Date of Award
Fall 2002
Document Type
Dissertation - Restricted
Degree Name
Doctor of Philosophy (PhD)
Department
Chemistry
First Advisor
Wilkie, Charles A.
Second Advisor
Adair, Paul
Third Advisor
Hossenlopp, Jeanne
Abstract
For an industrialized country the United States has one of the highest fire death rates. According to the National Fire Data Center there were 14.9 deaths per million people in 1998, making it the third leading cause of death in the home. Therefore it has become necessary to take measures to prevent fires. Apart from the formation of fire brigades and fire laws, one of the most important actions has been incorporation of fire retardants into the surroundings The area of fire retardancy has shown a significant interest in clay-polymer nanocomposites. This is due to the significant decrease in flammability and increase in mechanical properties of the nanocomposites compared to the virgin polymer. It is thought that the enhancement in polymer properties is due to the layered structure of clay. Graphite is another layered material and it is thought that an improvement in polymer properties may also be observed. This research has examined the thermal and mechanical properties of various graphite-polymer nanocomposites prepared by several methods. A decrease in flammability of nanocomposites compared to virgin polymer is observed, though not always as significant as that observed for clays. A decrease rather than an increase in mechanical properties is observed. In addition we have also studied the effect of cross-linking on the thermal stability of polybutadiene with various diols, poly(methyl methacrylate) with divinylbenzene, and polystyrene with various dimethacrylates. From this work and previous work it has been shown that it is the size and type of cross-link that is important for enhanced thermal stability rather than the number of cross-links.