Thermal Effect of Ceramic Nanofiller Aluminium Nitride on Polyethylene Properties

Ethylene polymerization was done to form polyethylene nano-composite with nanoaluminum nitride using zirconocene catalysts. Results show that the catalytic activity is maximum at a filler loading of 15 mg nanoaluminum nitride. Differential scanning calorimeter (DSC) and X-ray diffraction (XRD) results show that percentage crystallinity was also marginally higher at this amount of filler. Thermal behavior of polyethylene nanocomposites (0, 15, 30, and 45) mg was studied by DSC and thermal gravimetric analyzer (TGA). Morphology of the component with 15 mg aluminium nitride is more fibrous as compared to 0 mg aluminium nitride and higher filler loading as shown by SEM images. In order to understand combustibility behavior, tests were performed on microcalorimeter. Its results showed decrease in combustibility in polyethylene nanocomposites as the filler loading increases.

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Effect of Immobilization Methods on the Production of Polyethylene-cellulose Biocomposites via Ethylene Polymerization with Metallocene/MAO Catalyst

BULLETIN OF CHEMICAL REACTION ENGINEERING AND CATALYSIS ◽

10.9767/bcrec.15.3.8735.752-764 ◽

2020 ◽

Vol 15 (3) ◽

pp. 752-764

Author(s):

Praonapa Tumawong ◽

Ekrachan Chaichana ◽

Bunjerd Jongsomjit

Keyword(s):

Catalytic Activity ◽

Ethylene Polymerization ◽

Heterogeneous System ◽

Metallocene Catalyst ◽

Homogeneous System ◽

Gravimetric Analysis ◽

Thermal Gravimetric ◽

Active Components ◽

Scanning Calorimetry ◽

X Ray

Polyethylene-cellulose biocomposites were synthesized here via the ethylene polymerization with metallocene as a catalyst along with methylaluminoxane (MAO) as a cocatalyst. The immobilization method in which the catalyst or cocatalyst is fixed onto the catalytic filler (cellulose) can be classified into 3 methods according to the active components fixed onto the filler surface: 1) only metallocene catalyst (Cellulose/Zr), 2) only MAO cocatalyst (Cellulose/MAO) and 3) mixture of metallocene and MAO (Cellulose/(Zr+MAO)). It was found that the different immobilization methods or different fillers altered the properties of the obtained composites and also the catalytic activity of the polymerization systems. It was found that Cellulose/MAO provided the highest catalytic activity among all fillers due to a crown-alumoxane complex, which caused the heterogeneous system with this filler behaved similarly to the homogeneous system. The different fillers also produced the biocomposites with some different properties such as crystallinity which Cellulose/Zr provided the highest crystallinity compared with other fillers as observed by a thermal gravimetric analysis-differential scanning calorimetry (TGA-DSC). Nevertheless, the main crystal structure indicated to the typical polyethylene was still observed for all obtained biocomposites with different fillers as observed by an X-ray diffractometer (XRD). Copyright © 2020 BCREC Group. All rights reserved

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Evaluation of LDPE Degradation Under Controlled Composting

Nature Environment and Pollution Technology ◽

10.46488/nept.2021.v20i03.041 ◽

2021 ◽

Vol 20 (3) ◽

Author(s):

S. Singh ◽

S. Shankar ◽

Shikha .

Keyword(s):

Major Change ◽

Natural Ecosystem ◽

Gravimetric Analysis ◽

Thermal Gravimetric ◽

X Ray Diffraction ◽

Scanning Calorimetry ◽

Sem Images ◽

X Ray ◽

Polyethylene Films ◽

Scanning Electron

The compost burial test was performed to determine the degradation of commercially available low-density polyethylene in natural compost for a period of six months. Biodegradability of polyethylene films in compost was monitored using scanning electron microscopy (SEM), Energy dispersive X-Ray, Fourier transform infrared spectroscopy (FTIR), X-Ray diffraction (XRD), thermal gravimetric analysis (TGA), differential scanning calorimetry (DSC), and weight reduction analysis. After six months of compost exposure, a major change over the surface of LDPE was observed. SEM images clearly showed the exfoliation and cracks on the film leading to degradation. The other analysis also showed a change in the thermal properties and crystallinity of the LDPE films. The composting method could prove to be the reliable and ecological method of degrading plastic waste without hindering the natural ecosystem.

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Bis(μ-carboxylato)dienerhodium(I) Complexes - Synthesis, Characterization and Catalytic Activity

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc20081205 ◽

2008 ◽

Vol 73 (8-9) ◽

pp. 1205-1221 ◽

Cited By ~ 4

Author(s):

Jiří Zedník ◽

Jan Sedláček ◽

Jan Svoboda ◽

Jiří Vohlídal ◽

Dmitrij Bondarev ◽

...

Keyword(s):

Catalytic Activity ◽

Diffraction Analysis ◽

Spectroscopic Methods ◽

X Ray Diffraction ◽

X Ray

Dinuclear rhodium(I) η2:η2-cycloocta-1,5-diene (series a) and η2:η2-norborna-2,5-diene (series b) complexes with μ-RCOO- ligands, where R is linear C21H43 (complexes 1a, 1b), CH2CMe3 (2a, 2b), 1-adamantyl (3a, 3b) and benzyl (4a, 4b), have been prepared and characterized by spectroscopic methods. Structures of complexes 2b, 3a and 4a were determined by X-ray diffraction analysis. Complexes prepared show low to moderate catalytic activity in polymerization of phenylacetylene in THF giving high-cis-transoid polymers, but they show only oligomerization activity in dichloromethane.

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Hydrochloric Acid Modification and Lead Removal Studies on Naturally Occurring Zeolites from Nevada, New Mexico, and Arizona

Processes ◽

10.3390/pr9071238 ◽

2021 ◽

Vol 9 (7) ◽

pp. 1238

Author(s):

Garven M. Huntley ◽

Rudy L. Luck ◽

Michael E. Mullins ◽

Nick K. Newberry

Keyword(s):

New Mexico ◽

Surface Area ◽

Bet Surface Area ◽

Lead Removal ◽

X Ray Diffraction ◽

Sem Images ◽

X Ray ◽

Naturally Occurring ◽

27Al Mas Nmr ◽

Modified Zeolites

Four naturally occurring zeolites were examined to verify their assignments as chabazites AZLB-Ca and AZLB-Na (Bowie, Arizona) and clinoptilolites NM-Ca (Winston, New Mexico) and NV-Na (Ash Meadows, Nevada). Based on powder X-ray diffraction, NM-Ca was discovered to be mostly quartz with some clinoptilolite residues. Treatment with concentrated HCl (12.1 M) acid resulted in AZLB-Ca and AZLB-Na, the chabazite-like species, becoming amorphous, as confirmed by powder X-ray diffraction. In contrast, NM-Ca and NV-Na, which are clinoptilolite-like species, withstood boiling in concentrated HCl acid. This treatment removes calcium, magnesium, sodium, potassium, aluminum, and iron atoms or ions from the framework while leaving the silicon framework intact as confirmed via X-ray fluorescence and diffraction. SEM images on calcined and HCl treated NV-Na were obtained. BET surface area analysis confirmed an increase in surface area for the two zeolites after treatment, NM-Ca 20.0(1) to 111(4) m2/g and NV-Na 19.0(4) to 158(7) m2/g. 29Si and 27Al MAS NMR were performed on the natural and treated NV-Na zeolite, and the data for the natural NV-Na zeolite suggested a Si:Al ratio of 4.33 similar to that determined by X-Ray fluorescence of 4.55. Removal of lead ions from solution decreased from the native NM-Ca, 0.27(14), NV-Na, 1.50(17) meq/g compared to the modified zeolites, 30 min HCl treated NM-Ca 0.06(9) and NV-Na, 0.41(23) meq/g, and also decreased upon K+ ion pretreatment in the HCl modified zeolites.

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Electrospun Membranes Based on Polycaprolactone, Nano-Hydroxyapatite and Metronidazole

Materials ◽

10.3390/ma14040931 ◽

2021 ◽

Vol 14 (4) ◽

pp. 931

Author(s):

Ioana-Codruţa Mirică ◽

Gabriel Furtos ◽

Ondine Lucaciu ◽

Petru Pascuta ◽

Mihaela Vlassa ◽

...

Keyword(s):

Fiber Diameter ◽

Maximum Load ◽

Guided Bone Regeneration ◽

Attenuated Total Reflectance ◽

X Ray Diffraction ◽

Sem Images ◽

Total Reflectance ◽

X Ray ◽

Electrospun Membranes

The aim of this research was to develop new electrospun membranes (EMs) based on polycaprolactone (PCL) with or without metronidazole (MET)/nano-hydroxyapatite (nHAP) content. New nHAP with a mean diameter of 34 nm in length was synthesized. X-ray diffraction (XRD) and attenuated total reflectance Fourier transform infrared spectroscopy (FTIR-ATR) were used for structural characterization of precursors and EMs. The highest mechanical properties (the force at maximum load, Young’s modulus and tensile strength) were found for the PCL membranes, and these properties decreased for the other samples in the following order: 95% PCL + 5% nHAP > 80% PCL + 20% MET > 75% PCL + 5% nHAP + 20% MET. The stiffness increased with the addition of 5 wt.% nHAP. The SEM images of EMs showed randomly oriented bead-free fibers that generated a porous structure with interconnected macropores. The fiber diameter showed values between 2 and 16 µm. The fiber diameter increased with the addition of nHAP filler and decreased when MET was added. New EMs with nHAP and MET could be promising materials for guided bone regeneration or tissue engineering.

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Synthesis and catalytic activity of homoleptic lanthanide-tris(cyclopropylethinyl)amidinates

New Journal of Chemistry ◽

10.1039/c5nj00555h ◽

2015 ◽

Vol 39 (10) ◽

pp. 7595-7601 ◽

Cited By ~ 12

Author(s):

Farid M. Sroor ◽

Cristian G. Hrib ◽

Liane Hilfert ◽

Sabine Busse ◽

Frank T. Edelmann

Keyword(s):

Crystal Structure ◽

Catalytic Activity ◽

X Ray Diffraction ◽

X Ray ◽

Type C

New unsolvated, homoleptic lanthanide(iii) tris(cyclopropylethinylamidinate) complexes of the type [c-C3H5–CC–C(NR)2]3Ln (R = iPr, cyclohexyl; Ln = Nd, Sm, Ho) have been prepared and the crystal structure of the holmium derivative [c-C3H5–CC–C(NiPr)2]3Ho has been confirmed by X-ray diffraction.

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STRUCTURAL AND ELECTROCHEMICAL PROPERTIES OF THIN LAYERS OF BINARY Ni–Fe ALLOYS ELECTRODEPOSITED BY TWO DIFFERENT BATHS: ACID AND IONIC LIQUID

Surface Review and Letters ◽

10.1142/s0218625x19500252 ◽

2018 ◽

Vol 25 (08) ◽

pp. 1950025

Author(s):

RAFIK MAIZI ◽

ATHMANE MEDDOUR ◽

CÉLINE ROUSSE

Keyword(s):

Ionic Liquid ◽

Nickel Content ◽

Deposition Potential ◽

Thin Layers ◽

X Ray Diffraction ◽

Sem Images ◽

X Ray ◽

Different Shapes ◽

Fe Alloys ◽

Irregular Behavior

The deposition of Ni–Fe thin layers in boric acid and ionic liquid ([BuMePyr][Tf2N]) baths were successfully prepared. The obtained materials have been characterized by X-ray diffraction (XRD), Energy Dispersive X-ray spectroscopy (EDX) and SEM. Meanwhile, these materials were carried out by chronoamperometry or chronopotentiometry by varying the intensity of the current and the deposition potential. The results indicate that the coatings of Ni–Fe alloys were successfully obtained by electroplating on the copper substrates, and the alloys composition shows irregular behavior with polarization. The nickel content in the samples is in the range of 55–90%, but the iron content ranges from 10–30%, when potential deposits were varied from [Formula: see text]2[Formula: see text]V to [Formula: see text]4[Formula: see text]V vs Ni electrode. The results also showed that the thin layers are monophased; they contain the Ni3Fe phase. Further, SEM images of Ni–Fe alloys show the different shapes of particles.

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A Facile Method to Construct MXene/CuO Nanocomposite with Enhanced Catalytic Activity of CuO on Thermal Decomposition of Ammonium Perchlorate

Materials ◽

10.3390/ma11122457 ◽

2018 ◽

Vol 11 (12) ◽

pp. 2457 ◽

Cited By ~ 6

Author(s):

Haifeng Zhao ◽

Jing Lv ◽

Junshan Sang ◽

Li Zhu ◽

Peng Zheng ◽

...

Keyword(s):

Thermal Decomposition ◽

Catalytic Activity ◽

Ammonium Perchlorate ◽

Photoelectron Spectra ◽

Gravimetric Analysis ◽

X Ray Diffraction ◽

Scanning Calorimetry ◽

X Ray ◽

Improved Performance ◽

Calcination Method

In this work, a mixing-calcination method was developed to facilely construct MXene/CuO nanocomposite. CuO and MXene were first dispersed in ethanol with sufficient mixing. After solvent evaporation, the dried mixture was calcinated under argon to produce a MXene/CuO nanocomposite. As characterized by X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM), and X-ray photoelectron spectra (XPS), CuO nanoparticles (60–100 nm) were uniformly distributed on the surface and edge of MXene nanosheets. Furthermore, as evaluated by differential scanning calorimetry (DSC) and thermal gravimetric analysis (TGA), the high-temperature decomposition (HTD) temperature decrease of ammonium perchlorate (AP) upon addition of 1 wt% CuO (hybridized with 1 wt% MXene) was comparable with that of 2 wt% CuO alone, suggesting an enhanced catalytic activity of CuO on thermal decomposition of AP upon hybridization with MXene nanosheets. This strategy could be further applied to construct other MXene/transition metal oxide (MXene/TMO) composites with improved performance for various applications.

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Influence of pretreatment on the properties of α-Fe2O3 and the effect on photocatalytic degradation of methylene blue under visible light

Water Science & Technology ◽

10.2166/wst.2020.506 ◽

2020 ◽

Vol 82 (11) ◽

pp. 2415-2424

Author(s):

S. Mokhtari ◽

N. Dokhan ◽

S. Omeiri ◽

B. Berkane ◽

M. Trari

Keyword(s):

Methylene Blue ◽

Average Crystallite Size ◽

Sample Surface ◽

X Ray Diffraction ◽

Sem Images ◽

X Ray ◽

Lattice Constants ◽

Electrochemical Pretreatment ◽

Crystal Properties ◽

Rhombohedral Symmetry

Abstract The hematite (α-Fe2O3) nanostructures were synthesized by thermal oxidation of metal at 500 °C under atmospheric pressure. We studied the effect of the electrochemical pretreatment of the substrate before calcinations and its impact on the morphology, crystalline structure, lattice microstructural, and optical properties of α-Fe2O3. Uniform nanosheets were observed on the sample surface after calcination; their dimension and morphology were accentuated by the pretreatment, as confirmed by the SEM images. The characteristics of the nanostructures, analyzed by X-ray diffraction (XRD), revealed a rhombohedral symmetry with the space group R-3c and lattice constants: a = 0.5034 nm and c = 1.375 nm. The average crystallite size and strain, determined from the Williamson-Hall (W-H) plot, showed substantial variations after the substrate pretreatment. The Raman spectroscopy confirmed the changes in the crystal properties of the hematite submitted to pretreatment. The diffuse reflectance allowed to evaluate the optical gap which lies between 1.2 and 1.97 eV, induced by the electrochemical processing. The photocatalytic activity of α-Fe2O3 films was assessed by the degradation of methylene blue (MB) under LED light; 15% enhancement of the degradation for the pretreated specimens was noticed.

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Synthesis, Characterization, and Crystal Structure of Several Novel Acidic Ionic Liquids: 1-ethyl-2-alkyl-benzimidazolium Tetra-Fluoroborate

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.457-458.139 ◽

2013 ◽

Vol 457-458 ◽

pp. 139-143 ◽

Cited By ~ 1

Author(s):

Ming Tian Wang ◽

Chang Ping Pan ◽

Wei Peng Gai ◽

Xiao Xia Lv ◽

Min Gang Zhai ◽

...

Keyword(s):

Crystal Structure ◽

Ionic Liquid ◽

Acetic Acid ◽

Catalytic Activity ◽

Lamellar Structure ◽

X Ray Diffraction ◽

X Ray ◽

Acidic Ionic Liquid ◽

Acidic Ionic Liquids ◽

Good Catalytic Activity

A series of novel acidic ionic liquid: 1-ethyl-2-alkyl-benzimidazolium tetra-fluoroborate (alkyl= Et, Pr-n, Bu-n) were prepared by simple acid-based neutralization of 1-ethyl-2-alkyl-benzimidazole and tetrafluoroboric acid. The compounds were characterized by FTIR spectra, elemental analysis,1HNMR spectra and thermogravimetric analysis. These novel tetra-fluoroborate salts show good catalytic activity to esterification of benzyl alcohol and acetic acid. Furthermore, a crystal of ([H-ebBiBF4) was prepared with the crystal structure and determined by X-ray diffraction analysis. The molecular is of lamellar structure as mainly π electron ring is stacked interleaving between two layers. The results of cation and anion arranged orderly in pair indicate that the coulombic attraction is more dominant. Simultaneously, the weak local hydrogen bonds C-H···F exist in the molecules.

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