Trial Purpose:
To test the efficacy of non HAP/VOC exempt alternative solvents to manually remove three types of polymers from stainless steel.
Date Run:
11/14/2024Experiment 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, 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 |
| Dimethyl Carbonate | 7195 NF Alum | 0.018 | 0 | 100 | 93.76 | 92.09 | 40 | 37 | 42 |
| 0.0318 | 0.0032 | 89.9371 | 30 | ||||||
| 0.0496 | 0.0043 | 91.3306 | 41 | ||||||
| 7229 | 0.0341 | 0.0043 | 87.39 | 88.93 | 52 | 61 | |||
| 0.0536 | 0.006 | 88.806 | 67 | ||||||
| 0.0468 | 0.0044 | 90.5983 | 65 | ||||||
| 7223 | 0.0789 | 0.0065 | 91.7617 | 93.57 | 19 | 28 | |||
| 0.1157 | 0.0109 | 90.5791 | 37 | ||||||
| 0.1043 | 0.0017 | 98.3701 | 28 | ||||||
| Propylene Carbonate | 7195NF Alum | 0.023 | 0.0013 | 94.3478 | 90.11 | 86.61 | 132 | 146 | 96 |
| 0.0353 | 0.0051 | 85.5524 | 165 | ||||||
| 0.0418 | 0.004 | 90.4306 | 140 | ||||||
| 7229 | 0.0181 | 0.0068 | 62.4309 | 73.04 | 48 | 72 | |||
| 0.056 | 0.0142 | 74.6429 | 67 | ||||||
| 0.049 | 0.0088 | 82.0408 | 100 | ||||||
| 7223 | 0.1765 | 0.0076 | 95.6941 | 96.69 | 140 | 71 | |||
| 0.2276 | 0.0016 | 99.297 | 26 | ||||||
| 0.1338 | 0.0066 | 95.0673 | 46 | ||||||
| Tert Butyl Acetate | 7195NF Alum | 0.0625 | 0.0082 | 86.88 | 88.8 | 92.95 | 75 | 55 | 71 |
| 0.0537 | 0.0042 | 92.1788 | 43 | ||||||
| 0.0561 | 0.0071 | 87.344 | 46 | ||||||
| 7229 | 0.0518 | 0.0061 | 88.2239 | 92.69 | 102 | 96 | |||
| 0.0575 | 0.0079 | 86.2609 | 126 | ||||||
| 0.0448 | -0.0016 | 103.571 | 60 | ||||||
| 7223 | 0.1935 | 0.0081 | 95.814 | 97.37 | 57 | 63 | |||
| 0.1567 | 0.005 | 96.8092 | 61 | ||||||
| 0.1953 | 0.001 | 99.488 | 71 | ||||||
| Methyl Acetate | 7195 NF Alum | 0.0716 | 0.003 | 95.8101 | 94.67 | 97.48 | 72 | 46 | 31 |
| 0.0671 | 0.0064 | 90.462 | 43 | ||||||
| 0.0440 | 0.001 | 97.7273 | 23 | ||||||
| 7229 | 0.0953 | 0.0012 | 98.7408 | 98.9 | 30 | 40 | |||
| 0.0931 | 0.0003 | 99.6778 | 44 | ||||||
| 0.1042 | 0.0018 | 98.2726 | 45 | ||||||
| 7223 | 0.1808 | 0.0012 | 99.3363 | 98.87 | 9 | 8 | |||
| 0.1693 | 0.0018 | 98.9368 | 7 | ||||||
| 0.0902 | 0.0015 | 98.337 | 8 | ||||||
| Acetone | 7195 NF Alum | 0.0691 | 0.0003 | 99.5658 | 99.6362 | 99.57 | 11 | 17 | 12 |
| 0.0668 | 0.0000 | 100.0000 | 8 | ||||||
| 0.0913 | 0.0006 | 99.3428 | 32 | ||||||
| 7229 | 0.0639 | 0.0000 | 100.0000 | 99.3103 | 12 | 10 | |||
| 0.0522 | 0.0008 | 98.4674 | 10 | ||||||
| 0.0559 | 0.0003 | 99.4633 | 8 | ||||||
| 7223 | 0.2930 | 0.0000 | 100.0000 | 99.7637 | 8 | 8 | |||
| 0.1989 | 0.0006 | 99.6983 | 8 | ||||||
| 0.2456 | 0.0010 | 99.5928 | 8 |
Propylene Carbonate did not evaporate in 30 mins post cleaning, so the coupons tested with propylene carbonate were dried with the 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:
Acetone is the most effective solvent in removing the three polymers from stainless steel based on the high percentage of soil removed as well as it taking the least amount of time on average to manual remove all visible soil from each coupon. Acetone is closely followed by Methyl Acetate for effectiveness based on the high percentage of soil removed and taking a short amount of time on average. Dimethyl Carbonate also performed well gravimetrically but took longer than both Methyl acetate and Acetone. Propylene Carbonate is the least effective based on having the lowest percentage of soil removed and taking the most time to manually remove all visible soil from each coupon. Tert Butyl Acetate is equally effective as Dimethyl Carbonate based on the percentage of soil removed, however it took longer than Dimethyl Carbonate to manually remove all visible soil from each coupon and took quite a bit of elbow grease.
