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Article
Aerosol assisted dielectric barrier discharge plasma jet for Silver PMMA nanocomposite thin films preparation
بلازما نفث بالتفريغ الكهربائي عبر حاجز عازل والمعززة بالرذاذ لتحضير متراكبات فضة- PMMA

Authors: Hammad R. Humud --- Lubna Abd Al Kareem --- Abdulhadi Kadhim
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2015 Volume: 33 Issue: 7 Part (B) Scientific Pages: 1273-1282
Publisher: University of Technology الجامعة التكنولوجية

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Abstract

Silver Poly (methyl methacrylate) PMMA nanocomposite thin films deposited on glass substrates by in-situ aerosol assisted plasma polymerization at atmospheric pressure and room temperature, from methyl methacrylate monomer in the presence of different concentrations of Ag nanoparticles (3%, 5%, 7%, and 9wt%). The average particles size for the silver nanoparticles was within 50nm. Metal polymer nanocomposite thin films were characterized by UV-VIS, XRD, and SEM the optical studies show that the energy band gap will be different according to the silver PMMA concentration. The XRD pattern indicates that the pure PMMA is amorphous where The XRD pattern of Ag nanoparticles in PMMA, all the refractions corresponded to the pure silver metal with cubic symmetry. SEM and the XRD reveal the presence of silver nanoparticle embedded into PMMA. It can be concluded that it can be prepared Ag PMMA nanocomposite thin films by aerosol assisted dielectric barrier discharge DBD plasma jet polymerization and control the optical energy band gap irregulars by controlling the experiment variables.

تم ترسيب اغشية رقيقة نانوية لمتراكبات PMMA/Ag على قواعد من الزجاج وذلك بانجاز البلمرة موضعيا بالبلازما المعززة بالرذاذ وبدرجة حرارة الغرفة وعند الضغط الجوي ,من مونيمر MMA وبوجود تراكيز مختلفة من جسيمات الفضة النانوية (3%, 5%, 7%, and 9wt%)..معد قطر الجسيمات النانوية للفضة هي nm50 .الاغشية الرقيقة النانوية لمتراكبات معدن بوليمر شخصت بال UV-VIS, XRD و SEM,دراسة الخواص البصرية بينت ان فجوة الطاقة البصرية تتغير مع تغير تركيز الفضة في PMMA. حيود الشعة السينية بين ان PMMA ذو تركيب بنائي عشوائي بينما نمط حيود الاشعة السينية للفضة في PMMA كانت ناتجة عن فضة نقية ذات تركيب بلوري مكعب .فحوصات المجهر الالكتروني والاشعة السينية بينت ان جسيمات الفضة النانوية مزروعة بصورة متجانسة داخل ال PMMA.من هذا نستنتج امكانيت تحضير اغشية رقيقة لمتراكبات PMMA/Ag بالبلمرة الموضعية بالبلازما نفث الملولدة بالتفريغ الكهربائي عبر حاجز عازل DBD والتحكم بفجوة الطاقة البصرية بشكل منتضم وذلك بالتحكم بمتغيرات التجربة.

Keywords

PMMA --- nanocomposite --- plasma jet


Article
Polymer- Nanoparticles Composites for the Reduction of the Bacterial Adherence to Surfaces

Author: Muna Sabbar AL-Rubiae
Journal: Iraqi Journal of Biotechnology المجلة العراقية للتقانات الحياتية ISSN: 18154794 Year: 2016 Volume: 15 Issue: 3 Pages: 17-24
Publisher: Baghdad University جامعة بغداد

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Abstract

The medical device is one of the sources of nosocomial infections; the adherence of the bacteria on the surface of this device is the first step in the medical device related infection. In this study nanocomposite of polymethyl methacrylate (PMMA)/titanium oxide nanoparticles (1, 5, 10, 20, 30 wt %) and copolymer acrylonitrile butadiene styrene (ABS)/titanium oxide nanoparticles (1, 5, 10, 20, 30 wt %) were used to investigate the ability of the nanocomposite for the reduction of the bacterial adherence to the surfaces. The microorganisms which is used in this study include (Pseudomonas aeruginosa, Staphylococcus aureus and Klebsiella pneumonia). After an incubation of microorganisms with nanocomposites for 2 hours, it was found that the adhered bacterial cells were significantly reduced on all of the TiO2-containing nanocomposites in the comparison with control polymer. The reduction is reached to 60.82% with10% TiO2 in ABS for P. aeruginosa. The results of the S. aureus adherence on nanocomposite are revealed a significant reduction in the number of adhered bacteria and reached to 73.71% with 20% TiO2 in PMMA. The effect of TiO2 nanoparticales on the K. pneumonia adherence appeared very clear and the reduction uis reached to 90.04% with 10% TiO2 in ABS.


Article
The influence of adding of modified ZrO2-TiO2 nanoparticles on certain physical and mechanical properties of heat polymerized acrylic resin

Authors: Tiba A. Salman --- Hanan A. Khalaf
Journal: Journal of baghdad college of dentistry مجلة كلية طب الاسنان بغداد ISSN: 16800087 Year: 2015 Volume: 27 Issue: 3 Pages: 33-39
Publisher: Baghdad University جامعة بغداد

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Abstract

requirements of denture base materials. The purpose of this study was to produce new modified polymernanocomposite (PMMA /ZrO2-TiO2) andassess itsimpact strength, transverse strength and thermal conductivity incomparison to the conventionalheat polymerized acrylic resin.Materials and Methods: Both ZrO2 and TiO2nano fillers were silanized with TMSPM (trimethoxysilyl propyl methacrylate)silane coupling agent before beingdispersed by ultrasonication with the methylmethacrylate (monomer) and mixedwith the polymer by means of 2% by weight in (1:1) ratio, 60 specimens were constructed by conventional waterbath processing technique and divided into 2 groups: 30 specimens for control group 0% nanofillers and 30specimens for experimental group 2% of (1:1) ZrO2 and TiO2nano fillers then each group was subdivided into3 subgroupsaccording to the test to be conducted with 10 specimens for impact, transverse and thermal conductivitytest.Results: The interaction of TMSPM silane and the nanofillers was confirmed by FT-IR (Fourier Transform Infra-redspectrophotometer). High significant increase in impact strength (9.838) Kj/m2 and transverse strength (101.705)N/mm2 and non-significant increase in thermal conductivity (0.286) W/m.C° of heat cured acrylic resin of the newpolymer nanocomposite were observed.Conclusions: The addition of 2 wt.% of ZrO2:TiO2 by means of 1:1 ratio considerably improved the impact andtransverse strength and had a positive effect on the thermal conductivity


Article
Synthesis and Studying SomeMechanical Properties of Nanocomposite
تصنيع متراكب نانوي ودراسة بعض خواصه الميكانيكية

Authors: Fadhil A. Chyad --- Abdul-Raheem K.Abid Ali --- Auday A. Mehatlaf
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2013 Volume: 31 Issue: 7 Part (A) Engineering Pages: 1221-1228
Publisher: University of Technology الجامعة التكنولوجية

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Abstract

This study aims to synthesis a nanocomposite from Al2O3 – Cr2O3 and studying some of its mechanical properties like microhardness and fracture strength. X-Ray diffraction patterns shows a good crystallinity of the composite with very sharp and neat peaks. TEM photographs shows the good distribution of the particles which have an average particle size of (3-6 nm). The microhardness is increased with the increasing of sintering temperatures having the height value at 15% chromia while the fracture strength behaves as a bell shape having again the height value at 15% chromia.

الخلاصةيهدف البحث الى تحضير متراكب نانوي من الألومينا والكروميا ودراسة بعض الخواص الميكانيكية مثل الصلادة المجهرية ومتانة الكسر. أظهرت فحوصات حيود الأشعة السينية ببلورية جيدة لهذا المتراكب حيث القمم الحادة والنظيفة. أما صور المجهر الألكتروني الخارق اظهر ان توزيع الحجم الحبيبي جيد ومعدل الحجم الحبيبي(6-3)نانومتر. أزدادت قيم الصلادة بزيادة درجة حرارة التلبيد وكانت اعلى صلادة لنسبة 15% من الكروميا. اما متانة الكسر ايضا ازدادت مع نسبة الكروميا وايضا نسبة 15% هي الأعلى ومن ثم تبدأ بالنزول.


Article
Structure Properties of Graphene- polymer Nanocomposite

Author: Salam H. Ali
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2016 Volume: 34 Issue: 2 Part (B) Scientific Pages: 334-340
Publisher: University of Technology الجامعة التكنولوجية

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Abstract

In this work graphene-PVA composites samples prepared with different graphene loading (0.2, 0.5, 0.7, 1)gm, where prepared by direct mixing then dried at (60 C˚) in an oven. The present work focuses on studying the structural properties of composite, using analysis like X_ray diffraction, SEM and AFM. The results show that the chemical composition has major effect on structural properties, the phase analysis done by X_ray diffraction has confirmed the formation of the expected graphene structure where the crystal size was increased but the X-ray density was decreased when increasing the graphene content in PVA matrix. SEM shows surface image of composite films where the graphene nanoplates can be homogeneously integrated with in PVA matrix. AFM examinationshows that the surface roughness decreased with filler increasing.


Article
Characterization of silver polyaniline nanocomposite thin films prepared by microwave induced plasma
توصيف اغشية متراكبات متعدد الانيلين فضة النانوية الرقيقة المحضرة بالبلازما المحتثة بالامواج المايكروية

Authors: Ahmad S. Wassfi احمد سلمان وصفي --- Mohaned A. Abed مهند علي عبد
Journal: Iraqi Journal of Physics المجلة العراقية للفيزياء ISSN: 20704003 Year: 2015 Volume: 13 Issue: 28 Pages: 1-9
Publisher: Baghdad University جامعة بغداد

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Abstract

Polyaniline (PANI) and Ag/PANI nanocomposite thin films have prepared by microwave induced plasma. The Ag powder of average particle size of 50 nm, were used to prepare Ag/PANI nanocomposite thin films. The Ag/PANI nanocomposite thin films prepared by polymerization in plasma and characterized by UV-VIS, FTIR, AFM and SEM to study the effect of silver nanoparticles on the optical properties, morphology and structure of the thin films. The optical properties studies showed that the energy band gap of the Ag/PANI (5%wt silver) decreased from 3.6 to 3.2 eV, where the substrate location varied from 4.4 to 3.4 cm from the axis of the cylindrical plasma chamber. Also the optical energy gap decreased systematically from 3.3 to 3 eV with increasing Ag nanoparticles, where Ag concentration increased from 5% to 11%wt. The FTIR measurement showed a shifting in the FTIR absorption peaks with Ag concentration. AFM and SEM images indicate that there are a few clusters of Ag and there is a uniform distribution of the Ag nanoparticles in the PANI matrix. It can be concluded that Ag/PANI nanocomposite thin films with controlled optical energy band gap can be prepared by microwave induced plasma technique.

حضرت أغشية رقيقة للبولي أنيلين (PANI) و لمتراكب Ag/PANI بطريقة البلازما المحتثة بالمايكروويف. وكان معدل حجم مسحوق الفضة المستخدم 50 نانومتر. حضر المتراكب Ag/PANI بطريقة البلمرة بالبلازما وتم توصيف الأغشية الرقيقة الناتجة بوساطة UV-Vis, FTIR, AFM, SEM لدراسة تأثير الفضة على الخواص البصرية وشكل سطوح وتركيب الأغشية الرقيقة. دراسة الخواص البصرية بينت إن فجوة الطاقة للمتراكب Ag/PANI وبتركيز 5% نسبة وزنيه من الفضة قلت من 3.6-3.2 إلكترون فولت، حيث أن موقع أرضية الترسيب تغير من 4.4- 3.4 سم عن محور البلازما. أيضا فجوة الطاقة قلت من 3.3-3 إلكترون فولت مع زيادة تركيز جسيمات الفضة من 5% إلى 11% نسبه وزنيه. قياس الطيف للغشاء الرقيق بالأشعة تحت الحمراء بين إن هناك إزاحة في قمة الامتصاص مع إضافة جسيمات الفضه. صور AFM و SEM تشير إلى وجود تجمعات قليلة من جسيمات الفضة مع توزيع منتظم للجسيمات النانوية. ومن الممكن استنتاج إن هناك إمكانية السيطرة على فجوة الطاقة للأغشية الرقيقة للمتراكب النانوي Ag/PANI المحضرة بطريقة البلازما المحتثة بالمايكروويف.


Article
INVESTIGATION OF TEMPERATURE EFFECT FOR NANOCOMPOSITE MATERIALS SUBJECTED TO HIGH STRAIN RATE IMPACT
التحقق من تأثير درجة الحرارة على مواد نانوية معرضة الى صدم بمعدل أنفعال عالي

Authors: Samira K. Radhi --- Fadhel A. Al-Shukri --- Ali M. Ibraheem
Journal: Journal of Engineering and Sustainable Development مجلة الهندسة والتنمية المستدامة ISSN: 25200917 Year: 2016 Volume: 20 Issue: 4 Pages: 116-131
Publisher: Al-Mustansyriah University الجامعة المستنصرية

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Abstract

The study coversthe dynamic impact response of nanocomposite Alumina and nanocomposite carbon black particlesCB N220/Epoxy at room temperatures and 150 ℃at five velocities (16.58, 18.24, 19.88, 21.54 and 23.2) m/s by using a Hopkinson Split compressive Bar (HSPB).The nanocomposites samples with (2wt. % and 4 wt. %) of (Alumina and CB N220) were prepared without and with (25%) of unidirectional fiber glass. The results indicated that, maximum stress, strain and absorbed energy increased with increasing the strain rate for all types of these samples at room temperature. When increase the temperature to 150 ℃ it noted that the all values of stress, strain, strain rate and absorbed energy decreased with respect the values at room temperature. The determined Johnson-Cook parameters were found as the empirical fitting for data of stress (temperature, strain, and strain rate) with the curves of stress-strain, that are obtained from the compression tests.

تتضمن الدراسة تأثير الحرارة والصدمات بسرعات العالية على نوعين من المواد النانوية المركبة هما مادة الألوميناوالكاربون الأسود مع الأيبوكسي عند درجة حرارة الغرفة وعند ℃ 150 وبأستخدام خمس سرع: ,18.24 ,16.58 ), 19.8821.54, و 23.2 ( م/ثا بأستخدام عمود هوبكنسن للكبس المجزأ . تم تحضير اربعة أنواع من العينات لكل مادة من خلال التحكم بنسبةتركيز المادة النانوية وكذلك اضافة ) 25 %( أو عدم أضافة الألياف الزجاجية )أحادية الأتجاة( وبذلك تكون أنواع العينات هي: 2% , 4%بوجود وعدم وجود الألياف. تم خلط هذه المواد بجهاز التشتت بالموجات فوق الصوتية. بينت النتائج ان اعلى قيم للأجهاد , الأنفعالوالطاقة الممتصة تزداد بزيادة معدل الأنفعال. عند زيادة الحرارة الى ℃ 150 وجد أن قيم كل من الأجهاد, الأنفعال, معدل الأنفعالوالطاقة الممتصة تقل بالنسبة الى قيم درجة حرارة الغرفة. تم حساب متغيرات معادلة جونسون كوك )معادلة تربط بين الأجهاد –والأنفعال ومعدل الأنفعال ودرجة الحرارة( ومن خلالها تم رسم مخطط الأجهاد والأنفعال نظرياً ومقارنته مع النتائج العملية.


Article
Synthesized and Study the Structural and Morphological Properties of Polyaniline-Cadmium Sulfide Nanocomposite

Authors: Sewench N. Rafic --- Selma M. H. Al-Jawad --- Mustafa M. Muhsen
Journal: Al-Nahrain Journal of Science مجلة النهرين للعلوم ISSN: (print)26635453,(online)26635461 Year: 2017 Volume: 20 Issue: 3 Pages: 91-98
Publisher: Al-Nahrain University جامعة النهرين

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Abstract

The nanocrystalline CdS powder was prepared using sol–gel method. The polyaniline were prepared using chemical oxidative polymerization of aniline. The PANI-CdS nanocomposites had been prepared via same method of polyaniline preparation and different concentrations of CdS (10, 20, 30, 40 and 50 wt%) were added. X-ray diffraction shows that the peaks of emeraldine salt polyaniline powder are located at 2θ = 21.5o, 25.7o and 28.1o which indicate of polycrystalline polyaniline and the peaks of CdS powder are located at 2θ = 26.69, which is indicate of crystalline CdS coincides with hexagonal [002] structure, 2θ = 47.47 which is refers to CdS with hexagonal [103] and cubic [220] structures. The crystallite size of PANI and CdS were found to be 7.95 and 12.09 nm respectively. FTIR measurement indicates that there are interaction between polyaniline matrix and CdS nanoparticles. The AFM investigation shows that there is uniform distribution for CdS nanoparticles in the PANI matrix.


Article
Testing Different Properties of A Light-Cured Denture Base Material After Addition of Silicon Oxide Nanofiller (An in Vitro Study)

Author: Mohammed Moudhaffer M Ali
Journal: Journal of baghdad college of dentistry مجلة كلية طب الاسنان بغداد ISSN: 16800087 Year: 2017 Volume: 29 Issue: 1 Pages: 47-54
Publisher: Baghdad University جامعة بغداد

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Abstract

Background: Improving the properties of heat- cured and self-cured acrylic resin have been studied by many researchers. However, little studies concerned with visible light cured resin (VLCR) improved through addition of nanofiller are available. The purpose of this study was to evaluate some properties of (VLCR) after addition of SiO2 nanofiller.Materials and Methods: SiO2 nanofiller were added to (VLCR) tray material after being dissolved in tetrahydrofuran (THF) solvent. According to the pilot study 2% SiO2 nanofiller addition exhibited better properties than the other percentages (1%, 3%). The main study conducted involved (100) specimens divided into 5 groups according to the test included. (20) Specimens were selected for each test (10 samples for the control group and 10 samples for the experimental 2% SiO2 nanofiller group). The properties investigated were transverse strength, impact strength, surface hardness, surface roughness, water sorption and solubility. Scanning electron microscope (SEM) and energy dispersive spectroscopy (EDS) were used to assess nanofiller distribution and identification of elements. The data were subjected to descriptive statistical analysis and independent sample t-test.Results: The mean value of transverse strength of experimental group increased significantly, while the impact strength of experimental group decreased significantly when compared to control group. A significant increase in surface hardness was noticed in the experimental group, while non-significant increase in surface roughness was observed. The water sorption values were decreased significantly, while a non-significant decrease in water solubility was observed in the experimental group.Conclusion: Addition of SiO2 nanofiller to (VLCR), slightly improve the transverse strength and surface hardness, while water sorption and solubility slightly decreased. The impact strength was significantly deteriorated, while the surface roughness shows non-significant increment


Article
Synthesis and Optical Characterization of Ag/PVA Nanocomposites Films

Author: Hussein T. Salloom
Journal: Al-Nahrain Journal of Science مجلة النهرين للعلوم ISSN: (print)26635453,(online)26635461 Year: 2017 Volume: 20 Issue: 4 Pages: 56-63
Publisher: Al-Nahrain University جامعة النهرين

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Silver- Poly vinyl alcohol Ag/ PVA nanocomposite films were prepared by casting method at room temperature with different amount of AgNO3 solution (0.001, 0.0015, and 0.002ml). The prepared nanocomposites were characterized using UV–VIS spectrophotometer and the optical properties were investigated in the wavelength range 300-800 nm. The absorption peaks showed a shift towards higher wavelength with increasing AgNO3 concentration while the energy band gap and absorption edges shifted towards lower energies with the increase of AgNO3 concentration.

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