A tissue sealant that includes the reaction product of (a) a polyol (b) a polyisocyanate and (c) an alkoxy silane having the formula: (R1R2R3)—Si—CH2—Z where (i) Z is an —OH, —SH, —NCO, or —NHR4 group, where R4 is hydrogen, an alkyl group, or an aryl group and (ii) each R1, R2, and R3, independently, is H, an alkoxy group, an alkyl group, a heteroalkyl group other than an alkoxy group, an aryl group, or a heteroaryl group, with the proviso that at least two of R1, R2, and R3 are alkoxy groups, the relative amounts of the polyol, polyisocyanate, and alkoxy silane being selected such that the reaction product comprises free isocyanate groups. The tissue sealant is moisture-curable and biodegradable in a physiological environment.
