Degree Type

Dissertation

Date of Award

2002

Degree Name

Doctor of Philosophy

Department

Chemical and Biological Engineering

First Advisor

Joshua U. Otaigbe

Abstract

Due to the consequence of expensive development costs that arise with manufacturing and synthesizing new polymers, interest in polymer blends has gained considerable attention in recent years. It is well known that the production of miscible and immiscible blends of polymers can lead to composite materials with special chemical, thermal, mechanical, and rheological properties. The morphology of immiscible polymer blends arises during mixing and is affected by the processing conditions, particular interactions, and the interfacial tension and viscosity ratio between the components. The significance of the interfacial energy between the blend components and its inherent effect on the rheology is of extreme importance to others and our research. Understanding the effect that the blending conditions and compositions of the phases have on the overall morphology can allow manipulation of this morphology that can lead to uniquely tailored materials.;Recent developments of low-Tg inorganic phosphate glasses (Pglass) have led to interest in inorganic-organic hybrids that can be processed via conventional thermoplastic blending and injection molding at low temperatures (below 350°C). This dissertation discusses the continued research of Otaigbe and coworkers by using a special low-Tg (~120°C), tin-based phosphate glass (Pglass) blended with thermoplastics such as polystyrene (PS), low-density polyethylene (LDPE), and polypropylene (PP). The present research demonstrates a facile method for producing unique inorganic-organic hybrids under low temperatures with tailored properties. This is made possible by the relative ease of deformation and elongation of the low-Tg Pglass phase within the polymer melt matrix. We analyzed the rheology, morphology, and ultimately the processing conditions on the Pglass-polymer hybrids. Additionally, the crystallization behavior was observed for the semicrystalline LDPE and PP matrices with varying amounts of Pglass. Experiments on the phase behavior and continuity followed by the interfacial properties of these systems were performed. Finally, the applicability of the Pglass-polymer hybrids to established polymer emulsion models was investigated in order to attempt to justify the polymeric behavior of these inorganic phosphate glass hybrids.

DOI

https://doi.org/10.31274/rtd-180813-12862

Publisher

Digital Repository @ Iowa State University, http://lib.dr.iastate.edu

Copyright Owner

Peter Christopher Guschl

Language

en

Proquest ID

AAI3073449

File Format

application/pdf

File Size

201 pages

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