Solvent induced phase separation in a nylon 6-b-polyimide-b-nylon 6 triblock copolymer

• Published in: Journal of polymer research 1997-01, Vol.4 (1), p.1-7
• Main Authors: Fu, Qiang, Livengood, Bryan P., Shen, Ching-Chang, Lin, Fu-Le, Li, Weihan, Harris, Frank W., Cheng, Stephen Z. D., Hsiao, Benjamin S.
• Format: Article
• Language: English
• Subjects: Copolymers
• ISSN: 1022-9760; 1572-8935
• DOI: 10.1007/s10965-006-0001-7

A series of new nylon 6-b-polyimide-b-nylon 6 (triblock) copolymers have been synthesized via condensation polymerization of the polyimide component and anionic polymerization of the nylon 6 component. The polyimide component is prepared from bisphenol-A dianhydride (BisA-DA) and bisaniline-P diamine (BisP) with end-capped functional groups. After the polyimides are dissolved in caprolactam, the nylon 6 anionic polymerization is initiated by the functional groups of the polyimides. The triblock copolymers can be dissolved in both m-cresol and 1,6-hexanediol. Of the two components present in the copolymers, nylon 6 crystallizes partially and BisA-DA/BisP is amorphous. Based on differential scanning calorimetry, dynamic mechanical analysis, wide angle X-ray diffraction, small angle X-ray scattering and transmission electron microscopy experiments, the copolymer films prepared from the 1,6-hexanediol solution are phase separated. The BisA-DA/Bis P and the nylon 6 components show little miscibility in the inter-lamellar amorphous region. However, in the films prepared from the m-cresol solution both components are largely miscible in the inter-lamellar amorphous region. This is due to the different solvation power of the two solvents with respect to the polyimide and nylon 6.[PUBLICATION ABSTRACT]