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Crystallization analysis fractionation (CRYSTAF) of poly(ethylene‐ co ‐1‐octene) made with single‐site‐type catalysts: A mathematical model for the dependence of composition distribution on molecular weight
Author(s) -
Soares João B. P.,
Monrabal Benjamin,
Nieto Jesús,
Blanco Javier
Publication year - 1998
Publication title -
macromolecular chemistry and physics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.57
H-Index - 112
eISSN - 1521-3935
pISSN - 1022-1352
DOI - 10.1002/(sici)1521-3935(19980901)199:9<1917::aid-macp1917>3.0.co;2-v
Subject(s) - fractionation , ethylene , molar mass distribution , crystallization , polymer , octene , catalysis , 1 octene , copolymer , polymer chemistry , chemistry , chemical composition , materials science , chemical engineering , analytical chemistry (journal) , chromatography , organic chemistry , engineering
A series of seven poly(ethylene‐ co ‐1‐octene) samples made with a single‐site‐type catalyst were analyzed by crystallization analysis fractionation (CRYSTAF). The samples have similar average copolymer compositions but differ in their average molecular weights. CRYSTAF results confirm the theoretical predictions of Stockmayer's distribution: the breadth of the chemical composition distribution is inversely proportional to the number average molecular weight for polymers made with single‐site‐type catalysts. Stockmayer's distribution was used to assess the instrumental peak broadening of CRYSTAF. An extension of this treatment for polyolefins made with multiple‐site‐type catalysts is proposed.