Poly(imide-amide)s and poly(imide-ester)s obtained fromN,N′-(4,4′-Me,R-diphthaloyl)-bis-glycine acid dichloride (R=Me, Et): Synthesis, characterization, and thermal studies

2010 ◽  
pp. NA-NA ◽  
Author(s):  
L. H. Tagle ◽  
C. A. Terraza ◽  
A. Leiva ◽  
N. Yazigi ◽  
L. Lopez
Keyword(s):  
Thermal Studies ◽  
Acid Dichloride ◽  
Poly Imide

Poly(amide) oligomers with silarylene and/or germarylene units – synthesis, characterization and thermal studies

e-Polymers ◽  
2009 ◽  
Vol 9 (1) ◽  
Author(s):  
Luis H. Tagle ◽  
Claudio A. Terraza ◽  
Angel Leiva ◽  
Patricia Alvarez
Keyword(s):  
Main Chain ◽  
Effective Interaction ◽  
Thermal Studies ◽  
The Other ◽  
Spectroscopic Techniques ◽  
Aromatic Diamines ◽  
Packing Factor ◽  
Degradation Temperature ◽  
General Terms ◽  
Acid Dichloride

AbstractTen poly(amide) oligomers were prepared from four acid dichlorides and two full-aromatic diamines, the latter containing silicon or germanium in their structure. The polymers, which contain Et/Me, Et/Et and nBu/nBu combinations on heteroatom of the acid dichloride moiety, were characterized by spectroscopic techniques, including 29Si NMR. The yields obtained and the ηιnh values established were low, indicating the low molecular weight nature of the polymers. Thermal stability was also evaluated by TG and DSC techniques. When a methyl group was replaced by a Et, the Tg of the poly(amides) (PAs) was increased in accordance with the gain in the flexibility of the chain. However and in general terms, the PAs with nBu groups show the inverse effect. Probably, the possibility of an effective interaction between these side chains affects negatively the flexibility of the main chain. On the other hand, PAs that contain single silicon in their structure show lower Tg values than the Ge-containing PAs. For the other heteroatom combinations, similar results were obtained. This fact does not agree with the lower size of silicon atom which should increase the molecular rigidity and therefore their Tg values. Probably, the influence of the side groups is decisive in hindering the chain rotation. The thermal degradation temperature (TDT) changed in agreement with the packing factor of the chains which was depending on the size of substitute groups. So, when Et group was replaced by nBu as lateral group, lower TDT were recovered. With respect to the heteroatoms used in the main chain, the TDT values do not show a clear tendency.

scholarly journals SYNTHESIS, CHARACTERIZATION AND THERMAL STUDIES OF WHOLLY AROMATIC POLY(IMIDE-AMIDES) CONTAINING SI AND/OR GE IN THE MAIN CHAIN

2011 ◽  
Vol 56 (4) ◽  
pp. 945-947 ◽  
Author(s):  
L.H TAGLE ◽  
C.A TERRAZA ◽  
P.A ORTIZ ◽  
A TUNDIDOR-CAMBA
Keyword(s):  
Main Chain ◽  
Thermal Studies ◽  
Poly Imide

scholarly journals SILICON-CONTAINING POLY(IMIDE-AMIDES) DERIVED FROM ALIPHATIC DIACIDS WITH NAPHATHALIMIDYL SIDE GROUPS: SYNTHESIS AND THERMAL STUDIES

2013 ◽  
Vol 58 (4) ◽  
pp. 2114-2116 ◽  
Author(s):  
L.H. TAGLE ◽  
C.A. TERRAZA ◽  
A TUNDIDOR-CAMBA ◽  
F.A. LARA
Keyword(s):  
Thermal Studies ◽  
Poly Imide

Structure of junction zones in poly (vinyl alcohol) gels by rheological and thermal studies

1996 ◽  
Vol 93 ◽  
pp. 880-886 ◽  
Author(s):  
K Nishinari ◽  
M Watase ◽  
F Tanaka
Keyword(s):  
Vinyl Alcohol ◽  
Thermal Studies ◽  
Poly Vinyl Alcohol

Synthesis, Characterization and Thermal studies of Novel Organomercury Driven from Sulfa Drugs Part 1

2011 ◽  
Vol 7 (2) ◽  
pp. 1338-1347
Author(s):  
Tarek Ali Fahad ◽  
Shaker.A.N. AL-Jadaan
Keyword(s):  
Thermal Decomposition ◽  
Thermal Behavior ◽  
1H Nmr ◽  
Elemental Analysis ◽  
Thermal Studies ◽  
Spectroscopic Techniques ◽  
Sulfa Drugs ◽  
Acid Base ◽  
Ph Values ◽  
Multi Stage

Two new heterocyclic Organmercury compounds   were prepared from the reaction of Sulfamethaxazole and Sulfadiazine with 4-acetaminophenol as a coupler and separated as solids with characteristic colors. these compounds were characterized by F.T.IR-spectroscopy 1H-NMR , Micro-elemental Analysis and UV-Vis spectroscopic techniques . The work involves a study of acid – base properties compounds at different pH values, the ionization and protonation constants were calculated. The thermal behavior of these two compounds   were investigated on the basis of thermogravimetric (TGA) and differential thermogravimetric (DTG) analyses, Thermal decomposition of these compounds is multi-stage processes.

THERMAL STUDIES ABOUT THE HIGH TEMPERATURE ENGINEERING TEST REACTOR

2016 ◽  
Author(s):  
Maria Elizabeth Scari ◽  
Antonella Lombardi Costa
Keyword(s):  
High Temperature ◽  
Thermal Studies ◽  
Test Reactor

Spectral and Thermal Studies of Mo and Mn d-glucose Complexes.

2014 ◽  
Vol 7 (7) ◽  
pp. 1-21
Author(s):  
M. Massoud ◽  
A. Elkholany ◽  
M. El- Shahat
Keyword(s):  
Thermal Studies

scholarly journals First thermal studies on visible-light-switchable negative T-type photochromes of a nitrile-rich series

RSC Advances ◽  
2021 ◽  
Vol 11 (34) ◽  
pp. 21097-21103
Author(s):  
Mikhail Yu. Belikov ◽  
Mikhail Yu. Ievlev
Keyword(s):  
Thermal Stability ◽  
Visible Light ◽  
Temperature Effect ◽  
Thermal Studies ◽  
First Time ◽  
Thermal Stability Of

The temperature effect on the thermal stability of both the initial and photoinduced forms of nitrile-rich T-type photochromes was studied for the first time.

scholarly journals Crystallization Behavior and Mechanical Properties of Poly(ε-caprolactone) Reinforced with Barium Sulfate Submicron Particles

Materials ◽  
2021 ◽  
Vol 14 (9) ◽  
pp. 2368
Author(s):  
Hegoi Amestoy ◽  
Paul Diego ◽  
Emilio Meaurio ◽  
Jone Muñoz ◽  
Jose-Ramon Sarasua
Keyword(s):  
Barium Sulfate ◽  
Thermal Studies ◽  
Polarized Light ◽  
Optical Microscope ◽  
Submicron Particles ◽  
Degree Of Crystallinity ◽  
Scanning Calorimetry ◽  
Nucleation Effect ◽  
Crystal Fraction ◽  
Light Optical Microscope

Poly(ε-caprolactone) (PCL) was mixed with submicron particles of barium sulfate to obtain biodegradable radiopaque composites. X-ray images comparing with aluminum samples show that 15 wt.% barium sulfate (BaSO4) is sufficient to present radiopacity. Thermal studies by differential scanning calorimetry (DSC) show a statistically significant increase in PCL degree of crystallinity from 46% to 52% for 25 wt.% BaSO4. Non-isothermal crystallization tests were performed at different cooling rates to evaluate crystallization kinetics. The nucleation effect of BaSO4 was found to change the morphology and quantity of the primary crystals of PCL, which was also corroborated by the use of a polarized light optical microscope (PLOM). These results fit well with Avrami–Ozawa–Jeziorny model and show a secondary crystallization that contributes to an increase in crystal fraction with internal structure reorganization. The addition of barium sulfate particles in composite formulations with PCL improves stiffness but not strength for all compositions due to possible cavitation effects induced by debonding of reinforcement interphase.

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