Nonlinear time-dependent behavior of rheodictic polymers

ǂa ǂtheoretical and experimental investigation

Alen Oseli (Author), Mohor Mihelčič (Author), Matic Šobak (Author), Lidija Slemenik Perše (Author)

Abstract

The present study examined the nonlinear time-dependent behavior of rheodictic polymers, a class of noncrosslinked materials that exhibit flow. Such behavior was addressed with extended Schapery’s nonlinear viscoelastic model by introducing new physical quantities, i.e., the flow term and corresponding nonlinear shift parameter . While portrays irrecoverable deformation, depicts a nonlinear contribution to flow acceleration. This theory was accompanied by analytical and experimental methodologies for identifying all the parameters in the linear and nonlinear viscoelastic domains. Predictions of long-term time-dependent behavior (in shear) at various stress states show excellent agreement with the experimental data, i.e., within error, obtained for polycarbonate at . Surprisingly, the newly introduced indicates that flow retardation occurs with increasing stress, implying that a highly deformed entangled system hinders molecular reptation/disentanglement. Nevertheless, the proposed extension of Schapery’s nonlinear viscoelastic model not only allows accurate predictions of the nonlinear time-dependent behavior of rheodictic polymers but also enables a detailed outlook on the underlying molecular mechanisms under severe environmental and loading conditions.

Keywords

reodiktični polimeri;nelinearno vedenje;časovno odvisne mehanske lastnosti;proces lezenja;Schaperijev nelinearni model;rheodictic polymers;nonlinear behavior;time-dependent mechanical properties;creep process;Schapery’s nonlinear model;

Data

Language:	English
Year of publishing:	2024
Typology:	1.01 - Original Scientific Article
Organization:	UL FS - Faculty of Mechanical Engineering
UDC:	620.17:678.7
COBISS:	203185923
ISSN:	1873-2348
Views:	27
Downloads:	2
Average score:	0 (0 votes)
Metadata:

Other data

Secondary language:	Slovenian
Secondary keywords:	reodiktični polimeri;nelinearno vedenje;časovno odvisne mehanske lastnosti;proces lezenja;Schaperijev nelinearni model;
Type (COBISS):	Article
Pages:	str. 1-11
Issue:	ǂVol. ǂ137 , [article no.] 108535
Chronology:	Aug. 2024
DOI:	10.1016/j.polymertesting.2024.108535
ID:	24631442