Patent ID: 6166169
Filing Date: 2000-12-26
Classification: C08G,C08K

Abstract:
An aliphatic polyester and/or copolyester, obtained from a polyreaction of at least one monomer selected from lactides, lactones, cyclic carbonates or cyclic anhydrides wherein a reactive mixture is used in the polyreaction, the reactive mixture comprises at least one catalyst of the formula(M) (X.sub.1, X.sub.2. . . X.sub.m).sub.n (I)wherein M is a metal selected from group 3-12 of the periodic system and from the elements Al, Ga, In, Tl, Sn, Pb, Sb and Bi; (X.sub.1, X.sub.2 . . . Xm) is a substituent selected from one of the compound classes of alkyls, aryls, oxides, carboxylates, halogenides, and alkoxides and compounds containing elements from group 15 and/or 16 of the periodic system; m is a whole number ranging from 1 to 6, and n is a whole number ranging from 0 to 6 andat least one co-catalyst of the formula(Y) (R.sub.1, R.sub.2 . . . R.sub.q).sub.p (II)where Y is an element selected from group 15 or 16 of the periodic system; (R.sub.1, R.sub.2 . . . R.sub.q) is a substituent selected from one of the compound classes of alkyls, aryls, oxides, halogenides, oxyalkyls, aminoalkyls, thioalkyls, phenoxides, aminoaryls, and thioaryls; q is a whole number ranging from 1 to 6, and p is a whole number ranging from 0 to 6, wherein the number average molecular weight of the polyester and/or copolyester is between 30,000 and 300,000 g/mol.