The dilute solution properties of two polyimides have been studied using size exclusion chromatography, light scattering and viscometry in various solvents. Molecular parameters (conformation and aggregation) are found to be solvent dependent. Addition of a non-solvent to 6FDA-mPDA, a Γuorine-(H 2 O
Effects of Catalyst Isoquinoline in Polymerization Process on the Aggregation Structures of Polyimide in Solution
β Scribed by Xiangyang Liu; Jin Yang; Linghong Guo; Yi Gu
- Publisher
- John Wiley and Sons
- Year
- 2005
- Tongue
- English
- Weight
- 165 KB
- Volume
- 26
- Category
- Article
- ISSN
- 1022-1336
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β¦ Synopsis
Abstract
Summary: A thermoreversible gel or a dendritic crystal has been obtained in a novel polyimide solution at low temperature, depending on the approach taken to add the isoquinoline catalyst during the polymerization process. By adding the isoquinoline at the beginning of polymerization, two kinds of layer structures in the gel are developed. However, by adding the isoquinoline after the polymerization has been carried out for one hour, a perfect dendritic crystalline structure is gradually developed in the polymerization solution.
PLM photographs of the obtained polyimide crystals.
magnified imagePLM photographs of the obtained polyimide crystals.
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