| Abstract
| - We report the results of a systematic orientation study onside-chain liquid crystallinepolymers (SCLCPs) mechanically stretched in different mesophases.Two representative polyacrylate-based SCLCPs were used. The study demonstrates that the macroscopicorientation of the mesogensreflects a direct alignment of the liquid crystalline domains asentities under the effect of a mechanicalfield. One important feature is that the alignment of differentmesophases results in different orientationdirections of the mesogens with respect to the mechanical stretchingdirection. On the basis of our results,it seems to be common that stretching SCLCPs in their smectic phasegives rise to a macroscopicorientation perpendicular to the stretching direction. When SCLCPsare stretched in a nematic phasecovering a wide temperature range, this orientation is achieved alongthe stretching direction. However,a perpendicular orientation can also be induced when SCLCPs arestretched in a nematic phase whichis only over a narrow temperature range (ca. 10 °C or fewer) beyond asmectic phase. A sharp inversionof the orientation direction often occurs when SCLCPs are stretched inthe mesophase transition regions.We show that the observed alignment behavior of the differentmesophases could be explained by assumingan alignment, always along the stretching direction, of the long axesof liquid crystalline domains.
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