We are attempting to degum silk from the Bombyx mori cocoons and are concerned that we did not remove an adequate amount of sericin. We used a 50mL solution of 0.02M NaCO3 and 0.5 grams of technical grade silk. Originally, we submerged the silk in the solution and then boiled it for 30 minutes and washed the silk for 20 minutes. We used a pre-made 0.02M solution and heated it using a water bath. However, it didn't appear to degum properly. Any ideas as to what may have gone wrong?