scholarly journals The Study of the Influence of Chemical Nature of Functional Groups in Oligomeric and Low--Molecular Modifiers on the Rheological Properties of the Epoxy Oligomer

2021 ◽  
Vol 15 (1) ◽  
pp. 53-60
Author(s):  
Elena Barabash ◽  
◽  
Yuriy Popov ◽  
Yuliya Danchenko ◽  
◽  
...  
Keyword(s):  
Rheological Properties ◽  
Structure Formation ◽  
Intermolecular Interaction ◽  
Functional Groups ◽  
Dynamic Viscosity ◽  
Chemical Nature ◽  
Epoxy Oligomer ◽  
Epoxy System ◽  
Intermolecular Interaction Energy ◽  
Low Concentrations

The influence of chemical nature of modifier functional groups on the level of intermolecular interactions in the system "epoxy oligomer ‒ modifier", as well as the structure formation and dynamic viscosity of epoxy oligomer has been studied in detail. Modifying additives in low concentrations contribute to an increase in the degree of structure formation of the epoxy system by increasing the intermolecular interaction between the associates of the epoxydiane oligomer. It was established that the strength of the formed coagulation structures depends both on the compatibility parameter of the modifiers and ED-20, and on their intermolecular interaction energy.

Dataset of noncovalent intermolecular interaction energy curves for 24 small high-spin open-shell dimers

2021 ◽  
Vol 154 (13) ◽  
pp. 134106
Author(s):  
Katarzyna Madajczyk ◽  
Piotr S. Żuchowski ◽  
Filip Brzȩk ◽  
Łukasz Rajchel ◽  
Dariusz Kȩdziera ◽  
...  
Keyword(s):  
Interaction Energy ◽  
Intermolecular Interaction ◽  
High Spin ◽  
Open Shell ◽  
Intermolecular Interaction Energy

β phase PVDF-hfp induced by mesoporous SiO2 nanorods: synthesis and formation mechanism

2015 ◽  
Vol 3 (15) ◽  
pp. 3708-3713 ◽  
Author(s):  
Du Yuan ◽  
Zibiao Li ◽  
Warintorn Thitsartarn ◽  
Xiaoshan Fan ◽  
Jiaotong Sun ◽  
...  
Keyword(s):  
Intermolecular Interaction ◽  
Functional Groups ◽  
Formation Mechanism ◽  
Surface Functional Groups ◽  
Β Phase ◽  
Synthesis Strategy ◽  
Effective Synthesis ◽  
Mesoporous Sio2

A simple and effective synthesis strategy is developed for electroactive β-PVDF-hfp where both intermolecular interaction and arrangement of surface functional groups operate.

RHEOLOGICAL PROPERTIES OF HUMIC SUBSTANCES OF PEAT AND BROWN COAL

2021 ◽  
pp. 169-174
Author(s):  
Ivan I. Lishtvan ◽  
Vera N. Aleinikova
Keyword(s):  
Rheological Properties ◽  
Humic Substances ◽  
Structure Formation ◽  
Humic Substance ◽  
Brown Coal ◽  
Oil Wells ◽  
Alkaline Media ◽  
Rheological Parameters ◽  
Acid Media ◽  
Brown Coals

Knowledge about structure and rheological peculiarities of drilling solutions and reagents applied for the proceeding of oil wells has significant value for the forecasting of oil wells drilling. The research results of the structure of the humic substances of peat and brown coals precipitated in different pH ranges from the standpoint of their ability to structure formation on the base of the rheological curves obtaining of the flow of their dispersions and determining of their rheological parameters in terms of their application in drilling practice are given in the article. It is established that during transition from fraction, beset into alkaline media (12.0–8.5) to fraction beset into acid media (5.0–2.0) the decrease of the rheological indicators of caustobiolate humic substance is occurred. Rheological curves of the flow of the disperse of caustobiolate humic substances of the fraction 1 and 2 are characterized for strong fossil structures, disperses of humic substances of the fraction 3 is for less strong coagulation structures. Less structured are humic substances of brown coal so that their use is preferable for the regulation of the structure and rheological peculiarities of drilling solutions.

scholarly journals Effect of Temperature and Used Ingredients on Rheological Parameters of Pancake Dough

2013 ◽  
Vol 16 (3) ◽  
pp. 63-66
Author(s):  
Peter Hlaváč ◽  
Monika Božiková
Keyword(s):  
Rheological Properties ◽  
Dynamic Viscosity ◽  
Kinematic Viscosity ◽  
Fat Content ◽  
Effect Of Temperature ◽  
Rheological Parameters ◽  
Rotational Viscometer ◽  
Two Samples ◽  
Dynamic And Kinematic Viscosity ◽  
Temperature Dynamic

Abstract This paper presents the selected rheological properties of pancake dough such as dynamic and kinematic viscosity and fluidity. The effect of used ingredients and temperature on rheological properties is investigated. Measurements were performed on three pancake dough samples. In two samples, there was used milk with a different fat content, and in the third sample, all ingredients were in a powder state. A digital rotational viscometer Anton Paar DV-3P was used for measuring the rheological properties. The principle of viscometer measurement is based on the dependence of sample resistance to probe rotation. Results of measurements are shown as graphical dependencies of rheological parameters on temperature. Exponential functions were used to express the dependencies of all rheological parameters on temperature. Dynamic and kinematic viscosity decreased, and fluidity increased with temperature. The highest values of dynamic viscosity were obtained for pancake dough from powder ingredients. A higher fat content of used milk caused higher values of dynamic viscosity.

scholarly journals Researche influence of holding time on the rheological properties of alumina slips containing with dispersing and hardening additives and the properties of corundum ceramics samples which made from them

2017 ◽  
Vol 117 ◽  
pp. 138-148
Author(s):  
V. V. Martynenko ◽  
V. V. Primachenko ◽  
K. I. Kushchenko ◽  
Yu. A. Krakhmal ◽  
Yu. Ye. Mishnyova ◽  
...  
Keyword(s):  
Rheological Properties ◽  
Dynamic Viscosity ◽  
Holding Time ◽  
Mechanical Mixing ◽  
Minimum Value ◽  
Coagulation Structure ◽  
Alumina Particles ◽  
Service Conditions ◽  
Thin Walled ◽  
Condensation Structure

The researches influence of holding time on the rheological properties of the slips and the properties of corundum ceramics samples based on alumina of the MARTOXID MR70 brand with dispersing and hardening additives (for casting thin-walled products) and only with the dispersing additive (for casting of thick-walled products) which made of them were carried out. The holding time has a significant effect on the rheological properties of the slips were established. The destruction of aggregates in initial alumina on particles were begining with increasing the holding time the slips to 24 hours as a result the dynamic viscosity of these slips decreases and reaches a minimum value. In the slips with combined additive (dispersing and hardening) with increasing the holding time more than 24 hours beginning the formation of a coagulation-condensation structure. In the slip with only a dispersing additive and in the slips without additive beginning the formation of a coagulation structure the dynamic viscosity of the slips increases and this process does not end at 672 hours. However, with a little mechanical mixing in all three slips their structure are fragile and easily almost completely destroyed and such slips are suitable for making quality products from them. The samples which made from the slips after a holding time of 24 hours and 720 hours have practically the same properties, so the increasing the holding time for more than 24 hours does not affect the properties of the samples. For making quality products the fresh slips are also suitable and it is necessary to choose the holding time of slips according to the size and configuration of products, their service conditions and production volumes. According to the electronicmicroscopic studies the formation a gel-like substance that envelops alumina particles and thereby prevents its settling in the slip which contains the hardening additive.

scholarly journals Crystal structures and Hirshfeld surface analyses of (E)-N′-benzylidene-2-oxo-2H-chromene-3-carbohydrazide and the disordered hemi-DMSO solvate of (E)-2-oxo-N′-(3,4,5-trimethoxybenzylidene)-2H-chromene-3-carbohydrazide: lattice energy and intermolecular interaction energy calculations for the former. Corrigendum

2019 ◽  
Vol 75 (12) ◽  
pp. 1952-1952
Author(s):  
Ligia R. Gomes ◽  
John Nicolson Low ◽  
James L. Wardell ◽  
Camila Capelini ◽  
José Daniel Figueroa Villar ◽  
...  
Keyword(s):  
Interaction Energy ◽  
Crystal Structures ◽  
Intermolecular Interaction ◽  
Lattice Energy ◽  
Hirshfeld Surface ◽  
Intermolecular Interaction Energy ◽  
Acta Cryst ◽  
Energy Calculations

In the paper by Gomes et al. [Acta Cryst. (2019), E75, 1403–1410], there was an error and omission in the author and affiliation list.

Study of the microstructure of low-molecular rubbers

2021 ◽  
Vol 87 (11) ◽  
pp. 26-32
Author(s):  
A. A. Pushkareva ◽  
O. A. Vozisova ◽  
M. A. Leuhina ◽  
L. L. Khimenko ◽  
A. N. Ilyin ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Glass Transition ◽  
Comparative Analysis ◽  
Low Temperature ◽  
Ir Spectroscopy ◽  
Rheological Properties ◽  
Polymer Chain ◽  
Epoxy Oligomer ◽  
Hydroxyl Groups ◽  
Structural Units

The oligomer microstructure, reflecting the configuration of the elementary units (cis-1,4-, trans-1,4-, and 1,2-) and their distribution order in the polymer chain, decisively affects the physicochemical and rheological properties of the oligomer. Parameters of microstructure-dependent transitions (glass transition) characterize the oligomer behavior under abnormal low-temperature conditions. We present the results of studying the microstructure of low-molecular rubbers. We determined the content of cis-1,4- and trans-1,4-structural links of poly-divinyl-isoprene-urethane-epoxy oligomer. The structure of polybutadiene HTPB-IV with terminal hydroxyl groups was analyzed using NMR and IR spectroscopy. A comparative analysis of the microstructure of the poly-divinyl-isoprene-urethane-epoxy oligomer and low molecular rubbers with a known content of structural units has been carried out. The obtained results can be used to obtain oligomers with the desired physicochemical and mechanical properties.

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