scholarly journals Facile Synthesis of Magnetic Copolymer Microspheres Based on Poly(glycidyl methacrylate-co-N-isopropylacrylamide)/Fe3O4by Suspension Photopolymerization

2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
Siti Zulaikha Mazlan ◽  
Faszly Rahim ◽  
Sharina Abu Hanifah
Keyword(s):  
Glycidyl Methacrylate ◽  
Chemical Interaction ◽  
Epoxy Group ◽  
Single Step ◽  
Magnetic Microspheres ◽  
Poly Vinyl Alcohol ◽  
Secondary Amide ◽  
Infrared Analysis ◽  
X Ray Diffraction ◽  
X Ray

Magnetic copolymer based on poly(glycidyl methacrylate-co-N-isopropylacrylamide) microspheres was prepared by 2,2-dimethoxy-2-phenylacetophenone- (DMPP-) photo initiated and poly(vinyl alcohol)- (PVA-) stabilized single step suspension photopolymerization. The effect of chemical interaction, morphology, and thermal properties by adding 0.1% w/v Fe3O4in the copolymer was investigated. Infrared analysis (FTIR) showed that (C=C) band disappeared after copolymerization, indicating that the magnetic copolymer microspheres were successfully synthesized and two important bands at 908 cm−1and 1550 cm−1appear. These are associated with the epoxy group stretching of GMA and secondary amide (N–H/C–H) deformation vibration of NIPAAm in magnetic microspheres. The X-ray diffraction (XRD) result proved the incorporation of Fe3O4nanoparticles with copolymer microspheres as peak of Fe3O4was observed. Morphology study revealed that magnetic copolymer exhibited uniform spheres and smoother appearance when entrapped with Fe3O4nanoparticles. The lowest percentage of Fe3O4nanoparticles leached from the copolymer microspheres was obtained at pH 7. Finally, thermal property of the copolymer microspheres was improved by adding a small amount of Fe3O4nanoparticles that has been shown from the thermogram.

scholarly journals Laser-Induced Deposition of Plasmonic Ag and Pt Nanoparticles, and Periodic Arrays

Materials ◽  
2020 ◽  
Vol 14 (1) ◽  
pp. 10
Author(s):  
Daria V. Mamonova ◽  
Anna A. Vasileva ◽  
Yuri V. Petrov ◽  
Denis V. Danilov ◽  
Ilya E. Kolesnikov ◽  
...  
Keyword(s):  
Substrate Surface ◽  
Pt Nanoparticles ◽  
Single Step ◽  
X Ray Diffraction ◽  
Ag Nps ◽  
X Ray ◽  
Periodic Arrays ◽  
Potential Applications ◽  
Surface Decoration ◽  
Wide Potential

Surfaces functionalized with metal nanoparticles (NPs) are of great interest due to their wide potential applications in sensing, biomedicine, nanophotonics, etc. However, the precisely controllable decoration with plasmonic nanoparticles requires sophisticated techniques that are often multistep and complex. Here, we present a laser-induced deposition (LID) approach allowing for single-step surface decoration with NPs of controllable composition, morphology, and spatial distribution. The formation of Ag, Pt, and mixed Ag-Pt nanoparticles on a substrate surface was successfully demonstrated as a result of the LID process from commercially available precursors. The deposited nanoparticles were characterized with SEM, TEM, EDX, X-ray diffraction, and UV-VIS absorption spectroscopy, which confirmed the formation of crystalline nanoparticles of Pt (3–5 nm) and Ag (ca. 100 nm) with plasmonic properties. The advantageous features of the LID process allow us to demonstrate the spatially selective deposition of plasmonic NPs in a laser interference pattern, and thereby, the formation of periodic arrays of Ag NPs forming diffraction grating

Facile Refluxing Synthesis of Hydroxyapatite Nanoparticles

2015 ◽  
Vol 68 (8) ◽  
pp. 1293 ◽  
Author(s):  
Pakvipar Chaopanich ◽  
Punnama Siriphannon
Keyword(s):  
Crystallite Size ◽  
Reaction Times ◽  
Single Step ◽  
Hydroxyapatite Nanoparticles ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Aqueous Mixture ◽  
Diffraction Patterns ◽  
Microscopy Images

Hydroxyapatite (HAp) nanoparticles were successfully synthesized from an aqueous mixture of Ca(NO3)2·4H2O and (NH4)2HPO4 by a facile single-step refluxing method using polystyrene sulfonate (PSS) as a template. The effects of reaction times, pH, and PSS concentration on the HAp formation were investigated. It was found that the crystalline HAp was obtained under all conditions after refluxing the precursors for 3 and 6 h. The longer refluxing time, the greater the crystallinity and the larger the crystallite size of the HAp nanoparticles. The HAp with poor crystallinity was obtained at pH 8.5; however, the well-crystallized HAp was obtained when reaction pH was increased to 9.5 and 10.5. In addition, the X-ray diffraction patterns revealed that the presence of PSS template caused the reduction of HAp crystallite size along the (002) plane from 52.6 nm of non-template HAp to 43.4 nm and 41.4 nm of HAp with 0.05 and 0.2 wt-% PSS template, respectively. Transmission electron microscopy images of the synthesized HAp revealed the rod-shaped crystals of all samples. The synthesized HAp nanoparticles were modified by l-aspartic acid (Asp) and l-arginine (Arg), having negative and positive charges, respectively. It was found that the zeta potential of HAp was significantly changed from +5.46 to –24.70 mV after modification with Asp, whereas it was +4.72 mV in the Arg-modified HAp. These results suggested that the negatively charged amino acid was preferentially adsorbed onto the synthesized HAp surface.

scholarly journals Preparation and Assessment of Heat-Treated α-Chitin Nanowhiskers Reinforced Poly(viny alcohol) Film for Packaging Application

Materials ◽  
2018 ◽  
Vol 11 (10) ◽  
pp. 1883 ◽  
Author(s):  
Chao Peng ◽  
Guangxue Chen
Keyword(s):  
Heat Treatment ◽  
Composite Films ◽  
Barrier Properties ◽  
Mechanical Tests ◽  
Light Transmittance ◽  
Poly Vinyl Alcohol ◽  
X Ray Diffraction ◽  
X Ray ◽  
Heat Treated ◽  
Chitin Nanowhiskers

In this study, poly(vinyl alcohol) (PVA) composite films enhanced by α-chitin nanowhiskers (ChWs) were prepared through heat treatment. The obtained membranes were assessed by means of FTIR spectroscopy, X-ray diffraction, thermogravimetric analysis, regular light transmittance, mechanical tests, permeability and water absorption. The influence of the nano-component and heat treatment on the mechanical, thermal and water-resistant properties of the composite membrane were analyzed. From the results of the work, the produced films with excellent barrier properties and inexpensive raw processed materials have great prospects in packaging applications.

Investigation of Ti Doping on the Structural, Optical and Magnetic Properties of ZnO Nanoparticles

2021 ◽  
Author(s):  
Raji P ◽  
K Balachandra Kumar
Keyword(s):  
Hexagonal Wurtzite Structure ◽  
Xrd Analysis ◽  
Infrared Analysis ◽  
Near Band Edge ◽  
Band Edge Emission ◽  
X Ray Diffraction ◽  
Absorption Bands ◽  
X Ray ◽  
Co Precipitation ◽  
Ti Doping

Abstract Ti - doped ZnO (TixZn1-xO x= 0.00, 0.05, 0.10, 0.15) nanoparticles have been synthesized through co - precipitation approach. X-ray diffraction (XRD), scanning electron microscopy (SEM), photoluminescence (PL), UV-Visible spectroscopy, and Vibrating Sample Magnetometer (VSM) have been used to characterize the samples. X-Ray Diffraction (XRD) analysis manifested the hexagonal wurtzite structure. The crystallite size decreased from 37 ​nm to 29 ​nm as dopant concentration is increased. Fourier transform infrared analysis showed the absorption bands of ZnO, with few within the intensities. SEM investigation showed the irregular shape and agglomeration of the particles. Ti, Zn, and O composition were determined from EDX analysis and confirmed the purity of the samples.PL spectra showed a near band edge emission and visible emission.Vibrating sample magnetometer (VSM) demonstrated pure and doped samples exhibited ferromagnetism behavior at room temperature.

Characteristics of Pentacene with Different Polymer Gate Insulators for Organic Thin-Film Transistors

2007 ◽  
Vol 124-126 ◽  
pp. 451-454 ◽  
Author(s):  
Jung Min Kim ◽  
Hyun Jung Her ◽  
J.H. Yoon ◽  
Jae Wan Kim ◽  
Y.J. Choi ◽  
...  
Keyword(s):  
Thin Films ◽  
Gate Insulator ◽  
Poly Vinyl Alcohol ◽  
Organic Thin Film ◽  
X Ray Diffraction ◽  
Polymer Substrates ◽  
X Ray ◽  
Gate Insulators ◽  
Atomic Force ◽  
Substrate Temperatures

We investigated the characteristics of pentacene thin films of different materials for gate insulators using atomic force microscope (AFM) and x-ray diffraction (XRD). The pentacene thin films are fabricated by evaporation on different polymer substrates. We used HMDS (Hexa Methyl Di Silazane), PVA (Poly Vinyl Alcohol) and PMMA (Poly Methyl Meth Acrylate) for the polymer substrates, on which pentacene is deposited at various substrate temperatures. The case of pentacene deposited on the PMMA has the largest grain size and least trap concentration. We also fabricated pentacene TFTs with the PMMA gate insulator. Pentacene TFTs with PMMA gate insulator, shows high field-effect mobility (ｕFET= 0.03 cm2/Vs) and large on/off current ratio (>105) and small threshold voltage (Vth= -6 V).

Crystal growth, characterization and dielectric studies of silica gel-grown polydistrontiumdimalate pentahydrate: a 2D porous metal-organic framework

2015 ◽  
Vol 38 (1-2) ◽  
Author(s):  
Remya M. Nair ◽  
Vijayamohanadas L. Siji ◽  
Velappan Nair S. Dhanya ◽  
Sunalya M. Roy ◽  
Maliyeckal R. Sudarsanakumar ◽  
...  
Keyword(s):  
Metal Organic Framework ◽  
Porous Metal ◽  
Sodium Metasilicate ◽  
Infrared Analysis ◽  
X Ray Diffraction ◽  
X Ray ◽  
Growth Characterization ◽  
Metal Organic ◽  
Gel Preparation ◽  
Organic Framework

AbstractGood-quality single crystals of polydistrontiumdimalatepentahydrate, a two-dimensional porous metal-organic framework, were successively grown by gel diffusion technique. Sodium metasilicate was used for gel preparation. Single crystal X-ray diffraction analyses showed that the compound crystallizes in triclinic space group P-1. The functional groups present in the crystals were identified by Fourier transform-infrared analysis. Elemental, powder X-ray diffraction and UV-visible spectral analyses of the compound were also performed. Thermal stability of the grown crystals was analyzed by thermogravimetry. Dielectric analyses of the title compound were conducted at room temperature in the frequency range of 400 Hz–4 MHz.

Processing of Biodegradable Polymer Composite Using Soy Protein-Based Resin and Nanoclay

2016 ◽  
Author(s):  
Mohammad K. Hossain ◽  
Samira N. Shaily ◽  
Hadiya J. Harrigan ◽  
Terrie Mickens
Keyword(s):  
Electron Microscopy ◽  
Mechanical Properties ◽  
Scanning Electron Microscopy ◽  
Optical Microscopy ◽  
Soy Protein ◽  
Poly Vinyl Alcohol ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Scanning Electron

A completely biodegradable composite was fabricated from an herbal polymer, soy protein concentrate (SPC) resin. Soy protein was modified by adding 30 wt% of glycerol and 5 wt% of poly vinyl alcohol (PVA) to enhance its mechanical as well as thermal property. 3%, 5%, 10%, and 20% nanoclay (NC) were infused into the system. To evaluate its mechanical properties, crystallinity, thermal properties, bonding interaction, and morphological evaluation, tensile, X-ray diffraction (XRD), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), and Fourier transform infrared spectroscopy (FTIR) tests, and optical microscopy (OM) and scanning electron microscopy (SEM) evaluation were performed. Tensile tests showed that the addition of nanoclay improved the mechanical properties of the modified resin. Soy protein is hydrophilic due to the presence of amino acids that contain various polar groups such as amine, carboxyl, and hydroxyl. As a result, polar nanoclay particles that are exfoliated can be evenly dispersed in the SPC resin. From experimental results, it is clear that adding of nanoclay with SPC resin significantly increased the stiffness of the SPC resin. A combination of 5% clay, 30% glycerol, and 5% PVA with the modified SPC resulted in the maximum stress of 18 MPa and Young modulus of 958 MPa. The modified SPC showed a reduced failure strain as well. X-ray diffraction curves showed an improvement of crystallinity of the prepared resin with increasing amount of nanoclay. Interaction among soy, glycerol, PVA, and nanoclay was clearly demonstrated from the FTIR analysis. Optical microscopy (OM) and scanning electron microscopy (SEM) micrographs revealed rougher surface in the nanoclay infused SPC samples compared to that of the neat one. SEM evaluation revealed rougher fracture surface in the NC infused samples.

Infrared Analysis of Renal Calculi: A Comparison with Conventional Techniques

1983 ◽  
Vol 20 (1) ◽  
pp. 20-25 ◽  
Author(s):  
Cathryn M Corns
Keyword(s):  
Diffraction Analysis ◽  
Renal Calculi ◽  
Complete Analysis ◽  
Infrared Analysis ◽  
X Ray Diffraction ◽  
X Ray ◽  
Calcium Magnesium ◽  
Combination Of Methods ◽  
Infrared Methods

The analysis of renal calculi is an oft-neglected corner of clinical biochemistry. This study compares results obtained by the conventional qualitative methods with results from quantitative and infrared methods and also investigates the role of x-ray diffraction analysis. Infrared spectroscopy, using a KBr disc technique, was found to be the single most useful method, being fast, simple to learn, using little sample, and in general permitting positive identification of most of the components found in renal calculi. A major advantage is that this method has approximately equal sensitivity for oxalate and phosphate, unlike the wet chemical methods. Infrared analysis is also useful in identifying the spurious materials sometimes submitted as renal calculi. X-ray diffraction analysis is not a technique that is routinely available, but it does provide information not given by other methods, eg, distinguishing Ca(COO)2·H2O from Ca(COO)2·2H2O. For complete analysis a combination of methods was adopted; carbonate is tested for using a microchemical technique, calcium, magnesium, and phosphate are quantitated by routine methods, and infrared analysis is used to detect oxalate and organic components. It must be emphasised that any method is only as good as the sample used, and different areas of the calculus must be analysed separately if useful results are to be obtained.

Synthesis and Properties of Poly(Vinyl Alcohol)/Calcium Aluminate Nanocomposites

1991 ◽  
Vol 245 ◽  
Author(s):  
Phillip B. Messersmith ◽  
Samuel I. Stupp
Keyword(s):  
Calcium Aluminate ◽  
Vinyl Alcohol ◽  
Organic Polymer ◽  
Poly Vinyl Alcohol ◽  
Structure And Properties ◽  
X Ray Diffraction ◽  
Layer Spacing ◽  
X Ray ◽  
New Class ◽  
Cementitious Systems

ABSTRACTThis paper describes the synthesis, structure and properties of a new layered nanocomposite which may have applications in cementitious systems. This material is one example of a new class of materials which consist of inorganic crystals containing intercalated organic polymer. The nanocomposite is synthesized by precipitating Ca2Al(OH)6[X]·nH2O (X=OH−, CO3−2) in the presence of poly(vinyl alcohol) (PVA). X-ray diffraction analysis indicates that the nanocomposite consists of calcium aluminate layers separated by interlayers containing anions, water and PVA. The intercalation of PVA can only be accomplished during crystal growth and is accompanied by an expansion in layer spacing from ˜8 Å to ˜18 Å. The nanocomposite exhibited enhanced thermal stability and when compacted into a cylinder was found to have more than twice the compressive strength than the pure calcium aluminate.

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