摘要 |
Hydrophobic polyurethane compositions can be used to repair or fill-in surface defects in structural components. The hydrophobic composition can be packaged in two parts, a hydrophobic polyol part and a isocyanate part wherein the polyol part comprises a polyol and a coal tar or pitch composition and the isocyanate part comprises a reactive isocyanate compound. The parts of the composition can be mixed and applied to surface defects of structural members such as railroad ties and can rapidly form a hard, permanent, strongly bonded repair. |