Evaluating the molecular weight distribution of ultrahigh molecular weight polypropylene through rheology

نویسندگان

چکیده

This work investigates the possibility of obtaining molecular weight distribution (MWD) linear ultrahigh (UHMW) polypropylene (PP) through rheology. To this end, viscoelastic response a set UHMWPP samples is measured over largest possible frequency range. The terminal relaxation achieved by running creep experiments and converting compliance in dynamic moduli. A time–temperature concentration principle, recently validated for UHMW polyethylene, also applied to obtain sample with weight. rheological correlated gel permeation chromatography (GPC) results means mixing rule based on modulus. implementation such requires knowledge some material parameters governing stress polymer. Since they are unknown literature PP, estimated from comparison between spectra GPC distributions three lab-made UHMWPPs narrow polydispersity. Such then used as basis predict MWDs two large variability upon polydispersity assessed applying different PP lower weights, one polydyspersity another broad As curves available, first direct problem estimating MWD inverse data solved. An overall satisfactory agreement found calculated samples, both approach.

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ژورنال

عنوان ژورنال: Physics of Fluids

سال: 2023

ISSN: ['1527-2435', '1089-7666', '1070-6631']

DOI: https://doi.org/10.1063/5.0147911