| 摘要 |
<p>Tetrapolyimide films derived from oxydiphthalic dianhydride, pyromellitic acid dianhydride, p-phenylene diamine and 4,4'-diaminodiphenyl ether, and their preparation are described. The tetrapolymer films have low water absorption, low coefficients of thermal and hygroscopic expansion, high modulus and are caustic etchable and can be used in flexible printed circuit and tape automated bonding applications.</p> |
