For gas separation membrane
The polyamic acid obtained from BTDA and ODA was reacted with a tertiary amine with 12 or 16 carbons to form a polyamic acid salt coating and dried for testing. While it was thermally imidized and tested. The transmittance of the LB film is an order of magnitude higher than that of the polyimide homogeneous film. The separation coefficient may be an order of magnitude lower due to defects in the LB film. But for the LB film obtained from the 16-carbon tertiary amine, it is possible to maintain a high permeation coefficient while maintaining a high separation coefficient.