The possibility of using the dissipation mode in high resolution atomic force microscopy is dem onstrated. By the dissipation mode we mean the dynamic mode in which the cantilever oscillates at a reso nance frequency and the oscillation amplitude serves as a signal of the feedback tracing a distance to the sur face. The possibility of obtaining molecular resolution when scanning in air is shown. The procedure of choosing the optimum scanning parameters is considered.

Block cooligomers of 2,6,7,10,11-pentapentyloxy-3-(3-acryloylpropyloxy)triphenylene and poly(tert-butyl acrylate) have been synthesized by the atom-transfer living radical polymerization. The preformed 3,6,7,10,11-pentapentyloxy-3-(3-acryloylpropyloxy)triphenylene block comprising eight monomer units was used as a macroinitiator with a fixed length, whereas the length of the poly(tert-butyl acrylate) block was varied through a change in the monomer-to-macroinitiator ratio. The microphase separation phenomenon has been established with DSC and X-ray diffraction. However, the sizes of discrete structures observed via transmission electron microscopy and atomic-force microscopy lie in the micron-size length (0.1-3.0 µ m). This fact is inconsistent with the molecular characteristics of individual blocks. It is proposed that the micron-sized structural elements are not true domain structures belonging to each phase but reflect the occurrence of aggregation in solution preceding formation of thin films.

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