Synthetic resins or natural rubbers -- part of the class 520 ser – Synthetic resins – From carboxylic acid or derivative thereof
Patent
1992-12-22
1994-03-08
Kight, III, John
Synthetic resins or natural rubbers -- part of the class 520 ser
Synthetic resins
From carboxylic acid or derivative thereof
525415, 528357, C08G 6384, C08G 6391
Patent
active
052928594
ABSTRACT:
A process for polymerizing lactide and up to 20 mole percent of another lactone is disclosed. The cayalysts used have the formula MZ.sub.3 wherein M is scandium, yttrium, bismuth, a lanthanide series rare earth metal or a mixture thereof and the Zs are independently the same or different highly coordinating ligands. The preferred metals M are lanthanum, cerium, praseodymium and neodymium with lanthanum being especially preferred. The preferred ligands are betadiketones, betaketoesters and malonate anions with the betadiketones such as 2,2,6,6-tetramethyl-3,5-heptanedionates being especially preferred.
REFERENCES:
patent: 3169945 (1965-02-01), Hostettler et al.
patent: 4289873 (1981-09-01), Kubo et al.
patent: 4357462 (1082-11-01), Kubo et al.
patent: 4853459 (1989-08-01), Stewart
patent: 5028667 (1991-07-01), McLain et al.
A. J. Nijenhuis et al., Polymer Bull. (1991), 25, pp. 71-77.
M. Bero et al., Makromol. Chem. 191, 2287-2296 (1990).
Shen, Z.; Sun, J. and Wu, L., Huaxue Xuebao, 48(7), pp. 686-689 (1990).
Ford Thomas M.
McLain Stephan J.
Dodson Shelley A.
E. I. Du Pont de Nemours and Company
Kight III John
LandOfFree
Rare earth metal coordination compounds as lactone polymerizatio does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Rare earth metal coordination compounds as lactone polymerizatio, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Rare earth metal coordination compounds as lactone polymerizatio will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-154549