Biodegradable thermoplastic composite material

摘要

moulding processes. The composite material 36 includes a major percentage of natural-starch polyester polymer and a minor percentage of powdered chemically-untreated straw. The straw being untreated is essential to provide uniform solidity to the finished composite material 36, thereby allowing use of the composite in conventional extruding and injection moulding. The biodegradable thermoplastic composite material 36 is ideally suited for disposable practice mortar rounds 10 and obturation disks or wadding of shotgun cartridges, thus dispensing with the need for retrieval following discharge.