Physical aging of molecular glasses studied by a device allowing for rapid thermal equilibration.

  title={Physical aging of molecular glasses studied by a device allowing for rapid thermal equilibration.},
  author={Tina Hecksher and Niels Boye Olsen and Kristine Niss and Jeppe C. Dyre},
  journal={The Journal of chemical physics},
  volume={133 17},
Aging to the equilibrium liquid state of organic glasses is studied. The glasses were prepared by cooling the liquid to temperatures just below the glass transition. Aging following a temperature jump was studied by measuring the dielectric loss at a fixed frequency using a microregulator in which temperature is controlled by means of a Peltier element. Compared to conventional equipment, the new device adds almost two orders of magnitude to the span of observable aging times. Data for the… 

Fast contribution to the activation energy of a glass-forming liquid

Monitoring how the system equilibrates after temperature jumps carried out just below the glass-transition temperature finds that the high-frequency shear modulus G∞ and the activation energy of the relaxation time are proportional throughout the approach to equilibrium, indicating that the relaxationTime is finite at all temperatures.

Cooling Rate Dependent Glass Transition in Thin Polymer Films and in Bulk

The glass transition is a well-known phenomenon marking the crossover from a liquid in metastable equilibrium to an out-of-equilibrium glass. In this chapter employing fast scanning calorimetry

Predicting nonlinear physical aging of glasses from equilibrium relaxation via the material time

The noncrystalline glassy state of matter plays a role in virtually all fields of materials science and offers complementary properties to those of the crystalline counterpart. The caveat of the

Single-Parameter Aging in the Weakly Nonlinear Limit

Physical aging deals with slow property changes over time caused by molecular rearrangements. This is relevant for non-crystalline materials such as polymers and inorganic glasses, both in production

Dynamics and thermodynamics of polymer glasses

  • D. Cangialosi
  • Materials Science
    Journal of physics. Condensed matter : an Institute of Physics journal
  • 2014
In this review, the peculiarities of the thermodynamics and dynamics of glass-forming polymers are discussed, with particular emphasis on those topics currently the subject of debate.

Communication: High pressure specific heat spectroscopy reveals simple relaxation behavior of glass forming molecular liquid.

The frequency dependent specific heat has been measured under pressure for the molecular glass forming liquid 5-polyphenyl-4-ether in the viscous regime close to the glass transition and it is shown that the ratio between the two time scales is independent of both temperature and pressure.



.alpha.-Relaxation in the Glass Transition Range of Amorphous Polymers. 1. Temperature Behavior across the Glass transition

The effect of the experimental liquid-glass transition on the dielectric relaxation of three amorphous polymers is investigated by means of frequency and time domain dielectric spectroscopies. By

α-Relaxation in the Glass-Transition Range of Amorphous Polymers. 2. Influence of Physical Aging on the Dielectric Relaxation

The influence of physical aging on the dielectric α-relaxation of three amorphous polymers is investigated by means of time domain dielectric experiments. It is found that the dielectric relaxation

Arrhenius-type temperature dependence of the segmental relaxation below Tg

In a recent paper DiMarzio and Yang [J. Res. Natl. Inst. Stand. Technol. 102, 135 (1997)] predicted that transport properties such as viscosity and diffusion coefficient do not follow the typical

Effect of annealing on the secondary relaxations in glasses

The dielectric loss in a rigid‐molecular glass (toluene–pyridine) and in poly(propylene oxide) has been measured from 50 to 2×105 Hz during the course of isothermal annealing at several temperatures.

Dynamics of glass-forming liquids. XIII. Microwave heating in slow motion.

Using time-resolved nonlinear dielectric relaxation measurements at fields as high as 450 kV/cm, the nonthermal effects of energy absorption are studied for simple and associating polar liquids in their supercooled state, explaining the incompatibility of heterogeneous dynamics with common physical aging observations.

A cryostat and temperature control system optimized for measuring relaxations of glass-forming liquids.

An experimental setup, including a cryostat and a temperature control system, has been constructed to meet the demands of measuring linear and nonlinear macroscopic relaxation properties of

The Adam-Gibbs equation and the out-of-equilibrium α relaxation of glass forming systems

The temperature dependence of the α-relaxation time out of equilibrium has been investigated by means of dielectric relaxation in a series of fragile glass formers including several polymers. The

Memory in an aging molecular glass

The dielectric susceptibility of the molecular liquid sorbitol below its calorimetric glass transition displays memory strikingly similar to that of a variety of glassy materials. During a temporary