abstract |
An aromatic polyester consisting essentially of (1) p-oxybenzoyl units or the 3-methyl- or 3-chloro-derivatives thereof; (2) 3,4'-dioxydiphenylether or 3,4'-dioxybenzophenone units or the 3'-methyl- or 3'-chloro- derivatives thereof or terephthaloyldi (3-methyl-4-oxybenzene) units; and (3) terephthaloyl units and filaments thereof. |