HIGH RECYCLE CONTENT POLYOLS FROM THERMOPLASTIC POLYESTERS AND LIGNIN OR TANNIN

摘要

Polyester polyols, processes for making them, and applications for the polyols are disclosed. In some aspects, the polyols comprise recurring units from a thermoplastic polyester or an aromatic polyacid source, a glycol, and a lignin, tannin, or mixture thereof. Optionally, the polyols incorporate recurring units of a hydrophobe. The polyols are made in one or multiple steps; in some aspects, the thermoplastic polyester or aromatic polyacid source and the glycol are reacted first, followed by reaction with the lignin, tannin, or mixture thereof. High-recycle-content polyols having desirable properties and attributes for formulating polyurethane products, including two-component polyurethane coatings, can be made. The polyols provide a sustainable alternative to bio- or petrochemical-based polyols.

主权项

1. A polyester polyol comprising recurring units from:
(a) a digested thermoplastic polyester; (b) a glycol; and (c) a lignin, a tannin, or a mixture thereof; wherein the molar ratio of glycol to thermoplastic polyester recurring units is at least 0.8, the amount of lignin, tannin, or mixture thereof incorporated into the polyol is within the range of 0.1 to 35 wt. %, and the polyol has a hydroxyl number within the range of 25 to 800 mg KOH/g.