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Langmuir-Blodgett films of mesomorphic side-chain polymethacrylates are investigated from the point of view of their phase change versus temperature via X-ray and neutron reflectivity. Upon heating, “thick” films undergo an irreversible transition towards the well known smectic Al lamellar phase. In contrast a bilayer deposited onto a solid substrate appears to be very stable upon annealing. Such a behaviour is believed to induce an epitaxial mechanism when cooling “thick” Rims from the isotropic melt phase.

In the liquid state, water molecules tend to be surrounded tetrahedrally by four other molecules. This tendency gives rise to a three-dimensional open network which is a feature of most of the solid phases: in addition to the many polymorphic crystalline forms presently known, there exist glassy and amorphous ices with unique hydrogen-bonded structures. In this paper, we briefly review the structural properties of the crystalline and non-crystalline phases including the more recent data quoted in the literature.

Within the liquid crystalline domain, dihydroxysilicon(IV) octakis(dodecyloxymethyl) phthalocyanine is polycondensed to give a distribution of polysiloxanes. These latter form a mesophase with lamellar order. For the first time polycondensation has been carried out in a columnar mesophase and a new type of oligomeric mesogen has been obtained. The term spinal columnar liquid crystal is proposed to designate such a mesophase.