Swelling capacity was used to access the quality characteristic.
The swelling capacity was determined according to
the method of Wang [22] with slight modification. Take
M(g) of EWP into centrifuge tube (M1). Uniform mixed
the solution after adding water. Take solution in water bath
at 24 C and add SDS-lactic acid for 20 min in 24 C water
bath.. Centrifuge the solution at 300 min/r for 3 min.
Weigh the centrifuge tube and residuum (M2).