Superhydrophobic films can be prepared from a stream of plastic waste (i.e., derived from post-consumer and/or industrial waste) by a method comprising: dissolving first semi-crystalline polymers in a solvent to form solution1; pre-heating a solid substrate to below a boiling point of the solvent; applying solution1 onto the substrate using spin-casting to obtain a porous blended-polymer layer with fragile structure; annealing the porous blended-polymer layer to above the melting point of the first semi-crystalline polymers to strengthen the porous blended-polymer layer's internal structure by closing pores and decreasing surface roughness, thereby obtaining a strong non-porous base support layer; and dissolving second semi-crystalline polymer in a solvent to form solution2; pre-heating the non-porous base layer to a temperature below a boiling point of the solvent; applying solution2 onto the non-porous base layer to obtain a top porous layer crosslinked with the non-porous base layer; and peeling off the freestanding superhydrophobic film.

A repair solution for a wind turbine blade is described. The repair solution includes the application of a layer of viscous coating material to the section of the blade to be repaired, which is cured to form a repaired surface. The layer of viscous coating material may be temporarily covered during the curing process using a film of Low Surface Energy material, to prevent defects in the repaired surface from dust, insects, etc. Additionally or alternatively, a temporary shield may be erected adjacent the curing layer of coating material, to allow for the control of the temperature and/or humidity levels of the region adjacent the curing material, to provide for more effective control of the curing process and to allow for repairs to be carried out for a wider process window.