Norbornyl benzocyclobutene ladder polymer composite membranes for fluid separation

A composite membrane comprising:

• a mesoporous membrane support layer comprising a plurality of pores extending through the support layer, said support layer having a first side, a second side, and a thickness;
• and
• optionally, a gutter layer comprising a permeable elastic polymer, said gutter layer having a first side, a second side, and a thickness;
• a thin film membrane selective layer comprising a plurality of ladder polymer chains, said selective layer having a first side, a second side, and a thickness;
• wherein:
• when the gutter layer is present, the second side of the support layer is disposed along the first side of the gutter layer, and the second side of the gutter layer is disposed along the first side of the selective layer;
• when the gutter layer is absent, the second side of the support layer is disposed along the first side of the selective layer;
• and
• the thickness of the selective layer is less than about 10 microns.