Pre‐transition phenomena in the crystallization and melting of flexible‐chain polymers

Abstract In isotactic polypropylene both crystallization and melting are always accompanied by a transition through the states characterized by the same structure with the presence of more or less large regions having the order of the liquid crystalline type. The appearance of these metastable structures is a consequence of the chain structure initially inherent in the macromolecules and should be expected in transitions of all isotactic polymers.