公开(公告)号：DE19629430A1

公开(公告)日：1998-01-29

申请号：DE19629430

申请日：1996-07-22

Applicant: HOECHST AG

Inventor： SIMON PETER DR ,  BLATTER KARSTEN DR ,  HERMANN-SCHOENHERR OTTO DR ,  LERCH ALEXANDER DR ,  STOCK JOCHEN DR ,  LANGER JOERG

IPC: C08G63/688 ,  C08G63/78 ,  C08G63/81 ,  C08G63/181 ,  C08G63/199 ,  C08G63/672 ,  C08L67/00 ,  D06M15/507

Abstract: Disclosed is a method of preparing polyesters in powder form by means of polycondensation of dicarboxylic acid diol precondensates (oligomers) at elevated temperature in a heat transfer medium in the presence of polycondensation catalysts and optionally cocondensable modifiers. The liquid heat transfer medium is inert and free of aromatic components and has a boiling point in the range of 180 to 300 DEG C. The dicarboxylic acid diol precondensate contains on analytical average 1 to 30 mol % oligomer or monomer containing at least one sulfonic acid group. The weight ratio of dicarboxylic acid diol precondensate to liquid heat transfer medium is in the range of 20:80 to 80:20 and the polycondensation is carried out in the presence of a dispersion stabilizer, the resulting polyester being water-soluble.