Related Experiment Video
Updated: Jun 6, 2026

Monitoring the Effects of Illumination on the Structure of Conjugated Polymer Gels Using Neutron Scattering
Published on: December 21, 2017
Molecular weight dependence of emission intensity and emitting sites distribution within single conjugated polymer
Satoshi Habuchi1, Suguru Onda, Martin Vacha
1Department of Organic and Polymeric Materials, Tokyo Institute of Technology, 2-12-1-S8-44, Ookayama, Meguro-ku, Tokyo 152-8552, Japan. habuchi.s.aa@m.titech.ac.jp
Abstract:
We investigated exciton migration, trapping and emission processes occurring within a single conjugated polymer molecule by means of superresolution fluorescence localization microscopy. This methodology allowed us to locate the spatial distribution of emitting sites within single chains with nanometre precision. The study was done on individual poly[2-methoxy-5-(2'-ethyl-hexyloxy)-1,4-phenylene vinylene] (MEH-PPV) molecules with average molecular weights ranging from 215,000 to 1,440,000 and with narrow weight distributions. We found that the mean emission intensity increases proportionally to the polymer molecular weight. The localization experiments suggest that the emitting sites are distributed nearly uniformly within a single chain and that the sites are on average 10 nm apart, irrespective of the molecular weight of the polymer. Furthermore, spatial contours formed by all the combined emitting sites within one chain show elongated shapes, in agreement with a rod-like structure of MEH-PPV in a collapsed state.
More Related Videos
Related Concept Videos
UV–Vis Spectroscopy of Conjugated Systems
One of the factors influencing λmax is the extent of conjugation in the...
Polymers: Molecular Weight Distribution
Variables Affecting Phosphorescence and Fluorescence
Determination of Molar Masses of Polymers I
Molecular Weight of Step-Growth Polymers
As the step-growth polymerization involves step-wise condensation of monomers, the molecular weight also builds up eventually. Consequently, high molecular weight polymers are obtained at the late stages of the polymerization, where 99% of monomers have been consumed.
The extent of the...
Molecular Spectroscopy: Absorption and Emission

