Temperature-time analogy applied to thermorheologically complex polymer materials. 2. Mixtures of thermoplastic and thermosetting polymers (polymer-oligomer composites)

1978 ◽  
Vol 14 (3) ◽  
pp. 348-352 ◽  
Author(s):  
A. Ya. Gol'dman ◽  
G. Kh. Murzakhanov ◽  
O. A. Soshina
Keyword(s):  
Polymer Materials ◽  
Thermosetting Polymers ◽  
Complex Polymer ◽  
Temperature Time ◽  
Time Analogy

Temperature - time analogy for thermorheologically complex polymeric materials

1978 ◽  
Vol 13 (4) ◽  
pp. 516-522 ◽  
Author(s):  
A. Ya. Gol'dman ◽  
G. Kh. Murzakhanov ◽  
O. A. Soshina
Keyword(s):  
Polymeric Materials ◽  
Temperature Time ◽  
Time Analogy

scholarly journals Prolonged Thermal Relaxation of the Thermosetting Polymers

Polymers ◽  
2021 ◽  
Vol 13 (23) ◽  
pp. 4104
Author(s):  
Alexander Korolev ◽  
Maxim Mishnev ◽  
Nikolai Ivanovich Vatin ◽  
Anastasia Ignatova
Keyword(s):  
Elevated Temperatures ◽  
Thermal Relaxation ◽  
Polymer Structure ◽  
Polymer Materials ◽  
Prolonged Heating ◽  
High Entropy ◽  
Thermosetting Polymers ◽  
Entropy Parameter ◽  
Entropy Factor ◽  
Polymer Elasticity

The rigidity of structures made of polymer composite materials, operated at elevated temperatures, is mainly determined by the residual rigidity of the polymer binder (which is very sensitive to elevated temperatures); therefore, the study of ways to increase the rigidity of polymer materials under heating (including prolonged heating) is relevant. In the previous research, cured thermosetting polymer structure’s non-stability, especially under heating, is determined by its supra-molecular structure domain’s conglomerate character and the high entropy of such structures. The polymer elasticity modeling proved the significance of the entropy factor and layer (EPL) model application. The prolonged heating makes it possible to release adsorptive inter-layer bonds and volatile groups. As a result, the polymer structure is changing, and inner stress relaxation occurs due to this thermo-process, called thermo-relaxation. The present study suggests researching thermo-relaxation’s influence on polymers’ deformability under load and heating. The research results prove the significant polymer structure modification due to thermo-relaxation, with the polymer entropy parameter decreasing, the glassing onset temperature point (Tg) increasing by 1.3–1.7 times, and the modulus of elasticity under heating increasing by 1.5–2 times.

scholarly journals Adhesion-strength and tribotechnical properties of machine-building composite polymer coatings

2021 ◽  
Vol 264 ◽  
pp. 05032
Author(s):  
Soyibjon Negmatov ◽  
T Ulmasov ◽  
M Karshiyev ◽  
Z Makhammadjonov ◽  
O Abdulayev ◽  
...  
Keyword(s):  
Adhesion Strength ◽  
Adhesive Strength ◽  
Polymer Coatings ◽  
Machine Building ◽  
Polymer Materials ◽  
Tribotechnical Properties ◽  
Extreme Character ◽  
Relative Change ◽  
Temperature Time ◽  
Degree Of Filling

The article presents the results of studies of adhesive, strength and tribotechnical properties of composite polycaproamide polymer materials and coatings based on them for mechanical engineering purposes. It has been established that the relative change in the adhesion strength depends on the degree of filling in air and in argon has an extreme character passing through a maximum for coatings based on PCA with aluminum oxide, and for coatings made of PCA with copper oxide, it has a complex character. The formation of adhesive, strength, and tribotechnical properties of filled polycaproamide coatings was also studied. At the same time, it was found that by adjusting the temperature-time technological modes, it is possible to increase the adhesive, strength, and tribotechnical characteristics of composite polycaproamide coatings for machine-building purposes.

The conditions for the existence of a temperature - time analogy

1973 ◽  
Vol 6 (2) ◽  
pp. 196-200
Author(s):  
M. A. Koltunov ◽  
I. E. Troyanovskii
Keyword(s):  
Temperature Time ◽  
Time Analogy

scholarly journals Technologies for the Production of Machine-Building Composite Polymer Materials and Coatings Working in Contact With Raw Cotton

2021 ◽  
Vol 04 (11) ◽  
Author(s):  
Soyibdzhan Sodikovich Negmatov ◽  
◽  
◽  
Keyword(s):  
Industrial Waste ◽  
Dibutyl Phthalate ◽  
Polymer Coatings ◽  
Machine Building ◽  
Polymer Materials ◽  
Composite Polymer ◽  
Epoxy Oligomers ◽  
Polyethylene Polyamine ◽  
Thermosetting Polymers ◽  
Thermosetting Polymer

Based on numerous analyses of the research results, a technology was developed for obtaining the developed composite thermosetting polymer coatings based on thermosetting polymers-epoxy oligomers ED-20, FAED-20 and FEIS-30 plasticizer, dibutyl phthalate, polyethylene polyamine hardener and industrial waste and organomineral ingredients, as well as a technology for applying antifriction-strength composite polymer coatings for machine-building purposes on metal surfaces of products of various machines and mechanisms.

scholarly journals Heterogeneous Polymer Dynamics Explored Using Static 1H NMR Spectra

2020 ◽  
Vol 21 (15) ◽  
pp. 5176
Author(s):  
Todd M. Alam ◽  
Joshua P. Allers ◽  
Brad H. Jones
Keyword(s):  
Nmr Spectroscopy ◽  
1H Nmr ◽  
Dipolar Coupling ◽  
Polymer Materials ◽  
Dynamic Heterogeneity ◽  
Proton Proton ◽  
Dynamic Correlation ◽  
Thermosetting Polymers ◽  
Heterogeneous Polymer ◽  
The Impact

NMR spectroscopy continues to provide important molecular level details of dynamics in different polymer materials, ranging from rubbers to highly crosslinked composites. It has been argued that thermoset polymers containing dynamic and chemical heterogeneities can be fully cured at temperatures well below the final glass transition temperature (Tg). In this paper, we described the use of static solid-state 1H NMR spectroscopy to measure the activation of different chain dynamics as a function of temperature. Near Tg, increasing polymer segmental chain fluctuations lead to dynamic averaging of the local homonuclear proton-proton (1H-1H) dipolar couplings, as reflected in the reduction of the NMR line shape second moment (M2) when motions are faster than the magnitude of the dipolar coupling. In general, for polymer systems, distributions in the dynamic correlation times are commonly expected. To help identify the limitations and pitfalls of M2 analyses, the impact of activation energy or, equivalently, correlation time distributions, on the analysis of 1H NMR M2 temperature variations is explored. It is shown by using normalized reference curves that the distributions in dynamic activation energies can be measured from the M2 temperature behavior. An example of the M2 analysis for a series of thermosetting polymers with systematically varied dynamic heterogeneity is presented and discussed.

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