| 摘要 |
RD- 17907 POLYETHERIMIDES AND PRECURSORS THEREFOR Polyetherimide precursor compositions are prepared by reacting a mixture of at least two diamines selected from the group consisting of o-phenylenediamine, m-phenylenedia-mine and 4-aminophenyl ether with the esterification product of a low molecular weight alkanol such as methanol and an ether tetracarboxylic acid dianhydride, preferably 3,4-di-carboxyphenyl ether dianhydride. Said polyimide precursor compositions may be converted to polyimides useful in composite formation, by gently heating to remove excess alkanol and subsequently baking at temperatures in the range of about 275-375.degree.C. |
