| 主权项 |
1. A polyurethane-based sealant comprising a reaction product of a reaction system, the reaction system comprising:
at least one isocyanate; at least one chain extender having two isocyanate-reactive groups per molecule and an equivalent weight per isocyanate-reactive group of less than 400; and at least one polyester polyol, the polyester polyol being a reaction product of a polyester reaction mixture consisting essentially of:
one or more hydrophobic monomers comprising one or more hydroxyl stearic acids or esters thereof, or hydroxymethylated fatty acids or esters thereof;one or more organic diacids or methyl esters thereof comprising linear or branched compounds represented by HOOZ—X—ZOOH, where X indicates aliphatic linkages, aromatic linkages, or mixtures thereof, of between 2 carbons and 20 carbons, and Z is selected from carbon, phosphorous, or sulfur;one or more diols having a molecular weight between about 62 g/mol and about 1000 g/mol, and selected from ethylene glycol, propylene glycol, 1,2-butylene glycol, 2,3-butylene glycol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, 1,6-hexanediol, neopentylglycol, 1,2-ethylhexyldiol, 1,5-pentanediol, 1,10-decanediol, 1,3-cyclohexanedimethanol, 1,4-cyclohexanedimethanol (CHDM), or combinations thereof; andone or more polyols having a functionality of at least 3 and a molecular weight below about 400 g/mol. |
