Abstract: A biodegradable composite including: (a) a polymeric matrix having a biodegradable polymer; (b) a filler; and (c) an anhydride grafted compatibilizer including one or more biodegradable polymers modified with an anhydride group. The composite may also include (d) polymer additives such as polymer chain extenders or plasticizers. An in situ method of manufacturing the biodegradable composite of the present invention, including the steps of: (a) melting one or more biodegradable polymers in the presence of a functional monomer and a free radical initiator to form a mixture; and (b) adding a filler and polymer additives to the mixture thereby manufacturing the biodegradable composite.