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EVA/zinc oxide nanocomposites for active food packaging : selected physical, and microbial properties

Majeed Haza Satar, Al-Juboory Farah Khalaf Hammoud, Hamid Raghad Ali, Zawawi Ruzniza Mohd

Polimery

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2023

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Vol. 68, nr 3

135--141

EN

The melt-mixing method was used to obtain nanocomposites of poly(ethylene-co-vinyl acetate) (EVA) with 1, 3 or 5 wt% of hydrophilic zinc oxide (ZnO) nanoparticles. The contact angle, barrier and antimicrobial properties of the obtained composites were investigated. The nanocomposites were characterized by better hydrophilic and barrier properties, as evidenced by, respectively, a smaller contact angle and lower water vapor permeability and water absorption compared to EVA, which can be explained by the formation of hydrogen bonds between EVA and ZnO. In addition, the composites were characterized by greater bactericidal activity against E. coli and S. aureus. The optimal physical and microbial properties were obtained with 3 wt% ZnO content.

PL

Metodą mieszania w stanie stopionym otrzymano nanokompozyty kopolimeru etylen-octan winylu (EVA) z dodatkiem 1, 3 lub 5% mas. hydrofilowych nanocząstek tlenku cynku (ZnO). Zbadano kąt zwilżania, właściwości barierowe i przeciwdrobnoustrojowe otrzymanych kompozytów. Nanokompozyty charakteryzowały się lepszymi właściwości hydrofilowymi i barierowymi, o czym świadczy, odpowiednio, mniejszy kąt zwilżania oraz mniejsza przepuszczalność pary wodnej i absorp¬cja wody w porównaniu z EVA, co można wyjaśnić tworzeniem się wiązań wodorowych pomiędzy EVA i ZnO. Ponadto kompozyty miały większą aktywność bakteriobójczą wobec E. coli i S. aureus. Optymalny zespół właściwości uzyskano przy 3% mas. zawartości ZnO.

2

Multifunctional Finishing of Cotton Fabric

Aslam Sameen, Hussain Tanveer, Ashraf Munir, Tabassum Madeeha, Rehman Abdur, Iqbal Kashif, Javid Amjed

Autex Research Journal

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2019

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Vol. 19, no. 2

191--200

EN

The research in textiles is being driven by ecology, economy, and functionality. Therefore, the present research is focused on the development of multifunctional textiles that consume minimum energy during their processing, eco-friendly chemicals for functionalization, and use short processing steps. Eco-friendly cross-linkers such as butanetetracarboxylic acid and zinc oxide nanoparticles are used to impart wrinkle recovery, antibacterial activity, ultraviolet (UV) protection, bending rigidity, and antistatic properties to cotton fabric just in one step. The treated fabric has been characterized with Fourier-transform infrared spectrophotometer, scanning electron microscope, and X-ray diffractometer. Wrinkle recovery, tear strength, antibacterial activity, UV protection, and antistatic properties were tested with AATCC 66-1990, ASTM D 1224, AATCC 147, AATCC 183, and UNI EN 1149, respectively. The treated fabric shows excellent functional properties up to 20 washing cycles.

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A novel photoelectrode of NiO@ZnO nanocomposite prepared by Pechini method coupled with PLD for efficiency enhancement in DSSCs

Nada A. A., Selim H., Bechelany M., El-Sayed M., Hegazey R. M., Souaya E. R., Kotkata M. F.

Materials Science Poland

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2018

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Vol. 36, No. 2

327--336

EN

The dye-sensitized solar cells made of NiO@ZnO nanoparticles were synthesized by a novel Pechini route using different NiO molar concentration ratios. The thermal, structural morphological, optical and electrical properties of the prepared samples were investigated using thermal gravimetric analysis and differential scanning calorimetery (TGA/DSC), X-ray diffraction (XRD), high-resolution transmission electron microscopy (HR-TEM), FT-IR and Raman spectroscopy, UV-diffuse reflectance (UV-DRS), photoluminescence (PL) and current-voltage (I-V) measurements. The success of doping process was confirmed by the XRD patterns, which revealed the existence of new peak at 43.2° corresponding to secondary phase NiO. UV spectra exhibited red shifts in NiO doped ZnO NCs and PL spectra showed strong emission band at 355 nm. The doping of ZnO with NiO was intended to enhance the surface defects of ZnO. The current-voltage measurements showed an improvement of the short circuit photocurrent (Jsc) and fill factor (FF) and a decrease in the open circuit voltage (VOC) for dye-sensitized solar cel (DSSC) based on NiO–ZnO NCs. A clear enhancement in efficiency of DSSC from 1.26±0.10 % for pure ZnO to 3.01±0.25 % for NiO–ZnO NCs at the optimum doping with 1.5 mol% of NiO to ZnO (ZN1.5) was observed. The obtained material can be a suitable candidate for photovoltaic applications.

4

Optical properties of PVP/ZnO composite thin films

Tański T., Matysiak W.

Journal of Achievements in Materials and Manufacturing Engineering

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2017

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Vol. 82, nr 1

5--11

EN

Purpose: The aim of the work was the preparation of thin composite layers from PVP polymer doped by ZnO nanoparticles using the spin coating method and the analysis of the applied reinforcing phase on the morphology and optical properties of obtained composites. Design/methodology/approach: To analyse the morphology of thin coatings a technique of surface topography imaging using the atomic force microscopy (AFM) was applied. Analysis of the optical properties was conducted using absorbance spectrum in function of wavelength for all produced thin coatings using UV-Vis spectroscopy. Findings: AFM results show that mass concentration of ZnO nanoparticles of 10% in a solution of PVP/EtOH polymers has a meaningful influence on the morphology of the surface of the PVP/ZnO composite coatings. Using obtained absorbance spectra, the width of the band gap of the manufactured composite coatings were determined which were compared with a band gap values of pure polymer and used reinforcing phase. Practical implications: The analysis of the values of the energy band gap of the manufactured materials showed that both for pure polymer and composite coatings values of energy band gap are similar approx. 4 eV at the same time decrease the degree of absorption of electromagnetic radiation caused by the increasing concentration of the reinforcing phase, which indicates the broad possibilities of application of this type of the material.

5

Effect of NaOH concentration on optical properties of zinc oxide nanoparticles

Koutu V., Shastri L., Malik M. M.

Materials Science Poland

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2016

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Vol. 34, No. 4

819--827

EN

In the present work, powder zinc oxide samples were prepared by varying NaOH concentration (0.1 M – 0.4 M) using wet-chemical co-precipitation method. As-synthesized ZnO was characterized using X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), photoluminescence (PL) and Raman spectroscopy. Formation of hexagonal wurtzite structure of the ZnO samples has been revealed from XRD studies. This study further suggests reduction in crystallite size from 40 nm to 23 nm with an increase in NaOH concentration which is confirmed by FESEM. PL and Raman spectroscopy studies of these samples show significant peak shift towards the higher and lower energy respectively, with maximum PL emission between 400 nm and 470 nm region of the visible spectrum. Noticeable inverse relationship between optical properties of ZnO nanoparticles and NaOH concentration may be attributed to the rapid nucleation during the synthesis process. With these remarkable properties, ZnO nanoparticles may find applications in nanoelectronic devices, sensors, nanomedicine, GATE dielectrics, photovoltaic devices, etc.

6

Effect of calcination temperature on the structural, optical and magnetic properties of pure and Fe-doped ZnO nanoparticles

Singh R. P. P., Hudiara I. S., Rana S. B.

Materials Science Poland

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2016

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Vol. 34, No. 2

451--459

EN

In the present study, pure ZnO and Fe-doped ZnO (Zn0.97Fe0.03O) nanoparticles were synthesized by simple coprecipitation method with zinc acetate, ferric nitrate and sodium hydroxide precursors. Pure ZnO and Fe-doped ZnO were further calcined at 450 ºC, 600 ºC and 750 ºC for 2 h. The structural, morphological and optical properties of the samples were characterized by X-ray diffractometer (XRD), scanning electron microscope (SEM), energy dispersive spectroscopy (EDS) and UV-Vis absorption spectroscopy. The X-ray diffraction studies revealed that the as-synthesized pure and doped ZnO nanoparticles have hexagonal wurtzite structure. The average crystallite size was calculated using Debye-Scherrer’s formula. The particle size was found to be in nano range and increased with an increase in calcination temperature. SEM micrographs confirmed the formation of spherical nanoparticles. Elemental compositions of various elements in pure and doped ZnO nanoparticles were determined by EDX spectroscopy. UV-Vis absorption spectra showed red shift (decrease in band gap) with increasing calcination temperature. Effect of calcination on the magnetic properties of Fe-doped ZnO sample was also studied using vibrating sample magnetometer (VSM). M-H curves at room temperature revealed that coercivity and remanent polarization increase with an increase in calcination temperature from 450 ºC to 750 ºC, whereas reverse effect was observed for magnetization saturation.

7

Antibacterial Composite Layers on Ti: Role of ZnO Nanoparticles

Roguska A., Belcarz A., Suchecki P., Andrzejczuk M., Lewandowska M.

Archives of Metallurgy and Materials

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2016

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Vol. 61, iss. 1

213--216

EN

Problem of Post-operative infections of implant materials caused by bacterial adhesion to their surfaces is very serious. Enhancement of antibacterial properties is potentially beneficial for biomaterials value. Therefore, the metallic and metallic oxide nanoparticles attract particular attention as antimicrobial factors. The aim of this work was to create nanotubular (NT) oxide layers on Ti with the addition of ZnO nanoparticles, designed for antibacterial biomedical coatings. Antimicrobial activities of titanium, TiO2 NT and ZnO/TiO2 NT surfaces were evaluated against bacterial strain typical for orthopaedic infections: S. epidermidis. TiO2 NT alone killed the free bacterial cells significantly but promoted their adhesion to the surfaces. The presence of moderate amount of ZnO nanoparticles significantly reduced the S. epidermidis cells adhesion and viability of bacterial cells in contact with modified surfaces. However, higher amount of loaded nanoZnO showed the reduced antimicrobial properties than the medium amount, suggesting the overdose effect.

8

Antibacterial Composite Layers on Ti: Role of ZnO Nanoparticles

Roguska A., Belcarz A., Suchecki P., Andrzejczuk M., Lewandowska M.

Archives of Metallurgy and Materials

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2016

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Vol. 61, iss. 2B

937--940

EN

Problem of post-operative infections of implant materials caused by bacterial adhesion to their surfaces is very serious. Enhancement of antibacterial properties is potentially beneficial for biomaterials value. Therefore, the metallic and metallic oxide nanoparticles attract particular attention as antimicrobial factors. The aim of this work was to create nanotubular (NT) oxide layers on Ti with the addition of ZnO nanoparticles, designed for antibacterial biomedical coatings. Antimicrobial activities of titanium, TiO2 NT and ZnO/TiO2 NT surfaces were evaluated against bacterial strain typical for orthopaedic infections: S. epidermidis. TiO2 NT alone killed the free bacterial cells significantly but promoted their adhesion to the surfaces. The presence of moderate amount of ZnO nanoparticles significantly reduced the S. epidermidis cells adhesion and viability of bacterial cells in contact with modified surfaces. However, higher amount of loaded nanoZnO showed the reduced antimicrobial properties than the medium amount, suggesting the overdose effect.

9

Preparation and characterization of ZnO-PMMA resin nanocomposites for denture bases

Cierech M., Wojnarowicz J., Szmigiel D., Bączkowski B., Grudniak A. M., Wolska K. I., Łojkowski W., Mierzwińska-Nastalska E.

Acta of Bioengineering and Biomechanics

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2016

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Vol. 18, no. 2

31--41

EN

Purpose: The aim of the paper was to investigate the antifungal activity of zinc oxide nanoparticles (ZnONPs) against Candida albicans. Some attempts have been made to find out the best way to introduce ZnONPs into polymethyl methacrylate (PMMA) resin material and to determine some parameters of a newly formed composite. Material and methods: Zinc oxide nanoparticles were manufactured and their basic physical parameters were determined (average particle size, density, specific surface area). Minimal inhibitory concentration (MIC) of ZnONPs was determined for the Candida albicans standard strain. The average size of ZnO conglomerates in the monomer solution of PMMA resin was measured using a dynamic light scattering instrument. PMMA resin samples with incorporated ZnONPs were produced. The morphology of nanopowder and the newly formed composite was examined under a scanning electron microscope (SEM). In addition, the roughness parameter of PMMA resin material was investigated before and after ZnONPs modification. Results: Nanopowder with the average particle size of 30 nm, density of 5.24 g/cm3 and surface area of 39 m2 /g was obtained. MIC was determined at the level of 0.75 mg/mL. The average size of ZnO conglomerates in the monomer solution of acrylic resin dropped by 11 times after ultrasound activation. SEM examination of a newly formed composite showed a successful introduction of ZnONPs confirmed by the energy dispersive X-ray spectroscopy (EDS) analysis. There were no statistically significant differences in the biomaterial roughness before and after the modification of ZnONPs. Conclusion: Zinc oxide nanoparticles were successfully incorporated into acrylic resin used for the production of denture bases. The presence of nanoparticles with sizes below 100 nm was confirmed. Nevertheless a newly created composite needs to be further investigated to improve its homogeneity, and to check its microbiological properties, strength and biocompatibility prior to its possible clinical use.

10

Effect of doping on structural and optical properties of ZnO nanoparticles: study of antibacterial properties

Maddahi P, Shahtahmasebi N, Kompany A., Mashreghi M, Safaee S, Roozban F

Materials Science Poland

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2014

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Vol. 32, No. 2

130—135

EN

Sol-gel method was successfully used for synthesis of ZnO nanoparticles doped with 10 % Mg or Cu. The structure, morphology and optical properties of the prepared nanoparticles were studied as a function of doping content. The synthesized ZnO:(Mg/Cu) samples were characterized using XRD, TEM, FTIR and UV-Vis spectroscopy techniques. The samples show hexagonal wurtzite structure, and the phase segregation takes place for Cu doping. Optical studies revealed that Mg doping increases the energy band gap while Cu incorporation results in decrease of the band gap. The antibacterial activities of the nanoparticles were tested against Escherichia coli (Gram negative bacteria) cultures. It was found that both pure and doped ZnO nanosuspensions show good antibacterial activity which increases with copper doping, and slightly decreases with adding Mg.

11

Synthesis of ZnO nanoparticles by thermal decomposition of basic zinc carbonate

Hutera B., Kmita A., Olejnik E., Tokarski T.

Archives of Metallurgy and Materials

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2013

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Vol. 58, iss. 2

489--491

EN

The paper presents a method for obtaining nanoparticles of ZnO by thermal decomposition of the Zn-containing compounds. The experiment was based on the thermal decomposition of basic zinc carbonate to zinc oxide (with a content of 58-61 wt.%). Basic zinc carbonate was analysed by derivatography and then annealed at a selected temperature (about 600ºC) for about 1 h. Products of thermal decomposition of the compound were studied by XRD analysis and SEM scanning microscopy.

PL

W pracy zaprezentowano metodę otrzymywania nanocząstek ZnO na drodze termicznego rozkładu związków zawierających Zn. W eksperymencie wykorzystano termiczny rozkład zasadowego węglanu tlenku cynku (o zawartości od 58-61% mas.). Zasadowy węglan cynku poddano analizie derywatograficznej a następnie wygrzewaniu w określonej temperaturze (ok. 600ºC przez ok. 1 godz.). Produkty termicznego rozkładu związku badano analizą XRD oraz mikroskopia skaningowa SEM.

12

Effect of water glass modification with nanoparticles of zinc oxide on selected physical and chemical properties of binder and mechanical properties of sand mixture

Kmita A., Hutera B., Olejnik E., Janas A.

Archives of Foundry Engineering

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2012

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Vol. 12, iss. 2s

37--40

EN

In this paper, an attempt was made to use the ZnO nanoparticles as a modifier of foundry binder - water glass. The modifier was a colloidal suspension of the ZnO zinc oxide nanoparticles in propanol. A thermal method to obtain metal oxide nanoparticles was adopted. The modifier was product of the thermal decomposition of the basic zinc carbonate ([ZnCO3]2•[Zn(OH)2]3), and was introduced into the water glass in an amount of 1 and 3 wt%. To determine the interfacial reactions taking place in a quartz - modified water glass system, the binder wettability of the quartz grains was measured. The effect of water glass modification on the mechanical properties of moulding sands was verified by testing the tensile strength Rmu of moulding sands with the modified binders. Water glass modification with the colloidal solution of ZnO nanoparticles in propanol confirmed the effect of modifier on the water glass wettability of sand grains and on the mechanical properties of the sand mixtures with this additive.

13

Effect of water glass modification on its viscosity and wettability of quartz grains

Kmita A., Hutera B.

Archives of Foundry Engineering

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2012

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Vol. 12, iss. 3

59-62

EN

The aim of the present study was to develop a modifier for water glass. The method of thermal generation of metal oxide nanoparticles was adapted and used in the research. Nanoparticles of ZnO from the thermal decomposition of basic zinc carbonate were used. A method for the modifier introduction was developed, and the effect of modifier content and organic solvent type on the physico-chemical properties of binder (viscosity) and quartz wettability was determined. Binder viscosity was examined from the flow curves plotted with the help of a RHEOTEST 2 rotational rheometer equipped with proper software. Quartz wettability was determined examining time-related changes in the value of the contact angle in a quartz-binder system, until full stabilisation of the angle value has been achieved. Binder modification was carried out on sodium water glass designated as R"145". The water glass modifiers were suspensions of ZnO nanoparticles in propanol and methanol at a fixed concentration of c = 0.3 M and with the size of nanoparticles comprised in a range of <61 - 981 nm>. Water glass modification with the suspensions of ZnO nanoparticles in methanol and propanol showed the effect of modifier on the water glass viscosity and quartz wettability. This effect depends on the type of alcohol used. The ZnO suspension in propanol (alcohol with a longer hydrocarbon chain) affects more strongly the viscosity of binder and quartz wettability than the methanol suspension.