Multiple glass transitions and local composition effects on polymer solvent mixtures

Jane E.G. Lipson, Scott T. Milner

Research output: Contribution to journalArticlepeer-review

32 Scopus citations

Abstract

Recent differential scanning calorimetry (DSC) results on polystyrene-solvent mixtures show two distinct glass transitions whose positions and widths vary with composition. Parallel work on the dynamic response in polymer blends has focused on how segmental mobilities are controlled by local composition variations within a "cooperative volume" containing the segment. Such variations arise from both chain connectivity and composition fluctuations. We account for both using a lattice model for polymer-solvent mixtures that yields the composition distribution around polymer and solvent segments. Insights from our lattice model lead us to simplified calculations of the mean and variance of local composition, both in good agreement with lattice results. Applying our model to compute DSC traces leads to an estimate of the cooperative volume, since a larger cooperative volume both reduces the biasing effect of connectivity, and narrows the composition distribution. Comparing our results to data, we are able to account for the composition-dependent broadening with a cooperative length scale of about 2.5 nm.

Original languageEnglish (US)
Pages (from-to)3528-3545
Number of pages18
JournalJournal of Polymer Science, Part B: Polymer Physics
Volume44
Issue number24
DOIs
StatePublished - Dec 15 2006

All Science Journal Classification (ASJC) codes

  • Condensed Matter Physics
  • Physical and Theoretical Chemistry
  • Polymers and Plastics
  • Materials Chemistry

Fingerprint Dive into the research topics of 'Multiple glass transitions and local composition effects on polymer solvent mixtures'. Together they form a unique fingerprint.

Cite this