Four pre-weighed 2"x4" stainless steel coupons, one for each cleaner tested, were contaminated with a 50/50 blend of Part A and Part B polyurethane foam after mixing at high speed with a drill press in a beaker. Coupons were immediately scrapped to remove a majority of the polyurethane foam to reflect soil levels observed in the images provided by the client. Dirty weights were recorded after soiling the coupons. Cleaners were tested at 100% concentration, and methyl acetate was utilized as a control based on previous efficacy testing performed by the client. Each coupon was immersed for five minutes at room temperature (68F). Final weights and visual rankings were taken after coupons were air-dried at room temperature (68F). The following key was utilized for visual rankings:
| Score
|
Description
|
| 1
|
Clean/ completely removed
|
| 2
|
Mostly removed
|
| 3
|
Partial removal
|
| 4
|
Some removal
|
| 5
|
Initial dirty/No removal
|
| Cleaner
|
Initial wt. of cont.
|
Final wt. of cont.
|
% Cont Removed
|
Initial Visual Rating
|
Final Visual Rating
|
| Stasol
|
0.7292
|
0.4569
|
37.34
|
5
|
3.5
|
| Soy Clear 1500
|
0.4550
|
0.5532
|
-21.58
|
5
|
5
|
| Sky Kleen 1000
|
0.5450
|
0.4153
|
23.80
|
5
|
3.5
|
| Methyl Acetate
|
1.0833
|
0.0756
|
93.02
|
5
|
1.5
|
Stasol and Sky Kleen 1000, both dibastic ester mixtures, showed some effectiveness visually but had under 50% removal. The control, Methyl acetate, had a 93% removal and visually looked the cleanest after five minutes of cold immersion cleaning. Based on previous testing of Stasol and Sky Kleen 1000, heat (between 120-140F) improves the efficacy of these products.
Based on this testing, additional products, solvents, and solvent blends will be added to future testing, and Soy Clear 1500 will not be tested going forward due to poor performance with no removal.
Stasol and Sky Kleen 1000 were somewhat effective at removing the polyurethane foam from the stainless steel coupons. The next round of testing will include heated immersion, and additional products will be added to the list of products to test unheated for preliminary evaluations.