Polyurethane material, process for preparing such material and protective cover for wind turbine blade

A preformed protective cover for a wind turbine blade, wherein the preformed protective cover is made of a polyurethane material prepared from a polyol, butanediol, and an isocyanate, wherein the preformed protective cover is adapted to be attached along at least a part of a longitudinal edge of the wind turbine blade by adhesion of an inside of the preformed protective cover to a surface of the longitudinal edge of the wind turbine blade, wherein the preformed protective cover is elongated in a longitudinal direction and has an U-formed cross-section, wherein the preformed protective cover includes a central cover section extending in the longitudinal direction and two peripheral cover sections extending in the longitudinal direction at either side of the central cover section, respectively, wherein the central cover section has a minimum thickness of at least 1 millimetre, and each peripheral cover section has a thickness decreasing from a maximum thickness of at least 1 millimetre to a minimum thickness of less than ½ millimetre,

• wherein the polyol, butanediol, and isocyanate are used in a ratio by weight polyol:butanediol:isocyanate of 100:(3 to 5):(30 to 35).