| abstract |
Aromatic polyester polyols with high functionality, moderate viscosity, and high aromatic content suitable as the sole polyol in the production of polyurethane foams without the use of any polyether polyols are disclosed. This unique combination of properties makes them suit for use as the sole polyol in the production of polyurethane foams. With reduction of flame retardants, these foams based on sole aromatic polyol can have E-84 class one fire properties. The aromatic polyester polyols of this invention are characterized as having a functionality of greater than 2.8 while having a moderate viscosity ranging from 4,000-10,000 cps @ 25 C. A typical high functional polyester polyol of the present invention has a hydroxyl number in the range of 320-400, viscosity of 4,000-10,000 cps @ 25 C, functionality of greater than 2.8 and percent phenyl content greater than 14.75. |