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Silicon-containing groups were introduced into fluoroacrylate polymer to further improve the comprehensive performance of pressure-sensitive adhesive (PSA) for expanded polytetrafluoroethylene (ePTFE) bonding.

A series of silicon-containing fluorinated acrylic copolymers were synthesized through free radical solution polymerization with vinyloxy trimethylsilane, allyltrimethylsilane, 3-(trimethoxysilyl)propyl methacrylate or 1,3,5-tris(3,3,3-trifluoropropyl) methylcyclotrisiloxane as silicon monomers, and comprehensive performance of the copolymers was evaluated based on Fourier transform infrared (FTIR) spectroscopy, X-ray photoelectron spectroscopy (XPS), gel permeation chromatography, glass transition temperatures (T_g), differential scanning calorimetry, thermogravimetric analysis, water contact angle, the track, 180° peel strength, and shear holding power.

Based on the FTIR and XPS results, it is confirmed that the silicon monomers were successfully introduced into the fluorinated acrylate copolymer. XPS analysis indicated that the silicon groups had the tendency to enrich on the surface of the film, thereby reducing the F content on the film surface. The glass transition temperatures (T_g) of the PSAs increased when silicon monomers were introduced, while the thermal stability declined. The contact angles of the acrylic PSA films were increased with the introduction of silicon monomers. From the perspective of bonding performance, the track, 180° peel strength and shear holding power decreased to varying degrees compared to silicon-free PSA, except significantly elevated holding power with MPS as the silicon monomer.

Silicon-containing fluorinated acrylic copolymers were synthesized, and the comprehensive performance was evaluated as PSAs of ePTFE for the first time.

The traditional VeoVa10-VAc copolymer latex, which prepared via the emulsion polymerization of the mixed monomers of VAc and VeoVa10, has the poor water resistance and thermal stability because of the migration of the conventional emulsifier molecules and the low bond energy of C-C bond. The purpose of this work is that the fluorinated monomer is used to modify the latex. The film of the resultant latex has the C-F bond with high bond energy and low surface energy, which can effectively improve the heat resistance and water resistance of the resultant film. In addition, the reactive emulsifier is used to replace the conventional emulsifier. The drawbacks of the conventional emulsifier molecules migrate and desorb can be avoided when the polymer latex is stored, thereby also improving the water resistance.

The modified VAc-VeoVa10 latex has been successfully synthesized via the semi-continuous seeded emulsion polymerization, which VAc and VeoVa10 is used as the main monomers and HFMA was used as the functional monomer. KPS and reactive surfactants of SE-10 were used as the initiator and emulsifier, respectively. The structure of resultant latex film was characterized by Fourier transform infrared spectroscopy (FTIR). The latex films were tested by thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and contact angle (CA). The particle size and its distribution of the latex were measured by the nano particle size analyzer.

The factors that had an influence on the properties of the latex and the film were investigated in detail. The stability of the resultant latex is good. The average particles of the latex and its distribution are small and uniform, respectively. In comparison with the conventional latex film, the thermal stability and hydrophobicity of the resultant latex film are improved obviously.

The resultant latex can be used in both the waterborne interior and exterior wall coatings, pickering stabilized waterborne polymer dispersions, polymer powders, environmentally friendly polymer-modified waterproof mortar and other fields, which can be satisfied with the high demand of thermal stability and hydrophobicity.

The modification of poly (VAc-VeoVa10) by reactive surfactant and fluorinated monomer is seldom reported. In this study, the fluorinated poly (VAC-VeoVa) latex is prepared via the reactive surfactants, which VAc and VeoVa10 is used as the main monomers and hexafluorobutyl methacrylate is used as the functional monomer. Potassium persulfate (KPS) and allyl nonyl phenoxy propyl alcohol polyoxyethylene ether ammonium sulfate are used as the initiator and emulsifier, respectively.

This study investigates the influence of trading mechanisms on cross-market integration between stocks and corporate bonds on the Tel Aviv Stock Exchange (TASE) during the COVID-19 crisis. Unlike the worldwide practice of trading corporate bonds on an over-the-counter (OTC) market, TASE uses a limit-order-book (LOB) for both stocks and bonds, potentially creating unique volatility dynamics through direct information spillover. We analyze the volatility dynamics and spillover effects between TASE’s stock and corporate bond markets.

We employ an exponential general autoregressive conditional heteroskedastic (EGARCH)(1,1) model to assess the impact of stock market fear, measured by implied volatility, on Tel-Bond 20 Index returns and volatility. A bivariate diagonal Baba-Engle-Kraft-Kroner (BEKK) model is also applied to capture time-series integration and cross-volatility spillovers between the TA-35 Index (stocks) and the Tel-Bond 20 Index (corporate bonds), especially during financial stress.

The EGARCH model reveals a significant contagion effect, with increased stock market fear lowering corporate bond returns and increasing bond volatility. It also indicates a leverage effect, where negative shocks disproportionately amplify bond volatility. Diagonal BEKK results confirm strong cross-market volatility persistence, especially during crises, highlighting substantial financial contagion between stocks and bonds in TASE. While TASE’s market design improves the overall market quality, these findings underscore the LOB trading mechanism in facilitating financial contagion and systemic risk.

The LOB trading in TASE facilitates direct information flow, intensifying volatility spillover and cross-market integration, with the degree of integration fluctuating based on market conditions. Investors and managers should consider alternative hedging strategies during volatile periods, as stock market sentiment significantly impacts bond stability. Regulators should assess how trading mechanisms affect market integration and risk, especially during periods of distress.

This study offers new insights into how trading mechanisms influence cross-market dynamics, contributing to the literature on market design and financial contagion.

The construction industry’s pursuit of sustainable and high-performance materials has led to the exploration of alternative aggregates and innovative additives. This paper investigates the combined influence of recycled aggregates (RA) and nano TiO₂ particles on M20 and M30 concretes, addressing ecological concerns and seeking to improve material properties. RA, sourced from construction and demolition waste, presents a sustainable solution to alleviate the environmental impact associated with traditional virgin aggregates (VA). However, challenges related to the mechanical strength and durability often hinder the widespread use of RA in concrete. This study aims to bridge this gap by exploring the reinforcing potential of nano TiO₂ particles.

Nanomaterial such as TiO₂ is known for its photocatalytic properties and reinforcement capabilities and has emerged as a promising additive in construction materials. The investigation herein involves the incorporation of nano TiO₂ at percentages of 0.5% and 1% in both VA- and RA-based M20 and M30 concretes. Comprehensive series of tests on mechanical, durability and microstructural properties are conducted for each concrete mix.

Results unequivocally indicate that the addition of TiO₂ significantly improves the properties of concrete, with RA-based concrete exhibiting performance comparable to that of VA-based counterparts. This breakthrough suggests a viable application of RA with TiO₂ in construction projects, promoting sustainability without compromising performance. Following experimental analyses, linear regression and multiple linear regression analyses are used to establish predictive equations correlating interfacial transition zone (ITZ) thickness with TiO₂ percentage, compressive strength, tensile strength, flexural strength and chloride penetration.

These equations serve as valuable tools for predicting ITZ thickness in future concrete formulations based on specified parameter quantities, thereby contributing to informed decision-making in sustainable construction practices. The findings of this study have the potential to contribute to the improvement of environmentally conscious construction methods while also improving the performance and durability of concrete structures.

The paper aims to design the optimum formulation of the nano-titanium dioxide (TiO2) hydrophilic coating system using the synthetic polypropylene glycol (PPG), which can create the reflection and absorption property.

TiO2 nanoparticles are used as fillers, and PPG has been blended at the proper ratio of 1PPG: 0.2TiO2. The prepared resin has been applied onto the glass substrate at different numbers of glass immersions during the dip-coating fabrication process. One-time glass immersion is labeled as T1 coating, two-time glass immersion is labeled as T2 coating and three-time glass immersion is labeled as T3 coating. All the prepared coating systems were left dry at ambient temperature.

T3 coating showed the lowest reading of WCA value at 40.50°, due to higher surface energy at 61.73 mN/m. The T3 coating also shows the greatest absorbance property among the prepared coating systems among the prepared coating. In terms of reflectance property, the T2 coating system has great reflectance in UV region and near-infrared region, which is 16.47% and 2.77 and 2.73%, respectively. The T2 coating also has great optical transmission about 75.00% at the visible region.

The development of thermal insulation coating by studying the relationship between convection heat and reflectance at different wavelengths of incident light.

The developed coating shows high potential for glass window application.

The application of the hydrophilic coating on light absorption, reflectance and transmission at different wavelengths.

The purpose of this study is to develop a protective coating system on mild steel panel incorporating epoxidized natural rubber with acrylic polyol resin.

In this work, a novel attempt is made to develop binder coatings using epoxidized natural rubber-based material and an organic resin (acrylic resin) for corrosion protection on metal substrate. Seven different samples of multifunctional coatings are developed by varying the compositions of epoxidized natural rubber (ENR) and acrylic resin. The properties of the developed coatings have been characterized using analytical methods such as Fourier transform infrared spectroscopy (FTIR) and electrochemical impedance spectroscopy (EIS). EIS has been carried out for 30 days to evaluate the corrosion resistance after immersing into 3.5 wt.% of sodium chloride. Cross hatch cut tester (CHT) has been used to study the adhesive properties. UV–Visible Spectroscopy (UV–Vis) was also used to assess changes in the coating-film transparency of the natural rubber-based coating systems in this study.

The developed coatings have formed uniform layer on the substrate. CHT results show excellent adhesion of the coatings. Higher concentrations of ENR have higher transparency level, which reduces when the acrylic concentration increases. FTIR analysis confirms the crosslinking that occurred between the components of the coatings. Based on the impedance data from EIS, the incorporation of natural rubber can be an additive for the corrosion protection, which has the coating resistance values well above 108Ω even after 30 days of immersion.

The blending method provides a simple and practical solution to improve the strength and adhesion properties of acrylic polyol resin with epoxidized natural rubber. There is still improvement needed for long-term applications.

The work has been conducted in our laboratory. The combination of natural rubber-based materials and organic resins is a new approach in coating research.

The purpose of this study is to develop a green corrosion inhibitor (GCI) from the parthenium hysterophorus (PHS) leaf and identifying its efficiency in corrosion inhibition of AZ31 alloy.

GCI from PHS leaf is extracted with the aid of Soxhlet apparatus and analysed through Fourier transform infrared spectroscopy (FTIR) and phytochemical tests to identify the functional groups and chemical compounds present. Inhibition efficiency (IE) of PHS extract is identified through polarization analysis and immersion tests in which concentration of PHS extract (0–300 ppm) and temperature (303–353 K) is varied.

Maximum IE of 84% is exhibited by the prepared PHS extract at a concentration of 250 ppm at 303 K and further addition diminishes IE. The developed GCI is found effective in room temperature (303 K) as it exhibits lower IE when temperature increased. Both physical and chemical absorption mechanisms were identified for PHS extract over AZ31 surface, whereas FTIR and SEM analysis confirms the development of passivation layer.

Development of GCI from the leaf of a weed (PHS) that disturbs the ecosystem and identifying its efficiency in preventing corrosion of AZ31 under saline environment.

This study aims to explore the possibility of using magnetic biochar composite (MBCC) derived from Heglig tree bark (HTB) powder (agricultural solid waste) and cobalt ferrite (CoFe₂O₄, CFO) for oil spill removal from seawater surface.

One-pot co-precipitation route was used to synthesize MBCC. The prepared materials were characterized by X-ray diffraction, scanning electron microscopy-energy dispersive X-ray spectroscopy, Fourier transform infrared spectroscopy. The densities of the prepared materials were also estimated. Crude, diesel engine and gasoline engine oils were used as seawater pollutant models. The gravimetric oil removal (GOR) method was used for removing oil spills from seawater using MBCC as a sorbent material.

The obtained results revealed that the prepared materials (CFO and MBCC) were able to remove the crude oil and its derivatives from the seawater surface. Besides, when the absorbent amount was 0.01 g, the highest GOR values for crude oil (31.96 ± 1.02 g/g) and diesel engine oil (14.83 ± 0.83 g/g) were obtained using MBCC as an absorbent. For gasoline engine oil, the highest GOR (27.84 ± 0.46 g/g) was attained when CFO was used as an absorbent.

Oil spill removal using MBCC derived from cobalt ferrite and HTB. Using tree bark as biomass (eco-friendly, readily available and low-cost) for magnetic biochar preparation also is a promising method for minimizing agricultural solid wastes (e.g. HTB) and obtaining value-added-products.

This study aims to describe the conversion of rice straw (RS) as an agricultural plant waste to high-performance cationic flocculant for kaolin clay suspension in wastewater treatment as an alternative to synthetic ones.

This was done by grafting rice straw after pretreatment with acrylamide (Aam) using microwave irradiation technique without using an initiator in an open vessel container for wastewater treatment. Radiation time, monomer and rice straw pulp concentration as well as microwave power were scrutinized to examine their impact on maximizing the graft yield %. Application of the resultant copolymers as flocculants for kaolin clay suspension was willful by studying the foremost influences inducing the flocculation process, for instance, flocculent dose, pH, stirring speed and extent of grafting.

It is seen from the obtained results that both FTIR, SEM, X-Ray diffraction, Thermo gravimetric analysis and Zeta potential confirmed the formation of the cationic amide group onto the graft copolymer chain in comparison with the ungrafted one; the microwave initiation method proved to be a very efficient tool concerning maximizing the graft yield % with no harsh chemicals used for initiating grafting; the flocculation efficiency of the prepared copolymers augmented by increasing the flocculant dose, pH and stirring speed to a maximum value signified at 2.0 g, 6.0 and 75 r/min, respectively, then decreased thereafter while increased by increasing the extent of grafting within the range studied; the flocculant reserved high flocculation efficiency even after five cycles of flocculation/regeneration; preliminary bridging mechanism demonstrating the attraction between the kaolin anionic suspended particles and cationic poly (Aam)-rice straw graft copolymer has been predicted.

The novelty addressed here is undertaken by preparing a very efficient cationic flocculant using rice straw waste with different degrees of grafting for the treatment of wastewater using this kind of microwave irradiation approach as an eco-friendly tool. As far as the authors are aware, no thorough investigation has been done in the literature until now dealing with the above-mentioned preparation process.

As a commonly engine coolant, ethylene glycol can produce corrosive acid byproducts at high temperatures when the car is running, specifically oxalic acid (OA), which can shorten the service life of engine. At the same time, chloride ions can also be introduced during coolant preparation processes. Therefore, this paper aims to investigate the synergistic corrosion behavior of Cl⁻ and OA on ADC12 aluminum alloy.

The electrochemical tests, scanning electron microscopy, energy dispersive spectrometer, X-ray diffraction and X-ray photoelectron spectroscopy) were used.

The results showed that the corrosion rate of the aluminum alloy increased with the increase of OA and Cl⁻ concentrations. After adding Cl⁻, the surface film of the aluminum alloy was further damaged, Cl⁻ has a synergistic effect with OA and their interaction further accelerated the corrosion of the aluminum alloy. Nevertheless, as the immersion time increased, the corrosion rate of the aluminum alloy gradually diminished due to the formation of aluminum oxalate.

The corrosion of ADC12 aluminum alloy was studied in OA, Cl⁻ and their mixed solutions; the synergistic effect of OA and Cl⁻ on the corrosion of ADC12 aluminum alloy was discussed, and aluminum oxalate formed inhibited its corrosion.