Coherently aligned porphyrin-appended polynorbornenes
| Autor: | Chih-Gang Chao, Chih-Hsien Chen, Tsong-Shin Lim, Zhichang Liu, Shern-Long Lee, Hsian-Wen Wang, Shou-Ling Huang, Tien-Yau Luh, Jian-Yuan Yu, Wunshain Fann, Chun-hsien Chen |
|---|---|
| Rok vydání: | 2009 |
| Předmět: |
chemistry.chemical_classification
Models Molecular Magnetic Resonance Spectroscopy Porphyrins Molecular Structure Photochemistry Exciton Organic Chemistry Quantum yield General Chemistry Polymer Chromophore Fluorescence Porphyrin Ring-opening polymerization Catalysis chemistry.chemical_compound Structure-Activity Relationship chemistry Moiety Plastics |
| Zdroj: | Chemistry (Weinheim an der Bergstrasse, Germany). 15(23) |
| ISSN: | 1521-3765 |
| Popis: | Six different kinds of coherently aligned porphyrin-appended polynorbornenes derived from 5,6-endo-fused N-arylpyrrolidenonorborneties have been synthesized. pi-pi interactions between the pendant groups are essential for dictating the photophysical properties of the polymers and the mechanism for the stereoselective formation of polymers. Splitting of the Soret band of polymers 2a-c, which have alkyl-substituted porphyrin pendant groups, suggests strong exciton coupling between chromophores. No splitting of the Soret band is observed for polymers 2d-f, which have tetraaryl substituents on the porphyrin moiety. Significant fluorescence quenching is found in polymers 2a-e, whereas only slightly reduced quantum yield is observed for 2f. Time-resolved fluorescence measurements, also indicate a similar trend. The AFM image of 2d on graphite shows aggregation to form a two-dimensional, ordered pattern. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Plný text