Materials Science and Engineering Commons^™

Structure And Properties Of Nanoclay Reinforced Polymer Films, Fibers And Nonwovens, Raghavendra Ratnakar Hegde

Doctoral Dissertations

In this research, influence of different levels of Closite Na⁺ additives on the microstructure, morphology and mechanical properties of polymer products was studied. Importance was given to understand the additive level, extent of dispersion in matrix, change in microstructure and respective property observed in the end product. Polypropylene spunbond and meltblown web samples with various levels of Closite Na⁺ additives were produced and characterized. Injection molded polypropylene nanocomposite with 1 to 15 wt% nanoclay additives were also prepared and characterized for microstructure and mechanical properties.

Crystallization kinetics studies showed significant increase in crystallization rates on nylon 6 even …

Morphological Characterization Of Irradiated Ultra High Molecular Weight Polyethylene (Uhmwpe), Christopher Phillip Stephens

Doctoral Dissertations

Effects of radiation (gamma and proton) on Ultra High Molecular Weight Polyethylene (UHMWPE) is studied for prosthetic joints and for radiation shielding for manned space missions. The first section of the dissertation will cover gamma radiation effects on UHMWPE by means of solubility, hardness, three-phase model, crystallite thickness, and molecular mobility studies. The second part will cover proton radiation effects on UHMWPE by means of solubility, three-phase crystallite model, and crystallite thickness study. The combined studies of the gamma irradiated samples shows that chain scission occurs on the surface and crosslinking in the center. The combined studies of the proton …