Open AccessCrossover in dynamics of polymeric liquids: Back to T ll ?
Author(s) -
Kisliuk A.,
Mathers R. T.,
Sokolov A. P.
Publication year - 2000
Publication title -
journal of polymer science part b: polymer physics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.65
H-Index - 145
eISSN - 1099-0488
pISSN - 0887-6266
DOI - 10.1002/1099-0488(20001101)38:21<2785::aid-polb70>3.0.co;2-s
Subject(s) - glass transition , polystyrene , polymer , dynamic light scattering , spectral line , polymer chemistry , light scattering , thermodynamics , scattering , materials science , crossover , chemistry , physics , optics , composite material , nanotechnology , artificial intelligence , computer science , astronomy , nanoparticle
Light scattering spectra of two polymers, polyisobutylene (PIB) and polystyrene (PS), were analyzed in the broad frequency range at temperatures above the glass transition ( T g ). At high temperatures, the spectra followed the qualitative scenario suggested by mode‐coupling theory (MCT) of the glass transition. The crossover temperature ( T c ) was defined to be approximately 1.35 T g in PIB and approximately 1.15 T g in PS. At lower temperatures ( T < T c ), the light scattering spectra deviated strongly from the idealized MCT scenario. Different signs of the dynamic transition around T c are discussed. The difference between the suggested interpretation and an old idea of the liquid–liquid transition in polymeric liquids is stressed: we describe the transition as purely dynamic in nature. © 2000 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 38: 2785–2790, 2000