abstract |
The present invention relates to a process for obtaining continuously polyethylene terephthalate modified by -SiO- groups in a proportion of 300-700 ppm of Si during the direct esterification reaction between terephthalic acid and ethylene glycol, followed by polycondensation in a known manner by introducing methoxyethyl silicate or propyl silicate at a time when the prepolymer has a weight-average molecular mass of between 9,000 and 16,000, a polydispersity index of between 1.5 and 2, and when it is at a temperature of between 260 degrees and 290 degrees C. and at a pressure of between 1.5 and 2.5 bars, the silicate/prepolymer reaction time being at least 5 minutes. The present invention also relates to pilling-free fibres originating from the modified polyethylene terephthalate and to a process for obtaining them. |