Molecular insights into hydrogen bonds in polyurethane/hindered phenol hybrids: evolution and relationship with damping properties

2014 ◽  
Vol 2 (22) ◽  
pp. 8545-8556 ◽  
Author(s):  
Kangming Xu ◽  
Fengshun Zhang ◽  
Xianlong Zhang ◽  
Qiaoman Hu ◽  
Hong Wu ◽  
...  
Keyword(s):  
Hydrogen Bond ◽  
Hydrogen Bonds ◽  
Md Simulation ◽  
Damping Properties ◽  
Property Variation ◽  
Damping Property ◽  
Hindered Phenol ◽  
The Relationship

By combining experiments and MD simulation, the relationship between hydrogen bond evolution and damping property variation of TPU was revealed.

Molecular insights into the damping mechanism of poly(vinyl acetate)/hindered phenol hybrids by a combination of experiment and molecular dynamics simulation

RSC Advances ◽  
2015 ◽  
Vol 5 (6) ◽  
pp. 4200-4209 ◽  
Author(s):  
Kangming Xu ◽  
Fengshun Zhang ◽  
Xianlong Zhang ◽  
Jiwei Guo ◽  
Hong Wu ◽  
...  
Keyword(s):  
Molecular Dynamics ◽  
Hydrogen Bond ◽  
Molecular Dynamics Simulation ◽  
Vinyl Acetate ◽  
Md Simulation ◽  
Dynamics Simulation ◽  
Property Variation ◽  
Damping Property ◽  
Hindered Phenol ◽  
The Relationship

By combining experiment and MD simulation, the relationship between hydrogen bond evolution and damping property variation of PVAc was revealed.

A Molecular Dynamics Simulation Study on the Relationship between Hydrogen Bond and Damping Properties of AO-70/NBR Composites

2017 ◽  
Vol 748 ◽  
pp. 29-34 ◽  
Author(s):  
Jing Zhu ◽  
Xiu Ying Zhao ◽  
Meng Song ◽  
Yue Han ◽  
Li Liu ◽  
...  
Keyword(s):  
Md Simulation ◽  
Type A ◽  
Dynamics Simulation ◽  
Butadiene Rubber ◽  
Damping Properties ◽  
Type B ◽  
Fractional Free Volume ◽  
Type C ◽  
Hindered Phenol ◽  
The Relationship

This work was try to study the number and types of hydrogen bonds (H-bonds) formed in hindered phenol AO-70/nitrile butadiene rubber (NBR) composites and their contributions to the damping properties by molecular dynamic (MD) simulation and experimental methods. MD simulation results showed that there were four types of H-bonds, namely, type A (AO-70) –OH...NC– (NBR) H-bonds in AO-70/NBR composites, type B (AO-70) –OH...O=C– (AO-70) H-bonds, type C (AO-70) –OH...OH–(AO-70) and D (AO-70) –OH...O–C– (AO-70) H-bonds, what's more, type A and type B H-Bonds formed more easily than others. Fourier transform infrared spectroscopy (FTIR) confirmed the existence of H-bonds. Meanwhile, the AO-70/NBR composites with AO-70 content of 109 phr had the largest number of H-bonds, smallest fractional free volume (FFV) and resulting in the optimistic damping performance of the composites.

Hindered phenol-mediated damping of polyacrylate rubber: effect of hydrogen bonding strength on the damping properties

2019 ◽  
Vol 39 (7) ◽  
pp. 642-652
Author(s):  
Renbo Ma ◽  
Xuewei Zhang ◽  
Chao Liu ◽  
Wei Wu
Keyword(s):  
Hydrogen Bond ◽  
Hydrogen Bonds ◽  
Bond Strength ◽  
Mechanical Analysis ◽  
Hydroxyl Group ◽  
Damping Properties ◽  
Scanning Calorimetry ◽  
Hydrogen Bond Strength ◽  
Hindered Phenols ◽  
Hindered Phenol

Abstract The loss factor (tanδ) and glass transition temperature (Tg) are two important parameters for evaluating damping properties. Hydrogen bonds (H bonds) play an important role in improving damping properties. In this work, the effect of the hydrogen bond strength and number on the damping properties was studied. Four hindered phenols with different steric hindrances were used to form hydrogen bonds with different strengths to mediate tanδ and Tg. Dynamic mechanical analysis (DMA), differential scanning calorimetry (DSC) and Fourier transform infrared spectroscopy (FTIR) showed that hindered phenol content lower than 38 wt% led to a linear increase in tanδ and Tg because of the formation of H bonds. The Kwei equation was used to explain the relationship between H bonds and tanδ. When the content was higher than 38 wt%, the small molecule-hindered phenols can be divided into two categories: those that can maintain a good miscibility, thus continuously increasing the tanδ, and those that make tanδ increase slowly or decrease because of poor miscibility. These results demonstrated that tanδ is closely related to both hydrogen bond strength and number. The degree of hindrance of the hydroxyl group determines the hydrogen bond strength, whereas the miscibility determines the number.

Study on the Relationship between the Hydrogen Bond and Damping Properties of Nitrile-Butadiene Rubber/Hindered Phenol Composites by Molecular Dynamics Simulation

2011 ◽  
Vol 410 ◽  
pp. 313-316 ◽  
Author(s):  
Tao Hu ◽  
Qiao Bo ◽  
Xiu Ying Zhao ◽  
Si Zhu Wu
Keyword(s):  
Hydrogen Bonds ◽  
Point Of View ◽  
Polymer Chains ◽  
Dynamics Simulation ◽  
Butadiene Rubber ◽  
Damping Properties ◽  
Fractional Free Volume ◽  
Nitrile Butadiene Rubber ◽  
Hindered Phenol ◽  
The Relationship

This work was try to study the relationship between the damping properties and the hydrogen bonds, fractional free volumes of nitrile-butadiene rubber (NBR)/hindered phenol (AO-80) composites from the microstructural point of view by combining the experimental and molecular simulation studies. The results indicated that the hydrogen bonds (HBs) were formed between AO-80 small molecules and NBR polymer chains. According to simulation results, because of the formed strongest HBs, highest binding energy and the smallest fractional free volume in the NBR/AO-80 composites with the blending ratio of 100/68, it contributed the maximum loss factor and highest modulus. It concluded that there was a suitable proportion of rubber blended with small hindered phenol molecules in the design of damping materials.

Influence of a Combined Low Dosage Gas Hydrate Inhibitor on Methane Hydrate Surface

2014 ◽  
Vol 1008-1009 ◽  
pp. 300-306
Author(s):  
Cui Ping Tang ◽  
Dong Liang Li ◽  
De Qing Liang
Keyword(s):  
Molecular Dynamics ◽  
Hydrogen Bond ◽  
Hydrogen Bonds ◽  
Gas Hydrate ◽  
Methane Hydrate ◽  
Md Simulation ◽  
Side Group ◽  
Large Space ◽  
Surface Molecules ◽  
Low Dosage

According to analysis of the gas hydrate cage and structure of the inhibitor and simulation of molecular dynamics, the interaction between GHI1 and hydrates was discussed. The structure analysis indicated the side group of PVP can insert into the open hydrate cage, and force the hydrate growing along the polymer chain, which results in a large space resistance and inhibits gas hydrate agglomerating. The results of MD simulation show GHI1 can damage the surface cage in hydrate lattice; the hydrogen and oxygen in GHI1 can form hydrogen bonds respectively with oxygen and hydrogen in hydrates, which makes the surface molecules of the cages unstable and distorts the cages; Synergist diethylene glycol ether increases strength and range of length of hydrogen bond.

scholarly journals Molecular Dynamics Simulation of VEGFR2 with Sorafenib and Other Urea-Substituted Aryloxy Compounds

2013 ◽  
Vol 2013 ◽  
pp. 1-7 ◽  
Author(s):  
Fancui Meng
Keyword(s):  
Molecular Dynamics ◽  
Hydrogen Bond ◽  
Molecular Dynamics Simulation ◽  
Hydrogen Bonds ◽  
Md Simulation ◽  
Binding Mode ◽  
Dynamics Simulation ◽  
Dynamics Simulations ◽  
Simulation Time ◽  
Dynamics Method

The binding mode of sorafenib with VEGFR2 was studied using molecular docking and molecular dynamics method. The docking results show that sorafenib forms hydrogen bonds with Asp1046, Cys919, and Glu885 of VEGFR2 receptor. Molecular dynamics simulation suggests that the hydrogen bond involving Asp1046 is the most stable one, and it is almost preserved during all the MD simulation time. The hydrogen bond formed with Cys919 occurs frequently after 6 ns, while the bifurcated hydrogen bonds involving Glu885 occurs occasionally. Meantime, molecular dynamics simulations of VEGFR2 with 11 other urea-substituted aryloxy compounds have also been performed, and the results indicate that a potent VEGFR2 inhibitor should have lower interaction energy with VEGFR2 and create at least 2 hydrogen bonds with VEGFR2.

Effects of chain polarity of hindered phenol on the damping properties of polymer-based hybrid materials: insights into the molecular mechanism

2020 ◽  
Vol 40 (5) ◽  
pp. 394-402
Author(s):  
Qiaoman Hu ◽  
Junhui Wang ◽  
Kangming Xu ◽  
Hongdi Zhou ◽  
Yue Huang ◽  
...  
Keyword(s):  
Hydrogen Bonding ◽  
Mechanical Analysis ◽  
Dynamics Simulation ◽  
Damping Properties ◽  
Structure Variation ◽  
Hydrogen Bonding Interactions ◽  
Ft Ir ◽  
Hindered Phenol ◽  
Damping Materials ◽  
The Relationship

AbstractFor hindered phenol (HP)/polymer-based hybrid damping materials, the damping properties are greatly affected by the structure variation of HPs. However, the unclear relationship between them limits the exploitation of such promising materials. Therefore, three HPs with different chain polarity were synthesized to explore the relationship in this paper. The structures of the HPs were firstly confirmed by Nuclear Magnetic Resonance Spectrum, Fourier Transform Infrared Spectroscopy (FT-IR) and X-ray Diffraction (XRD). For further prepared HP/polyurethane hybrids, FT-IR and XRD were also adopted to confirm the hydrogen bonding interactions and micromorphologies. And, Molecular dynamics simulation was further used to characterize the effects of polarity variation on the hydrogen bonding interactions and chain packing of the hybrids in a quantitative manner. Then, combined with dynamic mechanical analysis, the relationship between the chain polarity variation of the hindered phenols and the damping properties was established.

Electric and Damping Properties of PU Based IPNs-BaTiO3 Nanocomposites

2007 ◽  
Vol 336-338 ◽  
pp. 118-120
Author(s):  
Dong Yan Tang ◽  
Zheng Jin ◽  
Liang Sheng Qiang
Keyword(s):  
Dielectric Properties ◽  
Loss Factor ◽  
Synergistic Effects ◽  
Electric Properties ◽  
Damping Properties ◽  
Damping Property ◽  
Frictional Damping ◽  
Damping Loss Factor ◽  
The Relationship

(PU/UP IPNs)-BaTiO3 nanocomposites with different amounts of BaTiO3 nanopowder are prepared and polarized. The ferroelectric and dielectric properties are detected and the relationship between electric properties and damping properties are discussed in detail. Results indicate that the synergistic effects can be created successfully by elastic damping of polymer, frictional damping of BaTiO3, and piezoelectric damping of nanocomposites after poling. The nanocomposites increase the damping property evidently and sustain mostly ferroelectric and dielectric characters of inorganic phase. The introduction of BaTiO3 into IPNs decreases the resistivity, and this has advantages to enlarge the damping loss factor (tanδ).

scholarly journals On the Relationship between Hydrogen Bond Strength and the Formation Energy in Resonance-Assisted Hydrogen Bonds

Molecules ◽  
2021 ◽  
Vol 26 (14) ◽  
pp. 4196
Author(s):  
José Manuel Guevara-Vela ◽  
Miguel Gallegos ◽  
Mónica A. Valentín-Rodríguez ◽  
Aurora Costales ◽  
Tomás Rocha-Rinza ◽  
...  
Keyword(s):  
Hydrogen Bond ◽  
Hydrogen Bonds ◽  
Interaction Energy ◽  
Formation Energy ◽  
Function Analysis ◽  
Computational Cost ◽  
Intramolecular Interactions ◽  
Hydrogen Bond Interaction ◽  
Wave Function Analysis ◽  
The Relationship

Resonance-assisted hydrogen bonds (RAHB) are intramolecular contacts that are characterised by being particularly energetic. This fact is often attributed to the delocalisation of π electrons in the system. In the present article, we assess this thesis via the examination of the effect of electron-withdrawing and electron-donating groups, namely −F, −Cl, −Br, −CF3, −N(CH3)2, −OCH3, −NHCOCH3 on the strength of the RAHB in malondialdehyde by using the Quantum Theory of Atoms in Molecules (QTAIM) and the Interacting Quantum Atoms (IQA) analyses. We show that the influence of the investigated substituents on the strength of the investigated RAHBs depends largely on its position within the π skeleton. We also examine the relationship between the formation energy of the RAHB and the hydrogen bond interaction energy as defined by the IQA method of wave function analysis. We demonstrate that these substituents can have different effects on the formation and interaction energies, casting doubts regarding the use of different parameters as indicators of the RAHB formation energies. Finally, we also demonstrate how the energy density can offer an estimation of the IQA interaction energy, and therefore of the HB strength, at a reduced computational cost for these important interactions. We expected that the results reported herein will provide a valuable understanding in the assessment of the energetics of RAHB and other intramolecular interactions.

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