英文名称:2-Oxepanone, polymer with 1,4-butanediol, .alpha.-hydro-.omega.-hydroxypoly(oxy-1,4-butanediyl) and 1,1-methylenebis4-isocyanatobenzene; 2-Oxepanone, polymer with 1,4-butanediol, .alpha.-hydro-.omega.-hydroxypoly(oxy-1,4-butanediyl) and 1,1-methylenebis4-isocyanatobenzene