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The purpose of this paper is to evaluate the efficiency of acrylated guar gum (AGG) as an additive in alkyd resin for improved mechanical properties and to optimize the results of such an addition.

For studying the effect of AGG on coating properties, guar gum was modified to various degrees of esterification and various compositions of alkyd systems were made by incorporating different concentrations of AGG. The mechanical and solvent absorption of the unmodified and modified alkyd systems were characterized.

The incorporation of AGG into alkyd coating showed significant improvement of mechanical properties over the unmodified one. The modification caused an additional crosslink site through its unsaturation which led to increased crosslink density without phase separation of additive from the alkyd system which was confirmed by SEM scans.

The reactive additive, AGG used in the present study was synthesised using acryloyl chloride. Besides, it could also be synthesised from methacryloyl chloride and the effect of methyl substitution on water and solvent absorption could be studied.

The method developed provided a simple and practical solution to improving the mechanical properties of alkyd coatings.

The method for enhancing mechanical properties of cured alkyd system was novel and could find numerous applications in surface coatings.

Epoxy acrylate which is commercially utilized for UV curable coatings although has excellent adhesion, flexibility, hardness and chemical resistance, they lack in antimicrobial properties. Citric acid (CA) is economical as well as a bio-based compound which possess an antimicrobial activity. So, the purpose of this research investigation is the preparation of CA-based oligomer which can be further incorporated with epoxy acrylate and tri (propylene glycol) Diacrylate (TPGDA) to form uv curable coating and the study of its antimicrobial property.

A UV-curable unsaturated oligomer (CUV) was synthesized from CA and glycidyl methacrylate (GMA). The chemical structure of CUV was confirmed by FTIR, ¹H NMR, GPC, hydroxyl value, acid value and iodine value. Further, CUV was assimilated as an antimicrobial as well as crosslinking agent to copolymerize with epoxy acrylate oligomer and a series of UV-cured antimicrobial coatings were concocted by employing UV-curing machine. The consequence of varying the fraction of CUV on the mechanical, chemical, thermal and antimicrobial properties of UV-cured wood coatings was explored.

Results exhibited good mechanical, chemical and thermal properties. In addition, it was perceived that the zone of inhibition against S. aureus got enlarged with increasing content of CUV in the coating formulation.

The synthesized bio-based CUV reveals an extensive potential to ameliorate the antimicrobial properties of UV-curable coatings.

The purpose of this study is to synthesize structurally different phenalkamines based on cardanol, a renewable material obtained from cashew nut shell liquid, and to evaluate their effect on performance properties of the coatings.

For this purpose, the Mannich reaction between cardanol, formaldehyde and various diamines such as diaminodiphenyl methane (DDM), hexamethylene diamine, Jeffamine D400 and Jeffamine T403 were carried out to produce novel phenalkamines. Resultant phenalkamines were used as curing agents for commercial DGEBPA epoxy resin and were evaluated for performance properties.

The mechanical, optical, chemical, thermal and anticorrosive properties were evaluated and compared with those of commercial phenalkamine AG141. It was observed that anticorrosive properties evaluated using a salt spray test and electrochemical impedance spectroscopy revealed significant improvement in anticorrosive performance of coatings cured with synthesized phenalkamines based on DDM and T403 as compared to the coatings based on commercial phenalkamine AG141.

To obtain optimum performance properties of the coatings, a combination of phenalkamines can be used.

Curing time and gel times of all the phenalkamines can be further studied under wet and humid conditions. In addition, the variation in coating properties under humid conditions can be investigated.

In this study, newer phenalkamines were synthesized and used as curing agents for epoxy coatings. So far, there have been no reports indicating the synthesis and application of phenalkamines based on polyetheramines, namely, Jeffamine D400 and Jeffamine T403, in coating applications.

The purpose of this paper is to explore the application of triglycidyl resin (TGC) prepared from cardanol as partial replacement of conventional bis-phenol A (BPA) based epoxy resin for zinc rich primers (ZRPs).

The synthesis of new platform chemicals that are based on renewable resources has been accepted as a strategy to contribute to sustainable development due to the anticipated depletion of fossil oil reserves and rising oil prices. We prepared a tri-functional epoxy resin from cardanol which can be used as partial replacement of BPA based epoxy. The ZRPs were prepared using 50:50 ratio of TGC:BPA epoxy, and the coatings were evaluated for mechanical, chemical and anticorrosive properties.

The 50 per cent replacement of BPA based epoxy by TGC resulted in at par mechanical, chemical and anticorrosive properties as evaluated by various methods. The successful implementation can thus contribute to sustainable development by “green chemistry” route.

The prepared TGC resin in the current work was studied for application in ZRPs. This can also be explored for high performance coatings, adhesives and other engineering applications.

The TGC binder was prepared by simple two-step reaction. This can successfully be used as binder for coating application without any modifications.

A novel approach of using green and ecofriendly TGC resin as replacement of high cost BPA based epoxy was explored and can be implemented for numerous applications.

The number of people with special needs, including citizens and military personnel, has increased as a result of terrorist attacks and challenging conditions in Iraq and other countries. With almost 80% of the world’s amputees having below-the-knee amputations, Iraq has become a global leader in the population of amputees. Important components found in lower limb prostheses include the socket, pylon (shank), prosthetic foot and connections.

There are two types of prosthetic feet: articulated and nonarticulated. The solid ankle cushion heel foot is the nonarticulated foot that is most frequently used. The goal of this study is to use a composite filament to create a revolutionary prosthetic foot that will last longer, have better dorsiflexion and be more stable and comfortable for the user. The current study, in addition to pure polylactic acid (PLA) filament, 3D prints test items using a variety of composite filaments, such as PLA/wood, PLA/carbon fiber and PLA/marble, to accomplish this goal. The experimental step entails mechanical testing of the samples, which includes tensile testing and hardness evaluation, and material characterization by scanning electron microscopy-energy dispersive spectrometer analysis. The study also presents a novel design for the nonarticulated foot that was produced with SOLIDWORKS and put through ANSYS analysis. Three types of feet are produced using PLA, PLA/marble and carbon-covered PLA/marble materials. Furthermore, the manufactured prosthetic foot undergoes testing for dorsiflexion and fatigue.

The findings reveal that the newly designed prosthetic foot using carbon fiber-covered PLA/marble material surpasses the PLA and PLA/marble foot in terms of performance, cost-effectiveness and weight.

To the best of the author’s knowledge, this is the first study to use composite filaments not previously used, such as PLA/wood, PLA/carbon fiber and PLA/marble, to design and produce a new prosthetic foot with a longer lifespan, improved dorsiflexion, greater stability and enhanced comfort for the patient. Beside the experimental work, a numerical technique specifically the finite element method, is used to assess the mechanical behavior of the newly designed foot structure.

In this study, solid formaldehyde, benzoguanamine and butanol were used to synthesize butylated benzo-amino resin by one-step-two-stage method.

This research first examined the influence of solid formaldehyde content on the hydroxymethylation phase. Subsequently, the effects of butanol content, etherification time and hydrochloric acid content on the formation of benzo-amino resin during the etherification stage were studied in detail. In addition, the reaction process was further analyzed through interval sampling withdrawing during the hydroxymethylation and etherification stages. Finally, the synthesized benzo-amino resins were used in the production of high solid content polyester and acrylic coatings and the properties of that were also evaluated.

Based on the experimental findings, the authors have successfully determined the optimal process conditions for the one-step-two-stage method in this study. The hydroxymethylation stage demonstrated the most favorable outcomes at a reaction temperature of 60°C and a pH of 8.5. Similarly, for the etherification stage, the optimal conditions were achieved at a temperature of 45°C and a pH of 4.5. Furthermore, the investigation revealed that a ratio of benzoguanamine to solid formaldehyde to n-butanol, specifically at 1:5.2:15, produced the best results. The performance of the resulting etherified benzo-amino resin was thoroughly evaluated in high solid content coatings, and it exhibited promising characteristics. Notably, there was a significant enhancement in the water resistance, solvent resistance and glossiness of canned iron printing varnish coatings.

Amino resin, a versatile chemical compound widely used in various industries, presents challenges in terms of sustainability and operational efficiency when synthesized using conventional methods, primarily relying on a 37% formaldehyde solution. To address these challenges, the authors propose a novel approach in this study that combines the advantages of the solid formaldehyde with a two-stage catalytic one-step synthesis process. The primary objective of this research is to minimize the environmental impact associated with amino resin synthesis, optimize resource utilization and enhance the economic feasibility for its industrial implementation. By adopting this alternative approach, the authors aim to contribute toward a more sustainable and efficient production of amino resin.

To study the effect of addition of free diols and triols in the coating formulation on coating properties.

Polyester resins were synthesised from maleic anhydride, dimerised fatty acid, neopentyl glycol and tris (2‐hydroxyethyl) isocyanurate (THEIC). Then, ethylene glycol, propylene glycol, glycerol, trimethylol propane and THEIC were added as reactive components to the coating formulation. These coatings were then analysed for various coating properties and compared with those obtained with the base resins.

The coatings obtained with the addition of these reactive components were found to have improved properties compared with those of the base resins except in cases where the reactive component itself contributed to a reduction in performance, e.g. reduced alkali resistance with the addition of THEIC.

The addition of the free diols and triols required a corresponding increase in the amount of the curing agent to be added.

This process would allow for the tailoring of coatings to suit requirements to a certain extent without modifying the base resin. The addition of low molecular weight components in the coating formulation, which is then incorporated in coatings, could reduce the solvent requirement.

Although polyesters are an established polymeric system in coatings, the use of reactive diluents has not been investigated with the exception of unsaturated polyesters, whose curing chemistry is fundamentally different from that of polyesters focused on in this paper.

The purpose of this paper is to investigate the correlation between the dynamic behavior of a full‐scale steel prototype and a small‐scale plastic model fabricated using fused deposition modeling (FDM).

Based on the use of a known input excitation, the small‐scale model is tested on a shake‐table. Experimental results are compared with results of a full prototype study and with computational models in an effort to assess the feasibility of testing small‐scale FDM models.

Time History Records present strong correlation with prototype data and are reproducible using computational methods. Matching the first natural frequency of the studied structure proved to be a large part of achieving the desired response.

Including the direct measurement of floor displacements will potentially highlight different aspects of model behavior not observed by recording accelerations only. Further investigation into the damping properties of acrylonitrile butadiene styrene plastic is recommended towards further understanding the model response.

Although this paper is based on a simple structure, the benefits of layered manufacturing (LM) methods include speed and ease of generating geometrically complex solids. The implications of the success of this pilot study include the ease in which the dynamic response of complex structures can be assessed using small‐scale LM models.

This project obtained baseline information on the dynamic behavior of FDM plastic parts. It provides assessment of the value of using small‐scale LM models to accurately predict the dynamic response of structures subjected to earthquake excitation.

This paper considers a series system consisting of n different components having unknown and variable failure rates, where the lifetime of components follow exponential distribution having non-constant failure rates. Moreover, the failure rates are bounded by above and are dependent on environmental factors such as temperature, pressure, through linear relationship. The purpose of this paper is to design a component reliability test plan for such a series system with an unknown variable failure rate.

The reliability of the system is estimated with the help of the unbiased estimator of failure rate. The testing procedure is stopped when a fixed number of failures occur for each component.

An optimal reliability test plan is designed and the resultant non-linear integer optimization problem is formulated satisfying the constraints of producer’s and consumer’s risks. The obtained results are compared with the results available in the literature. Some examples are considered to illustrate the approach.

It is observed that use of prior information in the form of an upper bound and incorporation of environmental factors have the advantage of savings in the total testing cost.

The purpose of this paper is to investigate the corrosion resistance of SiO₂-Al₂O₃ coating on mild steel.

SiO₂-Al₂O₃ was coated using sol-gel method, and electrochemical measurements were applied to assess the performance of the coated steel.

The main conclusion is that SiO₂-Al₂O₃-coated specimens acquired a higher corrosion resistance than that of uncoated specimen. i_corr values of the coated specimens were between 12 and 14 times smaller than those of uncoated specimen. The coated specimens exhibited a higher R_cor value at electrochemical impedance spectroscopy analysis. The high values of R_cor and low values of CPE_dl observed within the SiO₂-Al₂O₃-coated samples imply an improved anti-corrosion capability.

In this work, there are three points of originality. First, steel specimens were coated with ormosil-based solution by applying sol-gel dip coating method. Second, both SiO₂ and Al₂O₃ coatings were applied simultaneously at a considerably low temperature, i.e. 200 °C. Finally, the performance of the coated materials against wet corrosion was improved significantly.