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Extreme Wear Resistance in Carbon Nanotube and Other Nanocarbon Filled Polytetrafluoroethylene.

Record Type:	Language materials, manuscript : Monograph/item
Title/Author:	Extreme Wear Resistance in Carbon Nanotube and Other Nanocarbon Filled Polytetrafluoroethylene./
Author:	Makowiec, Mary Elizabeth.
Description:	1 online resource (148 pages)
Notes:	Source: Dissertation Abstracts International, Volume: 79-12(E), Section: B.
Contained By:	Dissertation Abstracts International79-12B(E).
Subject:	Mechanical engineering. -
Online resource:	click for full text (PQDT)
ISBN:	9780438206564

Extreme Wear Resistance in Carbon Nanotube and Other Nanocarbon Filled Polytetrafluoroethylene.
Makowiec, Mary Elizabeth.

Extreme Wear Resistance in Carbon Nanotube and Other Nanocarbon Filled Polytetrafluoroethylene. - 1 online resource (148 pages)

Source: Dissertation Abstracts International, Volume: 79-12(E), Section: B.

Thesis (Ph.D.)--Rensselaer Polytechnic Institute, 2018.

Includes bibliographical references

This dissertation is focused on identifying and analyzing effective nanoscale fillers that reduce the wear rate of sintered polytetrafluoroethylene (PTFE) composites above and beyond the wear rate reduction typically seen from microscale fillers, which typically reduce the wear rate of PTFE by up to 2 orders of magnitude. This work identifies two such nanoscale fillers, carboxyl-functionalized carbon nanotubes and mesoporous nanocarbon, both of which show great promise as PTFE fillers, reducing the wear rate by over three orders of magnitude. This dissertation goes on to explore potential mechanisms by which the fillers reduce the wear rate. In particular, several interesting findings were made. In a similar, but melt-processible fluoropolymer, FEP, which may have better distributed filler through the composite, nanoscale carbon-filled composites had poorer low wear rate performance than when these carbon nanofillers were in PTFE composites, while previously identified nanoscale alpha-phase alumina filled composites had similar wear rates in both polymers, suggesting that there may be different methods of wear reduction caused by these two groups of effective nanoscale fillers. FTIR-ATR analysis demonstrated higher levels of carboxyl ions on the worn surfaces of PTFE composites, which may indicate that PTFE chain scission and metal chelation could be occurring, which can improve the quality not only of the nanocomposite wear surfaces, but also of their transfer films formed atop the mating countersurfaces. In addition, XRD scans indicated that there may be a shift in the crystalline phases that are present at the ambient test temperature employed in wear testing here, which may improve PTFE's innate resistance to wear and may also result in the production of smaller wear debris.

Electronic reproduction.
Ann Arbor, Mich. :
ProQuest,
2018

Mode of access: World Wide Web

ISBN: 9780438206564Subjects--Topical Terms:

557493
Mechanical engineering.
Index Terms--Genre/Form:

554714
Electronic books.

Extreme Wear Resistance in Carbon Nanotube and Other Nanocarbon Filled Polytetrafluoroethylene.
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500 $a Source: Dissertation Abstracts International, Volume: 79-12(E), Section: B.
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502 $a Thesis (Ph.D.)--Rensselaer Polytechnic Institute, 2018.
504 $a Includes bibliographical references
520 $a This dissertation is focused on identifying and analyzing effective nanoscale fillers that reduce the wear rate of sintered polytetrafluoroethylene (PTFE) composites above and beyond the wear rate reduction typically seen from microscale fillers, which typically reduce the wear rate of PTFE by up to 2 orders of magnitude. This work identifies two such nanoscale fillers, carboxyl-functionalized carbon nanotubes and mesoporous nanocarbon, both of which show great promise as PTFE fillers, reducing the wear rate by over three orders of magnitude. This dissertation goes on to explore potential mechanisms by which the fillers reduce the wear rate. In particular, several interesting findings were made. In a similar, but melt-processible fluoropolymer, FEP, which may have better distributed filler through the composite, nanoscale carbon-filled composites had poorer low wear rate performance than when these carbon nanofillers were in PTFE composites, while previously identified nanoscale alpha-phase alumina filled composites had similar wear rates in both polymers, suggesting that there may be different methods of wear reduction caused by these two groups of effective nanoscale fillers. FTIR-ATR analysis demonstrated higher levels of carboxyl ions on the worn surfaces of PTFE composites, which may indicate that PTFE chain scission and metal chelation could be occurring, which can improve the quality not only of the nanocomposite wear surfaces, but also of their transfer films formed atop the mating countersurfaces. In addition, XRD scans indicated that there may be a shift in the crystalline phases that are present at the ambient test temperature employed in wear testing here, which may improve PTFE's innate resistance to wear and may also result in the production of smaller wear debris.
520 $a The findings identified and discussed in this dissertation suggest that there are likely several different mechanisms of wear rate reduction in nanoscale composites, and may suggest that unlike what is currently believed about microscale fillers, nanoscale fillers act to reduce wear in different ways. The research completed in this dissertation provides several novel effective filler materials in PTFE and adds insight into the mechanism of wear reduction for carbon-based nanofillers.
533 $a Electronic reproduction. $b Ann Arbor, Mich. : $c ProQuest, $d 2018
538 $a Mode of access: World Wide Web
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710 2 $a Rensselaer Polytechnic Institute. $b Mechanical Engineering. $3 1178915
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