Patent ID: 7771806

Claim:
A film prepared from a urea/urethane polymer comprising (a) repeating units derived from a hydroxy-terminated copolymer prepared from tetrahydrofuran and one or both of an alkylene oxide and a cyclic acetal and (b) repeating units derived from a polyisocyanate; wherein the urea/urethane polymer contains less than about 2 mole percent of urea units described by the formula —R—N(R 2 )—C(O)—N(R 2 )—R 1 —; wherein R is an aromatic hydrocarbon radical, R 1 is an aliphatic hydrocarbon radical, and R 2 is H or an amide group that is described by the formula —C(O)—N(R 2 )—R—; and wherein the tetrahydrofuran is described by the formula in which any one of the R 4 s may be a C 1 to C 4 alkyl radical with the remaining R 4 s being hydrogen.