Format:
Online-Ressource
ISSN:
1521-3900
Content:
Abstract: Summary: Sorption experiments of ethylene and propylene in different polypropylene powder samples, both homopolymer and heterophasic copolymers with different rubber content, have been carried out in a high‐pressure magnetic suspension balance at 10 bars pressure and 70 °C. The gross solubilities measured can be well correlated with the rubber content of the polymer samples. Solubility of ethylene and propylene in the rubber phase differ from solubility in the amorphous fraction of the homopolymer, especially the concentration ratio of propylene to ethylene differs significantly between rubber phase and amorphous fraction of the homopolymer. From the slope of monomer uptake, information on kinetics of mass‐transfer can be gained. No significant differences were observed in terms of mass‐transfer for ethylene and propylene. With increasing rubber content, effective diffusion coefficients increased slightly. By combined sorption studies with powder samples and compressed films, information about both effective diffusion coefficients and the effective length scale of diffusion could be gained. It could be shown, that the particle radius is not the characteristic length of diffusion in the studied powder samples. Mass transfer of nearly all samples could be described by a constant diffusion length of 120 to 130 µm, independently on particle size. This indicates that the effective scale of diffusion in polymer particles is in between microparticle and macroparticle scale used in classical particle modeling.
In:
volume:259
In:
number:1
In:
year:2007
In:
pages:327-336
In:
extent:10
In:
Macromolecular symposia, Weinheim : Wiley-VCH, 1986-, 259, Heft 1 (2007), 327-336 (gesamt 10), 1521-3900
Language:
English
DOI:
10.1002/masy.200751337
URN:
urn:nbn:de:101:1-2023080206461483782185
URL:
https://doi.org/10.1002/masy.200751337
URL:
https://nbn-resolving.org/urn:nbn:de:101:1-2023080206461483782185
URL:
https://d-nb.info/1297962419/34
URL:
https://doi.org/10.1002/masy.200751337
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