Time Alkali
Lithium hydroxide Sodium hydroxide Potassium hydroxide
0.1N 0.5N 1N 2N 0.1N 0.5N 1N 2N 0.1N 0.5N 1N 2N
2 days 49 49 49 49 48 48 48 48 48 48 48 49
7 days 50 52 52 54 49 50 52 53 50 51 53 54
15 days 53 55 56 57 53 55 56 56 54 55 56 57
30 days 57 58 59 58 55 56 57 58 55 56 57 59
 45 days 59 59 60 60 58 59 60 60 57 59 61 61
60 days 58 59 60 61 59 60 61 61 58 60 61 60
Table 2: Hardness (shore-D) testing of polyvinyl acetate-Epoxy blend foam after soaking of different alkalis at different times.