High molecular weight hydrophobic polyol
A cured composition including a reaction product of a mixture that includes an isocyanate component having one or more isocyanates and an isocyanate-reactive component having a butylene oxide based polyol, which has a number average molecular weight greater than 2,000 g/mol and less than 8,000 g/mol and a nominal hydroxyl functionality from (2) to (4). At least (50) wt % of a total weight of alkylene oxides used to form the butylene oxide based polyol is butylene oxide. An isocyanate index of the mixture is from (90) to (150). The cured composition in a cured state exhibits a first tan delta peak between a first temperature range of 50° C. to 0° C. and a second tan delta peak between a second temperature range of 75° C. and 150° C., according to a tan delta plot over a range of temperatures, and a value of the first tan delta peak and a value of the second tan delta peak each represents a ratio of a loss modulus of the cured composition and a storage modulus of the cured composition at a specific temperature within the range of temperatures, as measured according to dynamic mechanical thermal analysis. The values of the first and the second tan delta peaks are from (0.10) to (0.90).
1. A cured composition, comprising:
a reaction product of a mixture that includes an isocyanate component having one or more isocyanates and an isocyanate-reactive component having a butylene oxide based polyol, which has a number average molecular weight greater than 2,000 g/mol and less than 8,000 g/mol and a nominal hydroxyl functionality from 2 to 4, at least 50 wt % of a total weight of alkylene oxides used to form the butylene oxide based polyol being butylene oxide, and an isocyanate index of the mixture being from 90 to 150; and
the cured composition in a cured state exhibits a first tan delta peak between a first temperature range of −50° C. to 0° C. and a second tan delta peak between a second temperature range of 75° C. and 150° C., according to a tan delta plot over a range of temperatures, and a value of the first tan delta peak and a value of the second tan delta peak each represents a ratio of a loss modulus of the cured composition and a storage modulus of the cured composition at a specific temperature within the range of temperatures, as measured according to dynamic mechanical thermal analysis, the values of the first and the second tan delta peaks being from 0.10 to 0.90.
2. The composition as claimed in claim 1 , wherein the butylene oxide based polyol is derived from 75 wt % to 100 wt % of butylene oxide, based on a total weight of alkylene oxides, the nominal hydroxyl functionality is 3, and the butylene oxide based polyol is present in an amount from 5 wt % to 100 wt % of a total weight of polyols in the isocyanate-reactive component.
3. The composition as claimed in claim 1 , wherein the number average molecular weight of the butylene oxide based polyol is from 4000 g/mol to 5500 g/mol.
4. The composition as claimed in claim 1 , wherein a volumetric ratio of the isocyanate component to the isocyanate-reactive component is from 0.8:1.2 to 1.2:0.8.
5. The composition as claimed in claim 1 , wherein the isocyanate-reactive component further includes a polyether polyol different from the butylene oxide based polyol and having a nominal hydroxyl functionality of 2.
6. The composition as claimed in claim 1 , wherein the isocyanate component includes from 20 wt % to 100 wt %, based on the total weight of the isocyanate component, of one or more isocyanate terminated prepolymers having an isocyanate group content from 1 wt % to 35 wt %, based on the total weight of the one or more isocyanate terminated prepolymers.
7. The composition as claimed in claim 1 , wherein the butylene oxide based polyol is prepared using from one to ten separate stages, each stage including the addition of butylene oxide.
8. The composition as claimed in claim 1 , wherein the isocyanate-reactive component includes from 2 wt % to 25 wt % of dipropylene glycol, based on the total weight of the isocyanate-reactive component.
9. A polyurethane based adhesive, comprising the cured composition as claimed in claim 1 .
10. A polyurethane based coating, comprising the cured composition as claimed in claim 1 .