Synthesis and Characterization of Porous Crosslinked Copolymers for Oil Spill Sorption

e-Polymers ◽  
2007 ◽  
Vol 7 (1) ◽  
Author(s):  
Abdel-Azim A. Abdel-Azim ◽  
A. Mahmoud Abdul-Raheim ◽  
Ayman Mohamady Atta ◽  
Witold Brostow ◽  
A. Fawzy El-Kafrawy

AbstractCinnamoyloxy ethyl methacrylate (CEMA) was copolymerized with different monomer feed ratios of octadecyl acrylate (ODA) and crosslinked using azobisisobutyronitrile (AIBN) as the initiator and N,N’,N”-trisacryloyl melanine (AM) or N,N’,N”,-trismethacryloylmelanine (MM) crosslinkers. The networks are characterized by scanning electron microscopy (SEM), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and dynamic mechanical analysis (DMA). For crosslinked CEMA/ODA copolymer sol fraction values are lower when MM is used rather than AM. The thermal stability of crosslinked network increases with increasing ODA concentration and also in the presence of MM crosslinker, a consequence of higher crosslinking density. SEM results show a porous structure; micropores are formed when ODA contents increases. According to DMA results, the flexibility of the network is enhanced by incorporation of MM rather than AM. Since our crosslinked networks are both flexible and porous, they are applicable as oil sorber networks to alleviate pollution from oil spills.

2011 ◽  
Vol 327 ◽  
pp. 115-119 ◽  
Author(s):  
Duo Wang ◽  
Jie Gao ◽  
Wei Fang Xu ◽  
Feng Bao ◽  
Rui Ma ◽  
...  

Graphene oxide (GO) was made by a modified Hummers method. Graphene oxide modified phenolic resin nanocomposites (GO/PF) were prepared by Steglich esterification, catalyzed by dicyclohexyl carbodiimide and 4-dimethylaminopyridine. The composites were characterized by Fourier transform infrared spectrometry, differential scanning calorimetry, X-ray powder diffraction, and scanning electron microscopy. The result revealed that the graphene oxide was absolutely exfoliated and covalent linked GO/PF composite was obtained. The thermal stability of PF is remarkably improved by modification with GO.


2012 ◽  
Vol 488-489 ◽  
pp. 506-510 ◽  
Author(s):  
Sikander Rafiq ◽  
Zakaria Man ◽  
Abdulhalim Maulud ◽  
Nawshad Muhammad ◽  
Saikat Maitra

Composite membranes were prepared by incorporating inorganic silica nanoparticles into blends of polysulfone/polyimide (PSF/PI) membranes via sol-gel route. Morphological structures of the developed membranes were carried out by scanning electron microscopy (SEM). Spectroscopic analysis of the hybrid membranes were done by fourier transform infrared spectroscopy (FTIR) analysis. Differential scanning calorimetry (DSC) analysis shows that the glass transition temperature (Tg) increased from 209oC to 238oC in the hybrid membranes followed by thermogravimetric analysis (TGA) that showed significant improvement in thermal stability of the developed membranes.


2011 ◽  
Vol 675-677 ◽  
pp. 295-298
Author(s):  
Liang Shao ◽  
Jian Hui Qiu ◽  
Ming Zhu Liu ◽  
Hui Xia Feng ◽  
Guo Hong Zhang ◽  
...  

New types of conducting composites using andalusite as an inorganic substrate and polyaniline as the conducting phase were prepared. The composites exhibited conductivities in the 0.14-2.08 S/cm range, depending on the amount of polyaniline. The thermal stability of andalusite/polyaniline composites were studied by thermogravimetric analysis. The resulting composites were also characterized by using FTIR spectroscopy and scanning electron microscopy.


2016 ◽  
Vol 71 (12) ◽  
pp. 1199-1209
Author(s):  
Vera A. Hartdegen ◽  
Maximilian S. Hofmayer ◽  
Konstantin Karaghiosoff ◽  
Thomas M. Klapötke

AbstractOn the basis of 1,2-bis(5-tetrazolo)ethane (BTE) the corresponding twofold vinyl and allyl N-substituted derivatives were synthesized using 1,2-dibromoethane and allyl bromide, respectively. The compounds were obtained as two different constitutional isomers. Both species were analyzed using NMR and IR spectroscopy, elemental analysis, as well as mass spectrometry. In the case of the diallyl bistetrazoles, the two isomers were characterized using 2D NMR spectroscopy. The synthesis of the divinyl compounds gave crystals of the 2,2′-N-substituted isomer, which were analyzed by single-crystal X-ray diffraction. The thermal stability of the compounds was determined using differential scanning calorimetry (DSC) and gave decomposition temperatures around 190°C and 230°C. For the investigation of the inherent energetic potential, sensitivities toward physical stimuli and detonation parameters were determined. The compounds turned out to be insensitive toward friction and impact and possess moderate energetic properties.


2020 ◽  
Vol 9 (11) ◽  
pp. e45791110207
Author(s):  
Yuri Johann Vilar de Brito ◽  
Crislene Rodrigues da Silva Morais ◽  
Yohanna Jamilla Vilar de Brito ◽  
Daniella Cibele Bezerra

In this work the complexes Ln(β-dik)3L (where Ln= Nd+3 e Er+3, β-dik= 4,4,4-trifluoro-1-phenyl-1,3-butanedione (Btfa) and L= 1,10-Phenanthroline (Phen) or 2,2’-Bipyridyl (Bipy)), were synthesized from the direct reaction of LnCl3 with β-diketone and the ligands. The purpose was to create new lanthanide complexes with perspectives of use in markers. After the syntheses, the complexes were characterized by Solubility Test, Scanning Electron Microscopy (SEM) and the thermal properties of compounds were studied using Thermogravimetry Analisys (TGA), Differential Scanning Calorimetry (DSC) and Determination of Melting/Decomposition Intervals. Based on the verified properties, the solubility test found that the complexes are not soluble in chloroform and water. The microscope images showed an excellent crystallization of the complexes. The complexes are stable up to 120°C, after this temperature they show a peak in the DSC referring to the fusion and the beginning of decomposition. The values of activation energy suggests the following decreasing order of stability: Er(Btfa)3Phen>Nd(Btfa)3Phen>Er(Btfa)3Bipy>Nd(Btfa)3Bipy.


Author(s):  
R.A. Shulen ◽  
◽  
D.S. Kazybayeva ◽  

The work is devoted to the synthesis and characterization of gels based on the monomers pentaerythritol triaacrylate (PETriA) and 2,2 '-(ethylenedioxy)diethanethiol (EDODET) by thiol-ene "click" polymerization. The properties of the obtained gels were investigated by IR, Raman spectroscopy, mechanical analysis. Sol-gel analysis of obtained networks was carried out and the degradability was investigated. The results of IR spectroscopy confirmed the presence of -C = O and -C-O-C- groups in the composition of the obtained gels. The presence of unreacted C = C bonds conjugated with C = O, as well as thiol groups, varies depending on the composition of the initial monomer mixture (IMM). Raman spectroscopy results correlate well with IR data. Raman spectra also show C-S, S-S and SH characteristic bands that are difficult to identify by IR spectroscopy. It was found that the composition of MM affects the physicochemical properties of the synthesized gels. The highest yield of the gel fraction of obtained polymers was found in samples with an equimolar composition of IMM. The analysis of mechanical properties showed that gels with an excess of PETriA exhibit more elastic properties, and an excess of EDODET leads to the formation of networks with a higher crosslinking density. The study of the ability of obtained PETria-EDODET gels to degrade in a 3% solution of hydrogen peroxide showed that the polymer network degrades by 12% within 60 days. This property of the obtained gels can find application in the creation of targeted drug delivery systems with their prolonged release.


2009 ◽  
Vol 1243 ◽  
Author(s):  
M.C. Chavarría-Gaytán ◽  
I. Olivas-Armendáriz ◽  
P.E. García-Casillas ◽  
A. Martínez-Villafañe ◽  
C. A. Martínez-Pérez

ABSTRACTPolyurethanes are interesting materials that can be used in biomedical applications for regeneration of bone tissue. In this work the synthesis and characterization of porous polyurethanes to act as scaffold is performed by a thermally induced phase separation technique. The appropriate parameters are determined in order to obtain a porous well interconnected material. Characterization by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) is made in order to determine the thermal stability of the material. Chemical characterization is made by Fourier transformed infrared spectroscopy with attenuated total reflectance (FTIR-ATR). The morphology of the material is observed by a field emission scanning electron microscope (FESEM) and the mechanical properties are measured by dynamic mechanical analysis (DMA).


Author(s):  
Danny Illera Perozo ◽  
Humberto Gómez Vega ◽  
Julian Yepes Martínez

The synthesis and characterization of Polyaniline/Graphene/ Nanodiamond Nanocomposite is reported. The resulting materials were synthetized following a polymerization in situ scheme and characterized by Fourier Transform Infrared Spectroscopy (FTIR), Thermogravimetry (TGA), Differential Scanning Calorimetry (DSC), Scanning Electron Microscopy (SEM) and Cyclic Voltammetry (CV). The effect of different loads of graphene and nanodiamond on the resulting nanocomposite was studied. Despite the presence of the host materials, the formation of Polyaniline polymer is successfully accomplished for all samples. The microstructure of the resulting materials is core-shell type with the additives being covered (core) by layers of the conjugated polymer (shell). The thermal stability of the nanocomposites is improved as confirmed by measuring an increase on the Temperature of Decomposition and the Cross-Linking Temperature compared to bare polymer. Electrochemical characterization reveals that the presence of the additives does not affect the electroactive behaviour of the matrix polymer allowing it to reversely shift from different oxidation stages. The effect of additive content on the charge transfer kinetics is discussed.


1999 ◽  
Vol 14 (5) ◽  
pp. 1805-1813 ◽  
Author(s):  
Florence Fusalba ◽  
Daniel Bélanger

A novel polyaniline-molybdenum trisulfide composite has been prepared by chemical polymerization from an acidic (1 M HCl) aqueous solution containing aniline and ammonium tetrathiomolybdate. The presence of molybdenum trisulfide in the polyaniline matrix induces morphological change to the polymer as evidenced by scanning electron micrographs. X-ray diffraction and differential scanning calorimetry indicate that polyaniline-molybdenum trisulfide is slightly less crystalline than polyaniline-HCl. X-ray photoelectron spectroscopy (XPS) and elemental analysis have been used to confirm the presence of molybdenum trisulfide in the polymer matrix. The XPS data also confirm that molybdenum trisulfide and tetrathiomolybdate anions are present with polyaniline to form a new inorganic-organic composite.


2014 ◽  
Vol 69 (1) ◽  
pp. 77-82 ◽  
Author(s):  
Xu Zhibin ◽  
Cui Kejian ◽  
Wang Peng ◽  
Lin Zhihui ◽  
Meng Zihui ◽  
...  

A new approach is described to synthesize 2-(dinitromethylene)-l-nitro-1,3-diazacyclopentane (4). 2-(Dinitromethylene)-1,3-diazacyclopentane (1) was synthesized first by the nucleophilic substitution of ethylenediamine and 1,1-diamino-2,2-dinitroethylene (FOX-7) catalyzed by Mg(OAc)2, then 1 was transformed to 4 through nitration, reduction and hydrolysis. The crystal morphology of 4 was investigated by scanning electron microscopy (SEM). Compound 4 was also characterized by IR, NMR, MS and elemental analysis, and by thermogravimetry (TG) and differential scanning calorimetry (DSC), which revealed that 4 decomposes at 126 °C. The explosive performance of 4 was calculated using the VLW equation. The crystal density of 4 was determined as 1.79 g ·cm-3. The experimental results indicate that 4 is sensitive towards impact and spark stimuli, but insensitive to friction.


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