Journal ArticleDOI
Temperature dependence of liquid viscosity
TLDR
In this paper, a new dependence based on the free volume concept and cell-hole liquid theory is proposed, which permits linearization of the viscosity-temperature data in the range (Ti, Ti+1), where the Ti's are the liquid-liquid transition temperatures.Abstract:
Least squares programs were used to evaluate the correlation between recent experimental results and theoretical, semi-theoretical, or empirical relations between liquid viscosity and temperature. It was found that none of these describes the experimental dependence in the whole range of temperature. A new dependence based on the free volume concept and cell-hole liquid theory is proposed. The theory permits linearization of the viscosity-temperature data in the range (Ti, Ti+1), where the Ti's are the liquid-liquid transition temperatures. It was demonstrated that these transitions, both in small molecular and in polymeric liquids, occur in discrete steps: Ti = aiTg, where Tg is the glass transition temperature and the ai's are numerical parameters. Not all the transitions Ti were apparent in all liquids. Transition T2 = 1.26Tg was observed for most polymeric liquids. On the basis of thermal analysis it was demonstrated that the Ti's coincide with the temperatures at which small changes in the a...read more
Citations
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Journal ArticleDOI
Viscosity of glass-forming liquids.
TL;DR: This work presents a model offering an improved description of the viscosity–temperature relationship for both inorganic and organic liquids using the same number of parameters as VFT and AM, and casts doubt on the existence of a Kauzmann entropy catastrophe and associated ideal glass transition.
Journal ArticleDOI
Melt rheology of polymer blends
Leszek A. Utracki,M. R. Kanial +1 more
TL;DR: In this article, the rheological behavior of polymer blends is compared with that reported for emulsions, block polymers and homologous polymer blends, and the data obtained by the authors on the flow of poly(ethylene terephthalate)/Polyamide-6,6 are discussed in detail.
Journal ArticleDOI
Melt flow of polymer blends
TL;DR: In this paper, the results published during the last five years are compared with those obtained for simpler model systems: liquid mixtures, emulsions, and polymer blends, from the rheological point of view, the blends are divided into three groups: those where viscosity shows positive deviation from the log-additivity rule, PDB, those where the opposite effect is observed, NDB, and the remaining mixed behavior systems, PNDB.
Journal ArticleDOI
Viscosity of glass-forming systems
TL;DR: In this article, a review of the recent scientific progress in viscosity of glass-forming systems, including both the liquid and glassy states, is presented, where the authors compare the four models of the Vogel-Fulcher-Tammann (VFT) equation, Adam-Gibbs, Avramov-Milchev, and Mauro-Yue-Ellison-Gupta-Allan models.
Journal ArticleDOI
Dynamics and thermodynamics of the liquid state (T < Tg) of amorphous polymers
TL;DR: The liquid state behavior of the following atactic polymers has been reviewed: the alkyl and cycloalkyl methacrylates; polyisobutylene; polybutadiene, its random copolymers with styrene and acrylonitrile, and S-B diblocks; polystyrene; and poly-α-olefins C3, C5, and C6 as mentioned in this paper.
References
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Book
Viscoelastic properties of polymers
TL;DR: In this article, the authors describe the nature of Viscoelastic behavior of polymeric systems and approximate relations among the linear Viscoels and approximate interrelations among the Viscelastic Functions.
Journal ArticleDOI
Second‐Order Transition Temperatures and Related Properties of Polystyrene. I. Influence of Molecular Weight
Thomas Fox,Paul J. Flory +1 more
TL;DR: In this article, the second-order transition temperature, viscosity-temperature coefficient, and specific volume of fractionated polystyrenes containing diethylbenzene end groups are presented over wide temperature ranges.
Journal ArticleDOI
Studies in Newtonian Flow. II. The Dependence of the Viscosity of Liquids on Free‐Space
TL;DR: In this article, the viscosity of the liquid normal paraffins can be accurately defined as a simple function of relative free space except for values in the neighborhood of the freezing points of each compound.
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