| 摘要 |
PURPOSE:To obtain the titled high polymerization degree polyester pellets of good moldability with the pigment highly homogeneously dispersed capable of giving high-quality molded product, by solid phase polymerization of a specific master batch made up of polyester and pigment followed by secondary blending with polyester. CONSTITUTION:First, polyethylene terephthalate or a polyester consisting mainly of polyethylene terephthalate is blended with a pigment (e.g., carbon black, titanium dioxide) in a molten state to prepare a master batch with a pigment concentration <=60wt%. This master batch is brought to solid phase polymeriza tion to effect Vm in the intrinsic viscosity followed by melt blending with such a dried polyester as to be Vo in its intrinsic viscosity satisfying the equation; Vo-Vm=-0.1-0.3 so as to represent specified pigment concentration, thus obtaining the objective high-polymerization degree pellets with the pigment highly homogeneously dispersed.
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