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A new scheme for the synthesis of phenylacetylene dendritic macromolecules is described which greatly facilitates the large-scale production of high molecular weight monodendrons. Simply by inverting the monomer protecting group scheme from B2AP to A2BP (where A = ArC=CH; B = Arl; Ap and Bp are protected versions of these groups), we show that the repetitive synthesis can be propagated through at least one higher generation on reaction scales 2 orders of magnitude greater than previously possible. Using this new scheme, we have prepared gram quantities of phenylacetylene monodendrons through generation four (I-Mbs-U-BuJm), in high yields. Possible reasons for the improvements are discussed. We furthermore show that the new route is amenable to a solid-phase convergent dendrimer synthesis which involves tethering the focal point monomer to an insoluble support. Preparation of phenylacetylene monodendrons by the solid-phase method is demonstrated through generation four, yielding monodendron products identical to those synthesized by solution methods. However, at generation four, coupling reactions using polymer supports can only be driven to completion with light loading of the focal point monomer.The solid-phase convergent method offers several advantages, especially in the synthesis of early generation monodendrons. \

We describe the electron paramagnetic resonance (EPR) study of dangling-bond sites (DBS) of plasmapolymerized films prepared from three unsaturated hydrocarbons, phenylacetylene, styrene and hex-3-yne. It has been shown that all the EPR spectra of DBS in such native films (before exposure to air) are much more intense than those after exposure to air. The DBS are quite stable at room temperature under anaerobic conditions, but their number begins to decrease towards a limiting value on heat treatment. However, when exposed to air the DBS decay rather rapidly; this decay tends to level off , indicating that there exist two different types of DBS, reactive and non-reactive. We discuss the difference in the nature of dissipation of DBS between oxidative and non-oxidative conditions.We also present the EPR spectral interpretations of the DBS and the reactions of several plasma-polymerized films previously reported.

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Physicochemical properties of a plasma-exposed glass surface under plasma conditions similar to those in plasma-initiated polymerization (brief plasma generation in a closed system) were investigated by SEM, X.P.S., wettability and electric conductivity measurements in order to elucidate how long-lived organic radicals can be trapped on such a glass surface.It was found that an invisible ultrathin polymer film was deposited on such a glass surface in the case of organic plasma exposure even under the above plasma conditions, although the physicochemical properties of the polymer film vary with the compounds submitted to plasma generation, and is largely different from those formed in the plasma-state polymerization.It has been suggested that the film can serve as an efficient host matrix for a variety of organic radicals which can be released under appropriate conditions so as to initiate the polymerization of various vinyl monomers.