摘要 |
<p>Polybenzoxazoles (I) are prepd. by reacting dicarboxylic acid halides with a mixt. of bis-ortho-aminophenols of formula (II) and (III). (where X and Y are O,S,SO,SO2CO,CH2 or C (Me)2) at (-20) to 100 degrees C in an organic solvent, separating the polyoxamide from the reaction mixt. and heating the aromatic polyoxamide at 200-400 degrees C. (II) and (III) are used in a mol.ratio of 1:9-9:1. Besides being resistant to temp. fluctuations. and radiation (I) has improved solubility in organic solvent (I) may be used in films, coatings, adhesives FRP, electronics, (petro)chemical machinery, aircraft, nuclear industry and space technology.</p> |