Self-organized MEH-PPV domains in a TPU matrix and the consequences to the luminescence spectra

• Published in: Journal of applied polymer science Vol. 109; no. 6; pp. 3659 - 3664
• Main Authors: dos Reis Bombardi, André, Laureto, Edson, Duarte, José L, da Silva, Marco A.T, Dias, Ivan F.L, Patrício, Patrícia S.O, Silva, Glaura G, Cury, Luiz A
• Format: Journal Article
• Language: English
• Published: Hoboken Wiley Subscription Services, Inc., A Wiley Company 15-09-2008; Wiley
• Subjects: Applied sciences; conjugated polymer; Electrical, magnetic and optical properties; Exact sciences and technology; optical properties; Organic polymers; Physicochemistry of polymers; polymer blend; Properties and characterization; scanning electron microscopy; thermoplastic polyurethane; scanning electron microscopy; polymer blend; Polymer blends; Property composition relationship; Photoluminescence; thermoplastic polyurethane; Thermoplastic rubber; Phenylenevinylene derivative polymer; Experimental study; Heterogeneous mixture; Structure composition relationship; Polyurethane elastomer; Conjugated polymer; Domain structure; Morphology; Optical properties
• ISSN: 0021-8995; 1097-4628
• DOI: 10.1002/app.28491

Self-sustained cast films formed from heterogeneous blends of poly(2-methoxy-5-(2'-ethyl-hexyloxy)-1,4-phenylenevinylene) (MEH-PPV) conjugated polymer and thermoplastic polyurethane (TPU) were investigated by photoluminescence (PL) and scanning electron microscopy (SEM). A blue shift is observed for the pure electronic transition PL peak (E₀₀) with decreasing MEH-PPV concentration. The two clear shoulders in the PL spectra at higher energy than the E₀₀ peak appear due to the formation of small conjugation segments of the MEH-PPV molecules at the interface of the spherical MEH-PPV domains. This assumption and the origin of the blue shift were confirmed by correlating the average size of the MEH-PPV domains, observed from SEM images, and the analysis of the PL spectra at low temperatures.