| 摘要 |
<p>The polyesters (I) are products of terephthalic acid (III)/glycol ester polymerisation containing at least 80% of (III). The atomic proportion of Sb to Ge is 0.1-2.0. Ge compounds give good whiteness and transparency. Sb metal gives freedom from ether links. The combination of these catalysts gives highly polymerised polyesters useful for fibres and films of high whiteness, transparency and good heat resistance combining the advantages of each catalyst. Germanium oxide (II) issued as a solution in ethylene glycol. Concentration of (II) is 0.005-0.5 wt.% of (I). The Sb metal particles are sized 1-100 microns. Polymerisation is performed at 220-320 degrees C and 0.1 10 mmHg pressure.</p> |
