Mechanically Frothed Gel Elastomers and Methods of Making and Using Them
A method of making frothed gel in which no blowing (gas producing) agents are used, and in which non-aqueous gel precursor polyol and additive systems are frothed using a froth mix head, either prior to, or after addition of the isocyonate, depending on desired speed of reaction and cell structure. Isocyanate may be added after the material leaves the froth mix head, in which case it can be added to the froth using a static mixer. No water, or very little water, is used in the process.
1 . A method of making a non-aqueous frothed gel in which no blowing (gas producing) agents are used, and in which non-aqueous gel precursor polyol and additive systems are frothed using a froth mix head, either prior to, or after addition of the isocyanate, the method comprising preparing a mixed Polyol by pre-mixing Polyol, catalyst, mono functional additive, filler and (optionally) pigment, and metering said mixed polyol into the froth mix head.
2 . A method according to claim 1 , which uses no water.
3 . A method according to claim 1 , which uses less than 2% by volume of water.
4 . A method according to claim 1 , wherein polyol is used in the amount of 50%-60%, catalyst is used in the amount of 0%-5%, monofunctional additive is used in the amount of 0%-15%, filler is used in the amount of 0%-20%, pigment is used in the amount of 0%-5%, surfactant is used in the amount of 0%-20%, and isocyanate is used in the amount of 15%-20%.
5 . A method according to claim 1 , wherein the process is carried out at 70°-90° F., 10-40 psi, with a chemical throughput of 20-60 grams/sec, and with a mixer speed of 400-600 RPM.
6 . A mechanically frothed gel comprising polyol in the amount of 50%-60%, in the amount of 0%-5%, monofunctional additive in the amount of 0%-15%, filler in the amount of 0%-20%, pigment in the amount of 0%-5%, surfactant in the amount of 0%-20%, and isocyanate in the amount of 15%-20%.
7 . A mechanically frothed gel according to claim 6 , comprising less than 2% water.
8 . A mechanically frothed gel according to claim 6 , comprising less than 1% water.
9 . A mechanically frothed gel according to claim 6 , having a density of 10-30 Lb/CuFt, a durometer of greater than 70 Shore)), and a rebound time of from 1-600 seconds.