Journal of Polymer Science Part A: Polymer Chemistry, Vol.46, No.2, 515-529, 2008
Preparation of MEH-PPV/nanosized titania hybrids via in situ sol-gel reaction of titanium alkoxide: Optical property
Homogenously dispersed organic (MEH-PPV)/inorganic (nanosized titania) hybrids were successfully synthesized. The method of preparation was based on a simple one-step in situ sol-gel technique using titanium isopropoxide (TIP) as the precursor. The key benefit of this preparation was that TIP interacted with both 2-chlorophenol and MEH-PPV, so that the degree of aggregation and phase separation could be kept to a minimum with a suitable recipe. MEH-PPV/TIP/H2O/2-chlorophenol of various weight ratios were synthesized to examine the morphology as well as optical properties of the MEH-PPV/TIP(titania) hybrid. The observation of MEH-PPV gelation and Fourier transform infrared results verified the interaction existing between MEH-PPV and TIP SEM photographs showed that TIP(titania) were homogenously dispersed in the MEH-PPV film if the hybrid solution was clear from the use of a suitable recipe. UV-vis absorption measurements showed that the addition of TIP decreased the conjugation length of MEH-PPV. A redshift in the photoluminescence (PL) emission was observed in almost all the hybrids in the solution state, because of the aggregation of MEH-PPV. However, it was found that spinning destroyed the aggregation of MEH-PPV, resulting in a blueshift in the PL emission of the hybrids. (C) 2007 Wiley Periodicals, Inc.