The morphology, rheo-optical behavior, and mechanical relaxation properties were investigated for a series of three segmented copolyesters containing blocks of crystalline poly(tetramethylene terephthalate) and amorphous poly(tetramethylene ether). Transmission and replica electron micrographs show that if cast from a hot solution of 1,1,2-trichloroethane on a heated surface, all the samples show distinct spherulitic structures. Annealing appears to increase the lamellar thickness. On the other hand, casting from a solution of 1,1,2,2-tetrachloroethane produced a film that showed no evidence of the presence of spherulites, although microphase separation persists and crystallites appear to be randomly oriented in the amorphous matrix. Small-angle light-scattering experiments for trichloroethane-cast samples confirmed the existence of spherulites. Dynamic mechanical data of these copolyesters show three principal relaxation peaks. These are the melting peak of the poly(tetramethylene terephthalate) block, the primary glass transition peak of the poly(tetramethylene ether) block, and the local mode relaxations of both blocks at low temperatures. Annealing and casting from different solvents did not affect the relaxation behavior of these copolyesters.

A highly crosslinked amorphous polymer is produced by passing ethylene through a radio-frequency electric discharge. The morphology of plasma-polymerized ethylene is examined by replica electron microscopy. It is found that at low pressures and flow rates spherical powder particles are formed ranging in size between 0.2 and 1.2 μm. At high pressures and flow rates a film is formed. The role of the substrate on which the polymer is deposited has been investigated using chromium, Teflon, glass, and freshly cleaved mica as substrates. These materials are listed in order of increasing smoothness. From the electron micrographs it is observed that the surface structure of the substrate is reproduced in the plasma-polymerized films as long as the film is thin ([inverted lazy s] 0.5 μm). Thicker films produced by a longer exposure to the ethylene plasma are characterized by a surface which is smoother than that of the substrate.

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