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Title: The impact of post-radiation high-temperature shear grinding on the thermal and mechanical properties of polypropylene
The effect of input doses of 60Co γ-radiation from 80 to 12,000 kGy on the thermophysical properties and thermal stability of samples of polypropylene granules and powder obtained by high temperature shear grinding of irradiated granules, as well as on the tensile strength properties of a plate made from irradiated granules and their corresponding powders, was studied. The thermophysical properties of the powder are determined by the changes introduced by radiation into the initial polymer granules. The effects of radiation in air (environments with oxygen) were studied. Grinding redistributes oxygen-containing functional groups from the surface layer of irradiated granules throughout the entire volume of the obtained powder leading to the destruction of polymer chains as there is a component due to thermal destruction of radiolyzed polymer chains. High-temperature shear grinding of irradiated granules has a significant effect on the product powder, reducing its thermal stability but increasing the tensile strength of plates pressed from it at low absorbed doses. The current work shows that radiation treatment coupled with high temperature shear grinding could be a method for modifying the properties of polymers so that polypropylene waste can be processed for other applications.  more » « less
Award ID(s):
2205819
PAR ID:
10519153
Author(s) / Creator(s):
; ; ; ; ; ;
Publisher / Repository:
Elsevier
Date Published:
Journal Name:
Radiation Physics and Chemistry
Volume:
221
ISSN:
0969-806X
Page Range / eLocation ID:
111718
Subject(s) / Keyword(s):
Polypropylene granules and powders γ-irradiation High-temperature shear grinding DSC parameters TGA parameters Polymer degradation
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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