Supermolecular Structure, Free Volume, and Glass Transition of Needleless Electrospun Polymer Nanofibers

2021 ◽  
Author(s):  
Teggina Math Kotresh ◽  
Ramasubbu Ramani ◽  
Nirban Jana ◽  
Sathiadasan Minu ◽  
Ramakrishna Indu Shekar ◽  
...  
Keyword(s):  
Glass Transition ◽  
Free Volume ◽  
Supermolecular Structure ◽  
Polymer Nanofibers

Positron-annihilation studies of free-volume changes in the bulk metallic glassZr65Al7.5Ni10Cu17.5during structural relaxation and at the glass transition

1999 ◽  
Vol 60 (13) ◽  
pp. 9212-9215 ◽  
Author(s):  
C. Nagel ◽  
K. Rätzke ◽  
E. Schmidtke ◽  
F. Faupel ◽  
W. Ulfert
Keyword(s):  
Glass Transition ◽  
Positron Annihilation ◽  
Free Volume ◽  
Structural Relaxation ◽  
Volume Changes

scholarly journals A theoretical interpretation of free volume at glass transition

2017 ◽  
Vol 35 (11) ◽  
pp. 1415-1427 ◽  
Author(s):  
Yi-kun Ren ◽  
Yun-tao Li ◽  
Liang-bin Li
Keyword(s):  
Glass Transition ◽  
Free Volume ◽  
Theoretical Interpretation

Dielectric Relaxation at the Glass Transition as a Free Volume Process. II. A Continuous Distribution of Relaxation Times

1984 ◽  
Vol 125 (1) ◽  
pp. 409-419 ◽  
Author(s):  
A. Alegráa ◽  
J. M. Barandiarán ◽  
J. Colmenero
Keyword(s):  
Glass Transition ◽  
Dielectric Relaxation ◽  
Free Volume ◽  
Relaxation Times ◽  
Continuous Distribution

Liquids, Glasses, and the Glass Transition: A Free-Volume Approach

2007 ◽  
pp. 455-525 ◽  
Author(s):  
Gary S. Grest ◽  
Morrel H. Cohen
Keyword(s):  
Glass Transition ◽  
Free Volume

A molecular dynamics model of melting and glass transition in an idealized two-dimensional material I

1989 ◽  
Vol 329 (1608) ◽  
pp. 549-573 ◽  
Keyword(s):  
Molecular Dynamics ◽  
Thermal Expansion ◽  
Glass Transition ◽  
Free Volume ◽  
Dimensional Structure ◽  
Valuable Insight ◽  
Two Dimensional ◽  
Discrete Elements ◽  
Dynamics Model ◽  
Topological Features

In a preparatory study of structural relaxations and plastic flow in a two-dimensional idealized atomic glass, the process of melting and quenching through a glass transition has been studied by computer simulation using a molecular dynamics model. In this model, the transition from a solid to a melt was observed to take place when liquid-like structural elements composed of dipoles of five- and seven-sided Voronoi polygons percolate through the two-dimensional structure of distorted hexagons in the form of strings. Such dipoles constitute discrete elements of excess free volume within which liquid like behaviour is established in the sense of reduced cohesion or local elastic moduli. Upon quenching the melt, the percolation condition of liquid-like regions is retained for under-cooled melts between the melting point and a glass transition temperature below which the percolation condition is broken and the thermal expansion is sharply reduced. The simulation that has used empirical pair potentials characteristic of Cu and Zr has substantially underpredicted the melting and glass transition temperatures and overpredicted the thermal expansion of C u x Zr 1-x type glasses. These defects of the model can be partly attributed to the two-dimensional nature of the material, which stores larger concentrations of free volume than a corresponding three-dimensional material. In spite of these quantitative shortcomings, the model gives valuable insight into the topological features of the local atomic configurations at melting and upon vitrification.

Possible Experimental Equivalence of the Gibbs—DiMarzio and Free‐Volume Theories of the Glass Transition

1966 ◽  
Vol 45 (5) ◽  
pp. 1673-1678 ◽  
Author(s):  
Adi Eisenberg ◽  
Shogo Saito
Keyword(s):  
Glass Transition ◽  
Free Volume

Preparation and Properties of Internally Plasticized Bio-Based Film

2011 ◽  
Vol 236-238 ◽  
pp. 321-324
Author(s):  
Yu Zhi Xu ◽  
Ling Li ◽  
Chun Peng Wang ◽  
Fu Xiang Chu
Keyword(s):  
Thermal Analysis ◽  
Glass Transition ◽  
Fatty Acid ◽  
Supermolecular Structure ◽  
Chain Fatty Acid ◽  
Side Chain ◽  
Long Chain Fatty Acid ◽  
Cellulose Films ◽  
Similar Dynamic ◽  
Long Chain

This paper demonstrated acylation of cellulose with long chain fatty acid and internally plasticized cellulose films obtained by casting. The degrees of substitution (DS) and molar yields of fatty acid, Ts-Cl amounts and reaction time, and as well as the property of final products were studied. Partially derivative celluloses presented glass transition compared to starting cellulose. However, thermal behaviors of the internally plasticized esters with different DS were similar. Dynamic mechanical thermal analysis (DMTA) in tension mode revealed separate relaxations, denoted α and β, corresponding to the glass transition and side-chain melting processes, respectively. According to this, these longer chain esters (LCCEs) showed promise as internally plasticized cellulose films because the supermolecular structure of cellulose was significantly changed with the introduction of longer substituent.

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