Isolation and Characterization of 1,3-Bis(vinylbenzyl)thymine: Copolymerization with Vinylbenzyl Thymine Ammonium Chloride

A novel bioinspired molecule, 1,3-bis(vinylbenzyl)thymine (bisVBT), was isolated as a by-product during the synthesis of 1-(4-vinylbenzyl)thymine (VBT) and analyzed with various techniques: NMR, IR, and Single-Crystal X-ray Diffraction. In addition to embodying all the desired characteristics of VBT (i.e., having the ability to undergo a 2π+2π photodimerization reaction upon UV irradiation, a derivatization site, hydrogen bonding sites, and aromatic stacking ability) the bisVBT monomer has the added benefit of having two vinyl groups for cross-polymerization. Copolymerizing the bisVBT monomer with the charged monomer vinylbenzyl triethylammonium (VBA) chloride, different copolymers/terpolymers/cross-linked network were obtained, as it was shown by the absence of the vinyl resonance in the NMR spectra. Thermal Gravimetric Analysis (TGA) and Differential Scanning Calorimetry (DSC) showed an indication of materials with low degree of cross-linking. A Gel Permeation Chromatography (GPC) method was improved to better characterize the molecular weight distributions of the cationic structures. Preliminary qualitative cross-linking studies were performed on bisVBT-VBA copolymers, and a comparison with VBT-VBA copolymers is presented.

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Synthesis and Characterization of N-Substituted Polyether-Block-Amide Copolymers

Materials ◽

10.3390/ma14040773 ◽

2021 ◽

Vol 14 (4) ◽

pp. 773

Author(s):

Jyun-Yan Ye ◽

Kuo-Fu Peng ◽

Yu-Ning Zhang ◽

Szu-Yuan Huang ◽

Mong Liang

Keyword(s):

Titanium Isopropoxide ◽

Decomposition Temperature ◽

Phenyl Isocyanate ◽

Cross Linking ◽

Resonance Spectroscopy ◽

X Ray Diffraction ◽

Scanning Calorimetry ◽

Degradation Temperature ◽

Melt Polycondensation ◽

Structural Regularity

A series of N-substituted polyether-block-amide (PEBA-X%) copolymers were prepared by melt polycondensation of nylon-6 prepolymer and polytetramethylene ether glycol at an elevated temperature using titanium isopropoxide as a catalyst. The structure, thermal properties, and crystallinity of PEBA-X% were investigated using nuclear magnetic resonance spectroscopy, Fourier-transform infrared spectroscopy, differential scanning calorimetry, wide angle X-ray diffraction, and thermogravimetric analysis. In general, the crystallinity, melting point, and thermal degradation temperature of PEBA-X% decreased as the incorporation of N-methyl functionalized groups increased, owing to the disruption caused to the structural regularity of the copolymer. However, in N-acetyl functionalized analogues, the crystallinity first dropped and then increased because of a new γ form arrangement that developed in the microstructure. After the cross-linking reaction of the N-methyl-substituted derivative, which has electron-donating characteristics, with poly(4,4′-methylenebis(phenyl isocyanate), the decomposition temperature of the resulting polymer significantly increased, whereas no such improvements could be observed in the case of the electro-withdrawing N-acetyl-substituted derivative, because of the incompleteness of its cross-linking reaction.

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Synthesis, characterization and corrosion protection properties of polyN-(p-bromophenyl)-2-methacrylamide-co-glycidyl methacrylate on low nickel stainless steel

Journal of Polymer Engineering ◽

10.1515/polyeng.2011.042 ◽

2011 ◽

Vol 31 (2-3) ◽

Cited By ~ 2

Author(s):

Sakvai Mohammed Safiullah ◽

Deivasigamani Thirumoolan ◽

Kottur Anver Basha ◽

K. Mani Govindaraju ◽

Dhanraj Gopi ◽

...

Keyword(s):

Stainless Steel ◽

Corrosion Protection ◽

Glycidyl Methacrylate ◽

Electrochemical Impedance ◽

Thermo Gravimetric Analysis ◽

Gel Permeation Chromatography ◽

Gravimetric Analysis ◽

Scanning Calorimetry ◽

Protection Efficiency ◽

Ft Ir

Abstract The synthesis of copolymers from different feed ratios of N-(p-bromophenyl)-2- methacrylamide (PBPMA) and glycidyl methacrylate (GMA) was achieved by using free radical solution polymerization technique and characterized using FT-IR, 1H and 13C NMR spectroscopy. The thermal stability of the synthesized copolymers was studied using thermo-gravimetric analysis (TGA) and differential scanning calorimetry (DSC). The molecular weight of the copolymer is determined by gel permeation chromatography (GPC). The corrosion performances of low nickel stainless steel specimens dip coated with different composition of copolymers were investigated in 0.5 M H2SO4 using potentiodynamic polarization and electrochemical impedance spectroscopic (EIS) techniques. The polarization and impedance measurements showed different corrosion protection efficiency with change in composition of the copolymers. It was found that the corrosion protection properties are owing to the barrier effect of the polymer layer covered on the low nickel stainless steel surfaces. However, it is observed that the mole ratio of PBPMA and GMA plays a major role in the protective nature of the copolymer.

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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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Development and In-Vitro Evaluation of pH Responsive Polymeric Nano Hydrogel Carrier System for Gastro-Protective Delivery of Naproxen Sodium

Advances in Polymer Technology ◽

10.1155/2019/6090965 ◽

2019 ◽

Vol 2019 ◽

pp. 1-13

Author(s):

Rai Muhammad Sarfraz ◽

Muhammad Rouf Akram ◽

Muhammad Rizwan Ali ◽

Asif Mahmood ◽

Muhammad Usman Khan ◽

...

Keyword(s):

Drug Release ◽

Naproxen Sodium ◽

Research Work ◽

Entrapment Efficiency ◽

Gravimetric Analysis ◽

X Ray Diffraction ◽

Scanning Calorimetry ◽

Swelling Behaviour ◽

X Ray

Current research work was carried out for gastro-protective delivery of naproxen sodium. Polyethylene glycol-g-poly (methacrylic acid) nanogels was developed through free radical polymerization technique. Formulation was characterized for swelling behaviour, entrapment efficiency, Fourier transform infrared (FTIR) spectroscopy, Differential scanning calorimetry (DSC), and Thermal Gravimetric Analysis (TGA), Powder X-ray diffraction (PXRD), Zeta size distribution, and Zeta potential measurements, and in-vitro drug release. pH dependent swelling was observed with maximum drug release at higher pH. PXRD studies confirmed the conversion of loaded drug from crystalline to amorphous form while Zeta size measurement showed size reduction. On the basis of these results it was concluded that prepared nanogels proved an effective tool for gastro-protective delivery of naproxen sodium.

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The Influence of Calcination Temperature on Quantitative Phase of Hematite from Iron Stone Tanah Laut

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1112.489 ◽

2015 ◽

Vol 1112 ◽

pp. 489-492

Author(s):

Ali Mufid ◽

M. Zainuri

Keyword(s):

Particle Size ◽

Calcination Temperature ◽

Thermo Gravimetric Analysis ◽

Precipitation Method ◽

Gravimetric Analysis ◽

X Ray Diffraction ◽

Scanning Calorimetry ◽

X Ray ◽

Particle Size Analyzer ◽

Co Precipitation

This research aims to form particles of hematite (α-Fe2O3) with a basis of mineral iron ore Fe3O4 from Tanah Laut. Magnetite Fe3O4 was synthesized using co-precipitation method. Further characterization using X-ray fluorescence (XRF) to obtain the percentage of the elements, obtained an iron content of 98.51%. Then characterized using thermo-gravimetric analysis and differential scanning calorimetry (TGA-DSC) to determine the calcination temperature, that at a temperature of 445 °C mass decreased by 0.369% due to increase in temperature. Further Characterization of X-ray diffraction (XRD) to determine the phases formed at the calcination temperature variation of 400 °C, 445 °C, 500 °C and 600 °C with a holding time of 5 hours to form a single phase α-Fe2O3 hematite. Testing with a particle size analyzer (PSA) to determine the particle size distribution, where test results indicate that the α-Fe2O3 phase of each having a particle size of 269.7 nm, 332.2 nm, 357.9 nm, 412.2 nm. The best quantity is shown at a temperature of 500 °C to form the hematite phase. This result is used as the calcination procedure to obtain a source of Fe ions in the manufacture of Lithium Ferro Phosphate.

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Effect of Sr2TiMnO6 fillers on mechanical, dielectric and thermal behaviour of PMMA polymer

Journal of Advanced Dielectrics ◽

10.1142/s2010135x15500186 ◽

2015 ◽

Vol 05 (03) ◽

pp. 1550018 ◽

Cited By ~ 13

Author(s):

P. Thomas ◽

B. S. Dakshayini ◽

H. S. Kushwaha ◽

Rahul Vaish

Keyword(s):

Coefficient Of Thermal Expansion ◽

Thermo Gravimetric Analysis ◽

Mechanical Analysis ◽

Gravimetric Analysis ◽

X Ray Diffraction ◽

Scanning Calorimetry ◽

Melt Mixing ◽

Transition Formula ◽

Thermal Stability Of ◽

Pmma Polymer

Composites of poly(methyl methacrylate) (PMMA) and [Formula: see text] (STMO) were fabricated via melt mixing followed by hot pressing technique. These were characterized using X-ray diffraction (XRD), thermo gravimetric analysis (TGA), differential scanning calorimetry (DSC), thermo mechanical analysis (TMA) and impedance analyser for their structural, thermal and dielectric properties. The coefficient of thermal expansion (CTE) was measured between 40°C and 100°C for pure PMMA is 115.2 ppm/°C, which was decreased to 78.58 ppm/°C when the STMO content was increased to 50 wt.% in PMMA. There was no difference in the glass transition ([Formula: see text]) temperature of the PMMA polymer and their composites. However, the FTIR analysis indicated possible interaction between the PMMA and STMO. The density and the hardness were increased as the STMO content increased in the PMMA matrix. Permittivity was found to be as high as 30.9 at 100 Hz for the PMMA+STMO-50 wt.% composites, indicating the possibility of using these materials for capacitor applications. The thermal stability of polymer was enhanced by incorporation of STMO fillers.

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Lipase mediated synthesis of polycaprolactone and its silica nanohybrid

Pure and Applied Chemistry ◽

10.1515/pac-2018-1011 ◽

2019 ◽

Vol 91 (6) ◽

pp. 957-965

Author(s):

Meltem Akkulak ◽

Yasemin Kaptan ◽

Yasar Andelib Aydin ◽

Yuksel Avcibasi Guvenilir

Keyword(s):

Average Molecular Weight ◽

Proton Nuclear Magnetic Resonance ◽

Gravimetric Analysis ◽

X Ray Diffraction ◽

Scanning Calorimetry ◽

Structural Investigations ◽

Crystallinity Degree ◽

Molecular Weights ◽

H Nmr

Abstract In this study, rice husk ash (RHA) silanized with 3-glycidyloxypropyl trimethoxysilane was used as support material to immobilize Candida antarctica lipase B. The developed biocatalyst was then utilized in the ring opening polymerization (ROP) of ε-caprolactone and in situ development of PCL/Silica nanohybrid. The silanization degree of RHA was determined as 4 % (w) by thermal gravimetric analysis (TGA). Structural investigations and calculation of molecular weights of nanohybrids were realized by proton nuclear magnetic resonance (1H NMR). Crystallinity was determined by differential scanning calorimetry (DSC) and X-ray diffraction (XRD). Scanning Electron Microscopy (SEM) was used for morphological observations. Accordingly, the PCL composition in the nanohybrid was determined as 4 %, approximately. Short chained amorphous PCL was synthesized with a number average molecular weight of 4400 g/mol and crystallinity degree of 23 %. In regards to these properties, synthesized PCL/RHA composite can find use biomedical applications.

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Structure and Stability of Olivine Phase FePO4

MRS Proceedings ◽

10.1557/opl.2011.1339 ◽

2011 ◽

Vol 1333 ◽

Cited By ~ 1

Author(s):

Gene M. Nolis ◽

Natalya A. Chernova ◽

Shailesh Upreti ◽

M. Stanley Whittingham

Keyword(s):

Gravimetric Analysis ◽

Li Ion Batteries ◽

X Ray Diffraction ◽

Scanning Calorimetry ◽

Absorption Data ◽

X Ray ◽

Residual Amount ◽

Low Toxicity ◽

Li Ion ◽

Trigonal Phase

ABSTRACTLiFePO4 has shown considerable promise as a cathode material in Li-ion batteries due to its stability, low toxicity and high cyclability. However, the data on thermodynamic stability of olivine phase FePO4 (o-FePO4), the delithiated form of o-LiFePO4, remains scarce and contradictory. In this work, o-FePO4 was synthesized by chemical delithiation of o-LiFePO4 and characterized structurally and thermally. X-ray diffraction and absorption data indicate pure olivine phase, but with residual amount of Fe2+, most likely due to incomplete delithiation. Differential scanning calorimetry and thermal gravimetric analysis reveal that o-LixFePO4 decomposes exothermally above 550 °C with about 9% weight loss, the products being trigonal phase FePO4, Fe7(PO4)6, and LiPO3.

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Synthesis, Characterization andIn VitroAnticancer Evaluation of Itaconic Acid Based Random Copolyester

Journal of Chemistry ◽

10.1155/2014/173814 ◽

2014 ◽

Vol 2014 ◽

pp. 1-7 ◽

Cited By ~ 7

Author(s):

J. Gowsika ◽

R. Nanthini

Keyword(s):

Itaconic Acid ◽

Hydrolytic Degradation ◽

Gel Permeation Chromatography ◽

Xrd Analysis ◽

Titanium Tetraisopropoxide ◽

X Ray Diffraction ◽

Scanning Calorimetry ◽

H Nmr ◽

Melt Polycondensation

The present study deals with the synthesis and characterization of an aliphatic copolyester, poly [butylene fumarate-co-butylene itaconate] (PIFB) copolymer was obtained from itaconic acid, fumaric acid, and 1,4-butanediol using titanium tetraisopropoxide (TTiPO) through a two step process of transesterification and melt polycondensation. The synthesized aliphatic random copolyester was characterized with the help of FT-IR,1H-NMR,13C-NMR, viscosity measurements, Gel Permeation Chromatography (GPC) and X-ray diffraction (XRD) analysis. Thermal properties have been analyzed using thermogravimetric analysis (TGA) and Differential Scanning Calorimetry (DSC). Hydrolytic degradation studies were carried out in acid and alkaline regions of various pH values. The synthesized copolymer was subjected toin vitroanticancer activity studies against human breast cancer (MCF-7) cell line.

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Evidence of Chemical Reaction in Binary Blends of Polycarbonate and a Semi-Flexible Liquid Crystal Polymer

Journal of Research Updates in Polymer Science ◽

10.6000/1929-5995.2021.10.8 ◽

2021 ◽

Vol 10 ◽

pp. 58-68

Author(s):

H. Hakemi ◽

Keyword(s):

Liquid Crystal ◽

Chemical Reaction ◽

Gel Permeation Chromatography ◽

Liquid Crystal Polymer ◽

X Ray Diffraction ◽

Scanning Calorimetry ◽

Binary Blends ◽

Crystal Polymer ◽

Heat Treated ◽

Nmr Techniques

In this study, we provide the experimental results of the binary blends of a semi-flexible nematic liquid crystal polymer (LCP1) and polycarbonate (PC) within their phase diagram. The LCP1/PC blends were investigated by Differential Scanning Calorimetry (DSC), Optical Microscopy (OM), Wide-angle X-Ray Diffraction (WXRD), Fourier Transfer Infrared (FTIR), Gel Permeation Chromatography (GPC), and Nuclear Magnetic Resonance (NMR) techniques and observed the evidence of chemical reaction between LCP1 and PC in their heat-treated blends possibly by transesterification mechanism.

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