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The green emission of poly(9,9′′‐dioctylfluorenyl‐2,7′′‐diyl), end‐capped by polyhedral oligomeric silsequioxanes, (PFO‐POSS) has been investigated by photoluminescence (PL) and photoexcitation (PE), gel permeation chromatography (GPC), and transmission Fourier transform infrared (FTIR) spectroscopy. The green emission is closely correlated with thermal oxidation degradation and crosslinking of the polymer and is enhanced by annealing at elevated temperatures. The green‐to‐blue emission intensity ratio, used to assess the emission properties of thin (90 nm) films, was 3.70, 4.35, and 1.54 for an air‐annealed film, its insoluble residue (crosslinked), and a film cast from its soluble portion, respectively. For thick (5–6 μm) film, the ratios are 13.33, 13.33, and 0.79, respectively. However, FTIR spectroscopy of thick films leads to the conclusion that the carbonyl‐to‐aromatic ring concentration ratio are 0.018, 0.015, and 0.032, respectively. Focusing on the recast films, the green emission is relatively low while the carbonyl concentration is relatively high. This suggests that the energy traps at crosslinked chains play an important role in green emission. It is likely that the crosslinking enhances the excitation energy migration and energy transfer to the defects by hindering chain segment twisting.

Micelles have been prepared from poly(acrylic acid)-graft-polystyrene by direct injection of a dioxane solution of the polymer into water containing various concentrations of NaCl. The size of the final micelle depends on the polymer concentration in the dioxane solution and the ionic strength of the aqueous phase. A relatively weak dependence of the micelle size on grafting density has been found. TEM images of these micelles reveal a unique “multicore” structure in which small spheres (presumably polystyrene) are associated with intervening polyacid chains that provide the aqueous solubility. It has been found that a very hydrophobic molecule (pyrene) can be solubilized efficiently in water by dissolving it with the polymer in dioxane prior to injection into the water phase. The morphology of the micelles containing pyrene is spherical, according to TEM.

C60 reacts with free radicals produced by AIBN thermal decomposition and/or propagating polystyrene radicals to form adducts or polymers with significantly modified optical properties. C60 competes with styrene for AIBN radicals acting as a free radical retarder that can be incorporated into the final polymer. In general, the weight percent of C60 in the polymer is increased at the expense of the polymer yield and molecular weight. The average number of C60 moieties per polymer is close to unity for the reaction conditions studied, but an analysis of size exclusion chromatographic traces suggests that multiple C60 moieties can be incorporated into the polymer.

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