Oligomers with structural elements of imidazolidinetrione obtained from oxamic acid and oxamide: polyurethane foams modified by structural elements of imidazolidinetrione

2015 ◽  
Vol 35 (1) ◽  
pp. 1-10 ◽  
Author(s):  
Iwona Zarzyka
Keyword(s):  
Thermal Stability ◽  
Polyurethane Foams ◽  
Thermally Stable ◽  
Structural Elements ◽  
Derivatives Of ◽  
Thermal Stability Of

Abstract Hydroxyalkyl derivatives containing oxamidoester and oxamide fragments have been separately obtained using oxamic acid, oxamide and alkylene carbonates. It has been proven that the presence of oxamidoester and oxamide structural fragments in oligomer structures is responsible for the thermal stability of these products. Rigid, thermally stable polyurethane foams were obtained with the use of oligomers with oxamidoestercarbamidoimide, carbamide, oxamidoester and oxamide groups as polyols components. The properties of these foamed materials were compared with each other and with the properties of reference foams. It was found that the polyurethane foams characterized by the best properties were obtained from hydroxypropyl derivatives of oxamide.

scholarly journals LNA units present in [RP-PS]-(DNA#LNA) chimeras enhance the thermal stability of parallel duplexes and triplexes formed with (2′-OMe)-RNA strands

RSC Advances ◽  
2020 ◽  
Vol 10 (38) ◽  
pp. 22370-22376
Author(s):  
Katarzyna Jastrzębska ◽  
Barbara Mikołajczyk ◽  
Piotr Guga
Keyword(s):  
Thermal Stability ◽  
Thermally Stable ◽  
Derivatives Of ◽  
Thermal Stability Of

3′-O-(2-Thio-1,3,2-oxathiaphospholane) derivatives of 5′-O-DMT-LNA-nucleosides were used to prepare P-stereodefined (RP-PS)-DNA#LNA chimeras, which form thermally stable parallel complexes with (2′-OMe)-RNA matrices.

Thermal Reactions of Bisazides in Resists Containing Double Bonds

1986 ◽  
Vol 76 ◽  
Author(s):  
C. A. Pryde
Keyword(s):  
Thermal Stability ◽  
Ir Spectroscopy ◽  
Thermal Degradation ◽  
Significant Degree ◽  
Thermally Stable ◽  
Double Bonds ◽  
Thermal Reactions ◽  
Thermal Addition ◽  
Derivatives Of ◽  
Thermal Stability Of

ABSTRACTDerivatives of 2,6-bis(4-azidobenzylidene) cyclohexanone are frequently used as photosensitizers in photoresists. These compounds are generally considered to be quite thermally stable. However, there have been reports of thermal degradation occurring at temperatures as low as 60'C.Experiments done here suggest that the thermal stability of the azide is adversely affected by the presence of unsaturated material in the formulation. Data from IR spectroscopy show that, by itself, 2,6-bis(4-azidobenzylidene) 4-methylcyclohexanone is thermally stable in a polyamic acid film at 75–80° C. However, addition of a monomeric aminoacrylate to the formulation results in a significant decay in the absorption of the azide moiety in just a few hours at these same temperatures. This decay is attributed to reaction of the sensitizer with the acrylate double bonds. In a thick film, which might require a 1–2 hour prebake, this thermal addition could result in a significant degree of crosslinking and thus to decreased contrast in the final pattern.

Preparation and Pyrolysis of Stereoisomeric Bromobicyclo[n.1.0]alkanes ( n = 6, 8 , 10)

1987 ◽  
Vol 42 (4) ◽  
pp. 489-494 ◽  
Author(s):  
Eckehard V. Dehmlow ◽  
Roland Kramer
Keyword(s):  
Thermal Stability ◽  
Gas Phase ◽  
Condensed Phase ◽  
Secondary Products ◽  
Gas Phase Reactions ◽  
Stereoselective Reduction ◽  
Derivatives Of ◽  
Thermal Stability Of

Abstract The title compounds la-3c were prepared by stereoselective reduction of the respective dibromides. Pyrolysis gave allylic bromides (8, 9, 11) as primary and dienes (10, 12) as secondary products. Product ratios were independent of the stereochemistry of the starting materials. No differences of the rearrangement rates of the stereoisomers were observed in gas phase reactions of the derivatives of bicyclo[6.1.0]- and bicyclo[8.1.0]alkanes. With the larger bicyclo[10.1.0] derivatives, however, distinct differences in the thermal stability of cis-trans-isomers4c/5c or 2c/3c were found in condensed phase.

scholarly journals The Thermal Stability of Aviation Fuel

1984 ◽  
Author(s):  
J. S. Mills ◽  
F. R. Edwards
Keyword(s):  
Thermal Stability ◽  
Research Tool ◽  
Aviation Fuel ◽  
Engine Oil ◽  
Thermally Stable ◽  
Fuel System ◽  
Flow Rates ◽  
Aircraft Fuel ◽  
Oil Cooler ◽  
Thermal Stability Of

The propensity of aviation turbine fuels to produce deposits in the oil-cooler and filter sections of aircraft fuel systems has been examined using a rig that simulates the fuel system of an aircraft and which employs realistic flow rates. All the fuels examined were found to be thermally stable up to temperatures in excess of those currently attained in engine oil coolers. Comparison with results obtained with the JFTOT indicates that this is not suited for use as a research tool.

Synthesis and thermal stability of perovskite alkali metal strontium borohydrides

2016 ◽  
Vol 45 (2) ◽  
pp. 831-840 ◽  
Author(s):  
Kasper T. Møller ◽  
Morten B. Ley ◽  
Pascal Schouwink ◽  
Radovan Černý ◽  
Torben R. Jensen
Keyword(s):  
Thermal Stability ◽  
Alkali Metal ◽  
Thermally Stable ◽  
Perovskite Type ◽  
Thermal Stability Of

Synthesis of new thermally stable perovskite-type metal strontium borohydrides, MSr(BH4)3 (M = K, Rb, Cs).

Thermal stability of polymers based on vinyl derivatives of silicon

1966 ◽  
Vol 8 (5) ◽  
pp. 976-981 ◽  
Author(s):  
N.S. Nametkin ◽  
N.A. Nechitailo ◽  
S.G. Durgar'yan ◽  
V.S. Khotimskii
Keyword(s):  
Thermal Stability ◽  
Vinyl Derivatives ◽  
Derivatives Of ◽  
Thermal Stability Of

Thermal stability of polyamides based on derivatives of bis-(p-aminophenyl) methane

1978 ◽  
Vol 20 (10) ◽  
pp. 2487-2493
Author(s):  
Yu.N. Sazanov ◽  
G.N. Fedorova ◽  
L.M. Shcherbakova ◽  
G.I. Nosova
Keyword(s):  
Thermal Stability ◽  
Derivatives Of ◽  
Thermal Stability Of

scholarly journals The Modification of Polyurethane Foams Using New Boroorganic Polyols (II) Polyurethane Foams from Boron-Modified Hydroxypropyl Urea Derivatives

2014 ◽  
Vol 2014 ◽  
pp. 1-9
Author(s):  
Iwona Zarzyka
Keyword(s):  
Thermal Stability ◽  
Boric Acid ◽  
Water Absorption ◽  
Propylene Carbonate ◽  
Dimensional Stability ◽  
Polyurethane Foams ◽  
Urea Derivatives ◽  
Nitrogen Ratio ◽  
Thermal Stability Of

The work focuses on research related to determination of application possibility of new, ecofriendly boroorganic polyols in rigid polyurethane foams production. Polyols were obtained from hydroxypropyl urea derivatives esterified with boric acid and propylene carbonate. The influence of esterification type on properties of polyols and next on polyurethane foams properties was determined. Nitrogen and boron impacts on the foams’ properties were discussed, for instance, on their physical, mechanical, and electric properties. Boron presence causes improvement of dimensional stability and thermal stability of polyurethane foams. They can be applied even at temperature 150°C. Unfortunately, introducing boron in polyurethanes foams affects deterioration of their water absorption, which increases as compared to the foams that do not contain boron. However, presence of both boron and nitrogen determines the decrease of the foams combustibility. Main impact on the decrease combustibility of the obtained foams has nitrogen presence, but in case of proper boron and nitrogen ratio their synergic activity on the combustibility decrease can be easily seen.

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