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The objective of the present work was to study the influence of chemical compositions of five naphthenic acids (NAs) extracted from Liaohe crude oil on their corrosivity.

Fourier‐transform infrared spectrometry and electron impact mass spectrometry were used to characterize the chemical structures and compositions if five NAs. The corrosivities of the NAs were assessed by stagnant NA corrosion (NAC) tests. An attempt was made to identify any correlation between the chemical composition of the NAs and their corrosiveness.

The acidic species in all five NA samples were saturated aliphatic and naphthenic acids and the amount of aromatic and unsaturated acids was negligible. A relationship between the carboxylic acid distribution and the molecular weight was obtained. Most of the carboxylic acids in five NAs contained 0‐3 ring structures. NAs with lower molecular weight and fewer ring structures usually were more corrosive.

The findings have important implications for assessing the corrosivity of acidic crude oils from various resources.

This paper seeks to study the corrosion rate (CR) of Al 6063 in aqueous solutions containing food additives, namely ascorbic, citric and tartaric acids with/without chloride ions.

Chemical and electrochemical measurements were used to study the CR of Al 6063 in aerated aqueous solutions. Chemical measurements include weight loss (WL) and atomic absorption (AA). The surface morphology of Al 6063 was studied using scanning electron microscope connected with energy dispersion X‐Ray (EDX). Electrochemical measurements were made using a potentiostat/galvanostat; the effect of pH, temperature and immersion time was studied.

AA gave comparable results to that of WL. EDX results showed the depletion of Mg and Fe from the Al 6063 to carboxylic acid solutions w/without NaCl. From electrochemical measurements, it was found that addition of chloride ions to carboxylic acids increased the CR of Al 6063 especially at low pH and high temperatures but it reduced the CR at long immersion times.

Aluminum (Al) is now known to be a neurotoxin agent yet Al cook wares are widely used in different countries. The acids used in this study are food additives which implies that the Al cook wares may corrode in food containing these acids and other carboxylic acids depending on pH, temperature and the presence of other additives.

AA gave comparable results to that of WL, which shows that it may be used to evaluate leaching metal ions in μg levels or less in corrosion measurements.

The purpose of this paper is to investigate in detail the effects of acid treatment on multi‐walled carbon nanotubes (MWNTs), which could find a variety of applications in coatings and composites.

A number of analytical techniques, including Fourier transform infrared spectroscopy (FT‐IR), X‐ray photoelectron spectroscopy (XPS), Raman spectroscopy (Raman), and scanning electron microscopy (SEM), were employed to assess the effects of acid treatment on MWNTs.

It was found that desirable modifications to MWNTs occurred after acid treatment. Thus, carboxylic acid groups were introducing on to the surface of MWNTs. It was also found that both chemical and physical properties of MWNTs could be modified/altered.

The investigation established a method to modify MWNTs via acid treatment and the effects of such a treatment on MWNTs in detail. The modified MWNTs can be used for various applications and further modifications. The acid treated and the further modified MWNTs can be dispersed into polymers to prepare polymer/MWNTs composite materials and composite surface coatings. Some properties of the resulting composites were improved by the dispersed MWNTs, giving excellent mechanical, electrical, thermal and magnetic properties.

The finding on the effects of acid treatment on MWNTs, supported by detailed FT‐IR, XPS, Raman and SEM data, would be of interest to the field. The modification technique provided a route to further modification of carbon nanotubes. The acid treated and the further modified MWNTs are useful for preparation of polymer/MWNTs composite materials and composites surface coatings with improved mechanical, electrical, thermal and magnetic properties.

The purpose of this paper is to investigate the effects of multi‐walled carbon nanotubes (MWNTs) on the mechanical, thermal and electrical conductivity properties of polyurethane (PU) by in situ polymerisation of MWNTs and PU.

A number of analytical techniques, including Fourier transform infrared spectroscopy and X‐ray photoelectron spectroscopy, were employed to assess the effects of acid treatment on MWNTs. The mechanical and thermal properties of PU, MWNTs and PU composites were characterised using a tensile tester machine and dynamic mechanical analysis. The electoral conductivity properties of the materials were characterised by ohmmeter.

It was found that desirable modifications to MWNTs occurred after acid treatment, thus mainly carboxylic acid groups were introduced onto the surface of MWNTs. And the acid‐treated MWNTs could improve the mechanical, thermal and electrical conductivity properties of PU by in situ polymerisation of MWNTs and PU successfully.

The investigation established a method to synthesise MWNTs and PU composites by in situ polymerisation. The mechanical, thermal and electrical conductivity properties of PU could be improved by the inclusion of MWNTs.

The paper establishes a method to synthesise MWNTs and PU composites by in situ polymerisation; and the effects of MWNTs on modifying mechanical, thermal and electrical conductivity properties of PU by in situ polymerisation are investigated in detail.

Valuable information on the corrosion of drilling, turning, milling and grinding machine surfaces by soluble cutting oils was brought to light by tests carried out by the Production Engineering Research Association. Eleven soluble oils were analysed and subjected to a simple test, described in this article, which users of such oils can carry out for themselves. The eleven oils varied considerably in their corrosive effects, pointing the need for careful selection. The way in which the oils have been mixed; whether metal chips have been left on the machine tool surfaces; whether the surfaces have been greased; these and other factors have an important bearing on the corrosive effect of soluble oils. In this article, the tests carried out by the P.E.R.A. are described and the data obtained, together with the conclusions and recommendations of the investigators, are presented.

The purpose of this paper is to investigate the effects of carbon nanotubes (CNTs) on the mechanical, thermal and colour properties of solvent-containing two-component polyurethane (PU) coating.

Fourier transform infrared spectroscopy and observation of dispersion stability were used to assess the effects of acid treatment on CNTs. The CNTs and PU composite coating was synthesised by in situ polymerisation and bending polymerisation, and the mechanical, thermal and colour appearance properties of coating were characterised.

It was found that desirable modifications to CNTs occurred after acid treatment; thus, mainly carboxylic acid groups were introduced onto the surface of CNTs. And the acid-treated CNTs could improve the mechanical and thermal properties of PU coating, and the properties of composite coating was improved more successfully by in situ polymerisation than by blending polymerisation.

The investigation established a method to synthesise CNTs and PU composite coating. The mechanical and thermal properties of PU coating could be improved by the inclusion of CNTs.

This study established a method to synthesise CNTs and PU composite coating by in situ polymerisation and blending polymerisation; the effects of CNTs on modifying mechanical, thermal and colour properties of PU coating were investigated and compared in detail.

The purpose of this paper is to prepare poly[allyl amino bis(methylene phosphonic acid)-ran-acrylic acid]s by two different routes. In the first route, poly(allyl amine-ran-acrylic acid)s were produced by radical copolymerization of a mixture of ally amine and acrylic acid, then converted into poly[allyl amino bis(methylene phosphonic acid)-ran-acrylic acid]s by the Mannich reaction with a mixture of formaldehyde and phosphonic acid. In the second route, allyl amino bis(methylene phosphonic acid) monomer was synthesized and copolymerised with acrylic acid. The aim of this work is to produce low-molecular-weight copolymer with the low amount of nitrogen and phosphorous having better scale inhibiting performance than commercial low-molecular-weight poly(acrylic acid)s.

Poly(allyl amine-ran-acrylic acid)s were prepared by radical copolymerisation of a mixture of ally amine and acrylic acid, and the molecular weight of copolymers was regulated by using an effective chain transfer compound and the formed copolymer was reacted with a mixture of formaldehyde and phosphorous acid. Allyl amino bis(methylene phosphonic acid) monomer was prepared and then copolymerised with acrylic acid using radical initiators.

Poly[allyl amino bis(methylene phosphonic acid)-ran-acrylic acid] produced with both routes, especially low-molecular weight ones have better anti-scaling performance than low-molecular-weight commercial poly(acrylic acid).

By using an excess of formaldehyde and phosphonic acid, a limited increase in the conversion of amine groups of poly(allyl amine-ran-acrylic acid) to amino methylene phosphonic acid groups was achieved, so unreacted amine groups were always present in the structure of the final copolymers.

The low-molecular-weight poly[allyl amino bis(methylene phosphonic acid)-ran-acrylic acid] may be used as a better anti-scaling polymer in industry.

The low-molecular-weight poly[allyl amino bis(methylene phosphonic acid)-ran-acrylic acid] is an alternative polymer for scale inhibition in the water boilers.

The low-molecular-weight poly[allyl amino bis(methylene phosphonic acid)-ran-acrylic acid] copolymers containing both carboxylic acid and amino bis(methylene phosphonic acid) are more effective anti-scaling additives than poly(acrylic acid)s in water boilers.

This paper aims to prepare highly hydrophobic films on aluminum AA3003 using myristic acid (MA) and evaluate its corrosion protection efficiency in a low-chloride solution.

The aluminum surface was initially treated with boiling water to develop a porous nanostructure, and then surface modification was carried out in ethanolic solutions with different concentrations of MA. The surface morphology, wetting behavior and film composition were first characterized, and then, the corrosion behavior was evaluated with electrochemical techniques.

The best hydrophobicity and corrosion resistance were obtained with 50 mM of MA. For such concentration, a water contact angle of 140° and protective efficiency of 96% were achieved. A multilayer structure was revealed by scanning electron microscope and X-ray photoelectron spectroscopy.

The results of this work shed light on the anticorrosion performance of fatty acid self-assembled multilayers on the surface of Al–Mn alloys.

This study aims to characterize the composition of the tribo-layer formed during sliding of steel in the presence of crude jatropha oil (CJO) and epoxidized jatropha oil (EJO) under boundary lubricant application.

CJO was obtained from a local market and used as received. EJO was obtained by epoxidation process with peroxyformic acid catalyzed by acidic ion exchange resin. The tribological test was conducted by the four ball method according to ASTM 4192. Wear scars generated on the lower balls were used to characterize the tribo-layer. Energy-dispersive X-ray and X-ray photo spectroscopy analysis were conducted to characterize the tribo-layer composition.

EJO shows a lower friction coefficient compared to CJO. Moreover, EJO also shows better wear preventive properties compared to CJO. The oxidation of CJO and EJO has lead chemisorption of the oil to steel surface to cause formation of protective layers for the steel surface. The layers were constructed from inorganic oxide in the form of iron oxides and silicon oxide together with organic layers in form of aldehyde, ketone and carboxylic acid. The formation and removal of this layer from rubbing sites are considered to affect wear-preventive and friction behaviour of steel lubricated with CJO and EJO.

This works highlights friction and anti-wear characteristics of CJO and EJO. This work also presents the composition of the tribo-layer that formed because of the sliding of steel lubricated with CJO and EJO. The method and result can be used for further investigation and development of lubricant.

The purpose of this paper is to provide a critical and in‐depth review of the present status and recent developments in synthetic methodologies, reaction engineering, process design and quality control aspects associated with the manufacture of mono and multifunctional acrylate monomers.

This paper reviews commercially important UV cure mono and multifunctional acrylate monomers. It covers their synthesis, catalyst, and appropriate solvents for azeotropic removal of byproducts. The detail discussion on catalysis, basis of design of reactors and commercial plant and the process engineering associated with the manufacture has been supported through citation of synthesis of various acrylate monomers. The methodologies adopted for determination of physical, chemical and compositional characterisation of acrylate monomers have been presented. In addition, the guidelines regarding the bulk storage and commercial handling of acrylates have been reviewed.

The reaction engineering of esterification reaction between acrylic acid and polyol has been worked out to provide the basis for selection of reactors. The reaction has been modeled as a series – parallel complex reaction for providing explanation for generation of various byproducts/adducts and multiple esters.

The detailed discussion on formation, characterisation and treatment of Michael adducts and purification of acrylate monomers will be relevant for new researchers for further development. A review of guidelines on selection of homogenous and heterogeneous catalysts for synthesis of acrylate monomers has been presented.

Since the related literature on acrylate monomers is scarce, scattered and proprietary, the consolidated coverage in one paper will be useful.