US 11,912,815 B2
Viscoelastic polyurethane foams
Qinghao Meng, Angleton, TX (US); Meagan Broadway, Freeport, TX (US); Christopher Thiede, Lake Jackson, TX (US); Morgan A. Springs, Angleton, TX (US); and Van M. Delk, Angleton, TX (US)
Assigned to Dow Global Technologies LLC, Midland, MI (US)
Appl. No. 17/267,171
Filed by Dow Global Technologies LLC, Midland, MI (US)
PCT Filed Aug. 5, 2019, PCT No. PCT/US2019/045173
§ 371(c)(1), (2) Date Feb. 9, 2021,
PCT Pub. No. WO2020/040972, PCT Pub. Date Feb. 27, 2020.
Claims priority of provisional application 62/720,197, filed on Aug. 21, 2018.
Prior Publication US 2021/0301069 A1, Sep. 30, 2021
Int. Cl. C08G 18/76 (2006.01); C08G 18/42 (2006.01)
CPC C08G 18/7664 (2013.01) [C08G 18/4277 (2013.01); C08G 2110/005 (2021.01); C08G 2110/0008 (2021.01); C08G 2110/0083 (2021.01)] 14 Claims
 
1. A flexible polyurethane foam comprising a reaction product of a reaction mixture that comprises
a) a polyol mixture that comprises
i) 45 to 80 weight-%, based on the weight of the polyol mixture, of an ethylene oxide copolymer containing 45 to 70% by weight polymerized ethylene oxide based on the total weight of the ethylene oxide copolymer, or mixture of two or more thereof, the ethylene oxide copolymer or mixture thereof having a number average hydroxyl functionality of 2 to 4 and an average hydroxyl equivalent weight of 175 to 600;
ii) 10 to 30 weight-%, based on the weight of the polyol mixture, of a propylene oxide polymer containing at least 70% by weight polymerized propylene oxide based on the total weight of the propylene oxide polymer, a hydroxyl functionality of 2 to 4 and a hydroxyl equivalent weight of greater than 500 to 2000, or mixture of two or more thereof, and
iii) 5 to 29 weight-%, based on the weight of the polyol mixture, of a liquid polyester polyol having a hydroxyl functionality of 2 to 4 and a hydroxyl equivalent weight of 175 to 900 with the proviso that the hydroxyl equivalent weight is 175 to 600 when the polyester polyol is a polycaprolactone, or a mixture of two or more thereof;
b) water in an amount of 1 to 4 parts by weight per 100 parts by weight of the polyol mixture;
c) an aromatic polyisocyanate that comprises polymeric diphenylmethane isocyanate (MDI), in an amount sufficient to provide an isocyanate index of 50 to 120;
d) at least one urethane catalyst and
e) at least one foam-stabilizing surfactant.