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The purpose of this paper is to introduce a novel face mask prototype having a superabsorbent nanofibrous coating with a homogenous distribution.

Superabsorbent nanofibers were manufactured via electrospinning method using Poly(vinyl alcohol)/superabsorbent polymer (PVA/SAP) aqueous polymer solutions and they were simultaneously coated onto face masks in order to develop their virus protection and comfort properties. Absorbency, air permeability, Fourier Transform Infrared Spectroscopy (FT-IR) and SEM investigations were carried out for characterization.

SEM investigations revealed that face masks were homogenously coated with nanofibers. Picks obtained from FT-IR spectra proved that all mask samples have PVA/SAP content indicating their absorbent feature. Liquid absorption capacity and air permeability tests have shown that nanofiber coating increased the hydrophilicity of face masks while air permeability decreased in reverse. Final prototype has been found to be promising for industrial, scientific and medical applications with its improved protection and comfort characteristics.

The implication of the research is to investigate the morphological, physical and transfer difference of face masks that are coated with nanofibers and uncoated face masks. This is useful in selection of the right face mask with optimum surface, absorbency and transfer properties.

Compared to commercial product in the market, the face mask developed within the study has a more regularly distributed nanofiber coating.

The purpose of this paper is to prepare superabsorbent polymers (SAPs) based on acrylic acid, which is considered hygroscopic material to incorporate in rubber formulation, which results in producing moisten rubber that is used as roofing sheets.

SAPs were synthesized via free radical bulk polymerization technique using different content of cross-linker N, N'-methylenebisacrylamide and potassium persulfate. Differential scanning calorimeter, thermal gravimetric analysis, Fourier transform infrared spectroscopy and transmission electron microscopy were used to characterize SAPs and confirmed the formation of cross-linked hydrogel structure. The water absorbency and the gel fraction for sodium polyacrylate (NaPA) were investigated. Then, the influence of obtained NaPA on the swelling behavior of the prepared natural rubber (NR) compound has been discussed.

Absorption characteristics and gel fraction of NaPA were found to depend on the content of the cross-linker in the system. SAPs are used to improve the absorbance behavior and performance of the NR to produce, roofing sheets using in hot weather. The morphology of the obtained rubber compound was well-explained by using a scanning electron microscope.

The research provides a simple way to produce moisten rubber that can be used as a roofing sheet to overcome warm weather.

Moisten rubber roofing sheets provide a low-cost option in many developing countries with hot climates, and thus, help save the environment from global warming.

Absorbent disposable products, such as diapers and sanitary napkins, are mostly one-time use items and designed to absorb and retain body fluids and solid waste. The present research work deals with the development and characterization of baby diapers made from four different fibrous compositions namely, pure bamboo, pure cotton, bamboo/cotton (70/30) and bamboo/cotton (50/50). Antibacterial activity tests have been carried out on baby diapers against S.aureus and E.coli. The strongest antibacterial activity in terms of reduction of the organism is found in diapers produced from pure bamboo fibre and the weakest antibacterial activity is found in cotton diapers. Superabsorbent polymer (SAP), namely, sodium polyacrylate is incorporated into the diapers to enhance their absorption capacity. The diapers are subjected to tests such as absorption capacity, liquid strike-through, acquisition time under load and diaper rewet under load to study their performance. Upon an analysis of the results, it is found that the performance of diapers produced from a bamboo/cotton (70/30) fibre blend is superior in comparison to the other ones.

The purpose of this paper is to prepare and optimize the preparation conditions of some new hydrogels and in addition, evaluate their water absorbance at different mediums and their ability to remove ions from aqueous solutions.

Cellulose was extracted from depithed bagasse at two different pulping conditions; 3 and 6 hours cooking times, pulp (I) and (II), respectively. These pulps, in addition to cotton linter for comparison, were grafted with acrylamide followed by cross‐linking with glutaraldehyde. The networks were partially hydrolyzed and the structures of products (before and after hydrolysis) were studied using FTIR, SEM, TGA and X‐ray. The optimum preparation conditions were identified, before and after hydrolysis, to achieve maximum absorbance and the ability of prepared hydrogels to remove ions from solutions was investigated.

Maximum level of absorption was recorded using hydrogels prepared with monomer concentration =0.8 mol/l, cross‐linker concentration =0.01 mol/l, reaction time =2 hours and temperature =65°C. Hydrogels prepared using pulp (I) showed the best absorbance behavior and a tendency to remove ions from water.

The ability of the prepared gels to remove ions from water could be further investigated to evaluate the ability of their use in a multi‐filtration system for water treatment.

This piece of work has suggested a simple way to convert an agricultural waste to hydrogel able to remove metal ions from water.

Consuming this type of waste reduces the risks resulting from its burning in some countries, such as Egypt, that produce large amounts of it.

In this paper, low cost hydrogels, with expected value in water treatment, were prepared using agricultural wastes. They have shown better reactivity than gels prepared using pure cellulosic materials (cotton linter).

Menstruation poses psycho-physiological challenges globally due to a lack of awareness, unhygienic practices and social stigma. This paper aims to assess the existing body of research on menstrual health and hygiene (MHH) worldwide.

This study focuses on seminal works published in the Scopus Database from 1946 to 2023 for extensive bibliometric analysis, involving 756 bibliographic records analyzed through Biblioshiny and VOSviewer software. The authors use thematic analysis to identify core research themes and sub-themes, coupled with a critical review of the most highly cited articles within each thematic category.

The research into MHH has consistently grown since 2010, with a notable surge in the past five years. Among all countries, the USA emerges as the most active contributor, boasting the highest number of publications and citations. In terms of organizations, The London School of Hygiene and Tropical Medicine takes the lead with 54 articles. Further, PLOS ONE and Waterlines were the most productive and influential journals, respectively. The thematic analysis identifies key research foci, including tampons, menstrual health, sanitation, hygiene and bleeding.

Further research could be initiated in areas of menstrual education and awareness, menstrual product safety and effectiveness and menstrual disorders and treatments to address the concerns especially encountered by women from developing countries.

This research provides a comprehensive analysis of 77 years of MHH research, offering valuable insights into key areas of concern and guiding future research directions, ultimately addressing critical global health challenges.

This study aims to investigate the mechanical, thermal, melt-flow and morphological behavior of acrylonitrile-butadiene-styrene (ABS)-based composites after bentonite inclusions. Melt mixing is the most preferred production method in industrial scale and basically it has very near processing parameters compared to 3D printing applications. Rheological parameters of ABS and its composites are important for 3D applications. Melt flow behavior of ABS effects the fabrication of 3D printed product at desired levels. Shear thinning and non-Newtonian viscosity characteristics of ABS make viscosity control easier and more flexible for several processing techniques including injection molding, compression molding and 3D printing.

ABS copolymer was reinforced with bentonite mineral (BNT) at four different loading ratios of 5%, 10%, 15% and 20%. ABS/BNT composites were fabricated by lab-scale micro-compounder followed by injection molding process. Mechanical, thermo-mechanical, thermal, melt-flow and morphological properties of composites were investigated by tensile, hardness and impact tests, dynamic mechanical analysis (DMA), thermo-gravimetric analysis (TGA), melt flow index (MFI) test and scanning electron microscopy (SEM), respectively.

Mechanical tests revealed that tensile strength, elongation and hardness of ABS were enhanced as BNT content increased. Glass transition temperature and storage modulus of ABS exhibited increasing trend with the additions of BNT. However, impact strength values dropped down with BNT inclusion. According to MFI test measurements, BNT incorporation displayed no significant change for MFI value of ABS. Homogeneous dispersion of BNT particles into ABS phase was deduced from SEM micrographs of composites. Loading ratio of 15% BNT was remarked as the most suitable candidate among fabricated ABS-based composites according to findings.

The advanced mechanical properties and easy processing characteristics are the reasons for usage of ABS as an engineering plastic. Owing to the increase in its usage for 3D printing technology, the ABS became popular in recent years. The utilization of ABS in this technology is in filament form with various colors and dimensions. This is because of its proper rheological features.

Melt-mixing technique was used as preparation of composites, as this processing method is widely applied in industry. This method is also providing similar processing methodology with 3D printing technology.

According to the literature survey, to the best of the authors’ knowledge, this study is the first research work regarding the melt-flow performance of ABS-based composites to evaluate their 3D printing applications and processability. ABS and BNT containing composites were characterized by tensile, impact and shore hardness tests, DMA, TGA), MFI test and SEM techniques.

The purpose of this study is to prepare composite of chitosan-modified smectite clays consisting of montmorillonite and saponite clay minerals and their urea adsorption–desorption study. Prepared materials were designed for slow-release fertilizer application.

Preparation of the composites was conducted by a simple intercalation of chitosan solution and clay suspension followed by hydrogel beads formation. Physicochemical characterization of materials was performed by X-ray diffraction, gas sorption analysis by using Brunauer–Emmett–Teller surface areas and pore volume, water absorbency and Fourier transform-infrared. Urea adsorption and desorption studies of prepared materials were conducted by using batch method, and the adsorbed and desorbed urea content was analyzed by using high-performance liquid chromatography method.

The results revealed that the composites have higher absorptivity and lower absorptivity toward urea from and into water solution compared to raw clay minerals. Adsorption capacity and slow desorption rate of urea from the composites suggested the potential application of the composites as slow urea-releasing agent.

There are many papers that study the formation of chitosan-clay composites, but the study on the urea adsorption–desorption properties based on chitosan-smectite minerals have not been reported. Intensive study related to physicochemical properties and its related kinetics study is an important basic finding for further applications.

The purpose of this paper is to use alternative polymerisation methods, i.e. UV irradiation to synthesise poly(acrylamide)/montmorillonite nanocomposite and characterise the composite.

Polymer/montmorillonite nanocomposite was synthesised by the polymerisation, induced by UV radiation and the structure of the composite was studied by means of FTIR, NMR(¹³ C, ²⁷Al and ²⁹Si) and X‐ray diffraction.

The poly(acrylamide)/montmorillonite nanocomposite was synthesised by UV irradiation, and its structures showed that the acrylamide was intercalated in the lamina of montmorillonite in bimolecular layers. FTIR and NMR analyses showed that there was no major chemical change of the polymer chain associated with the intercalation. The interaction between montmorillonite and polymer was mainly related with the van der Waals forces and hydrogen bonding, not with the bonding involved with the carbon atoms.

There are few reports on the synthesis and characterisation of polymer/montmorillonite composite prepared with UV radiation.

The alternative synthesis method using UV irradiation can provide a new way for the preparation of montmorillonite/acrylamide nanocomposite for the application in moisture and organic solvent vapour sensors, etc.

This provides a way for the synthesis of polymer/montmorillonite nanocomposite using polymerisation induced by UV radiation, which can be used in the thin membrane preparation for sensor and special application. Characterisation of the material revealed the structure of the nanocomposite, which would be helpful for the study of structure design and property improvement.

This paper aims to discuss the use of the sensor material in coating to detect defects which can cause corrosion on metal substrate. This coating consists of sodium polyacrylate (SP) to detect the presence of water and fluorescence substance 2-[4-(piperidin-1-yl)-5H-chromeno-[2,3-d]pyrimidin-2-yl]phenol [benzopyranopyrimidine (BPP)] to detect crack formation.

The coating resin is a mixture of poly(methyl methacrylate) (PMMA) and poly (methyl vinyl ether-alt-maleic anhydride). The additives are used to provide a visual indicator to the observer for when the coating exhibits any defects, so that quick action can be taken before corrosion develops further. SP has absorbent properties and expand when in contact with water, while BPP exhibits high luminous intensity in its solid form that is easily perceivable when exposed to UV. PVM/MA was used as the binder with ethanol as the solvent. The resistance of this coating towards water penetration was investigated using electrochemical impedance spectroscopy (EIS). The coating’s performance was observed in terms of visible optical appearance.

The sensor coating developed in this project serves as visual aid to the observer through the expansion of SP and high fluorescence of BPP material after the top coat is physically damaged. These findings are in provision of preventive measures that can be taken in case of top coat failure.

The resistance of the coating that contained SP could not be investigated with EIS due to its ability to expand immediately when in contact with liquids.

The coating developed in this study may be to detect corrosion.

The sensor material used has not been previously studied in applications to detect the presence of water or used to detect crack formation.

This study aims to develop a polymer cement-based waterproof coating with self-healing capability to efficiently and intelligently solve the building leakage caused by cracking of waterproof materials, along with excellent durability to prolong its service life.

Ion chelators are introduced into the composite system based on ethylene vinyl acetate copolymer emulsion and ordinary Portland cement to prepare self-healing polymer cement-based waterproof coating. Hydration, microstructure, wettability, mechanical properties, durability, self-healing performance and self-healing products of polymer cement-based waterproof coating with ion chelator are investigated systematically. Meanwhile, the chemical composition of self-healing products in the crack was examined.

The results showed that ion chelators could motivate the hydration of C₂S and C₃S, as well as the formation of hydration products (C-S-H gel) of the waterproof coating to improve its compactness. Compared with the control group, the waterproof coating with ion chelator had more excellent water resistance, alkali resistance, thermal and UV aging resistance. When the dosage of ion chelator was 2%, after 28 days of curing, cracks with a width of 0.29 mm in waterproof coating could fully heal and cracks with a width of 0.50 mm could achieve a self-healing efficiency of 72%. Furthermore, the results reveal that the self-healing product in the crack was calcite crystalline CaCO₃.

A novel ion chelator was introduced into the composite coating system to endow it with excellent self-healing ability to prolong its service life. It has huge application potential in the field of building waterproofing.