Poly β - hydroxybutyrate - co - β - hydroxy valerate (PHBV) is a biodegradable polymer obtained by the copolymerisation of 3–hydroxybutanoic acid and 3–hydroxypentanoic acid.
Nylon 2–nylon 6 is an alternating polyamide copolymer of glycine and amino caproic acid and is biodegradable.