The invention generally relates to novel polymers (SMAMPs) and their syntheses and use. The polymers exhibit promising properties of AMPs. In particularly, for example, a ring-opening metathesis polymerization (ROMP) platform was developed that allows syntheses of SMAMPs that employ a minimum number of norbornene-based building blocks and/or enable easy and independent variation of hydrophobic and hydrophilic groups in the monomer units and/or along the polymeric backbone to finetune and select desirable properties of the polymers.