Experimental tests of polymer reptation : a thesis presented in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Physics at Massey University

Simple item page
dc.contributor.authorKomlosh, Michal
dc.contributor.authorKomlosh, Michal
dc.date.accessioned2011-05-17T23:14:40Z
dc.date.available2011-05-17T23:14:40Z
dc.date.issued1999
dc.description.abstractPulsed Gradient Spin Echo Nuclear Magnetic Resonance (PGSE-NMR) and rheology measurements were used to test whether the dynamics of entangled polymer chains in semidilute solution follow the reptation theory. Nine molar masses from 1 to 20 million daltons at a fixed concentration of 4.96% w/v along with a range of concentrations from 4.96% to 23.58% w/v at fixed molar mass of 3 million daltons were studied using PGSE-NMR techniques. The response to mechanical deformation of five different concentrations from 4.96% to 23.58% w/v at fixed molar mass of 3.9 million daltons was also studied. The distance and time scales accessed by PGSE-NMR were 20 to 1000 nm and 10 to 3000 ms respectively. As a result the mean square segmental motion over three reptation regimes was obtained and the reptation finger print, 〈(r(t) - r(0))〉 ~ t1/4, was observed. The resulting concentration and molecular weight scaling laws for the tube disengagement time, center of mass diffusion and the tube diameter, which were obtained in PGSE-NMR and rheology experiments, were found to be in good agreement with the reptation theory and its standard modifications, and a good quantitative fit to the mean square displacement was given by this theory. Local anisotropic motion of polymer chains at the level of the Rouse time was observed using double-PGSE NMR methods. These suggested a possible cooperative motion of polymer chains in entangled environment which challenges the basic assumptions of the reptation theory. Evidence of intra-chain spin diffusion was found. As a consequence relevant corrections incorporating the phenomenon into the PGSE-NMR data had to be made.en_US
dc.identifier.urihttp://hdl.handle.net/10179/2352
dc.identifier.wikidataQ112849634
dc.identifier.wikidata-urihttps://www.wikidata.org/wiki/Q112849634
dc.publisherMassey Universityen_US
dc.rightsThe Authoren_US
dc.subjectPolymersen_US
dc.subjectPolymer chainsen_US
dc.titleExperimental tests of polymer reptation : a thesis presented in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Physics at Massey Universityen_US
dc.typeThesisen_US
thesis.degree.disciplinePhysics
thesis.degree.grantorMassey University
thesis.degree.levelDoctoral
thesis.degree.levelDoctoralen
thesis.degree.nameDoctor of Philosophy (Ph.D.)
Files
Original bundle
Now showing 1 - 2 of 2
Thumbnail Image
Name:
02_whole.pdf
Size:
4.36 MB
Format:
Adobe Portable Document Format
Description:
Download
Thumbnail Image
Name:
01_front.pdf
Size:
439.06 KB
Format:
Adobe Portable Document Format
Description:
Download
License bundle
Now showing 1 - 1 of 1
Thumbnail Image
Name:
license.txt
Size:
804 B
Format:
Item-specific license agreed upon to submission
Description:
Download
Collections
Theses and Dissertations