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Fabrication and Characterization of SnO-Cu₂O Mixed Metal Oxide Thin Films for Photoelectrochemical Applications

Ahmed S, Shahid MM, Bakar SA, Arshed N, Basirun WJ, Fouad H

J Nanosci Nanotechnol, 2020 12 01;20(12):7705-7709.
PMID: 32711646 DOI: 10.1166/jnn.2020.18570

Herein, we report the synthesis of SnO, Cu₂O and SnO-Cu₂O mixed oxide thin films on fluorinedoped tin oxide (FTO) substrate by Aerosol-Assisted Chemical Vapour Deposition (AACVD) process using [Cu (dmae)₂(H₂O)] and [Sn (dmae) (OAc)]₂ as molecular precursors for SnO and Cu₂O, respectively at 400 °C. The X-ray diffraction (XRD) pattern can be ascribed to the tetragonal phase of SnO crystals with space group P4 and cubic phase of Cu₂O crystals with space group Pn- 3m/nmm, respectively. The surface morphology characteristics of SnO, Cu₂O and SnO-Cu₂Omixed oxide have been investigated using Field Emission Scanning Electron Microscope (FESEM) which revealed that the SnO was grown homogeneously in cubical shape while Cu₂O possess nano balls shaped morphologies. The UV band gap values of SnO-Cu₂O mixed oxide thin film was found to be 2.6 eV appropriate for photoelectrochemical (PEC) applications. The synthesized material was proposed for PEC applications and has shown enhanced catalytic performance in the presence of light.

Matched MeSH terms: Copper
Fulltext Biosynthesis of nanoparticles using recombinant bromelain

Arina Nasruddin, Azura Amid, Muhd Ezza Faiez Othman

Biological and Natural Resources Engineering Journal, 2018;1(1):14-25.
MyJurnal

Green chemical method was applied to synthesize nanoparticles using recombinant
bromelain. Among the numerous applications of recombinant bromelain, there is still no research
on nanoparticles synthesis which encourages its utilization in this study. Four chemicals which are
copper (II) chloride dihydrate (CuCl2.2H2O), cerium nitrate hexahydrate (Ce(NO3)3.6H2O), sodium
selenite (Na2SeO3), and iron (III) chloride hexahydrate (FeCl3.6H2O) were selected to be screened
for the suitability in nanoparticles biosynthesis by recombinant bromelain. The nanoparticles
formed were characterized by using UV-visible absorption spectra. The biosynthesis process then
was optimized by varying the centrifugation speed, temperature, and time to get the maximum
absorption and weight of nanoparticles through central composite design (CCD) tool. Only
CuCl2.2H2O showed a positive result for the screening process which was represented by the
formation of colloidal solution and a maximum absorption at 580 nm. Thus, optimization was
carried out for this chemical. Based on the optimization model, maximum absorption and weight
were predicted at 67.5°C, 2 hrs, and 9,600 rpm. These optimal conditions were validated by
repeating the biosynthesis process. The absorption and weight of the nanoparticles depended on the
reaction of the chemical with recombinant bromelain. 3D plots showed that the optimal condition
for high responses mostly depends on temperature and time.

Matched MeSH terms: Copper
Fulltext Investigation of Heat Transfer and Pressure Drop in Microchannel Heat Sink Using Al2O3 and ZrO2 Nanofluids

Khan MZU, Uddin E, Akbar B, Akram N, Naqvi AA, Sajid M, et al.

Nanomaterials (Basel), 2020 Sep 09;10(9).
PMID: 32916991 DOI: 10.3390/nano10091796

A new micro heat exchanger was analyzed using numerical formulation of conjugate heat transfer for single-phase fluid flow across copper microchannels. The flow across bent channels harnesses asymmetric laminar flow and dean vortices phenomena for heat transfer enhancement. The single-channel analysis was performed to select the bent channel aspect ratio by varying width and height between 35-300 μm for Reynolds number and base temperature magnitude range of 100-1000 and 320-370 K, respectively. The bent channel results demonstrate dean vortices phenomenon at the bend for Reynolds number of 500 and above. Thermal performance factor analysis shows an increase of 18% in comparison to straight channels of 200 μm width and height. Alumina nanoparticles at 1% and 3% concentration enhance the Nusselt number by an average of 10.4% and 23.7%, respectively, whereas zirconia enhances Nusselt number by 16% and 33.9% for same concentrations. On the other hand, thermal performance factor analysis shows a significant increase in pressure drop at high Reynolds number with 3% particle concentration. Using zirconia for nanofluid, Nusselt number of the bent multi-channel model is improved by an average of 18% for a 3% particle concentration as compared to bent channel with deionized water.

Matched MeSH terms: Copper
Fulltext Chitosan Epoxidized Natural Rubber Biocomposites for Sorption and Biodegradability Studies

Raju G, Mas Haris MRH, Azura AR, Ahmed Mohamed Eid AM

ACS Omega, 2020 Nov 10;5(44):28760-28766.
PMID: 33195929 DOI: 10.1021/acsomega.0c04081

The slow-release mechanism of copper into soil followed by soil biodegradation was studied using the chitosan (CTS)/epoxidized natural rubber (ENR) biocomposite. The biocomposite was prepared by homogenizing CTS in ENR50 (ENR with about 50% epoxy content) latex in the presence of curing agents and acetic acid. It was found that the adsorption property of the biocomposite was very much influenced by chitosan loading, where 20phrCTS-t-ENR biocomposite can absorb 76.31% of Cu(II) ions. The desorption study indicates that the copper (II) ion can be released at a very slow and control phase as proven by the kinetic study using zero-order, first-order, Higuchi, and Korsmeyer Peppas equations. The slow-release studies comply with the Higuchi square-root equation, indicating that the release process is diffusion-controlled. Results of desorption and biodegradation process suggest that this biocomposite has the potential use of being a slow-release matrix in the field of agriculture.

Matched MeSH terms: Copper
Fulltext Design of a Smart Safety Vest Incorporated With Metal Detector Kits for Enhanced Personal Protection

Rajendran SD, Wahab SN, Yeap SP

Saf Health Work, 2020 Dec;11(4):537-542.
PMID: 33329921 DOI: 10.1016/j.shaw.2020.06.007

Background: Personal protective equipment (PPE) has been designed in such a way to reduce accident rates. Unfortunately, existing PPE is rather ineffective as it is not able to provide warning signals when hazard is around. The integration of intelligent systems is envisaged to increase the efficiency of existing PPE.
Methods: This project designed a safety vest incorporated with metal detectors which can provide immediate warning to the field workers when there is metal hazard around. This product has greater freedom of design via smart manufacturing as it involves the assembly of few commercially available parts into a single entity. Briefly, the metal detector is a do it yourself (DIY) kit, and the safety vest is purchasable from any local market. The DIY kit was connected to a copper coil and being sewed into the safety vest.
Results: The metal detector induces beeping sound when there is metal hazard around. A total of 121 engineering students were introduced to the prototype before being requested to answer a survey associated with the design. Respondents have rated >3.00/5.00 for the design simplicity, ease of usage, and light weight. Meanwhile, respondents suggested that the design should be further improved by increasing the metal detection range.
Conclusion: It is envisaged that the introduction of this smart safety vest will allow the workers to carry out their duties securely by reducing the accident rates. Particularly, such design is expected to reduce workplace accident especially during night time at construction sites where the visibility is low.

Matched MeSH terms: Copper
Interaction of Aqueous Solutions of a Surface Active Copper(II) Complex with Several Common Surfactants

Lim YY, Lim KH

J Colloid Interface Sci, 1997 Dec 01;196(1):116-9.
PMID: 9441659

Micellar properties of binary mixed surfactants of a surface active mixed copper(II) chelate, [Cu(C12-tmed)(acac)Cl] (where C12-tmed is N,N,N'-trimethyl-N'-dodecylethylenediamine) with three common surfactants, viz. sodium dodecyl sulfate (SDS), cetyltrimethylammonium bromide (CTAB), and octaethylene glycol monododecyl ether (C12E8), were investigated by surface tensiometry, ESR, and UV-visible absorption techniques. The surface tension data were treated with Rubingh's method for mixed micelle formation and Rosen's method for mixed monolayer formation at the aqueous solution/air interface. It was found that in the mixed micelle there is strong attractive interaction between cationic copper surfactant and anonic dodecyl sulfate while there is almost ideal mixing between copper surfactant and CTAB and C12E8. From the ESR and UV-visible studies, a mixed block-type arrangement of head groups is proposed. Copyright 1997 Academic Press. Copyright 1997Academic Press

Matched MeSH terms: Copper
Fulltext Heavy metal biomarker: fish behavior, cellular alteration, enzymatic reaction and proteomics approaches

Sabullah, M.K., Ahmad, S.A., Shukor, M.Y., Gansau, A.J., Syed, M.A., Sulaiman, M.R., et al.

International Food Research Journal, 2015;22(2):435-454.
MyJurnal

Due to the latest industrial development, many dangerous chemicals have been released directly or indirectly which resulted in the polluted water bodies. Water rehabilitation is an alternative way to restore the quality of water, followed by the environmental management to control the waste discharge to ensure the balance of the degradation rates or detoxifying by environmental factors. However, this process consumed a lot of time and cost. Besides, most of the metal ions, especially copper which is capable to bioaccumulate in aquatic organism and at the elevated level may cause physiological and biochemical alteration which leads to mortality. Environmental monitoring is the initial step presupposed evaluating the potential toxicity of effluent gushing at its purpose to discharge, avoiding the determining effects of contaminant in water bodies. Due to the high sensitivity of the aquatic life towards dissolving toxicant, the fish has been utilized as the biological measurement (Biomarker) to indicate the existence of toxicant exposure and/or the impact towards the evaluation of molecular, cellular to physiological level. Thus, this paper gives an overview of the manipulation of fish as a biomarker of heavy metals through behavior response, hepatocyte alteration, enzymatic reaction and proteomic studies which have proven to be very useful in the environmental pollution monitoring.

Matched MeSH terms: Copper
Mercury, lead, and other heavy metals in Chinese medicines

Wong MK, Koh LL

Biol Trace Elem Res, 1986 Aug;10(2):91-7.
PMID: 24254355 DOI: 10.1007/BF02795561

Ninety-nine samples of common Chinese medicines were purchased from Chinese medical shops in Singapore and Malaysia and analyzed for mercury, lead, copper, cadmium, cobalt, iron, and nickel. The majority of these medicines were manufactured in China, Hong Kong, and Malaysia. A few of them were of Singapore and Taiwan origin. Atomic absorption method (both flame and flameless) was used for the analyses. Mercury was found to be present in high concentrations in several of the medicines that were for oral consumption.

Matched MeSH terms: Copper
Fulltext Isolation and Characterisation of a Molybdenum-reducing and Metanil Yellow Dye-decolourising Bacillus sp. strain Neni-10 in Soils from West Sumatera, Indonesia

Mansur R, Gusmanizar N, Roslan MA, Ahmad SA, Shukor MY

Trop Life Sci Res, 2017 Jan;28(1):69-90.
PMID: 28228917 MyJurnal DOI: 10.21315/tlsr2017.28.1.5

A molybdenum reducing bacterium with the novel ability to decolorise the azo dye Metanil Yellow is reported. Optimal conditions for molybdenum reduction were pH 6.3 and at 34°C. Glucose was the best electron donor. Another requirement includes a narrow phosphate concentration between 2.5 and 7.5 mM. A time profile of Mo-blue production shows a lag period of approximately 12 hours, a maximum amount of Mo-blue produced at a molybdate concentration of 20 mM, and a peak production at 52 h of incubation. The heavy metals mercury, silver, copper and chromium inhibited reduction by 91.9, 82.7, 45.5 and 17.4%, respectively. A complete decolourisation of the dye Metanil Yellow at 100 and 150 mg/L occurred at day three and day six of incubations, respectively. Higher concentrations show partial degradation, with an approximately 20% decolourisation observed at 400 mg/L. The bacterium is partially identified based on biochemical analysis as Bacillus sp. strain Neni-10. The absorption spectrum of the Mo-blue suggested the compound is a reduced phosphomolybdate. The isolation of this bacterium, which shows heavy metal reduction and dye-decolorising ability, is sought after, particularly for bioremediation.

Matched MeSH terms: Copper
Fulltext Methane adsorption characteristics of copper oxide modified NaY zeolite adsorbents

Kamarudin, K.S.N., Chieng, Y.Y., Hamdan, H., Mat, H.

ASM Science Journal, 2010;4(1):29-40.
MyJurnal

Ordered microporous NaY zeolite and mesoporous copper oxide are high performance material as catalysts and adsorbents. The copper oxide-NaY zeolite modification in combination of their physicochemical properties could provide excellent opportunities for the creation of new gas adsorbents. In this study, modified NaY zeolite properties and methane adsorptive characteristics were investigated by dispersing copper oxide onto the NaY zeolite structure using the thermal dispersion method. The structures of the copper oxide modified zeolites were characterized by powder X-ray diffraction and Micromeritics ASAP 2000, while the methane adsorption characteristics were analyzed using a thermogravimetric analyzer. The results revealed that types of copper oxide, copper oxide loading concentration, calcination temperature and calcination time greatly affected the modified zeolite structure and gas methane adsorption characteristics.

Matched MeSH terms: Copper
Fulltext Biosorption of Pb (II) ions by immobilized cells of Pycnoporus Sanguineus in a packed bed column

Mashitah Mat Don, Yus Azila Yahaya, Bhatia, Subhash

Pertanika Journal of Science & Technology, 2009;17(1):-.
MyJurnal

The removal of heavy metals like lead, copper and cadmium from wastewater streams is an important environmental issue. The capability of immobilized Pycnoporus sanguineus (P. sanguineus), a white-rot macrofungi to remove heavy metals from aqueous solution in a packed bed column was investigated. Lead (Pb (II)) biosorption by immobilized cells of P. sanguineus was investigated in a packed bed column. The experiments were carried out by considering the effect of bed height (5-13 cm), flow rate (4-12 ml min-1) and initial lead (II) concentration (50-300 mg L-1). The breakthrough profiles showed that the saturation of metal ions was achieved faster for 5 cm bed height and 12 ml min-1 influent flow rate. However, the breakthrough time decreased as the initial metal concentration increased from 50 to 300 mg L-1. The column was regenerated using 0.1M HCl solution and biosorptiondesorption studies were carried out for 2 cycles. The results showed that the breakthrough time decreased as the number of cycle was proceeded.

Matched MeSH terms: Copper
Fulltext Mineral and heavy metal contents of marine fin fish in Langkawi island, Malaysia

Irwandi, J., Farida, O.

International Food Research Journal, 2009;16(1):105-112.
MyJurnal

A study was conducted to quantitate the concentrations of heavy metals, such as Hg, Pb and Cd in eight species of marine fin fish caught off the coast of Langkawi Island in Malaysia, as well as in its waters. The same fish were also used to determine the content of nutritional minerals, such as copper (Cu), zinc (Zn), calcium (Ca), and manganese (Mn).Fish and water samples were collected from four different areas, namely (1) Main Jetty Pulau Tuba (MJPT), (2) Teluk Cempedak Jetty (TCJ), (3) Simpang Tiga Chian Lian (STCL) and (4) Main Jetty Kuah (MJK) around Langkawi Island. Results showed that for the vital elements, all species had higher concentration of Zn compared to other elements. For the toxic elements, lead (Pb) and mercury (Hg) were found to have lower concentration of the mean values than the permissible limits set by FAO/WHO (1984). However, cadmium (Cd) level was slightly higher than the permissible limit but was still acceptable according to the Malaysian Food Regulation (1985). It can be concluded that all fish species studied are safe to be consumed.

Matched MeSH terms: Copper
Fulltext Mineral contents of selected marine fish and shellfish from the west coast of Peninsular Malaysia

Nurnadia, A.A., Azrina, A., Amin, I., Mohd Yunus, A.S., Mohd Izuan Effendi, H.

International Food Research Journal, 2013;20(1):431-437.
MyJurnal

The study was conducted to determine the mineral contents of 20 species of marine fish and 4 species of shellfish from the west coast of Peninsular Malaysia.Overall, the contents of micro minerals in all samples were below the permissible limits; except for oyster; with copper slightly higher than the limit set by FAO/WHO (1984), but below the limit set by Malaysian Food Regulations (1985); and zinc content higher than the limit set by Malaysian Food Regulations (1985), but below the limit set by FAO/WHO (1984). Meanwhile for macro minerals, most samples contained comparable sodium contents, significantly lower of potassium contents, higher calcium contents, and extremely higher of magnesium contents compared to the common ranges reported in the literatures. All samples were good sources of micro and macro minerals and could provide multi-health benefits if consumed in recommended amounts.

Matched MeSH terms: Copper
Fulltext Psychiatric Presentation in Wilson disease - Report of Two Cases

Nazariah Aiza, H., Aisah, A.R., Anita, C., Yeoh, S.H., Ng, C.G.

Malaysian Journal of Psychiatry, 2011;20(2):1-6.
MyJurnal

Wilson disease is an inherited metabolic disorder. It is an autosomal recessive disorder caused by mutation of ATP7B gene, which results in excessive accumulation of copper in the body and deposition in various organs. The clinical presentation varies and neuropsychiatric manifestations are common. It is a diagnostic challenge in the initial phase where it mimics other psychiatric conditions and the diagnosis of Wilson disease is based on a combination of laboratory tests and clinical features. Wilson disease treatment comprises of copper chelating therapy such as D-Penicillamine and zinc sulphate wheras the behavior and mood symptoms response well with atypical antipsychotic treatment. The present report illustrates two cases of Wilson disease in middle-aged patients. The first presentation involved changes in behavior and personality. There was some delay in making the diagnosis in the initial stage. Both cases were diagnosed to have Wilson disease after further investigations. Their condition improved with the combination of copper chelating agent and atypical antipsychotic. In conclusion, it emphasizes the awareness of psychiatric manifestations as the initial presentation of Wilson disease.

Matched MeSH terms: Copper
Fulltext Densification of in-situ copper-niobium carbide composite synthesized by mechanical alloying

Zuhailawati Hussain, Yong, Tuck Leong

Journal of Nuclear and Related Technologies, 2009;2009(1):135-140.
MyJurnal

In this paper, densification of in-situ copper-niobium carbide composite using cold pressing technique was addressed. Mixtures of Cu-20vol%NbC powder were prepared by two methods.
In first method, a mixture of Cu-15.79wt%Nb-2.04wt%C powder was milled at 400 rpm for 35 hours in a planetary mill. In second method, Cu and commercial NbC powder was mixed at 100 rpm for 2 hours in a jar mill. Then, both powders were pressed at different pressure (i.e. 350 MPa, 450 MPa, 550 MPa and 650 MPa) and sintered at 900 o C for 1 hour. Sample of in-situ and ex-situ Cu-20vol%NbC composite were characterized for density, hardness, phase formation by x-ray diffraction analysis and microstructure by scanning electron microscope. Xray diffraction analysis showed that NbC phase was formed in the in-situ processed sample. Hardness of in-situ processed copper composite was higher than that of the ex-situ processed copper composite due to good interface between coper matrix and niobium carbide reinforcement particle as well as distribution of finer niobium carbide particles in copper matrix. Sintered density of in-situ composite is lower than density of ex-situ composite beacuse of work hardening of the Cu-Nb-C mixture powder during powder to ball collision. Density and hardness of the in-situ and ex-situ Cu-20vol%NbC composites increase with the increase in compaction pressure as porosity is eliminated at higher compaction pressure.

Matched MeSH terms: Copper
Fulltext Development of internet-based instrumentation for the study of hall effect

Ariffin Abas, Abdul Halim Shaari, Zainal Abidin Talib, Zaidan Abdul Wahab

Pertanika Journal of Science & Technology, 2014;22(1):105-112.
MyJurnal

The computer, together with Lab View software, can be used as an automatic data acquisition system. This project deals with the development of a computer interfacing technique for the study of Hall Effect and converting the existing automation system into a Web-based automation system. The drive board RS 217-3611 with PCI 6025E card and stepper motor RS191-8340 with a resolution of 0.1mm, was used to move a pair of permanent magnets backward and forward against the sample. The General Interface Bus (GPIB) card interfaces, together with digital nano voltmeter and Tesla meter using serial port RS232 interface, are used for measuring the potential difference and magnetic field strength respectively. Hall Effect measurement on copper (Cu) and tantalum (Ta) showed negative and positive sign Hall coefficient. Therefore, the system has electron and hole charge carriers respectively at room temperature. The parameters such as drift velocity, conductivity, mobility, Hall Coefficient and charge carrier concentration were also automatically displayed on the front panel of Lab View programming and compared with standard value. The Web-based automation system can be remotely controlled and monitored by users in remote locations using only their web browsers. In addition, video conferencing through Net Meeting has been used to provide audio and video feedback to the client.

Matched MeSH terms: Copper
Fulltext Electron-phonon coupling constants of two-dimensional copper oxide-based high temperature superconductors

R. Abd-Shukor, W.Y. Lim

ASM Science Journal, 2013;7(1):18-22.
MyJurnal

The electron-phonon coupling constant of the copper oxide-based high temperature superconductors in the van Hove scenario was calculated using three known models and by employing various acoustic data. Three expressions for the transition temperature from the models were used to calculate the constants. All three models assumed a logarithmic singularity in the density of states near the Fermi surface. The calculated electron-phonon coupling constant ranged from 0.06 to 0.28. The constants increased with the transition temperature indicating a strong correlation between electron-phonon coupling and superconductivity in these materials. These values were smaller than the values estimated for the conventional three-dimensional BCS theory. The results were compared with previous reports on direct measurements of electron-phonon coupling constants in the copper oxide based superconductors.

Matched MeSH terms: Copper
Dietary copper and selenium are associated with insulin resistance in overweight and obese Malaysian adults

Tan PY, Soma Roy M

Nutr Res, 2021 09;93:38-47.
PMID: 34358885 DOI: 10.1016/j.nutres.2021.06.008

Imbalance in or inadequate intake of micronutrients may impair insulin synthesis, secretion, and it's signaling pathways. This study aimed to investigate the associations between dietary copper (Cu) and selenium (Se) with insulin resistance (IR), in overweight/obese adults. We hypothesized that dietary Cu and Se are associated with IR in a non-linear trend. A cross-sectional study was conducted on 128 non-diabetic overweight and obese Malaysian adults aged ≥18 years with a body mass index ≥23 kg/m2. Dietary intake was assessed using food frequency questionnaire. IR was defined as homeostatic model assessment-insulin resistance (HOMA-IR) ≥1.7. Locally weighted scatterplot smoothing regression was performed to detect non-linearity and piecewise regression models were computed to examine the trend of the associations at different cut off points. In this study, 45% (n = 57) of the study participants were found to be insulin resistant. A U-shaped non-linear relation between Se and HOMA-IR was observed. Three-piecewise regression models revealed positive association between Se and HOMA-IR in individuals with relatively low (<0.3 µg/kg/d) and high (≥1.01 µg/kg/d) intake of Se (β coefficient = 3.835, CI = -12.216 to 19.886, P= 0.614; and β coefficient = 0.785, CI = 0.386-1.185, P = 0.014, respectively). Significant positive association was only found between dietary Cu and HOMA-IR with intake of Cu ≥ 13.4 µg/kg/d, 0.276 (CI = 0.025-0.526; P = 0.033). In conclusion, our findings reveal that a critical balance in the dietary intake of copper and Se is crucial for health, more so in insulin resistant and diabetic individuals. In the latter treatment should include measured intake of both copper and Se, personalized according to individual habitual food preferences and intakes.

Matched MeSH terms: Copper
Fulltext Bending effects study on flexible wearable antenna for 2.45 GHz body centric wireless communications

Aslina A. Bakar, Amirul A. Mustafa, Ahmad R. Razali, Norhayati Mutalib, Amirudin Ibrahim

ESTEEM Academic Journal, 2020;16(2):75-87.
MyJurnal

This study aims to investigate the bending effects on the flexible wearable antenna by using copper nanowires and polydimethylsiloxane (PDMS). This project focuses on the bending effect on the proposed wearable antenna in the presence of skin tissue and at free space. The radiation characteristics were simulated and analyzed when the antenna was under flat and bent conditions. The performance result of return loss and radiation pattern (Efield and H-field) of proposed wearable antenna was analyzed. The material for the proposed antenna is designed to be flexible and wearable for the application of body-centric wireless communication (BCWCs) at the frequency of 2.45 GHz with the approval specifications of industrial, scientific and medical (ISM) band. Radiator for the proposed wearable antenna is fabricated using copper nanowire, and the antenna substrate is by using polydimethylsiloxane (PDMS). The performance result of the proposed wearable antenna was simulated by using CST microwave studio. From the simulated result for different bending angles, a conclusion was drawn that bending of structure can improve the impedance matching and return loss during the bent condition. However, the resonant frequency tends to shift as the antenna is bent up to 50°. At the critical angle of 70°, the frequency is shifted to a lower frequency.

Matched MeSH terms: Copper
Fulltext Hybrid Mold: Comparative Study of Rapid and Hard Tooling for Injection Molding Application Using Metal Epoxy Composite (MEC)

Hussin R, Sharif S, Nabiałek M, Zamree Abd Rahim S, Khushairi MTM, Suhaimi MA, et al.

Materials (Basel), 2021 Feb 01;14(3).
PMID: 33535504 DOI: 10.3390/ma14030665

The mold-making industry is currently facing several challenges, including new competitors in the market as well as the increasing demand for a low volume of precision moldings. The purpose of this research is to appraise a new formulation of Metal Epoxy Composite (MEC) materials as a mold insert. The fabrication of mold inserts using MEC provided commercial opportunities and an alternative rapid tooling method for injection molding application. It is hypothesized that the addition of filler particles such as brass and copper powders would be able to further increase mold performance such as compression strength and thermal properties, which are essential in the production of plastic parts for the new product development. This study involved four phases, which are epoxy matrix design, material properties characterization, mold design, and finally the fabrication of the mold insert. Epoxy resins filled with brass (EB) and copper (EC) powders were mixed separately into 10 wt% until 30 wt% of the mass composition ratio. Control factors such as degassing time, curing temperature, and mixing time to increase physical and mechanical properties were optimized using the Response Surface Method (RSM). The study provided optimum parameters for mixing epoxy resin with fillers, where the degassing time was found to be the critical factor with 35.91%, followed by curing temperature with 3.53% and mixing time with 2.08%. The mold inserts were fabricated for EB and EC at 30 wt% based on the optimization outcome from RSM and statistical ANOVA results. It was also revealed that the EC mold insert offers better cycle time compared to EB mold insert material.

Matched MeSH terms: Copper

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