LIPASE-CATALYZED SYNTHESIS OF AROMATIC POLYESTERS

The enzymatic synthesis of aromatic polyesters by direct polyesterific ation between a diacid and a diol is described. The effects of the typ e of substrate, type and quantities of lipase, temperature, vacuum, an d reaction time on the synthesis of aromatic polyesters were studied i n detail. Among three lipases investigated, only Novozym 435 worked we ll for aromatic polyester synthesis. Temperature and vacuum played an important role in obtaining a high molar mass of the aromatic polyeste rs. Furthermore, with isophthalic acid and 1,6-hexanediol as substrate s, the mass average molar mass of the polyester obtained increased wit h an increase in the lipase quantity up to 0.375 g (11.7%, w/w of tota l reactor contents). The mass average molar mass of the polyester was as high as 50 000 g mol(-1) in 168 h, with a polydispersity of PD appr oximate to 1.4.