properties of PLA and PLA bionanocomposites. Moreover, the influence of NCC and NFC on the tensile and morphological properties of bionanocomposites is covered in this article. KEYWORDS bionanocomposites, morphological properties, nanocrystalline cellulose, nanofibrillated cellulose, polylactic acid, tensile properties, 1 | INTRODUCTION Of late, the use of petroleum-based materials has generated disposal and environmental issues, for instance, the increase of the amount of municipal solid waste. [1-5] In order [...]

Recently, thoughtful disagreements between scientists concerning environmental issues including the use of renewable materials have enhanced universal awareness of the use of biodegradable materials. Polylactic acid (PLA) is one of the most promising biodegradable materials for commercially replacing nondegradable materials such as polyethylene terephthalate and polystyrene. The main advantages of PLA production over the conventional plastic materials is PLA can be produced from renewable resources such as corn or other carbohydrate sources. Besides, PLA provides adequate energy saving by consuming C[O.sub.2] during production. Thus, we aim to highlight recent research involving the investigation of properties of PLA, its applications and the four types of potential PLA degradation mechanisms. In the first part of the article, a brief discussion of the problems surrounding use of conventional plastic is provided and examples of biodegradable polymers currently used are provided. Next, properties of PLA, and (Poly[L-lactide]), (Poly[D-lactide]) (PDLA) and (Poly[DL-lactide]) and application of PLA in various industries such as in packaging, transportation, agriculture and the biomedical, textile and electronic industry are described. Behaviors of PLA subjected to hydrolytic, photodegradative, microbial and enzymatic degradation mechanisms are discussed in detail in the latter portion of the article. KEYWORDS hydrolytic, microbial and enzymatic degradation, photodegradation, poly (lactic acid), 1 | INTRODUCTION In recent decades, the use of fossil fuel-based plastics has produced production and waste management problems. These products are low cost, [1,2] versatile and highly resistant to [...]