PHASE-DIAGRAM OF A LIQUID-CRYSTAL SILOXANE POLYMER AT AIR-WATER-INTERFACE

We have carried out surface manometry and epifluorescence microscopic studies on a polymeric liquid crystal, siloxane polymer of 1-methyl pr opyl 4 (4'-hexyloxy benzoyloxy) benzoate, n similar to 40 at the air w ater interface. At room temperature, on compression, the usual liquid- expanded (LE) phase transforms to a different structure consisting of small bright domains. On further compression, these join to form stria tions which in turn change to a melted stripe structure. At 35 degrees C, on compression, the LE phase changes to a new structure which appe ars as large irregularly shaped bright domains. On cooling, these doma ins change to the melted stripe structure.