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The purpose of this paper is to enhance the compatibility of titanium dioxide in epoxy resins and thus the corrosion resistance of the coatings.

In this work, TiO₂ was modified by the mechanochemistry method where mechanical energy was combined with thermal energy to complete the modification. The stability of modified TiO₂ in epoxy was analyzed by sedimentation experiment. The modified TiO₂-epoxy coating was prepared, and the corrosion resistance of the coating was analyzed by open circuit potential, electrochemical impedance spectroscopy and neutral salt spray test.

High-temperature mechanical modification can improve the compatibility of TiO₂ in epoxy resin. At the same time, the modified TiO₂-epoxy coating showed better corrosion resistance. Compared to the unmodified TiO₂-epoxy coating, the coating improved the dry adhesion force by 61.7% and the adhesion drop by 33.3%. After 2,300 h of immersion in 3.5 Wt.% NaCl solution, the coating resistance of the modified TiO₂ coating was enhanced by nearly two orders of magnitude compared to the unmodified coating.

The authors have grafted epoxy molecules onto TiO₂ surfaces using a high-temperature mechanical force modification method. The compatibility of TiO₂ with epoxy resin is enhanced, resulting in improved adhesion of the coating to the substrate and corrosion resistance of the coating.

The purpose of this work was to modify the surface of parawood sawdust (Hevea brasiliensis) microcrystalline cellulose (PW-MCC) used as reinforcing agent in polypropylene composites with benzoyl chloride under a mechanochemistry process.

The acetylated PW-MCC was produced from heterogeneous condition using planetary ball mill process at a rotation speed of 400 rpm. Before the esterification reaction, PW-MCC was pre-treated with pyridine at 60°C for 1 h in order to penetrate and swell the cellulose structure. The optimum condition of esterified PW-MCC with various molar ratios of benzoyl chloride/anhydroglucose unit (AGU) was studied. The degree of substitution, functional group, thermal stability and morphology of esterified cellulose were characterized by ¹H-nuclear magnetic resonance (NMR), Fourier transform infrared spectroscopy (FTIR), thermogravimetric analyzer (TGA) and scanning electron microscopy (SEM).

The functional group from FTIR confirmed that PW-MCC was successfully esterified with benzoyl chloride. The optimum condition which gave the maximum degree of substitution at 3.00 was achieved by using benzoyl chloride/AGU at 5 for 1 h. SEM analysis revealed that the modified PW-MCC surface became rougher than the unmodified PW-MCC surface. The polypropylene composites with 5-30 wt% PW-MCC and esterified PW-MCC were prepared without compatibilizer.

The composites with esterified PW-MCC enhanced water resistance and thermal stability when compared to composites with PW-MCC.

The purpose of this paper is to study the mechanochemical effect and self-growth mechanism of double-network (DN) gel and to provide a quasiperiodic model for rubber elasticity.

The chemical reaction kinetics is used to identify the mechanochemical transition probability of host brittle network and to explore the mechanical behavior of endosymbiont ductile network. A quasiperiodic model is proposed to characterize the cooperative coupling of host–endosymbiont networks using the Penrose tiling of a 2 × 2 matrix. Moreover, a free-energy model is formulated to explore the constitutive stress–strain relationship for the DN gel based on the rubber elasticity theory and Gent model.

In this study, a quasiperiodic graph model has been developed to describe the cooperative interaction between brittle and ductile networks, which undergo the mechanochemical coupling and mechanical stretching behaviors, respectively. The quasiperiodic Penrose tiling determines the mechanochemistry and self-growth effect of DNs.

It is expected to formulate a quasiperiodic graph model of host–guest interaction between two networks to explore the working principle of mechanical and self-growing behavior in DN hydrogels, undergoing complex mechanochemical effect. The effectiveness of the proposed model is verified using both finite element analysis and experimental results of DN gels reported in literature.

This paper aims to explore and demonstrate the ability to integrate entry-level additive manufacturing (AM) techniques with responsive polymers capable of mechanical to chemical energy transduction. This integration signifies the merger of AM and smart materials.

Custom filaments were synthesized comprising covalently incorporated spiropyran moieties. The mechanical activation and chemical response of the spiropyran-containing filaments were demonstrated in materials that were produced via fused filament fabrication techniques.

Custom filaments were successfully produced and printed with complete preservation of the mechanochemical reactivity of the spiropyran units. These smart materials were demonstrated in two key constructs: a center-cracked test specimen and a mechanochromic force sensor. The mechanochromic nature of the filament enables (semi)quantitative assessment of peak loads based on color change, without requiring any external analytical techniques.

This paper describes the first examples of three-dimensional-printed mechanophores, which may be of significant interest to the AM community. The ability to control the chemical response to external mechanical forces, in combination with AM to process the bulk materials, potentiates customizability at the molecular and macroscopic length scales.

In this Chapter, cerium (III) oxide nanoparticles were prepared by co-precipitation method using hydrogen peroxide as the precipitant in slightly alkaline medium which is greener and environmentally suitable, cheap and best as compared to other conventional methods. Here, hydrogen peroxide acts as precipitating, reducing and stabilizing agents. Since studies worldwide reveal a very strong, significant positive association between air pollution and COVID-19 cases, hence, this environment-friendly synthesis process will prove to be most economically effective one to combat the COVID situation. The synthesized cerium (III) oxide nanoparticles were initially noted through visual color change from colorless pale yellow cerium (III) to light yellow cerium (IV). Moreover, the formation and size of cerium (III) oxide nanoparticles were evidenced by the X-ray diffraction, transmission electron microscopy and UV-VIS spectroscopy studies. The very high surface area and very small average crystallite sizes of these prepared cerium (III) oxide nanoparticles (5–20) nm in size is mainly responsible for their catalytic properties and hence can be effectively used for the removal of hazardous toxic pollutant gases such as carbon dioxide and sulfur dioxide from the environment with a view to combat the pollution within the environment to increase sustainability and also ensure a better, healthy and safe environment, particularly, in context of COVID in globalized world. This chapter, as its main objective, mainly focuses on utility of the nanotechnology and its beneficiary in creating a sustainable environment in economic world, particularly for gender development. Since the gas sensors will detect and reduce gaseous toxic pollutants from the environment, so lower the pollution greater will be sustainable environment development in terms of human development index and hence higher will be overall economic development in favor of Gender Development Index across world. However, as major findings, developing countries have been successful in maintaining a sustainable human development, in spite of higher Per Capita Income (PCI) growth, as compared to the role of least developing countries, with lower PCI in this global world, in favor of their respective gender development.

Nanotechnology is nowadays very much successful in producing specifically functionalized nano-sized particles. In this work, copper nanoparticles were prepared by reduction method which is greener and environmentally suitable, cheap and best as compared to other conventional methods, particularly in the context of COVID in globalized world. The formation and size of copper nanoparticles was evidenced by the X-ray diffraction and transmission electron microscopy. The very high surface area of 35–50 m²/gm and very small crystallite sizes of 5–15 nm of these metal nanoparticles is mainly responsible for their effective involvement in removal of carbon dioxide gas as one of major hazardous pollutants from the environment. This chapter, as its main objective, mainly focuses on utility of nano technology and its beneficiary in creating a sustainable environment in economic world. Apart from laboratory experimental procedure and characterizations for preparation of copper nanoparticles, appropriate research methods such as simple statistical, econometric tools and mathematical tools have been used for economic analysis. However, as major findings of the results, developed countries have been successful in maintaining a sustainable human development, in spite of having higher per capita income (PCI) growth as compared to the role of developing countries with lower PCI in this global world.

Revisiting derivations of Gibbs adsorption equation show its applicability to solid surfaces without limiting requirement of constant state of strain. Some attempts to use such a restriction to prove the correctness of the Shuttleworth equation have failed. Also, we have shown that the mandatory conditions for the Maxwell's relations make its inapplicable for the description of capillary and electrocapillary phenomena on solid surfaces, as they lead, if used correctly, to trivial results - known Gibbs adsorbtion equation and Lippmann electrocapillary equation. Attempts to use Maxwell's relations for the case of solid electrodes available in the literature are based on mathematical defects and, consequently, yield erroneous results.

Tribological research is complex and multidisciplinary, with many parameters to consider. As traditional experimentation is time-consuming and expensive due to the complexity of tribological systems, researchers tend to use quantitative and qualitative analysis to monitor critical parameters and material characterization to explain observed dependencies. In this regard, numerical modeling and simulation offers a cost-effective alternative to physical experimentation but must be validated with limited testing. This paper aims to highlight advances in numerical modeling as they relate to the field of tribology.

This study performed an in-depth literature review for the field of modeling and simulation as it relates to tribology. The authors initially looked at the application of foundational studies (e.g. Stribeck) to understand the gaps in the current knowledge set. The authors then evaluated a number of modern developments related to contact mechanics, surface roughness, tribofilm formation and fluid-film layers. In particular, it looked at key fields driving tribology models including nanoparticle research and prosthetics. The study then sought out to understand the future trends in this research field.

The field of tribology, numerical modeling has shown to be a powerful tool, which is both time- and cost-effective when compared to standard bench testing. The characterization of tribological systems of interest fundamentally stems from the lubrication regimes designated in the Stribeck curve. The prediction of tribofilm formation, film thickness variation, fluid properties, asperity contact and surface deformation as well as the continuously changing interactions between such parameters is an essential challenge for proper modeling.

This paper highlights the major numerical modeling achievements in various disciplines and discusses their efficacy, assumptions and limitations in tribology research.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-03-2023-0076/

This work aims to analyze the effect of mechanical activation on structural disordering (amorphization) in an alumina-silica ceramics system and formation of mullite most notably at a lower temperature using X-ray diffraction (XRD). Also, an objective of this work is to focus on a low-temperature fabrication route for the production of mullite powders.

A batch composition of kaolin, alumina and silica was manually pre-milled and then mechanically activated in a ball mill for 30 and 60 min. The activated samples were sintered at 1,150°C for a soaking period of 2 h. Mullite formation was characterized by XRD and scanning electron microscopy (SEM).

It was determined that the mechanical activation increased the quantity of the mullite phase. SEM results revealed that short milling times only helped in mixing of the precursor powders and caused partial agglomeration, while longer milling times, however, resulted in greater agglomeration.

It is noted that, a manual pre-milling of approximately 20 min and a ball milling approach of 60 min milling time can be suggested as the optimum milling time for the temperature decrease succeeded for the production of mullite from the specific stoichiometric batch formed.

The purpose of this paper is to explore the effect of ZnO on the structure and properties of micro-arc oxidation (MAO) coating on rare earth magnesium alloy under large concentration gradient.

The macroscopic and microscopic morphology, thickness, surface roughness, chemical composition and structure of the coating were characterized by different characterization methods. The corrosion resistance of the film was studied by electrochemical and scanning Kelvin probe force microscopy. The results show that the addition of ZnO can significantly improve the compactness and corrosion resistance of the MAO coating, but the high concentration of ZnO will cause microcracks, which will reduce the corrosion resistance to a certain extent.

When the concentration of zinc oxide is 8 g/L, the compactness and corrosion resistance of the coating are the best, and the thickness of the coating is positively correlated with the concentration of ZnO.

Too high concentration of ZnO reduces the performance of MAO coating.

The MAO coating prepared by adding ZnO has good corrosion resistance. Combined with organic coatings, it can be applied in corrosive marine environments, such as ship parts and hulls. To a certain extent, it can reduce the economic loss caused by corrosion.

The effect of ZnO on the corrosion resistance of MAO coating in electrolyte solution was studied systematically, and the conclusion was new to the common knowledge.