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Proceedings of the Estonian Academy of Sciences

ISSN 1736-7530 (electronic)   ISSN 1736-6046 (print)
Formerly: Proceedings of the Estonian Academy of Sciences, series Physics & Mathematics and  Chemistry
Published since 1952

Proceedings of the Estonian Academy of Sciences

ISSN 1736-7530 (electronic)   ISSN 1736-6046 (print)
Formerly: Proceedings of the Estonian Academy of Sciences, series Physics & Mathematics and  Chemistry
Published since 1952
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The effect of modality on linear low-density polyethylene crystallization behaviour at high and very high supercoolings; pp. 53–57

(Full article in PDF format) doi: 10.3176/proc.2009.1.09


Authors

Triin Märtson, Andres Krumme, Veronika Gavrilkina, Anti Viikna

Abstract

Isothermal crystallization rates of uni- and bimodal linear low density polyethylenes having similar average molar mass and branching content were analysed at various temperatures in a very high supercooling range by means of a novel method – chip nanocalorimetry. At a particular crystallization temperature within the lower range of temperatures the bimodal material crystallized slower than the unimodal one, whereas at moderate supercooling temperatures bimodal polyethylene materials have earlier been reported to crystallize faster. Comparison to a high and moderate range of supercoolings was also made using an in-house built hot stage polarized light microscopy system. The difference gives evidence of a different crystallization mechanism caused by modality, which can have a strong impact on the application properties of the material.

Keywords

linear low-density polyethylene, crystallization rate, unimodal, bimodal, high supercooling, chip nanocalorimetry.

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Current Issue: Vol. 68, Issue 4, 2019




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