| 摘要 |
PURPOSE:To obtain a relatively high elongation at break, practically usable mechanical and thermal properties, and excellent oxygen barrier properties by forming a wholly arom. polyester comprising three specific repeating units into a film. CONSTITUTION:A wholly arom. polyester comprising 40-75mol% repeating units of formula I, 12.5-30mol% repeating units of formula II, and 12.5-30mol% repeating units of formula III, the amts. of the units of formula II and formula III being substantially equimolar, is formed into a film. In the formulas, a part of hydrogen atoms bound to arom rings may be substd. Pref. the polyester has a logarithmic viscosity (0.1w/v% soln. in pentafluorophenol, at 60 deg.C) of 0.5dl/g or higher. |
