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In situ syntheses and phase behavior investigations of inorganic materials in organic polymer solid matrices

Posted on:1993-09-27Degree:Ph.DType:Dissertation
University:The Pennsylvania State UniversityCandidate:Lin, JunFull Text:PDF
GTID:1471390014996575Subject:Chemistry
Abstract/Summary:
This research focuses on in situ syntheses and phase behavior investigations of inorganic materials in organic polymer matrices. The central purpose of the research is to generate inorganic particles with controlled size, morphology, crystallinity and crystallographic orientation in synthetic polymer matrices.; TiS{dollar}sb2{dollar} generated in situ in polyvinylchloride was found to be nano-phase materials: 3-10 nm sized particles were evenly distributed in the polymer matrix. Inorganic/organic nano-composites were thus obtained. Physical properties of such composites, solution and electrical, were found to be different from the constituent components. However, no sign of particle crystallinity and crystallographic orientation was observed in this system.; Control of inorganic particle size, morphology, crystallinity or crystallographic orientation was achieved in the CdS-polyethyleneoxide (PEO) system. The size of the CdS particles was controlled by controlling the concentration of the inorganic reagent, CdCl{dollar}sb2{dollar}, in the PEO matrix, and the reaction temperature as well. The morphology of the particles was found to be dependent on the organization of the reaction environment. For example, irregular inorganic particles were formed in the polymer matrix at a temperature which could disrupt the organization of PEO matrix. However, cubic or fiberous particles were generated in the presence of added chemical ligands such as sodium di(2-ethylhexyl)sulfosuccinate (AOT) or 2,2{dollar}spprime{dollar},2{dollar}sp{lcub}primeprime{rcub}{dollar}-triaminotriethylamine (Tren) in this system, which presumably created a different, or organized environment for the inorganic crystallization. When crystallization was carried out in the PEO thin film system, inorganic crystals with a regular size, morphology (cubic) and crystallographic orientation (along (001) direction, or perpendicular to the polymer film surface) were generated in the presence of AOT.; Various microscopic factors such as polymer film thickness, polymer solvation capability to the inorganic starting reagent, and polymer binding capability and binding environment in influencing the inorganic crystallization were also investigated. It was found that the inorganic product formed in the polymer thin film matrix was much more regular than the formation in the polymer bulk films. However, crystallization of inorganic product was not influenced by the chemical environments when the inorganic starting reagents were not solvated in the polymer matrix.
Keywords/Search Tags:Inorganic, Polymer, Materials, Situ, Crystallographic orientation, PEO
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