Differential initial fold surface ordering: a new morphological indicator

Abstract

Linear polyethylene crystallized isothermally on linear nuclei from blends with low density, branched polyethylene, cellulates at low concentrations with individual lead lamellae, typically ∼1 μm or so apart, advancing at a constant, faster rate than intervening lamellae whose growth is slowed by accumulated segregants. In these circumstances it is found that while initially all lamellae form with poor fold packing in {001} surfaces, only the faster-growing, lead lamellae continue to add molecules in this manner and eventually twist to relieve surface stress. For the majority, remaining lamellae growth slows and they soon adopt and retain {201} surfaces with their preferred fold packing. This not only illustrates how different lamellar components of texture can attain different habits with associated properties according to their respective growth rates, though with dominant lamellae determining the overall morphology, but in doing so, provides a new means to explore the intricacies of macromolecular self-organization.