PURPOSE: To obtain an ultrahigh mol.wt. polyester with no variation in the size and shape of particles used without requiring variation by post-condensing a suspension of a low mol.wt. fine solid polyester in a liq. heat medium which does not penetrate into the polyester.
CONSTITUTION: A suspension of a low mol.wt. fine solid polyester is post- condensed at elevated temp. in a liq. heat medium which does not penetrate into the polyester. In the procedure, the polycondensation of the polyester proceeds, and in accordance with the rise of the melting temp., the polycondensation temp. also rises gradually in the same degree. The most advantageous polycondensation temp. can easily be judged by a preliminary experiment. The m.p. of the polyester particles at the time is also easily measured by collecting a sample from the batch during reaction.
RIGIA DOMINGESU
PEETAA KURAIN
