摘要 |
<p>U7 A prepolymer curable with a hydroxyl or amine functional curative to form a polyurethane elastomer composition having low heat buildup characteristics is disclosed. Specifically, the polyurethane prepolymer has terminally reactive isocyanate groups and is prepared by reaction of polymeric diol with a stoichiometric excess of a mixture of the 2,6- and 2,4-isomers oftolylene diisocyanate, said mixture containing from about 50 to about 90 wt % of the 2,6- isomer.</p><p>The invention also relates to a polyurethane elastomer composition comprising the aforementioned prepolymer and a curingly effective amount of a curative selected from the group consisting of aromatic diamines, hydroxy functional compounds, and mixtures thereof, and optionally, from about 0.01 to 1 part of catalyst per hundred parts of prepolymer.</p><p>Also disclosed are articles of manufacture produced from the above composition, as well as compositions wherein the mixture contains 40 to 100 wt % of the 2,6- isomer.</p> |