Trial Purpose:
To test the efficacy of other solvents to manually remove three types of polymers from stainless steel
Date Run:
12/04/2024Experiment Procedure:
Three 304 stainless steel coupons were assigned to each of the soils per solvent resulting in a total of 27 coupons total. Each coupon was weighed with a mass balance and had their initial weights recorded. Each coupon was then soiled with its respective polymer and catalyst mixture. To soil each coupon, a pipette was used to apply a 0.5ml of the correct polymer catalyst mixture in a stripe across the middle of the coupons. The stripe of soil was then spread with a paint scraper to apply a thin coating to the bottom half of the coupon. After drying for 30 seconds, the next layer was applied. Each coupon was soiled with a total of 5 layers. After the soil was applied, the coupons were placed in the oven at 325F for 5 mins to cure the polymers. Each coupon had their dirty weights recorded. Each coupon was then timed while manually wiped with a cotton rag dipped in the respective solvent with circular motions. Manual wiping was ceased when all visible soil was removed from a coupon. If all visible soil was not able to be fully removed at 5 mins (300 seconds), cleaning was ceased. Coupons were then left to air dry for 30 mins before recording their clean weights.
Trial Results:
| Cleaner | Soil | Initial wt of cont. | Final wt of cont. | %Cont Removed | % AVG | % Overall | Time until clean | Secs AVG | Secs Overall |
| Ethylene Glycol | 7159NF Alum | 0.0617 | 0.0089 | 85.5754 | 82.86 | 78.35 | 30 | 27 | 39 |
| 0.0971 | 0.0019 | 98.0433 | 24 | ||||||
| 0.0719 | 0.0252 | 64.9513 | 28 | ||||||
| 7229 | 0.0716 | 0.0346 | 51.6760 | 60.24 | 34 | 56 | |||
| 0.0474 | 0.0223 | 52.9536 | 67 | ||||||
| 0.0983 | 0.0235 | 76.0936 | 68 | ||||||
| 7223 | 0.1684 | 0.0015 | 99.1093 | 91.95 | 35 | 33 | |||
| 0.1455 | 0.0288 | 80.2062 | 41 | ||||||
| 0.1817 | 0.0063 | 96.5327 | 22 | ||||||
| Isopropanol | 7195NF Alum | 0.0695 | 0.0002 | 99.7122 | 99.62 | 99.65 | 22 | 16 | 20 |
| 0.0668 | 0.0002 | 99.7006 | 14 | ||||||
| 0.0724 | 0.0004 | 99.4475 | 11 | ||||||
| 7229 | 0.0901 | 0.0006 | 99.3341 | 99.51 | 31 | 35 | |||
| 0.1024 | 0.0004 | 99.6094 | 40 | ||||||
| 0.1217 | 0.0005 | 99.5892 | 34 | ||||||
| 7223 | 0.1950 | 0.0003 | 99.8462 | 99.82 | 10 | 9 | |||
| 0.1823 | 0.0004 | 99.7806 | 8 | ||||||
| 0.1999 | 0.0003 | 99.8499 | 8 |
The Ethylene Glycol did not air dry in 30 mins after the cleaning concluded, so the coupons were dried with a heat gun before taking clean weights.
Success Rating:
Results successful using TACT (time, agitation, concentration, and temperature, as well as rinsing and drying) and/or other cleaning chemistries examined.Conclusion:
Isopropanol (rubbing alcohol) is highly effective in removing all soils from the stainless steel coupons. Ethylene Glycol was effective in removing the 7159 NF Alum and 7223 polymers but was unsuccessful in removing the 7229 polymer.
