標題: | Thermally and mechanically enhanced clay/polyimide nanocomposite via reactive organoclay |
作者: | Tyan, HL Liu, YC Wei, KH 材料科學與工程學系 Department of Materials Science and Engineering |
公開日期: | 1-七月-1999 |
摘要: | High modulus and thermally stable clay/polyimide (pyromellitic dianhydride-4,4'-oxydianiline, PMDA-ODA) nanocomposites were synthesized from reactive organoclay and poly(amic acid). The reactive organoclay was formed by using p-phenylenediamine as a swelling agent for silicate layers of montmorillonite. The swelling process was first carried out through ion exchange between the onium of one amine end group of p-phenylenediamine and the sodium ion in montmorillonite. The other amine end group of p-phenylenediamine reacted with the dianhydride end group of poly(amic acid), producing an irreversible swelling. This irreversible swelling resulted in a nanostructured material containing intercalated nanometer silicate layers dispersed in PMDA-ODA as confirmed by both X-ray and transmission electron microscopy. The glass transition temperature and the thermal decomposition temperatures of this type of clay/PMDA-ODA are higher than that of pure PMDA-ODA. A 2,5-fold increase in the modulus of clay/PMDA-ODA film was obtained as compared to that of pure PMDA-ODA film. Both the maximum and the elongation-for-break of these clay/PMDA-ODA nanocomposites increased with the amount of organoclay. The maximum reduction in out-of-plane coefficient of thermal expansion of this type clay/PMDA-ODA was 50% as compared to that of pure PMDA-ODA. |
URI: | http://hdl.handle.net/11536/31251 |
ISSN: | 0897-4756 |
期刊: | CHEMISTRY OF MATERIALS |
Volume: | 11 |
Issue: | 7 |
起始頁: | 1942 |
結束頁: | 1947 |
顯示於類別: | 期刊論文 |