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SGER: Supercritical Levitation Polymerization and Processing

SGER：超临界悬浮聚合和加工

基本信息

批准号：
9310232
负责人：
Erdogan Kiran
金额：
$ 5万
依托单位：
University of Maine
依托单位国家：
美国
项目类别：
Standard Grant
财政年份：
1993
资助国家：
美国
起止时间：
1993-05-15 至 1995-10-31
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=9310232&HistoricalAwards=false
关键词：
SGER Supercritical Levitation Polymerization Processing

项目摘要

In supercritical polymerization processes, polymer chains grow to molecular weights determined by their solubility under the prevailing density (or pressure and temperature) conditions of the solvent. Further growth in the chain length results in phase separation and leads to precipitation. In this project, polymerizations will be conducted under isopycnic conditions by adjusting the density of the solvent environment to be identical to the density of the polymer formed. This iso- density operation is expected to insure levitation by buoyancy and prevent precipitation of the phase-separated polymer. Density adjustments are readily achievable for supercritical solvents through manipulation of either the pressure of the temperature, of the solvent composition (if mixtures are used), and isopycnic conditions for a variety of polymers and polymerization systems are possible. This is a way to simulate the micro gravity environment of space-based processes on earth. The objective of the research project is to make polymeric materials of precise geometries and morphologies by synthesizing them in a supercritical fluid of precisely the same density as the product polymer. This would prevent precipitation of the polymer and permit polymerization of molecules of any desired structure to be fabricated. The research will focus on testing his hypothesis by synthesizing polystyrene and crystallizing polyethylene in isopycnic supercritical fluid solvents. He will explore using mixtures of fluids such as carbon dioxide or butane with fluids of higher density such as xenon or sulfur hexafloride.

在超临界聚合过程中，分子量由它们在水溶液中的溶解度决定。主要的密度（或压力和温度）条件溶剂后链长的进一步增长导致相分离并导致沉淀。在这个项目中，聚合将在等密度条件下进行通过将溶剂环境的密度调节为与所形成的聚合物的密度相同。这个iso- 高密度运行预计将确保浮力悬浮并防止相分离的聚合物沉淀。对于超临界流体，密度调节是容易实现的。溶剂通过操纵的压力，温度，溶剂组合物（如果混合物使用），以及各种聚合物的等密度条件，聚合系统是可能的。我们这种技术可以模拟天基微重力环境地球上的过程。该研究项目的目标是使聚合物精确几何形状和形态的材料，在超临界流体中合成它们，与产品聚合物的密度相同。这将防止聚合物的沉淀并允许聚合任何所需结构的分子。的研究将集中在测试他的假设，等密度聚苯乙烯和结晶聚乙烯超临界流体溶剂他将探索使用混合物例如二氧化碳或丁烷的流体，更高密度，如氙或硫六氟化硫。