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Updated: Jun 23, 2026
09:08
A Simple and Efficient Protocol for the Catalytic Insertion Polymerization of Functional Norbornenes
Published on: February 27, 2017
Coherently aligned porphyrin-appended polynorbornenes
Hsian-Wen Wang1, Zhi-Chang Liu, Chih-Hsien Chen
1Department of Chemistry, National Taiwan University, Taipei, 106, Taiwan.
Chemistry (Weinheim an Der Bergstrasse, Germany)
|April 24, 2009
Summary
Synthesized porphyrin-appended polynorbornenes exhibit tunable photophysical properties influenced by pi-pi interactions. Alkyl-substituted polymers show strong exciton coupling and fluorescence quenching, while tetraaryl-substituted ones display ordered aggregation.
Area of Science:
- Polymer Chemistry
- Materials Science
- Photophysics
Background:
- Porphyrin-appended polynorbornenes are of interest for their unique photophysical properties.
- Understanding the role of pendant group interactions is crucial for controlling polymer behavior.
Purpose of the Study:
- To synthesize novel coherently aligned porphyrin-appended polynorbornenes.
- To investigate the influence of pi-pi interactions on polymer photophysics and stereoselective formation.
- To correlate structural modifications with fluorescence properties and aggregation behavior.
Main Methods:
- Synthesis of six different porphyrin-appended polynorbornenes via 5,6-endo-fused N-arylpyrrolidenonorbornenes.
- Spectroscopic analysis (UV-Vis, fluorescence) to determine photophysical properties.
- Time-resolved fluorescence measurements and Atomic Force Microscopy (AFM) for detailed characterization.
Main Results:
- Coherent alignment and pi-pi interactions are key to polymer properties.
- Alkyl-substituted porphyrins (2a-c) showed Soret band splitting, indicating strong exciton coupling.
- Tetraaryl-substituted porphyrins (2d-f) lacked Soret band splitting; polymers 2a-e exhibited significant fluorescence quenching, while 2f showed a reduced quantum yield.
- AFM revealed 2d formed ordered two-dimensional aggregates on graphite.
Conclusions:
- The study demonstrates a structure-property relationship in porphyrin-appended polynorbornenes.
- Pi-pi interactions and the degree of porphyrin substitution significantly impact exciton coupling, fluorescence, and aggregation.
- These findings offer insights for designing functional polymeric materials with tailored photophysical characteristics.
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