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We have carried out time-resolved fluorescence quenching experiments, using pyrene derivatives as probes, on aqueous solutions of a hydrophobically modified alkali-soluble emulsion (HASE) polymer 1. This polymer is a 1:1 copolymer of ethyl acrylate and methacrylic acid, containing 1 mol % of a macromonomer with a C20H41 group at the end of an oligo(ethylene oxide) (EO32) spacer. The experiments we describe establish that the polymer 1 at full neutralization in water forms two different types of hydrophobic domains. When various pyrene derivatives are employed as probes, they partition between the two environments and exhibit different fluorescence decay times in the different types of domains. For experiments carried out at elevated probe concentration where excimer formation is important, proper analysis of the data is possible only if the solutions are deaerated. The data are fitted to a series of models invoking the presence of a single hydrophobic domain and two different hydrophobic domains. Only the latter model provides self-consistent results. From this model, we infer that the C20H41 groups form micelles with a mean aggregation number of 55 hydrophobes per micelle.

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Diamondoid molecules are cage-like, ultra stable and saturated hydrocarbons. The basic repetitive unit of the diamondoids is a ten-carbon tetracyclic cage system called "adamantane" (Fig. 1.1). They are called "diamondoid" because they have at least one adamantane unit and their carbon-carbon framework is completely or largely superimposable on the diamond lattice (Balaban and Schleyer, 1978; Mansoori, 2007). The diamond lattices structure was first determined in 1913 by Bragg and Bragg using X-ray diffraction analysis (Bragg and Brag, 1913). Diamondoids show unique properties due to their exceptional atomic arrangements. Adamantane consists of cyclohexane rings in "chair" conformation. The name adamantane is derived from the Greek language word for diamond since its chemical structure is like the three-dimensional diamond subunit as it is shown in Fig. 1.2. 1.2. Classification and Crystalline Structure of Diamondoids The first and simplest member of the diamondoids group, adamantane, is a tricyclic saturated hydrocarbon (tricyclo[3.3.1.1(3.7)]decane, according to the von Bayer systematic nomenclature).