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One of the low-cost minerals that can be used as reinforcing filler in polymer industry is pumice powder. Pumice is a highly porous volcanic glass formed during explosive eruptions. This pumice has received significant interest because of its large surface area with various polar groups and can be processed easily.

This study is carried out to investigate the effect of partial replacement of silica (as traditional filler) by naturally occurring pumice powder to improve the thermal and mechanical properties of nitrile butadiene rubber cured with electron beam radiation (doses from 25 to 150 kGy).

The results indicated that the addition of pumice powder increase the tensile strength at lower doses up to 75 kGy (especially at concentration of 5 phr). Besides, an improvement in the thermal stability was attained with the addition of pumice powder.

Pumice powder is volcanic-based alumina and silica which is mainly composed of SiO₂. It has porous structure which is formed by dissolved gases precipitated during the cooling as the lava hurtles through air. Due to its porous structure, it has low density and high thermal insulation. It also has high temperature and chemical resistance, for these reasons it became preferable material to be used as filler in the plastic and rubber industry.

This study aims to prepare activated carbon (AC) and activated biochar (BC) from sugarcane bagasse (SCB) can be used as carbon black (CB) replacement for styrene butadiene rubber (SBR) composites cured by electron beam (EB) radiation.

This study is carried out to investigate the effect of partial replacement of CB (as traditional filler) by AC or BC prepared from low-cost agricultural wastes (SCB) to improve the properties of SBR rubber cured by EB radiation (doses from 25 to 150 kGy).

The results indicated that the addition of AC or BC leads to improve the physical and mechanical properties of SBR with increasing irradiation dose [especially at concentration of 10 parts per hundred part of rubber (phr) from BC]. Also in this study, this paper examines how exposure of SBR rubber composites to ultraviolet (UV) radiation changes the mechanical properties for these composites, to do that, the specimens were examined before and after they were exposed to UV radiation for 300 h. The results showed that, the irradiated SBR composites, UV exposure, exhibit better retention in mechanical properties as compared with unirradiated ones, and the samples loaded with CB hybrid with ACs had an increased value of tensile strength (TS) retention as compared with blank sample.

The importance of this study is that, the production of AC from SCB offers a huge opportunity to overcome the problem of the disposal of SCB.

This study aims to investigate the influences of polyester fabric layers on the mechanical properties of SBR and devulcanized waste rubber composite materials, as well as the effect of gamma irradiation dose.

The devulcanized waste rubbers (DWR) were carried out by different methods. First, chemically, by two different reclaiming agents such as tetramethylthiuram disulfide (TMTD) and 2-mercapto benzothiazole disulfide (MBTS). Secondary by a physical method like microwave (MW). The devulcanized rubbers were mixed with virgin styrene butadiene rubber (SBR) in different ratios, as follows: SBR-DWR (TMTD) 50 / 50, SBR-DWR (MBTS) 80 / 20 and SBR-DWR (MW) 80 / 20. A series of sandwich polyester tire cord fabrics were used as reinforcement for making SBR and devulcanized waste rubber composite materials and molded on a hot press into rubber sheet films, then subjected to gamma radiation at different doses ranging from 100 up to 200 kGy.

The experimental results indicate that increasing the layer number improves the mechanical properties of composites. The tensile strength, tearing, hardness and elastic modulus of the rubber composites increased with the rise of the fiber layers and by increasing the irradiation dose up to 200 kGy. The reclaiming agent TMTD gave the best results for mechanical properties, followed by MW and then MBTS.

This phenomenon can be detailed based on the fact that when the fiber-reinforced composites are subjected to loading, the fibers act as load carriers, depending on the population and orientation of the fibers. Also, scanning electron microscopy (SEM) reveals that adhesion was caused by tire cord fabrics and rubber blend matrix.

The purpose of this paper is to study electrochemically and by weight loss experiments the effect of P,P′‐Bis (triphenylphosphonio) methyl benzophenone dibromide (TPPMB) on the corrosion inhibition of mild steel in 1.0M HCl solution, which will serve researchers in the field of corrosion.

Weight loss measurements were carried out on mild steel specimens in 1.0M HCl and in 1.0M HCl containing various concentrations (2×10⁻⁸M and 2×10⁻⁵M) of the laboratory synthesized TPPMB at temperatures ranging from 303 to 343 K.

TPPMB was found to be a highly efficient inhibitor for mild steel in 1.0M HCl solution, reaching about 98% at the concentration of 2×10⁻⁵M at 303 K, a concentration and temperature considered to be very moderate. The percentage of inhibition in the presence of this inhibitor was decreased with temperature which indicates that physical adsorption was the predominant inhibition mechanism because the quantity of adsorbed inhibitor decreases with increasing temperature.

This inhibitor could have application in industries, where hydrochloric acid solutions at elevated temperatures are used to remove scale and salts from steel surfaces, such as acid cleaning of tankage and pipeline, and may render dismantling unnecessary.

This paper is intended to be added to the family of phosphonium salt corrosion inhibitors which are highly efficient and can be employed in the area of corrosion prevention and control.

This paper aims to investigate the corrosion inhibition effects of indole-3-carbaldehyde and 2-methylindole on mild steel in 1 M HCl solution.

Indole-3-carbaldehyde and 2-methylindole as corrosion inhibitors of mild steel in 1 M HCl solution were investigated by polarisation and electrochemical impedance spectroscopy (EIS). Adsorption isotherm and mechanism were calculated. Quantum chemical calculations were used to find out a correlation between electronic structure of inhibitors and inhibition efficiency. Changes in the properties of metal surface in HCl solution in the presence of inhibitors were studied by contact angle measurements.

Polarisation results revealed inhibitors could reduce cathodic and anodic reactions rates on metal surface. EIS analysis showed that inhibition efficiency of indoles increases by increasing the inhibitors’ concentration; maximum inhibition efficiency was 95 and 94 per cent in solutions containing 1 mM indole-3-carbaldehyde and 2-methylindole, respectively. Inhibitors’ adsorptions on metal surface were confirmed by analysing the exposed metals’ surface through contact angles measurements. The adsorption of inhibitors was found to follow Langmuir isotherm. Quantum chemical calculations showed that a more positively charged benzene ring in the structure of two indole-based inhibitors would lead to higher adsorption to metal.

This research was carried out to understand the effects of two different functional groups (-C=O, -CH3) with different induction effects on the indole structure and on inhibition efficiency of corrosion inhibitors with the purpose of using these components in industrial application as acid wash solutions to etch and remove rusts from metal surfaces.

The purpose of this study is to inspect the corrosion inhibition of API N80 steel pipelines in uninhibited solution and inhibited with a synthesized surfactant compound [N-(3-(dimethyl octyl ammonio) propyl) palmitamide bromide] (DMDPP), which is prepared through a simple and applicable method.

Weight loss was inspected at five different temperatures of 25°C, 30°C, 40°C, 50°C and 60°C Potentiodynamic polarization, electrochemical impedance spectroscopy (EIS) and electrochemical frequency modulation were used at room temperature. Density functional theory was used to study the relation between the molecular structure and inhibition theoretically.

Adsorption of the prepared DMDPP fits the Langmuir isotherm model. The inhibition efficiency of the prepared DMDPP amphipathic inhibitor is directly proportional to temperature increase. Polarization results reveal that the investigated DMDPP amphipathic compound behaves as a mixed-type inhibitor. EIS spectra produced one individual capacitive loop.

The originality is the preparation of cationic surfactants through a simple method, which can be used as corrosion inhibitors in oil production. The synthesized inhibitors were prepared from low-price materials. The work studied the behavior of the synthesized surfactants in inhibiting the corrosion of the steel in an acidic medium. Electrochemical and theoretical studies were presented, besides gravimetric and surface examination.

This paper aims to study the corrosion inhibition of Methyl 2-(benzamido)-2-(4-phenyl-1H-1,2,3-triazol-1-yl) acetate (MBPTA) and Methyl 2-(benzamido)-2-(4-p-tolyl-1H-1,2,3-triazol-1-yl) acetate (MBTTA) in 1 M H2SO4 solution at 25 °C.

The authors have used weight loss measurements, electrochemical impedance spectroscopy (EIS), potentiodynamic polarization, FT-IR, quantum chemical calculations and scanning electron microscopy (SEM) techniques.

The polarization measurements indicate that both compounds are mixed type inhibitors, and that MBTTA is more effective than MBPTA. The effect of temperature on the corrosion behavior using optimal concentration of MBTTA and MBPTA was studied in the temperature range 298-328 K. SEM was used to examine the morphology of the metal surface. Thermodynamic parameters were calculated and discussed. Monte Carlo simulations were applied to lookup for the most stalls configuration and adsorption energy for the interaction of inhibitors on Fe (1 1 1) interface. The difference in inhibition efficiencies between the two organic inhibitors can be clearly explained in terms of frontier molecular orbital theory.

The authors report on the comparative inhibiting effect of two new 1,4-disubstituted 1,2,3-triazoles, namely Methyl 2-(benzamido)-2-(4-phenyl-1H-1,2,3-triazol-1-yl) acetate (MBPTA) and Methyl 2-(benzamido)-2-(4-p-tolyl-1H-1, 2, 3-triazol-1-yl) acetate (MBTTA) on mild steel corrosion in 1 M H₂SO₄ solution.

This study aims to examine the metal pollution in coastal sediment in the Peninsular Malaysia.

Approximately 141 published studies were screened from 1,285 documents and reviewed to determine the existing pollution status in the coastal areas of Peninsular Malaysia and the metals under review were Pb, Hg, Cd, Ar, Cu, Zn, Cr and Ni. Sources of pollutants and their effect on biological systems, marine organisms and human health were addressed in this review as well as recommendation of heavy metal removal or remedies in short. Emphasis is placed on marine pollution, particularly on the toxic metal accumulation in biota.

This study has revealed the different concentrations of pollutants, low, moderately, and chronically contaminated areas from heavy metals and the consequences to aquatic ecosystem and indirectly to human health, since an increasing in the coastal developments in Peninsular Malaysia.

This study has revealed the different concentrations of pollutants, low, moderately, and chronically contaminated areas from heavy metals and the consequences to aquatic ecosystem and indirectly to human health, since an increasing in the coastal developments in Peninsular Malaysia.