Premium
A Single‐Gallery Model for the In Situ Production of Polyethylene‐Clay Nanocomposites
Author(s) -
Maneshi Abolfazl,
Soares João B. P.,
Simon Leonardo C.
Publication year - 2006
Publication title -
macromolecular symposia
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.257
H-Index - 76
eISSN - 1521-3900
pISSN - 1022-1360
DOI - 10.1002/masy.200651126
Subject(s) - materials science , polymerization , polyolefin , nanocomposite , in situ polymerization , polymer clay , polyethylene , post metallocene catalyst , coordination polymerization , polymer , chemical engineering , metallocene , composite material , polymer chemistry , radical polymerization , layer (electronics) , engineering
Abstract Polyolefin‐clay nanocomposites are finding many new applications because of their improved properties, such as high modulus, elevated scratch resistance and low gas permeability. Currently, these composites are produced by melt blending organically modified clay with polyolefins. The most challenging step in this process is the intercalation and exfoliation of the clay to produce a homogenously dispersed phase at the nanoscale. A promising alternative to melt blending is in‐situ polymerization, where the polymer is produced between the clay layers in the polymerization reactor. In‐situ polymerization of olefins with metallocene catalysts supported on clay can produce nanocomposites using conventional polymerization reactors, provided that the clay can be used as a support for the olefin polymerization catalyst. In this approach, the clay fulfills the functions of catalyst support and dispersed phase in the final nanocomposite. In this work, a mathematical model describing particle growth during in‐situ polymerization of ethylene with a metallocene catalyst supported on clay will be discussed. The model expands the approach of the multi‐grain model used in heterogeneous olefin polymerization to account for the layered structure of clays.