Polyester composition, process and apparatus for preparation thereof

摘要

A polyester composition containing fine particles with an average size of 0.03-1.8 mu m which have been surface-modified with polyester (B) of which less than 70 mole percent of the repeating units consist of ethylene terephthalate, butylene terephthalate or ethylene naphthalate units, in polyester (A) of which at least 70 mole percent of the repeating units consist of ethylene terephthalate, butylene terephthalate or ethylene naphthalate units. The composition has a filtration pressure increase rate of no greater than 10 kg/cm<2>/hr when filtered using a double layer of 2400 mesh wire filters with an inner diameter of 64 mm phi , a temperature of 290 DEG C and a filtration rate of 33.3 g/min.