Blends of ethylene 1-octene copolymer synthesized by Ziegler-Natta and metallocene catalysts. II. Rheology and morphological behaviors

Citation
D. Rana et al., Blends of ethylene 1-octene copolymer synthesized by Ziegler-Natta and metallocene catalysts. II. Rheology and morphological behaviors, J APPL POLY, 76(13), 2000, pp. 1950-1964
Citations number
37
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Organic Chemistry/Polymer Science","Material Science & Engineering
Journal title
JOURNAL OF APPLIED POLYMER SCIENCE
ISSN journal
0021-8995 → ACNP
Volume
76
Issue
13
Year of publication
2000
Pages
1950 - 1964
Database
ISI
SICI code
0021-8995(20000624)76:13<1950:BOE1CS>2.0.ZU;2-W
Abstract
The rheological and morphological behaviors of commercially available three binary blends of ethylene 1-octene copolymer (EOC) regarding the melt inde x (MI), density and comonomer contents, one component made by the Ziegler-N atta and the other by the metallocene catalysts, were investigated to eluci date miscibility and phase behavior. Miscibility of the EOCs blend in a mel t state was related to the value of the MI, density, and comonomer content. If the comonomer contents are similar, then the melt viscosity is weight a verage value, otherwise it is positively or negatively deviated. The microt omed surface prepared by two different cooling processes-one is fast coolin g and the other is slow cooling-indicated that all the blends were not homo genous regardless the density, MI, and comonomer content. The Ziegler-Natta catalyzed EOCs exhibited bigger spherulitic diameter and larger ring space than those of the metallocene EOCs prepared by a cooling process. The blen ds consisting of similar MI showed banded spherulites with different diamet er, whereas the blend consisting of different MI and density takes place of explicit phase separation and phase inversion at 1 : 1 blend composition. The melt rheology appeared to influence the mechanical and film properties in the solid state. (C) 2000 John Wiley & Sons, Inc.