title: Phase behavior of PCBM blends with different conjugated polymers.
abstract: In this work the phase behavior of [6,6]-phenyl C(61)-butyric acid methyl ester (PCBM) blends with different poly(phenylene vinylene) (PPV) samples is investigated by means of standard and modulated temperature differential scanning calorimetry (DSC and MTDSC) and rapid heat-cool calorimetry (RHC). The PPV conjugated polymers include poly(2-methoxy-5-(3',7'-dimethyloctyloxy)-1,4-phenylene vinylene) (MDMO-PPV), High T(g)-PPV which is a copolymer, and poly((2-methoxy-5-phenethoxy)-1,4-phenylene vinylene) (MPE-PPV). Comparisons of these PPV:PCBM blends with regioregular poly(3-hexyl thiophene) (P3HT):PCBM blends are made to see the different component miscibilities among different blends. The occurrence of liquid-liquid phase separation in the molten state of MDMO-PPV:PCBM and High T(g)-PPV:PCBM blends is indicated by the coexistence of double glass transitions for blends with a PCBM weight fraction of around 80 wt%. This is in contrast to the P3HT:PCBM blends where no phase separation is observed. Due to its high cooling rate (about 2000 K min(-1)), RHC proves to be a useful tool to investigate the phase separation in PPV:PCBM blends through the glass transition of these crystallizable blends. P3HT is found to have much higher thermal stability than the PPV samples.
authors.affiliation: Department of Polymer Science and Engineering, School of Chemical and Biological Engineering, University of Science and Technology Beijing, Beijing, P R China.
authors.forename: Jun
authors.initials: J
authors.lastname: Zhao
authors.forename: Sabine
authors.initials: S
authors.lastname: Bertho
authors.forename: Joke
authors.initials: J
authors.lastname: Vandenbergh
authors.forename: Guy
authors.initials: G
authors.lastname: Van Assche
authors.forename: Jean
authors.initials: J
authors.lastname: Manca
authors.forename: Dirk
authors.initials: D
authors.lastname: Vanderzande
authors.forename: Xiaoqing
authors.initials: X
authors.lastname: Yin
authors.forename: Jingdan
authors.initials: J
authors.lastname: Shi
authors.forename: Thomas
authors.initials: T
authors.lastname: Cleij
authors.forename: Laurence
authors.initials: L
authors.lastname: Lutsen
authors.forename: Bruno
authors.initials: B
authors.lastname: Van Mele