Structure/Property/Processing Relationships in Poss-Modified High Temperature Thermoplastic Composites

<p>Cost effective and lightweight fiber-reinforced polymers provide promising alternatives to metal alloys in both the aerospace and automotive industry and have been used in such areas since the 1980s. The majority of these polymer composites are fabricated using thermosetting epoxides due to the high service temperatures and weathering resistance associated with these systems. In recent years, however, interest has shifted to the use of high performance thermoplastics, such as PEEK, in composite manufacturing due to the potential for improved damage tolerance, production speed, and recyclability. Unfortunately, the use of these materials has been limited in large-scale production due to the extreme temperatures required to process these high performance or engineering thermoplastics. Previous research has shown that nano-structured processing aids such as polyhedral oligomeric silsesquioxane (POSS) can significantly improve the processability of said thermoplastics at low percent loadings. However, as with any additive, maintaining molecular dispersion of the additives throughout the polymer matrix is crucial to achieving the desired results. The goal of this research was to determine viable methods for incorporating POSS molecules into high performance polymer systems that could be used on an industrial scale for a variety of polymer systems. To accomplish this task, a series of inert POSS nanostructured materials were melt-compounded with commercial high performance thermoplastics to evaluate how the organically-modified corona of the POSS molecule affects its compatibility and dispersion within the polymer matrix. In addition, POSS compounds functionalized with reactive groups were also grafted to the ends of polymer chains under non-catalyzed conditions. The results of this research demonstrate the need for an improved understanding of structure-property relationships in POSS- iii modified thermoplastic resins and offer a potentially novel method of incorporating POSS molecules into high performance thermoplastic systems.</p>

Name thesis:degree_name

Master of Science (MS)

Level thesis:degree_level

Masters Thesis

Year dc:date.available

2019

Author dc:creator

• Woellner, Mitchell

Contributors dc:contributor

• Sarah E. Morgan
• Sergei I. Nazarenko
• Jeffrey S. Wiggins

• polyethersulfone
• nanocomposites
• processing
• Polymer Chemistry

Repository record dc:identifier

https://aquila.usm.edu/masters_theses/646

OAI identifier oai:identifier

oai:aquila.usm.edu:masters_theses-1697