scholarly journals Pentaborate(1-) Salts and a Tetraborate(2-) Salt Derived from C2- or C3-Linked Bis(alkylammonium) Dications: Synthesis, Characterization, and Structural (XRD) Studies

Molecules ◽  
2019 ◽  
Vol 25 (1) ◽  
pp. 53 ◽  
Author(s):  
Michael A. Beckett ◽  
Bashdar I. Meena ◽  
Thomas A. Rixon ◽  
Simon J. Coles ◽  
Peter N. Horton
Keyword(s):  
Aqueous Solution ◽  
13C Nmr ◽  
Thermal Gravimetric Analysis ◽  
Gravimetric Analysis ◽  
Single Crystal Xrd ◽  
Thermal Gravimetric ◽  
Bet Analysis ◽  
Xrd Studies ◽  
Work Up ◽  
Moderate Yield

The synthesis of a number of pentaborate(1-) salts from cations arising from N-substituted α,α-, α,β-, and α,γ-diaminoalkanes has been attempted in aqueous solution from B(OH)3 and the appropriate diammine in a 10:1 ratio. Despite relatively mild work-up conditions the pentaborate(1-) salts prepared were not always as anticipated and the following compounds were isolated in good yield: [Me2NH(CH2)2NHMe2][B5O6(OH)4]2 (1), [Et2NH(CH2)2NHEt2][B5O6(OH)4]2 (2), [Et2NH2][B5O6(OH)4] (3), [Me2NH2][B5O6(OH)4] (4), [Me2NH(CH2)3NHMe2][B5O6(OH)4]2 (5), [Et2NH(CH2)3NHEt2][B5O6(OH)4]2 (6), [Me3NCH2CH=CH2][B5O6(OH)4] (7), and [Me3N(CH2)3NMe3] [B5O6(OH)4]2.0.5H2O (8). The tetraborate(2-) salt, [Me3N(CH2)2NMe3][B4O5(OH)4].2B(OH)3.2H2O (9) was obtained in moderate yield (41%) from a 3:1 reaction of B(OH)3 with [Me3N(CH2)2NMe3](OH)2. All compounds were characterized by spectroscopy (1H, 11B, 13C NMR and IR) and thermal gravimetric analysis (TGA). BET analysis on materials derived thermally from selected samples (1, 2, 6, 7) all had porosities of < 1 m2/g, demonstrating that they were non-porous. Single-crystal XRD structures were obtained for 2, 3, 7, 8 and 9 and all contain extensive H-bonded polyborate lattices.

scholarly journals Superparamagnetic Behaviour and Surface Analysis of Fe3O4/PPY/CNT Nanocomposites

2020 ◽  
Vol 2020 ◽  
pp. 1-6
Author(s):  
Juniastel Rajagukguk ◽  
Pintor Simamora ◽  
C. S. Saragih ◽  
Hairus Abdullah ◽  
Noto Susanto Gultom ◽  
...  
Keyword(s):  
Carbon Nanotubes ◽  
Thermal Properties ◽  
Surface Analysis ◽  
Thermal Gravimetric Analysis ◽  
Potential Application ◽  
Gravimetric Analysis ◽  
Thermal Gravimetric ◽  
Superparamagnetic Behaviour ◽  
Bet Analysis ◽  
Natural Iron

The superparamagnetic property of nanomaterials such as Fe3O4 has been considered to be promising for various applications. In this paper, Fe3O4/PPY/CNT nanocomposites were synthesized with utilizing natural iron sand by a coprecipitation method. The as-precipitated Fe3O4 NPs were combined with carbon nanotubes (CNTs) using conductive polypyrrole (PPY) as linking agents. The Fe3O4/PPY/CNT nanocomposites were systematically characterized by FE-SEM, EDS, XRD, BET, and FTIR. Furthermore, the effects of CNTs on magnetic and thermal properties of nanocomposites were investigated by VSM and thermal gravimetric analysis (TGA), respectively. The composites exhibited significant decrease of coercivity value with the content of CNTs increasing. The VSM result confirmed that Fe3O4/PPY/CNT nanocomposites were superparamagnetic. It was found that by increasing the amounts of CNTs, the magnetization of Fe3O4/PPY/CNT nanocomposites gradually decreased. The addition of CNTs is intended to improve the mesoporous property as proved by BET analysis which has the potential application as a nanocatalyst.

Thermal gravimetric analysis of in-situ crosslinked nanocellulose whiskers • poly(methyl vinyl ether-co-maleic acid) • polyethylene glycol

TAPPI Journal ◽  
2011 ◽  
Vol 10 (4) ◽  
pp. 29-33
Author(s):  
LEE A. GOETZ ◽  
AJI P. MATHEW ◽  
KRISTIINA OKSMAN ◽  
ARTHUR J. RAGAUSKAS
Keyword(s):  
Thermal Stability ◽  
Polyethylene Glycol ◽  
Vinyl Ether ◽  
Thermal Gravimetric Analysis ◽  
Maleic Acid ◽  
Gravimetric Analysis ◽  
Thermal Gravimetric ◽  
Methyl Vinyl ◽  
Methyl Vinyl Ether

The thermal stability and decomposition of in-situ crosslinked nanocellulose whiskers – poly(methyl vinyl ether-co-maleic acid) – polyethylene glycol formulations (PMVEMA-PEG), (25%, 50%, and 75% whiskers) – were investigated using thermal gravimetric analysis (TGA) methods. The thermal degradation behavior of the films varied according to the percent cellulose whiskers in each formulation. The presence of cellulose whiskers increased the thermal stability of the PMVEMA-PEG matrix.

Characterization of the electrocatalytic activity of carbon-supported platinum-based catalysts by thermal gravimetric analysis

2015 ◽  
Vol 25 (6) ◽  
pp. 468-469 ◽  
Author(s):  
Igor N. Leontyev ◽  
Daria V. Leontyeva ◽  
Alexandra B. Kuriganova ◽  
Yurii V. Popov ◽  
Olga A. Maslova ◽  
...  
Keyword(s):  
Thermal Gravimetric Analysis ◽  
Electrocatalytic Activity ◽  
Gravimetric Analysis ◽  
Thermal Gravimetric ◽  
Supported Platinum

scholarly journals Synthesis, characterization and photoinduced curing of polysulfones with (meth)acrylate functionalities

2010 ◽  
Vol 6 ◽  
Author(s):  
Cemil Dizman ◽  
Sahin Ates ◽  
Lokman Torun ◽  
Yusuf Yagci
Keyword(s):  
Molecular Weight ◽  
Thermal Properties ◽  
Thermal Gravimetric Analysis ◽  
Gravimetric Analysis ◽  
Condensation Polymerization ◽  
Thermal Gravimetric ◽  
Uv Curable ◽  
H Nmr ◽  
Rate Of Polymerization ◽  
Photo Curing

The UV-curable telechelic polysulfones with (meth)acrylate functionalities were synthesized by condensation polymerization and subsequent esterification. The final polymers and intermediates at various stages were characterized by 1H NMR, FT-ATR, and GPC. The oligomeric films prepared from the appropriate solutions containing these telechelics and 2,2-dimethoxy-2-phenylacetophenone (DMPA) as the photoinitiator undergo rapid polymerization upon irradiation forming insoluble networks. The photo-curing behavior was investigated by photo-DSC and the effects of the molecular weight of the polysulfone precursor and type of functionality on the rate of polymerization and conversion were evaluated. Thermal properties of the photochemically cured films were studied by differential scanning calorimeter (DSC) and thermal gravimetric analysis (TGA).

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