Process for making high airflow and low compression set viscoelastic polyurethane foam

摘要

A reaction system comprising (a) a polyisocyanate component and (b) an isocyanate reactive component for preparation of a polyurethane foam having high air flow with low compression set is provided. The isocyanate reactive component comprises (i) from 45 to 70% by weight of one or more PO-rich polyols having a combined number average equivalent weight from 210 to 510, (ii) from 20 to 30% by weight of one or more ethylene oxide polyols having a combined number average equivalent weight from 200 to 500, (iii) from 10 to 25% by weight of one or more ethylene oxide-alkylene oxide polyethers having a combined number average equivalent weight from 300 to 800; and (iv) from 0.5 to 15% by weight of one or more PO-rich polyols having a functionality of 1 to 4 and a combined number average equivalent weight of 2,000 to 6,000.

主权项

1. A reaction system for preparation of a viscoelastic polyurethane foam comprising:
(a) a polyisocyanate component; (b) an isocyanate reactive component comprising:
(i) from 45 to 65% by weight of the isocyanate reactive component of one or more propylene oxide rich (PO-rich) polyols having a combined number average equivalent weight from 210 to 510, a functionality of 2.4 to 4 and a propylene oxide content of at least 70% by weight;(ii) from 20 to 30% by weight of the isocyanate reactive component of one or more ethylene oxide (EO-rich) polyols having a combined number average equivalent weight from 200 to 500, a functionality of from 2 to 4 and an ethylene oxide content of at least 70 wt % by weight;(iii) from 10 to 25% by weight of the isocyanate reactive component of one or more ethylene oxide-alkylene oxide monols having a combined number average equivalent weight from 300 to 800 and an ethylene oxide content of 40 to 60 wt %, wherein the alkylene oxide is propylene oxide, butylene oxide, or combinations thereof; and(iv) from 0.5 to 15% by weight of the isocyanate reactive component of one or more PO-rich polyols having a functionality of 1 to 4, a combined number average equivalent weight of 2,000 to 6,000 and a propylene oxide content of at least 70% by weight; (c) water; and (d) a catalyst component.