scholarly journals STUDY OF THERMAL CHARACTERISTICS OF THE EUROPIUM (III) COMPLEX WITH HIGH-MOLECULAR HEPARIN

2020 ◽  
pp. 32-40
Author(s):  
Михаил Игоревич Скобин ◽  
Тимофей Владимирович Крюков ◽  
Мариана Александровна Феофанова ◽  
Надежда Владимировна Баранова
Keyword(s):  
Thermal Stability ◽  
Thermal Analysis ◽  
Molecular Weight ◽  
Ir Spectroscopy ◽  
Thermal Degradation ◽  
High Molecular Weight ◽  
Complex Compound ◽  
Thermal Characteristics ◽  
Solid Complex ◽  
Crystallization Water

Синтезировано твердое комплексное соединение высокомолекулярного гепарина с европием (III) ([EuHep]•3HO). Проведен синхронный термический анализ [EuHep]•3HO. Определены термическая устойчивость, температура дегидратации и количество кристаллизационной воды, количество металла в комплексе. Описаны наиболее значимые стадии термодеструкции и на основе данных ИК-спектроскопии предположены образующиеся продукты. A solid complex compound of high molecular weight heparin with europium (III) was synthesized. A synchronous thermal analysis of [EuHep]•3HO was performed. Thermal stability, dehydration temperature and the amount of crystallization water, the amount of metal in the complex are determined. The most significant stages of thermal degradation are described and, based on the data of IR spectroscopy, the products formed are assumed.

scholarly journals Thermal Degradation Kinetics and Modeling Study of Ultra High Molecular Weight Polyethylene (UHMWP)/Graphene Nanocomposite

Molecules ◽  
2021 ◽  
Vol 26 (6) ◽  
pp. 1597
Author(s):  
Iman Jafari ◽  
Mohamadreza Shakiba ◽  
Fatemeh Khosravi ◽  
Seeram Ramakrishna ◽  
Ehsan Abasi ◽  
...  
Keyword(s):  
Thermal Stability ◽  
Molecular Weight ◽  
Thermal Degradation ◽  
High Molecular Weight ◽  
Degradation Kinetics ◽  
Graphene Nanosheets ◽  
Thermal Degradation Kinetics ◽  
Graphene Nanocomposites ◽  
Kinetics Of ◽  
Ultra High Molecular Weight

The incorporation of nanofillers such as graphene into polymers has shown significant improvements in mechanical characteristics, thermal stability, and conductivity of resulting polymeric nanocomposites. To this aim, the influence of incorporation of graphene nanosheets into ultra-high molecular weight polyethylene (UHMWPE) on the thermal behavior and degradation kinetics of UHMWPE/graphene nanocomposites was investigated. Scanning electron microscopy (SEM) analysis revealed that graphene nanosheets were uniformly spread throughout the UHMWPE’s molecular chains. X-Ray Diffraction (XRD) data posited that the morphology of dispersed graphene sheets in UHMWPE was exfoliated. Non-isothermal differential scanning calorimetry (DSC) studies identified a more pronounced increase in melting temperatures and latent heat of fusions in nanocomposites compared to UHMWPE at lower concentrations of graphene. Thermogravimetric analysis (TGA) and derivative thermogravimetric (DTG) revealed that UHMWPE’s thermal stability has been improved via incorporating graphene nanosheets. Further, degradation kinetics of neat polymer and nanocomposites have been modeled using equations such as Friedman, Ozawa–Flynn–Wall (OFW), Kissinger, and Augis and Bennett’s. The "Model-Fitting Method” showed that the auto-catalytic nth-order mechanism provided a highly consistent and appropriate fit to describe the degradation mechanism of UHMWPE and its graphene nanocomposites. In addition, the calculated activation energy (Ea) of thermal degradation was enhanced by an increase in graphene concentration up to 2.1 wt.%, followed by a decrease in higher graphene content.

Semi-bio-based aromatic polyamides from 2,5-furandicarboxylic acid: toward high-performance polymers from renewable resources

RSC Advances ◽  
2016 ◽  
Vol 6 (90) ◽  
pp. 87013-87020 ◽  
Author(s):  
Kaiju Luo ◽  
Yan Wang ◽  
Junrong Yu ◽  
Jing Zhu ◽  
Zuming Hu
Keyword(s):  
Mechanical Properties ◽  
Thermal Stability ◽  
Molecular Weight ◽  
High Molecular Weight ◽  
Renewable Resources ◽  
High Performance ◽  
Good Thermal Stability ◽  
Aromatic Polyamides ◽  
High Performance Polymers ◽  
Furandicarboxylic Acid

Aromatic furanic polyamides with relatively high molecular weight were synthesized, and good thermal stability and mechanical properties were demonstrated.

scholarly journals Synthesis, Characterization and Thermal Analysis of New Cu(II) Complexes with Hydrazide Ligands

2010 ◽  
Vol 7 (s1) ◽  
pp. S278-S282 ◽  
Author(s):  
Saber Rajaei ◽  
Shahriare Ghammamy ◽  
Kheyrollah Mehrani ◽  
Hajar Sahebalzamani
Keyword(s):  
Thermal Stability ◽  
Thermal Analysis ◽  
Acetic Acid ◽  
Ir Spectroscopy ◽  
Coordination Mode ◽  
Azomethine Nitrogen ◽  
Excellent Thermal Stability ◽  
Spectral Techniques ◽  
Ft Ir ◽  
New Compounds

A number of new complexes have been synthesized by reaction of novel ligands acetic acid(4-methyl-benzylidene)hydrazide (L1) and acetic acid(naphthalen-1-ylmethylene)hydrazide (L2) with copper(II) nitrate. These new compounds were characterized by elemental analysis, TG, DTA, IR spectroscopy, UV spectral techniques. The changes observed between the FT-IR and UV-Vis spectra of the ligands and of the complexes allowed us to establish the coordination mode of the metal in complexes. The results suggest that the Schiff bases L1and L2coordinate as univalent anions with their bidentate N,O donors derived from the carbonyl and azomethine nitrogen. Also the probing of thermal analysis complexes can detect which complex has excellent thermal stability.

Mechanical and Thermal Properties of PLA Melt Blended with High Molecular Weight PEG Modified with Peroxide and Organo-Clay

2017 ◽  
Vol 751 ◽  
pp. 337-343 ◽  
Author(s):  
Chanchai Thongpina ◽  
Chaiwat Tippuwanan ◽  
Kwanchai Buaksuntear ◽  
Teerani Chuawittayawuta
Keyword(s):  
Mechanical Properties ◽  
Thermal Stability ◽  
Molecular Weight ◽  
High Molecular Weight ◽  
Mechanical Performance ◽  
Organic Peroxide ◽  
Degree Of Crystallinity ◽  
Poly Lactic Acid ◽  
Mechanical And Thermal Properties ◽  
Cloisite 30B

The thermal and mechanical properties of poly (lactic acid) blended with high molecular weight PEG, i.e. PEG1000 and PEG6000 were compared. The contents of PEG added were 10, 12.5 and 15 % by weight, with respect to PLA. The PLA/PEG blends were modified by addition of organic peroxide in order to induced crosslinking. Addition of organic modified montmorrillonite (Cloisite 30B, C30B) was also performed in order to modify mechanical performance of PLA/PEG blends. C30B was prepared via master batch in PLA. Morphology, crystallization, thermal stability and mechanical properties of the blends were investigated using SEM, DSC, TGA and universal testing macine, respectively. Morphology of cryogenic fracture surface showed smooth brittle surface. PEG1000 well plasticized PLA where as PEG6000 shows better thermal stability and mechanical properties. The presence of PEG induced PLA to perform cold crystallization. Tm in PLA was slightly changed whereas degree of crystallinity of PLA was improved by PEG but slightly decreased by peroxide. The thermal stability of PLA was enhanced with the addtion of PEG6000. The toughening of PLA was confirmed by the increment of elongation at break. The exfoliation of C30B was interfered by the crosslink PLA. Then tensile strength of PLA/PEG/C30B/Luperox101 was then suppressed. The optimum properties, in term of toughening and thermal stability, were found at PEG content of 10 % rather than 15% by weight, for both PEG1000 and PEG6000.

High-Performance Polyesters: Synthesis, Characterization, and Properties of Poly(P-Oxybenzoate)

2020 ◽  
Vol 992 ◽  
pp. 380-385
Author(s):  
A.I. Akhmetshina ◽  
L.K. Karimova ◽  
R.Ya. Deberdeev
Keyword(s):  
Thermal Stability ◽  
Molecular Weight ◽  
Thermal Properties ◽  
Ir Spectroscopy ◽  
High Performance ◽  
The Other ◽  
Transesterification Method

Poly (p-oxybenzoate) samples were synthesized via the esterification and the transesterification reactions. The structure of the obtained target products was investigated by IR spectroscopy and has revealed that these substances were oligomers. The transesterification method has facilitated the synthesis of higher molecular weight grades of the polymer. This resulted in enhanced thermal properties of polyester synthesized by transesterification (up to 340 °C). The other specimen has performed thermal stability up to 320 °C.

Thermal characteristics and physicomechanical properties of polyimidates

2019 ◽  
pp. 79-85
Author(s):  
D. M. Mognonov ◽  
O. Zh. Ayurova ◽  
O. V. Ilyina ◽  
V. N. Kornopoltsev ◽  
A. M. Mangadaev
Keyword(s):  
Thermal Stability ◽  
Molecular Weight ◽  
Plastic Deformation ◽  
Thermal Characteristics ◽  
Physicomechanical Properties ◽  
Hydrogen Energy ◽  
Strength Parameters ◽  
Mechanical Durability ◽  
Imidoyl Chlorides ◽  
Good Possibility

Polycondensation of equimolecular quantities of bis-imidoyl chlorides with bis-phenols in the environment of organic solvents synthesized imino-analogues of polyarylate – polyimidate. The received polymers are soluble in amide solvents, solvents of phenolic type and tetrachloroethane, and have significant interval between temperature of plastic deformation and thermal stability that presents a good possibility of their processing to products by modern industrial methods. The mechanical durability of the film materials of polyimidates is 65–90 MPa, obviously expressed dependence of the deformation-strength parameters on the value of the molecular weight of the polymer is observed. Despite the fact that polyimidates are of interest as intermediate polymer intermediates in the synthesis of polyaramides, they have their own complex of high thermal and deformation-strength characteristics, which makes them promising as adhesives, film materials, fibers and laminated plastics. One of the most important in practical terms properties of film materials based on polyimidates is their proton conductivity after doping in a solution of phosphoric acid, which allows the use of these polymers as membranes in the design of fuel cells of hydrogen energy.

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