Most synthetic polymers are non-biodegradable — they persist in the environment for hundreds of years (plastic pollution crisis). Solutions: biodegradable polymers, recycling, incineration with energy recovery.

PHBV (poly-beta-hydroxybutyrate-co-beta-hydroxyvalerate): Copolyester produced by bacteria. Ratio of HB to HV controls flexibility. Fully biodegraded by soil bacteria. Used for packaging, drug delivery, surgical sutures, orthopedic implants.

Nylon-2-nylon-6: Copolymer of glycine (2C amino acid) and 6-aminocaproic acid (6C). The polyamide structure resembles proteins → naturally occurring enzymes can degrade it.

PGA (polyglycolic acid) and PLA (polylactic acid): Biodegradable polyesters used in absorbable surgical sutures. PLA made from corn starch → truly renewable resource.

For JEE: Know PHBV (most commonly asked), its biodegradable nature, and why normal plastics like PE/PVC are non-biodegradable (no enzyme in nature can break C-C backbone efficiently).