Patent ID: 11926701
Assignee: COVESTRO DEUTSCHLAND AG
Field: Macromolecular chemistry, polymers (Chemistry)
Classification: CPC C | IPC C

Claim 5:
6. A process for preparing a polycarbonate polyol as claimed in claim 1, wherein a two-stage process is employed, wherein in a first stage, in the presence of a catalyst, an intermediate is prepared from
A) at least one α, ω-alkanediol having 4 to 8 carbon atoms,
C) diethylene glycol, and
D) at least one carbonyl component from the group consisting of diaryl carbonates, dialkyl carbonates, alkylene carbonates and COCl2, and mixtures thereof, and in a second stage this intermediate is reacted with
B) at least one polytetrahydrofuran.