Monolayer properties of a fuzzy rod polymer: Poly(γ-stearyl α, L-glutamate)

Daewon Sohn, Hyuk Yu, Javier Nakamatsu, Paul S. Russo, William H. Daly

Research output: Contribution to journalArticle

17 Scopus citations

Abstract

Static and dynamic properties, and surface morphologies of monolayers at the air-water interface of a fuzzy rod polymer, poly(γ-stearyl α, L-glutamate), PSLG, have been examined by the Wilhelmy plate method for surface pressure, electrically induced capillary wave diffraction (ECWD), epi-fluorescence microscopy, and atomic force microscopy (AFM). The monolayers were first formed by spreading polymer solutions at the air-water interface and allowing the solvent to evaporate to obtain polymer films, i.e., spread monolayers. The surface mass density was varied by either successive additions of more solutions on a given surface area or step-wise compression of the surface barrier on a Langmuir trough. Surface pressure isotherms at 23-60°C were confirmed to be reversible and reproducible, and an abrupt change at approximately 60°C was observed, which is reported as the melting point of crystalline stearyl side chains. By AFM, the monolayer director n by surface alignment was confirmed as perpendicular to the compression direction and certain islands of departure from the monolayer state were visualized upon transferring the monolayers horizontally to silicon wafers. Macroscopic anisotropy in the surface alignment was probed by the electrocapillary waves propagated perpendicular (⊥) and parallel (//) to the director n; the surface tension anisotropy amount to about 7% difference, σ// < 0.07, where σ is the surface tension deduced from the wave propagation characteristics. Multidomain morphologies of the monolayers were imaged by epi-fluorescence microscopy and they were found to differ according to the method of monolayer mass density variation, i.e., the successive addition and step-wise compression.

Original languageEnglish
Pages (from-to)3025-3034
Number of pages10
JournalJournal of Polymer Science, Part B: Polymer Physics
Volume34
Issue number17
DOIs
StatePublished - 1996 Dec

Keywords

  • AFM
  • Electrocapillary wave diffraction
  • Epi-fluorescence
  • Fuzzy rods
  • Hairy rods
  • PSLG
  • Polymer monolayers

Fingerprint Dive into the research topics of 'Monolayer properties of a fuzzy rod polymer: Poly(γ-stearyl α, L-glutamate)'. Together they form a unique fingerprint.

  • Cite this