Related Experiment Video
Updated: Dec 26, 2025

Cooling Rate Dependent Ellipsometry Measurements to Determine the Dynamics of Thin Glassy Films
Published on: January 26, 2016
The Glass Transition Temperature of Monodispersed Polystyrenes and Their Binary Mixtures
Leo A Wall1, Roestamsjah2, Mary H Aldridge2
1Institute for Materials Research, National Bureau of Standards, Washington, D.C. 20234.
Abstract:
Glass transition measurements on monodispersed polystyrenes of different molecular weight and their binary mixtures result in the following conclusions: (a) the effect of molecular weight on the glass transitions of monodispersed samples satisfies the Fox and Flory equation written as T = T - A/M , with constant A = 0.84 × 10-5; (b) polymers of the same number average molecular weight with a broad distribution show lower glass transitions than the monodispersed; (c) the binary mixtures follow the Gordon-Taylor equation derived for copolymers, with constant k (experimental) 0.5.
More Related Videos
Related Concept Videos
Polymer Classification: Stereospecificity
Polymer Classification: Crystallinity
Crystalline domains are the regions where polymer chains are aligned in an orderly manner and held together in proximity by intermolecular forces. For example, chains in the crystalline domains of polyethylene and nylon are bound together by van der Waals...
Polymers: Molecular Weight Distribution
Molecular Weight of Step-Growth Polymers
As the step-growth polymerization involves step-wise condensation of monomers, the molecular weight also builds up eventually. Consequently, high molecular weight polymers are obtained at the late stages of the polymerization, where 99% of monomers have been consumed.
The extent of the...
Types of Step-Growth Polymers: Polyesters
Polyesters are commonly prepared from terephthalic acid and ethylene glycol; the crude product is known as poly(ethylene terephthalate) or PET. However, polyesters are synthesized industrially by transesterification of dimethyl terephthalate with ethylene glycol at 150 °C. The two reactants and the polymer...
Characteristics and Nomenclature of Copolymers

