The effect of a dilute urea solution, an acid simulated perspiration solution, and distilled water on a polyurethane coated fabric
This research has investigated the effects of a dilute urea solution, an acid-simulated perspiration solution, and distilled water on a polyurethane-coated fabric. Investigations were made into the feasibility of using the Glass Plate Method, where treated samples were heated between glass plates and the LaunderOmeter® Method where samples were treated with solutions in an enclosed system in a constant temperature bath. The degradative effects of the solutions, when used with the Glass Plate Method, were measured by flex and surface abrasion and the degradative effects of the solutions, when used with the LaunderOmeter® Method, were measured by surface abrasion. The pH was observed before and after treatments in the LaunderOmeter® .
It was found that the urethane film of the test fabric could be completely decomposed with all three solutions when treated at 95°C for six hours in the LaunderOmeter®. However, those samples treated with urea had higher abrasion resistance and appeared less decomposed visually. This was in conflict with reports that the addition of urea to distilled water would increase the rate of hydrolysis, and could be used to simulate perspiration. This is assuming that the effects of the solutions were indeed causing hydrolysis.
The LaunderOmeter® Method was found to be more controllable than the Glass Plate Method. Replications of treatments at 72°C for two hours were carried out on the polyurethane synthetic leathers using the LaunderOmeter® Method. Again, the urea-treated samples demonstrated a higher abrasion resistance. Distilled water and the acid-simulated perspiration solution gave comparable results.