High-Resolution Observation of Crystal Transformation in Isotactic Polybutene-1 Single Crystals (STATES AND STRUCTURES-Polymer Condensed States)

Abstract

The crystal transformation in lamellar crystals of polybutene-1 grown from an amyl acetate solution was studied by cryogenic high-resolution transmission electron microscopy. The shape of the transformed trigonal (form-1) crystal domains in the surrounding tetragonal (form-2) crystal was successfully revealed. Along with the nucleation of "untwinned" form-1, the existence of another nucleation mechanism which creates "twinned" form-1 was suspected. The growth of form-1 crystal was thought to progress not stem by stem but by pulling in the molecular chains from the surrounding form-2, creating new stems of form-1. The shape of the form-1 domain was irregular, and no specific crystallographic direction along which the form-1 domain tends to grow was found.