Matches in SemOpenAlex for { <https://semopenalex.org/work/W2554427883> ?p ?o ?g. }
- W2554427883 endingPage "47" @default.
- W2554427883 startingPage "35" @default.
- W2554427883 abstract "We present unique nonlinear rheological data of well-defined symmetric Cayley-tree poly(methyl methacrylates) in shear and uniaxial extension. Earlier work has shown that their linear viscoelasticity is governed by the hierarchical relaxation of different generations, whereas the segments between branch points are responsible for their substantial strain hardening as compared to linear homopolymers of the same total molar mass at the same value of imposed stretch rate. Here, we extend that work in order to obtain further experimental evidence that will help understanding the molecular origin of the remarkable properties of these highly branched macromolecules. In particular, we address three questions pertinent to the specific molecular structure: (i) Is steady state attainable during uniaxial extension? (ii) What is the respective transient response in simple shear? and (iii) How does stress relax upon cessation of extension or shear? To accomplish our goal, we utilize state-of-the-art instrumentation, i.e., filament stretching rheometry and cone-partitioned plate shear rheometry for polymers with 3 and 4 generations, and complement it with state-of-the-art modeling predictions using the branch-on-branch (BoB) algorithm. The data indicate that the extensional viscosity reaches a steady state value, whose dependence on extensional rate is identical to that of entangled linear and other branched polymer melts. Nonlinear shear is characterized by transient stress overshoots and the validity of the Cox–Merz rule. Remarkably, nonlinear stress relaxation is much broader and slower in extension compared to shear. It is also slower at higher generation, and rate-independent for rates below the Rouse rate of the outer segment. For extension, the relaxation time is longer than that of the linear stress relaxation, suggesting a strong “elastic memory” of the material. These results are described by BoB semiquantitatively, both in linear and nonlinear shear and extensional regimes. Given the fact that the segments between branch points are less than three entanglements long, this is a very promising outcome that gives confidence in using BoB for understanding the key features. Moreover, the response of the segments between generations controls the rheology of the Cayley trees. Their substantial stretching in uniaxial extension appears responsible for strain hardening, whereas coupling of stretches of different parts of the polymer appears to be the origin of the slower subsequent relaxation of extensional stress. Concerning the latter effect, for which predictions are not available, it is hoped that the present experimental findings and proposed framework of analysis will motivate further developments in the direction of molecular constitutive models for branched and hyperbranched polymers." @default.
- W2554427883 created "2016-11-30" @default.
- W2554427883 creator A5009328471 @default.
- W2554427883 creator A5047584198 @default.
- W2554427883 creator A5060487809 @default.
- W2554427883 creator A5068749262 @default.
- W2554427883 date "2017-01-01" @default.
- W2554427883 modified "2023-10-12" @default.
- W2554427883 title "Stress growth and relaxation of dendritically branched macromolecules in shear and uniaxial extension" @default.
- W2554427883 cites W1095546527 @default.
- W2554427883 cites W1626105030 @default.
- W2554427883 cites W1672001074 @default.
- W2554427883 cites W1964023442 @default.
- W2554427883 cites W1964930444 @default.
- W2554427883 cites W1967909450 @default.
- W2554427883 cites W1968678546 @default.
- W2554427883 cites W1972341385 @default.
- W2554427883 cites W1972596611 @default.
- W2554427883 cites W1974557413 @default.
- W2554427883 cites W1976443916 @default.
- W2554427883 cites W1981583521 @default.
- W2554427883 cites W1986069638 @default.
- W2554427883 cites W2001268360 @default.
- W2554427883 cites W2005098746 @default.
- W2554427883 cites W2006993954 @default.
- W2554427883 cites W2007417000 @default.
- W2554427883 cites W2011918691 @default.
- W2554427883 cites W2015257860 @default.
- W2554427883 cites W2019251576 @default.
- W2554427883 cites W2021288382 @default.
- W2554427883 cites W2022032684 @default.
- W2554427883 cites W2024207509 @default.
- W2554427883 cites W2033136487 @default.
- W2554427883 cites W2033302412 @default.
- W2554427883 cites W2035972780 @default.
- W2554427883 cites W2037227840 @default.
- W2554427883 cites W2043219772 @default.
- W2554427883 cites W2044370378 @default.
- W2554427883 cites W2045348594 @default.
- W2554427883 cites W2047841306 @default.
- W2554427883 cites W2048178958 @default.
- W2554427883 cites W2049452413 @default.
- W2554427883 cites W2056608431 @default.
- W2554427883 cites W2058809871 @default.
- W2554427883 cites W2059942247 @default.
- W2554427883 cites W2067646745 @default.
- W2554427883 cites W2069143061 @default.
- W2554427883 cites W2071347263 @default.
- W2554427883 cites W2074394590 @default.
- W2554427883 cites W2082142485 @default.
- W2554427883 cites W2084970328 @default.
- W2554427883 cites W2089262917 @default.
- W2554427883 cites W2092046719 @default.
- W2554427883 cites W2130754077 @default.
- W2554427883 cites W2159618415 @default.
- W2554427883 cites W2285346798 @default.
- W2554427883 cites W2291036364 @default.
- W2554427883 cites W2314271523 @default.
- W2554427883 cites W2320863881 @default.
- W2554427883 cites W2326503482 @default.
- W2554427883 cites W2326905084 @default.
- W2554427883 cites W2329599873 @default.
- W2554427883 cites W2333405923 @default.
- W2554427883 cites W2344651978 @default.
- W2554427883 cites W2346002641 @default.
- W2554427883 cites W2415410817 @default.
- W2554427883 cites W2473185991 @default.
- W2554427883 cites W2508351881 @default.
- W2554427883 cites W611830728 @default.
- W2554427883 doi "https://doi.org/10.1122/1.4966040" @default.
- W2554427883 hasPublicationYear "2017" @default.
- W2554427883 type Work @default.
- W2554427883 sameAs 2554427883 @default.
- W2554427883 citedByCount "13" @default.
- W2554427883 countsByYear W25544278832017 @default.
- W2554427883 countsByYear W25544278832019 @default.
- W2554427883 countsByYear W25544278832020 @default.
- W2554427883 countsByYear W25544278832021 @default.
- W2554427883 countsByYear W25544278832022 @default.
- W2554427883 countsByYear W25544278832023 @default.
- W2554427883 crossrefType "journal-article" @default.
- W2554427883 hasAuthorship W2554427883A5009328471 @default.
- W2554427883 hasAuthorship W2554427883A5047584198 @default.
- W2554427883 hasAuthorship W2554427883A5060487809 @default.
- W2554427883 hasAuthorship W2554427883A5068749262 @default.
- W2554427883 hasBestOaLocation W25544278832 @default.
- W2554427883 hasConcept C101082671 @default.
- W2554427883 hasConcept C121332964 @default.
- W2554427883 hasConcept C135628077 @default.
- W2554427883 hasConcept C135768490 @default.
- W2554427883 hasConcept C144423054 @default.
- W2554427883 hasConcept C149912024 @default.
- W2554427883 hasConcept C15744967 @default.
- W2554427883 hasConcept C158622935 @default.
- W2554427883 hasConcept C159985019 @default.
- W2554427883 hasConcept C165682214 @default.
- W2554427883 hasConcept C186541917 @default.
- W2554427883 hasConcept C191172559 @default.