Polyethylene structural heterogeneity by thermal and rheological techniques

Recent advances in metallocene catalysts have created a rich set of structural variations for polyethylenes. Copolymers of unprecedented comonomer content and branching distribution have been commercialized. In this paper, we report progress in our laboratories in characterizing these parameters. Fo...

Full description

Saved in:
Bibliographic Details
Published inThermochimica acta Vol. 272; pp. 181 - 189
Main Authors Westphal, Stanley P., Ling, T.K., Woo, L.
Format Journal Article Conference Proceeding
LanguageEnglish
Published Amsterdam Elsevier B.V 20.01.1996
Elsevier Science
Subjects
Applied sciences
Exact sciences and technology
Metallocene catalyst
Organic polymers
Physicochemistry of polymers
Polyethylene
Properties and characterization
Structural heterogeneity
Structure, morphology and analysis
Structural heterogeneity
Polyethylene
Metallocene catalyst
EVA
Heterogeneity
Melting
Morphology
Ethylene propylene rubber
Property structure relationship
Crystallinity
Experimental study
Beta relaxation
Molecular relaxation
Online AccessGet full text

Cover

More Information
Summary:Recent advances in metallocene catalysts have created a rich set of structural variations for polyethylenes. Copolymers of unprecedented comonomer content and branching distribution have been commercialized. In this paper, we report progress in our laboratories in characterizing these parameters. For polymers of moderate to high crystallinity, differential scanning calorimetry (DSC) provided very good qualitative data, while temperature rising elution fractionation was more quantitative. However, when the crystallinity is low or near non-existent, a dynamic mechanical technique provided excellent quantiative data. A new method is introduced where the normalized beta relaxation linewidth is used to calculate the branching distribution. Good results for nearly totally amorphous polymers were obtained.
ISSN:0040-6031
1872-762X
DOI:10.1016/0040-6031(95)02614-2