Date of Award
Spring 2019
Degree Type
Masters Thesis
Degree Name
Master of Science (MS)
School
Polymer Science and Engineering
Committee Chair
Sarah E. Morgan
Committee Chair School
Polymer Science and Engineering
Committee Member 2
Sergei I. Nazarenko
Committee Member 2 School
Polymer Science and Engineering
Committee Member 3
Jeffrey S. Wiggins
Committee Member 3 School
Polymer Science and Engineering
Abstract
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.
Copyright
2019, Mitchell Woellner
Recommended Citation
Woellner, Mitchell, "Structure/Property/Processing Relationships in Poss-Modified High Temperature Thermoplastic Composites" (2019). Master's Theses. 646.
https://aquila.usm.edu/masters_theses/646