scholarly journals New Polymer Syntheses Part 57: Thermally Stable New Ferrocene-Polyazomethines, Synthetic Methodology, and Characterization

2013 ◽  
Vol 2013 ◽  
pp. 1-9 ◽  
Author(s):  
Mona Ahmed Abdel-Rahman ◽  
Mahmoud Ali Hussein ◽  
Kamal Ibrahim Aly ◽  
Abdelwareth Abdel-Haleam Sarhan

A new interesting category of higher thermally stable polyazomethines containing ferrocene in the polymers main chain6a–e  was synthesized by solution-polycondensation reaction of 1-(m-formylphenyl)-1′-(5-formyl-2-methoxyphenyl)-ferrocene monomer4with different aliphatic and aromatic diamines. A model compound5was synthesized from dialdehyde monomer4with aniline and was characterized by elemental and spectral analyses. The desirable resulting polymers were characterized by elemental and spectral analyses, in addition to solubility measurement using different solvents. The thermal properties of these polymers were evaluated by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) measurements. The redox behaviours were studied for the ferrocene polymers in comparison with both the parent ferrocene monomer and the model compound by using cyclic voltammetry (CV).

1996 ◽  
Vol 8 (2) ◽  
pp. 307-314 ◽  
Author(s):  
Kamal I Aly ◽  
Maymona M Kandeel

Bis(2-aminobenzthiazolyl) sulphone (BABS) was used as a new starting material for preparing polyamides. These polyamides were prepared by reacting BABS with adipoyl, sebacoyl, isophthaloyl and terephthaloyl dichlorides, and also with 4,4′-azodibenzoyl chloride or 3,3′-azodibenzoyl chloride, utilizing the solution polycondensation technique at low temperature. In addition, the model compound was synthesized by condensing the BABS with benzoyl chloride. Characterization of the monomer, model compound and the polyamides was accomplished by 1H NMR, IR and elemental analyses. The polyamides had reduced viscosities of 0.25–0.63 dI/g in DMF or DMSO at 25 °C. All the polymers dissolved readily at room temperature in polar aprotic solvents. The thermal stability of the polymers was evaluated by TGA and DSC measurements.


2017 ◽  
Vol 30 (4) ◽  
pp. 437-445 ◽  
Author(s):  
Wadi Elim Sosa-González ◽  
Ramón del Jesús Palí-Casanova ◽  
Yamile Pérez-Padilla ◽  
María Isabel Loría-Bastarrachea ◽  
José Luis Santiago-García ◽  
...  

Several aromatic sulfonated copoly(ether–amide)s, based on the aromatic diamines 4,4′-(hexafluoroisopropylidene)bis(p-phenyleneoxy)-dianiline (HFD) and 2,4-diaminobenzensulfonic acid (DABS) and 4,4′-oxybis(benzoic acid) (OBA), were synthesized through a polycondensation reaction. The sulfonation degree was controlled by introducing different concentrations of 2,4-DABS from 40 mol% up to 80 mol%. Proton nuclear magnetic resonance validated the expected concentrations of sulfonic acid groups in the sulfonated aromatic copoly(ether–amide)s. Thermal decomposition of sulfonic groups was found to initiate at 280°C, while main chain decomposition initiates at 410°C. Proton conductivity between 30°C and 75°C was 19.0 and 45.0 mS/cm, respectively, for the copolymer with the highest concentration of sulfonic groups (–SO3H). Comparison with structurally similar sulfonated copolyamides and copoly(ether–amide)s indicates that these new sulfonated copoly(ether–amide)s based on 4,4′-OBA show improved mechanical properties, but a decrease in ion exchange capacity and proton conductivity.


2006 ◽  
Vol 4 (4) ◽  
pp. 604-619 ◽  
Author(s):  
Ewa Schab-Balcerzak ◽  
Eugenia Grabiec ◽  
Bożena Jarząbek ◽  
Łukasz Grobelny ◽  
Małgorzata Kurcok ◽  
...  

AbstractA series of aromatic poly(amideimide)s containing 9,9-diphenylfluorene moieties and the amide units in the main chain have been synthesized by solution polycondensation reaction of newly prepared diamidedianhydride with several aromatic diamines: 1,3-phenylenediamine, 3,3′-dimethoxy-biphenyl-4,4′-diamine, 4,4′-oxydianiline, 4,4′-(1,3-phenylenedioxy)dianiline, 4,4′-(9-fluorenylidene)dianiline and 1,5-diaminonaphthalene. Molecular structures of the polymers obtained have been characterized using 13C NMR, 1H NMR and FTIR spectroscopies. The polymers prepared are readily soluble in aprotic polar solvents, and form optically transparent films by solution casting. The resultant poly(amideimide)s have been analyzed by differential scanning calorimetry (DSC), thermogravimetry (TG) and wide-angle X-ray diffraction measurements. They exhibited high levels of thermal stability, with decomposition temperatures in the range 452–494 °C, and high glass transition temperatures (181–278 °C). The optical behavior of these polymers has been investigated in NMP solution as well as in the films. The photoluminescence (PL) spectra of the free-standing films prepared from the poly(amideimide)s exhibited maximum emission bands around 506–525 nm in the green region.


Materials ◽  
2021 ◽  
Vol 14 (14) ◽  
pp. 3950
Author(s):  
Abeer Alassod ◽  
Syed Rashedul Islam ◽  
Mina Shahriari Khalaji ◽  
Rogers Tusiime ◽  
Wanzhen Huang ◽  
...  

Compositing is an interesting strategy that has always been employed to introduce or enhance desired functionalities in material systems. In this paper, sponges containing polypropylene, lignin, and octavinyl-polyhedral oligomeric silsesquioxane (OV-POSS) were successfully prepared via an easy and elegant strategy called thermally induced phase separation (TIPS). To fully explore the behaviour of different components of prepared sponges, properties were characterized by a thermogravimetric analyser (TGA), differential scanning calorimetry (DSC), Fourier transform infrared measurement (FTIR), and scanning electron microscopy (SEM). Furthermore, wettability properties toward an organic liquid and oil were investigated. The FTIR analysis confirmed the chemical modification of the components. TGA and DSC measurements revealed thermal stability was much better with an increase in OV-POSS content. OV-POSS modified sponges exhibited ultra-hydrophobicity and high oleophilicity with water contact angles of more than 125°. The SEM revealed that POSS molecules acted as a support for reduced surface roughness. Moreover, OV-POSS-based blend sponges showed higher sorption capacities compared with other blend sponges without OV-POSS. The new blend sponges demonstrated a potential for use as sorbent engineering materials in water remediation.


1997 ◽  
Vol 37 (8) ◽  
pp. 1381-1386 ◽  
Author(s):  
M. Ya. Goykhman ◽  
V. M. Svetlichnyi ◽  
V. V. Kudriavtsev ◽  
N. G. Antonov ◽  
Yu. N. Panov ◽  
...  

2011 ◽  
Vol 76 (5) ◽  
pp. 553-566
Author(s):  
Christian Näther ◽  
Inke Jeß

Clobetasone butyrate was investigated for polymorphism and pseudopolymorphism. Solvent mediated conversion experiments reveal that the commercially available form I represent the thermodynamically most stable form at room temperature and DSC measurements shows that it should also be the most stable form until melting. Form I crystallizes in space groupP212121with three crystallographically independent molecules of similar conformation. From methanol an additional pseudo polymorphic form was discovered. In the crystal structure (space groupP212121) the solvent molecules are connected to the clobetasone butyrate molecules by O–H···O hydrogen bonding. Investigations of the solvate using thermogravimetry, differential thermoanalysis as well as differential scanning calorimetry proves, that on solvent removal an amorphous form is obtained that crystallizes into form I on further heating.


2021 ◽  
Vol 882 ◽  
pp. 21-27
Author(s):  
Seyed Veghar Seyedmohammadi ◽  
Amin Radi ◽  
Guney Guven Yapici

In the present work, the effects of artificial aging treatment on the transformation temperatures and hardness of Cu-Al-Mn shape memory alloy have been investigated. The aging processes have been performed on the one-time re-melted and 90% rolled samples. Differential scanning calorimetry reveals that reverse transformation is present for the re-melted sample which is aged at 400°C. However, in 90% rolled condition, this transformation takes place at 200°C and 300°C. Hardness examination shows that the aged specimens possess higher values in hardness in comparison to un-aged samples at all studied temperatures. Although, the peak-aged condition was demonstrated at 300°C for the re-melted sample, the rolled sample displayed increased hardness levels up to 500°C. Based on the DSC measurements and microstructural observations, it can be asserted that the thermo-mechanical processing including rolling plus aging at 300°C provides favorable transformation characteristics for shape memory behavior.


Materials ◽  
2020 ◽  
Vol 13 (13) ◽  
pp. 3035
Author(s):  
Dovydas Karoblis ◽  
Diana Griesiute ◽  
Kestutis Mazeika ◽  
Dalis Baltrunas ◽  
Dmitry V. Karpinsky ◽  
...  

In this study, a highly crystalline bismuth ferrite (BFO) powder was synthesized using a novel, very simple, and cost-effective synthetic approach. It was demonstrated that the optimal annealing temperature for the preparation of highly-pure BFO is 650 °C. At lower or higher temperatures, the formation of neighboring crystal phases was observed. The thermal behavior of BFO precursor gel was investigated by thermogravimetric and differential scanning calorimetry (TG-DSC) measurements. X-ray diffraction (XRD) analysis and Mössbauer spectroscopy were employed for the investigation of structural properties. Scanning electron microscopy (SEM) was used to evaluate morphological features of the synthesized materials. The obtained powders were also characterized by magnetization measurements, which showed antiferromagnetic behavior of BFO powders.


2012 ◽  
Vol 31 (1) ◽  
pp. 79
Author(s):  
Khalil Faghihi ◽  
Masoumeh Soleimani ◽  
Shabnam Nezami ◽  
Meisam Shabanian

Two new samples of poly(amide-imide)-montmorillonite reinforced nanocomposites containing N-trimellitylimido-L-valine moiety in the main chain were synthesized by a convenient solution intercalation technique. Poly(amide-imide) (PAI) 5 as a source of polymer matrix was synthesized by the direct polycondensation reaction of N-trimellitylimido-L-valine (3) with 4,4′-diaminodiphenyl ether 4 in the presence of triphenyl phosphite (TPP), CaCl2, pyridine and N-methyl-2-pyrrolidone (NMP). Morphology and structure of the resulting PA-nanocomposite films (5a) and (5b) with 10 and 20 % silicate particles were characterized by FTIR spectroscopy, X-ray diffraction (XRD) and scanning electron microscopy (SEM). The effect of clay dispersion and the interaction between clay and polymeric chains on the properties of nanocomposite films were investigated by using Uv-vis spectroscopy,  thermogravimetric analysis (TGA) and water uptake measurements.


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