Aging of a Polymer Core Composite Conductor Under Combined Ozone and Temperature Conditions

<p>The next generation High Temperature Low Sag Polymer Core Composite Conductors (HTLS PCCC) can experience harsh in-service environments including high temperature and highly concentrated ozone. In some extreme cases, it is possible that the conductors will experience temperatures of up to 180°C and ozone concentrations as high as 1% (10,000 ppm). Therefore, the primary goal of this research was to determine the most damaging aging conditions which could negatively affect the in-service life of the conductors. This included characterizing the aging in ozone and at high temperature of the HTLS PCCC hybrid composite rods and neat resin. It was found that exposure to 1% ozone for up to three months at room temperature did not negatively affect the flexural performance of either the neat resin epoxy, or the hybrid composite rods. When aged up to a year at 140°C no detrimental effect on flexural performance of the composite was observed, as opposed to aging at 180°C, which had a very negative effect on the properties. The aging of the epoxy at 140°C was driven almost entirely by temperature and the effect of 1% ozone, even at that temperature, was insignificant for aging times up to ninety days. A finite element model was developed and showed the residual stresses developed after aging at 140°C for a year were minimal, but for temperatures higher than 160°C were substantial. From this it was determined that the aging was thermally driven, and atmospheric high temperatures were the most damaging conditions for the PCCC conductors.</p>

Name thesis:degree_name

Ph.D.

Level thesis:degree_level

Dissertation

Year dc:date.available

2014

Author dc:creator

• Middleton, James M.

Contributors dc:contributor

• Maciej Kumosa, Ph.D.
• Davor Balzar, Ph.D.
• Yun Bo Yi
• Peter Laz
• Iwona Jasiuk

• Aging
• Composites
• Mechanical testing
• Ozone
• Polymers
• Thermal analysis
• Materials Science and Engineering
• Polymer and Organic Materials
• Polymer Science

Statement dc:rights

• <p>Copyright is held by the author. User is responsible for all copyright compliance.</p>

Language dc:language

en

Repository record dc:identifier

https://digitalcommons.du.edu/etd/427

OAI identifier oai:identifier

oai:digitalcommons.du.edu:etd-1426