scholarly journals STUDY ON STRUCTURE AND CRYSTALLIZATION OF POLYPROPYLENE GRAFTED MALEIC ANHYDRIDE/NANOCLAY COMPOSITE

2017 ◽  
Vol 25 (1) ◽  
pp. 129-135
Author(s):  
Bui Chuong ◽  
Dang Viet Hung
Keyword(s):  
Maleic Anhydride ◽  
Crystalline Structure ◽  
Interlayer Space ◽  
Xrd Analysis ◽  
Microcrystalline Structure ◽  
Nonisothermal Crystallization ◽  
Polymer Part

Nanocomposite from polypropylene grafted maleic anhydride (PP-g-MA) and nanoclay were prepared by melt proccessing in Brabender extruder. XRD analysis shows the formation of nanostructure (intercalated and exfoliated) of nanocomposite with interlayer space (d-space) increasing from 26.3Å to 30.9Å. These structures, however, do not affect the microcrystalline structure of polymer part of nanocomposite in whole. The study on nonisothermal crystallization shows the development in 3-dimentional direction of crystallites, that means spherulite form of crystalline structure.

CHARACTERIZATION OF TAPIOCA STARCH PLASTICIZED BY 1-ETHYL-3-METHYLIMIDAZOLIUM ACETATE

2017 ◽  
Vol 79 (5-3) ◽  
Author(s):  
Shajaratuldur Ismail ◽  
Nurlidia Mansor ◽  
Zakaria Man ◽  
Khairun Azizi Azizli
Keyword(s):  
Thermal Degradation ◽  
Crystalline Structure ◽  
Xrd Analysis ◽  
Thermoplastic Starch ◽  
Thermal And Mechanical Properties ◽  
Materials Properties ◽  
Synthetic Materials ◽  
Water Ratio ◽  
Vital Parameters

Starch is one of natural materials that been used for producing biodegradable materials. The starch-based materials are produced through a process known as gelatinization with the presence of plasticizer and elevated temperature. Properties of starch-based materials are lacking in terms of viscosity, water absorption, thermal and mechanical properties compare with synthetic materials. Researchers are involved in finding ways for improvement of starch-based materials properties and one of that is introducing new plasticizer. 1-ethyl-3-methylimidazolium acetate, [Emim][OAc] is an ionic liquid that used as plasticizer to produce thermoplastic starch. Starch plasticized by [Emim][OAc] were prepared with different total plasticizer contents (50%,70%) and [Emim][OAc]/water ratio (1:6,1:4,2:3 wt%). The thermoplastic starches were characterized in terms of morphology, crystalline structure and thermal degradation. The results showed that 70% of total plasticizer contents were mixed well during gelatinization process. [Emim][OAc] contributed to granule disruption as shown by SEM. Based on the XRD analysis, it was shown that thermoplastic starch at 70% total plasticizer contents and 1:4 wt% ratio of [Emim][OAc]/water, caused disruption of the A-type crystalline structure, generated VH-type crystalline structure and thus increased the mobility of the amorphous starch. The presence of [Emim][OAc] promotes the thermal degradation of starch molecules as described by TGA. Therefore, plasticizer contents and [Emim][OAc]/water ratio are vital parameters that influences the properties of thermoplastic starch.

scholarly journals Enhancing the Thermal Stability of Ionogels: Synthesis and Properties of Triple Ionic Liquid/Halloysite/MCC Ionogels

Molecules ◽  
2021 ◽  
Vol 26 (20) ◽  
pp. 6198
Author(s):  
Olga V. Alekseeva ◽  
Valeriya D. Shibaeva ◽  
Andrew V. Noskov ◽  
Vladimir K. Ivanov ◽  
Alexander V. Agafonov
Keyword(s):  
Thermal Stability ◽  
Ionic Liquid ◽  
Glass Transition ◽  
Mechanical Characteristics ◽  
Interlayer Space ◽  
Xrd Analysis ◽  
Mechanical Tests ◽  
Water Molecules ◽  
Residual Water ◽  
Thermal Stability Of

In this study, an ionic liquid (IL), 1-butyl-3-methylimidazolium acetate, was used to prepare ionogels with microcrystalline cellulose (MCC) and halloysite (Hal). SEM, XRD, TG, DSC, FTIR spectroscopy, conductometry and mechanical tests were used to study the morphology, structure, thermal behaviour and electrophysical and mechanical characteristics of synthesised ionogels. XRD analysis showed a slight decrease in the interlayer space of halloysite in ionogels containing MCC, which may have been associated with the removal of residual water molecules resulting from hydrophilic IL anions and polymer macromolecules. A change in conductivity and glass-transition temperature of the ionic liquid was revealed due to intercalation into halloysite (a confinement effect) and modification with cellulose. For triple IL/Hal/MCC ionogels, the characteristic thermal degradation temperatures were higher than the corresponding values for IL/Hal composites. This indicates that the synthesised IL/Hal/MCC ionogels are characterised by a greater thermal stability than those of IL/Hal systems.

The adsorption of berberine by montmorillonite and thermo-XRD analysis of the organo-clay complex

Clay Minerals ◽  
2005 ◽  
Vol 40 (2) ◽  
pp. 223-232 ◽  
Author(s):  
E. Cohen ◽  
T. Joseph ◽  
I. Lapides ◽  
S. Yariv
Keyword(s):  
Thermal Treatment ◽  
Cation Exchange ◽  
Room Temperature ◽  
Interlayer Space ◽  
Divalent Cations ◽  
Xrd Analysis ◽  
Basal Spacing ◽  
Alumino Silicate ◽  
Silicate Layers ◽  
Heating Up

AbstractThe adsorption of the large cationic alkaloid berberine by montmorillonite in aqueous suspensions was investigated. An adsorption isotherm of berberine and desorption isotherms of exchangeable Na+, K+, Mg2+ and Ca2+ were determined by chemical analysis of the non-adsorbed berberine and the released cations in the supernatants. The isotherms suggest that the adsorption of berberine takes place in two different types of reaction mechanism: (1) cation exchange, and (2) a secondary organophyllic adsorption. The cation exchange occurring first is followed by the secondary adsorption which is accompanied by Cl- adsorption. Monovalent cations are exchanged before the divalent cations.Samples loaded with increasing amounts of berberine were examined by X-ray diffraction at room temperature, and after gradual heating up to 420°C. The basal spacing of the loaded samples after the thermal treatment became 1.28 nm, indicating the formation of carbon in the interlayer, thus proving that the adsorbed berberine was located in the interlayer space. At room temperature the basal spacing of samples loaded with 8 and 15 mmol of berberine per 100 g of clay was 1.28–1.30 nm indicating that in the interlayer space berberine cations were lying parallel to the alumino-silicate layers. The basal spacing of a sample with 36 mmol of berberine per 100 g of clay was 1.48 nm. This spacing does not give conclusive information on the arrangement of berberine in the interlayer. The spacing of samples with 57–147 mmol of berberine per 100 g of clay was 1.59 nm, suggesting the presence of bilayers of berberine in the interlayers. During thermal dehydration, the spacing of samples with 36–73 mmol of berberine per 100 g of clay decreased, but that of samples with 105–147 mmol of berberine per 100 g of clay increased to 1.66 nm. These samples contain organophilic adsorbed berberine and it is suggested that due to the thermal treatment berberine was tilted relative to the TOT lamellae, with anhydrous Cl- between the berberine cations.

The Structure and Property of Akund

2019 ◽  
Vol 793 ◽  
pp. 59-63
Author(s):  
Wei Dong Li ◽  
Xuan Li ◽  
Ming Hui Xu
Keyword(s):  
Mechanical Properties ◽  
Moisture Content ◽  
Thermal Behavior ◽  
Crystalline Structure ◽  
Xrd Analysis ◽  
Cotton Fibers ◽  
Moisture Regain ◽  
Structure And Property ◽  
Ft Ir

The morphology, microfiber structure, crystalline structure, mechanical properties and thermal behavior of the Akund were studied with SEM, FT-IR, TG and XRD analysis, and compared with cotton fibers. Its mechanical properties, moisture content and moisture regain were tested, and its solubility was analyzed in different solutions.

CdS Nanostructured Thin Films Synthesized by Pulsed Laser Deposition for Solar Cell Technology

2021 ◽  
Vol 882 ◽  
pp. 155-164
Author(s):  
Jinan A. Abd ◽  
Wasan M. Mohammed ◽  
Amer Al-Nafiey
Keyword(s):  
Thin Films ◽  
Optical Properties ◽  
Solar Cell ◽  
Pulsed Laser Deposition ◽  
Crystalline Structure ◽  
Pulsed Laser ◽  
Laser Pulses ◽  
Xrd Analysis ◽  
Laser Deposition ◽  
Cds Thin Films

CdS thin films have been grown on glass substrate at 250o C employing pulsed laser deposition method. The effect of laser pulses number on the crystalline structure, surface morphology, optical properties, and films thickness have been studied. XRD analysis shows that the CdS films have polycrystalline and hexagonal nanostructure with three notable peaks along (100), (002), and (101) planes and preferentially orientated along (101). The crystallite size of the preferred orientation was in the range of (21.4 - 27.3 nm). With small pulses number, XRD pattern confirms the formation of CdO with three peaks (111), (200), and (220). Theses peaks gradually reduce with the increasing of the pulses. The absorbance of the films is in the visible part of the spectrum. The band gap of the synthesized films reduces by rising the number of laser pulses. AFM studies indicate that the grain size and surface roughness increase with the film thickness. Due to the good crystalline structure and optical properties of the film of the highest thickness, it has been grown on a wafer silicon substrate for solar cell applications measurements. Hall measurements indicate low resistivity of 0.3×10-2 (Ω.m) and high conductivity of 3.3×10+2 (Ω.m)-1. The efficiency of the n-CdS/ p-Si junction has been calculated to be 3.4 % using I-V characteristic measurement. Keywords: pulsed laser, thin films, structural, optical, morphology, solar cell measurements

Microstructure of Rapidly Solidified Melt-Spun Ribbon in AlCoCrFeNi2.1 Eutectic High-Entropy Alloys

2016 ◽  
Vol 879 ◽  
pp. 1350-1354 ◽  
Author(s):  
Takeshi Nagase ◽  
Mamoru Takemura ◽  
Mitsuaki Matsumuro
Keyword(s):  
Grain Boundary ◽  
Rapid Solidification ◽  
Crystalline Structure ◽  
Xrd Analysis ◽  
Solidification Structure ◽  
High Entropy Alloys ◽  
High Entropy ◽  
Melt Spun ◽  
Melt Spun Ribbons ◽  
Rapidly Solidified

The microstructure of rapidly solidified melt-spun ribbon in AlCoCrFeNi2.1 eutectic high entropy alloys (EHEAs) was investigated for clarifying the effect of rapid solidification on the constituent phases and microstructure of specimens formed through solidification. XRD analysis indicates that the melt-spun ribbons were composed of a mixture of fcc and bcc phases. The rapidly solidified melt-spun ribbon shows a fine poly-crystalline structure with fcc matrix phase and crystalline precipitates in the grain boundary, indicating that the solidification structure in the melt-spun ribbon was significantly different from that obtained by conventional casting processes.

X-Ray Diffraction and Microstructure Analysis of EN47 Spring Steel at Various Soaking Period of Time

2019 ◽  
Vol 969 ◽  
pp. 104-109
Author(s):  
S. Ramesh Kumar ◽  
S. Senthil Kumaran ◽  
G. Ramesh ◽  
M. Sree Arravind ◽  
D. Venkateswarlu
Keyword(s):  
Crystalline Structure ◽  
Interatomic Distance ◽  
Xrd Analysis ◽  
Sem Analysis ◽  
Spring Steel ◽  
Morphological Properties ◽  
X Ray Diffraction ◽  
Interatomic Distances ◽  
Soaking Time ◽  
X Ray

The study presents the results of the investigation on the effect of soaking time on the, Crystalline structure and morphological properties of annealed EN-47 Spring Steel. The EN-47 Spring Steel samples were heated at 860 °C for soaking times of 60, 120, 240, 480 minutes. SEM analysis and XRD analysis were carried out to determine the morphology and crystalline phase of the material with increasing soaking time. Interatomic Distances also decreased with increased in soaking time. The sample with the Soaking time of 480 minutes exhibits a higher Interatomic Distance because of Formation of bigger grains. Through X-ray Diffraction transformation of the crystalline structure were analyzed, in that it is observed that Iron did not undergo any crystalline structure transformation with respect to soaking time whereas other elements changed their structure. Keywords: EN-47, Annealing, XRD, Crystalline Structure, SEM.

Sol Gel Synthesis and In Vitro Evaluation of Apatite Forming Ability of Silica-Based Composite Glass in SBF

2015 ◽  
Vol 660 ◽  
pp. 125-131 ◽  
Author(s):  
S.A. Syed Nuzul Fadzli ◽  
S. Roslinda ◽  
Firuz Zainuddin
Keyword(s):  
Crystalline Structure ◽  
Sol Gel ◽  
Xrd Analysis ◽  
Carbonate Apatite ◽  
Ftir Analysis ◽  
Apatite Structure ◽  
Composite Glass ◽  
Sbf Solution ◽  
Sol Gel Synthesis

In this study, xerogel glass based on SiO-CaO-PO4 was synthesized by a low temperature acid catalysed sol-gel route. The in vitro evaluation of apatite forming ability for the glass was conducted in simulated body fluid (SBF) solution as the glasses were immersed for duration of 1, 7, 24 hours and 7 days. The XRD analysis showed that the glass formed semi-crystalline structure when sintered at 1000oC and consisted of Ca2O7P2 and Ca2O4Si phases. Image captured using FESEM showed the apatite-like structures were eventually formed on the glass top surface in small numbers after the glass immersed in SBF for only an hour. The numbers of the apatite structures were continuously grown with the increase period of immersion time. The apatite structure mostly covered on top of the glass surface after 24 hours of immersion and continuously growth into bone-like apatite structure when immersed for 7 days in the SBF. The apatite layer formed on the surface of the glass was confirmed as crystalline structure of hydroxyl-carbonate-apatite (HCA) as revealed by the complimentary results of EDS, XRD and FTIR analysis.

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