Abstract
Solid films of the liquid-crystal polycondensate of 80mol% p-acetoxybenzoic acid and 20mol% poly(ethylene terephthalate) were probed by exposures to controlled surfaces and electric fields and analysed by differential scanning calorimetry and X-ray diffraction. Films can develop some preferred backbone orientation after isothermal ageing of the mesophase and resolidification as a result of surface topography on confining walls. Mesophase ageing also results in solid films with greater structural order. Preferred backbone orientation is enhanced when solid films are heated to the liquid-crystalline state in an electric field and then resolidified. This is thought to result from the coupled effect of a pre-existing molecular field and dielectric alignment of the mesogenic chains. Interchain dipolar coupling and a biaxial nematic structure should be considered further as possible structural elements in these polymers.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 897-906 |
| Number of pages | 10 |
| Journal | Polymer |
| Volume | 28 |
| Issue number | 6 |
| DOIs | |
| State | Published - May 1987 |
Keywords
- electric field
- liquid-crystal polymer
- mesophase
- mesophase ageing
- surface
ASJC Scopus subject areas
- Organic Chemistry
- Polymers and Plastics
- Materials Chemistry