Electronic excitation transfer as a probe of phase behavior in polymer composites

Deborah M. Hussey; Lukas Keller; Michael D. Fayer

doi:10.1117/12.273550

Abstract

We use time-resolved fluorescence anisotropy decay measurements to watch the complete process of phase- separation of molecularly mixed polymer blends. Fluorescent chromophores are covalently incorporated into one of the polymers in a blend, and electronic excitation transfer (EET) between these chromophores contributes to the rate of fluorescence anisotropy decay, which is measured using time- correlated single photon counting. Since the EET is highly sensitive to the chromophore distribution, this technique can reveal the single-chain structure and spatial distribution of polymer chains in the blend on the angstroms distance scale. Blend samples are studied both by rapidly quenching the phase-separating material below its glass- transition temperature and analyzing nanoscopic aggregates trapped in the sample, as well as by watching the process evolve in situ as the sample is heated above the glass transition and through the cloud-point. We find that not only the annealing temperature, but also the variable rate of heating can have a dramatic effect on the aggregation state of the blend at the nanoscopic level. Therefore, we may be able to influence those physical properties of the blend which depend on the aggregation state in specific ways. We examine the onset of phase separation while varying the molecular weight and chromophore content of one of the blend components and the blend composition.

Citation Download Citation

Deborah M. Hussey, Lukas Keller, Michael D. Fayer, "Electronic excitation transfer as a probe of phase behavior in polymer composites", Proc. SPIE 2980, Advances in Fluorescence Sensing Technology III, (7 May 1997); doi: 10.1117/12.273550; https://doi.org/10.1117/12.273550

ACCESS THE FULL ARTICLE

PERSONAL SIGN IN
Full access may be available with your subscription

Email or Username Forgot your username?

Password Forgot your password?

Show

Remember Email/Username on this computer

Remember Password

No SPIE account? Create an account
or Institutional Sign In via Shibboleth

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available

Members: $14.40

Non-members: $18.00 ADD TO CART

Show All Keywords

Keywords/Phrases

Search In:

Publication Years