| 摘要 |
A novel polyester is provided which has been found to exhibit an anisotropic melt phase at a temperature which enables it readily to undergo melt processing to form quality fibers, molded articles, etc. The polyester of the present invention includes as essential ingredients moieties derived from para-hydroxy benzoic acid, 2,6-naphthalene dicarboxylic acid, terephthalic acid, and methylhydroquinone in the proportions indicated. In a preferred embodiment the polyester is capable of undergoing melt processing at a temperature below approximately 320 DEG C., and in a particularly preferred embodiment at a temperature below approximately 300 DEG C. (e.g., with standard equipment commonly used to melt process polyethylene terephthalate). Fibers conveniently can be melt spun from the polyester of the present invention which exhibit tenacity values which are enchanced upon thermal treatment. It surprisingly has been found that the polyester of the present invention exhibits a hydrolytic stability which is substantially greater than that of the polyester of U.S. Pat. No. 4,083,829.
|
