Polyurethane foams for trench breaker and other applications

摘要

The invention is directed to methods for supporting trench pipes with polyurethane foams which are flotation resistant with sufficient strength and density to provide stability and inhibit erosion at pipeline trench sites, and other uses, wherein at least 50% of the foam is open cell and has a density of approximately 1.3 lbs/ft3 to 3.5 lbs/ft3. The invention also provides methods for making compositions used to make polyurethane foams that exhibit such characteristics.