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Updated: Jul 28, 2025

Ethylene Polymerizations Using Parallel Pressure Reactors and a Kinetic Analysis of Chain Transfer Polymerization
Published on: November 27, 2015
Molecular Simulations of Controlled Polymer Crystallization in Polyethylene
William S Fall1,2, Jörg Baschnagel1, Olivier Benzerara1
1Institut Charles Sadron, Université de Strasbourg and CNRS, 23 rue du Loess, 67034 Strasbourg Cedex, France.
Abstract:
Multilamella polymer crystals are grown from the melt for the first time, in molecular dynamics simulations of a united-monomer model, with in excess of 1500000 united-monomers. Two-component systems comprised of equal weight fractions of 2000 united-monomer long chains and 200 united-monomer short chains are considered, with varying numbers of short butyl branches placed along the long chains. Utilizing two different cooling protocols, continuous-cooling and self-seeding, drastically different multilamella structures are revealed, which depend heavily on the branch content and crystallization protocol used. By self-seeding, well-aligned multilamella crystals are grown, which more clearly reveal the subtle alterations an increasing number of branches create on the size and shape of the crystallites in the early stages of spherulite formation. Under continuous cooling, this observation is almost completely obscured. At maximum thickness, chain portions as long as 100 united-monomers (200 carbons) are extended inside the crystalline lamella.
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