THE ROLE OF METASTABILITY IN PHASE-TRANSFORMATIONS - NEW POINTERS THROUGH POLYMER MESOPHASES

It is a long-standing experience, as expressed by Ostwald's Rule of St ages, that metastable phases can play a dominant role in phase transfo rmations. Presently the crystallisation of polymers, polyethylene in p articular, has thanks to the special mesomorphic features of one of it s phase variants, provided an example by which this old experience can be rationalised. In the course of it new perspectives have arisen in the held of polymer crystallisation in its own right, and beyond it ne w possibilities have opened up for the accounting for and hopefully co ntrol of polymorphism in crystal growth in wider generality.