In:
Macromolecular Symposia, Wiley, Vol. 240, No. 1 ( 2006-07), p. 114-122
Abstract:
A series of well defined polyethylene‐b‐polystyrene diblock copolymers (E x S y z , where x and y represent the composition in weight % and z the molecular weight in Kg/mol) has been synthesized in a wide composition range by sequential anionic polymerization. The molecular weight of the PE block was kept constant. A fractionated crystallization behavior was observed for the PE block within E 26 S 74 105 (PE cylinders) and E 11 S 89 244 (PE spheres). When the PE blocks form a continuous or percolated phase (PE, E 79 S 21 41 and E 53 S 47 51 ), a “classic” self‐nucleation behavior (where the usual three self‐nucleation domains are obtained) was observed. When the PE block is located within isolated microphases (having dimensions on the nanometer scale) and a fractionated crystallization was detected (E 26 S 74 105 and E 11 S 89 244 ), the fraction of crystals formed at higher temperatures exhibits a “classic” self‐nucleation behavior, while those crystals that crystallized at the largest supercooling (lower exotherms) can only be self‐nucleated at lower temperatures where annealing of unmolten material has already started. An unusual fractionated crystallization behavior for isolated, spherical PE microphases (E 11 S 89 244 ) is reported.
Type of Medium:
Online Resource
ISSN:
1022-1360
,
1521-3900
DOI:
10.1002/masy.200650815
Language:
English
Publisher:
Wiley
Publication Date:
2006
detail.hit.zdb_id:
2038549-3
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