A previous paper established the principle of

hairdressing

showing that polyethylene shish-kebab fibres can be reversibly transformed by appropriate preparation conditions between three morphologies, smooth fibres; fibres with closely spaced lamellar overgrowths; fibres with widely spaced lamellar overgrowths, where the spacing is sensitively affected by storage temperature (3). In the present paper this

hairdressing

work is extended to include the molten state. Three classes of morphology analogous to the three obtained from solution (although with certain minor differences) can be obtained by melting shish-kebabs at constant length, followed by quenching or isothermal crystallization. These

melt-hairdressed

fibres can be transformed back into shish-kebabs of typical solvent hairdressed appearance by the previously established procedures for solvent hairdressing. Thus all these works, following on from the trend established by Pennings (4), serve to highlight the fact that
all shish-kebabs acquire their external morphology at temperatures which are beneath those of the core formation during final cooling or storage and that
all external forms associated with a given core are interconvertible. On the molecular level these features highlight the intrinsically hairy nature of the core fibre as formed.
Key words Polyethylene - Shish-kebabs - melting - Recrystallisation -
Hairdressing
With 5 figures