Preparation and Optical Limiting Properties of Polyurethane Containing Long Conjugated Chromophores

Two functional polyurethanes (P1 and P2) bearing a large π electron conjugated chromophoric pendant were synthesized and characterized by FT‐IR, ¹H‐NMR and UV‐Vis absorption spectra. Their optical limiting properties were evaluated. The results show that P1 and P2 show novel optical limiting properties, which are assigned to a long π electron conjugated chromophoric pendant. It was found that their optical limiting properties were affected simultaneously by solution concentration and P2 displays a better optical limiting property than P1 at the same solution transmittance, although that P1 has larger χ⁽³⁾ (4.28×10⁻¹¹ esu) than P2 (0.87×10⁻¹¹ esu), and their optical limiting mechanism is investigated.

Keywords:

• optical limiting
• polyurethanes
• synthesis
• NLO

5 Acknowledgements

This research was financially supported by the National Natural Science Fund of China (Grant Nos. 90606011 and 50472038), Program for New Century Excellent Talents in University (NCET‐04‐0588), the outstanding Youth Fund of Anhui Province (Grant No. 04044060), and the Award for High Level Intellectuals (Grant No. 2004Z027) from Anhui Province.