Composition dependence of glass transition temperature and fragility. I. A topological model incorporating temperature-dependent constraints

2009 ◽  
Vol 130 (9) ◽  
pp. 094503 ◽  
Author(s):  
Prabhat K. Gupta ◽  
John C. Mauro
Keyword(s):  
Glass Transition ◽  
Transition Temperature ◽  
Glass Transition Temperature ◽  
Composition Dependence ◽  
Topological Model ◽  
Temperature Dependent

scholarly journals Determination of glass transition temperature using temperature dependent signal from a cryogenic photopyroelectric instrument

2019 ◽  
Vol 676 ◽  
pp. 7-12 ◽  
Author(s):  
Allen Mathew ◽  
Fabrice Goutier ◽  
Benoit Escorne ◽  
Abdelaziz Elass ◽  
Gérard Louis ◽  
...  
Keyword(s):  
Glass Transition ◽  
Transition Temperature ◽  
Glass Transition Temperature ◽  
Temperature Dependent ◽  
Dependent Signal

scholarly journals Review of Recent Developments of Glass Transition in PVC Nanocomposites

Polymers ◽  
2021 ◽  
Vol 13 (24) ◽  
pp. 4336
Author(s):  
Jolanta Tomaszewska ◽  
Tomasz Sterzyński ◽  
Aneta Woźniak-Braszak ◽  
Michał Banaszak
Keyword(s):  
Glass Transition ◽  
Transition Temperature ◽  
Glass Transition Temperature ◽  
Thermomechanical Analysis ◽  
Mechanical Analysis ◽  
Temperature Dependent ◽  
Scanning Calorimetry ◽  
Recent Developments ◽  
Dielectric Thermal Analysis ◽  
The Impact

This review addresses the impact of different nanoadditives on the glass transition temperature (Tg) of polyvinyl chloride (PVC), which is a widely used industrial polymer. The relatively high Tg limits its temperature-dependent applications. The objective of the review is to present the state-of-the-art knowledge on the influence of nanofillers of various origins and dimensions on the Tg of the PVC. The Tg variations induced by added nanofillers can be probed mostly by such experimental techniques as thermomechanical analysis (TMA), dynamic mechanical analysis (DMA), differential scanning calorimetry (DSC), and dielectric thermal analysis (DETA). The increase in Tg is commonly associated with the use of mineral and carbonaceous nanofillers. In this case, a rise in the concentration of nanoadditives leads to an increase in the Tg due to a restraint of the PVC macromolecular chain’s mobility. The lowering of Tg may be attributed to the well-known plasticizing effect, which is a consequence of the incorporation of oligomeric silsesquioxanes to the polymeric matrix. It has been well established that the variation in the Tg value depends also on the chemical modification of nanofillers and their incorporation into the PVC matrix. This review may be an inspiration for further investigation of nanofillers’ effect on the PVC glass transition temperature.

scholarly journals Topological model for Bi2O3-NaPO3 glasses. I. Prediction of glass transition temperature and fragility

2019 ◽  
Vol 521 ◽  
pp. 119534 ◽  
Author(s):  
Kuo-Hao Lee ◽  
Qiuju Zheng ◽  
Jinjun Ren ◽  
Collin J. Wilkinson ◽  
Yongjian Yang ◽  
...  
Keyword(s):  
Glass Transition ◽  
Transition Temperature ◽  
Glass Transition Temperature ◽  
Topological Model

Luminescence différée d'une solution organique vitreuse photoactivée et transition vitreuse

1977 ◽  
Vol 55 (13) ◽  
pp. 2517-2522 ◽  
Author(s):  
D. Ceccaldi
Keyword(s):  
Activation Energy ◽  
Relaxation Time ◽  
Glass Transition ◽  
Transition Temperature ◽  
Glass Transition Temperature ◽  
Kinetic Theory ◽  
Rise Time ◽  
Time Dependent ◽  
Glassy Matrix ◽  
Temperature Dependent

A general kinetic theory is used to explain the shapes of photoionized sample luminescence curves perturbed by thermal jumps (Δ ∼ 1 K, rise time ∼ 1 s). The samples studied are photoactivated organic vitreous solutions of TMPD/MCH 10−3 M and TMPD/3-MP 10−3 M. The experiments are performed within a temperature range (63–91 K) which includes the glass transition temperature Tg. It is shown that there is a slow diffusion of the trapped electrons towards the cation and competition between thermal detrapping and tunneling. The tunneling/thermal detrapping ratio Y is not time dependent during an isothermal luminescence and is only slowly temperature dependent if T ≤ Ty. Ty is very close to Tg. For T > Ty, Y decreases rapidly with T. The activation energy for thermal detrapping shows a maximum when the temperature reaches [Formula: see text] The glass transition temperature Tg may therefore be defined empirically as:[Formula: see text]Finally we obtain a glassy matrix relaxation time, τ, which decreases with T.

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