Glass transition and relaxations

Champion, D., Le Meste, M., and Simatos, D. 2000. Towards an improved understanding of glass transition and relaxations in foods Molecular mobility in the glass transition range. Trends Food Sci. Technol. 11, 41—55. 

Hutchinson, J. M. (1998). Characterising the glass transition and relaxation kinetics by conventional and temperature-modulated differential scanning calorimetry. Thermochimica Acta 324(1-2), 165-174. 

Sun Y, Zhang Z, Moon K-S, Wong CP (2004) Glass transition and relaxation behavior of epoxy nanocmnposites. J Polym Sci B Polym Phys 42(21) 3849-3858... 

Forrest, J.A., Jones, R.A.L. The glass transition and relaxation dynamics in thin polymer films. In Karim, A., Kumar S. (eds.) Polymer Surface Interfaces and Thin Films. World Scientific, Singapore (2000)... 

Several attempts have been made to superimpose creep and stress-relaxation data obtained at different temperatures on styrcne-butadiene-styrene block polymers. Shen and Kaelble (258) found that Williams-Landel-Ferry (WLF) (27) shift factors held around each of the glass transition temperatures of the polystyrene and the poly butadiene, but at intermediate temperatures a different type of shift factor had to be used to make a master curve. However, on very similar block polymers, Lim et ai. (25 )) found that a WLF shift factor held only below 15°C in the region between the glass transitions, and at higher temperatures an Arrhenius type of shift factor held. The reason for this difference in the shift factors is not known. Master curves have been made from creep and stress-relaxation data on partially miscible graft polymers of poly(ethyl acrylate) and poly(mcthyl methacrylate) (260). WLF shift factors held approximately, but the master curves covered 20 to 25 decades of time rather than the 10 to 15 decades for normal one-phase polymers. 

The mode coupling theory [11] has emerged from the hydrodynamics of liquids. This theory is able to explain the splitting of molecular mobility into relaxation modes that are frozen at the glass transition and molecular motion that is still possible below Tg. 

Chung, H.-J., Lee, E.-J., and Lim, S.-T. (2002). Comparison in glass transition and enthalpy relaxation between native and gelatinized rice starches. Carbohydr. Polym. 48, 287-298. 

The purpose of this paper is to establish the fundamental links between the glass transition, viscoelastic relaxation, and yield stress by investigating the relaxation processes in polymers. The relationship between temperature and relaxation time scale is represented by a shift factor (a). At temperature T... 

Chung, H. -J., Woo, K. -S., Lim, S. -T. (2004). Glass transition and enthalpy relaxation of eross-linked corn starches. Carbohydr. Polym., 55, 9-15. 

The kinetic character of the glass transition and the resulting non-equilibrium character of the glassy state are responsible for the phenomena of structural relaxation, glass transition hysteresis, and physical aging (Kovacs, 1963 Struik, 1978). 

LeBoeuf, E. J., and Weber, W. J., Jr. (2000a). Macromolecular characteristics of natural organic matter. 1. Insights from glass transition and enthalpic relaxation behavior. Environ. Sci. Technol. 34(17), 3623-3631. 

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