The design of secondary conformation and chemically rich polymers that mimic natural biopolymers in function and structure is an important goal. Polymers based on meta-phenylene ethynylenes were patterned with polar, cationic, and nonpolar alkyl groups along the backbone with a repeat similar to amphiphilic beta-sheet peptides. These polymers were characterized at the air-water interface by Langmuir techniques and found to adopt an edge-on, amphiphilic, extended conformation with an area per repeat unit of similar to42 Angstrom. They are also membrane active as shown by phospholipid vesicle lysis experiments.