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Abstract
Plastic has become a standard part of modern life and has greatly enhanced the quality of life in many ways. Foods last longer on the shelves, items can be cheaply and safely shipped over large distances, and food can be easily packaged for meals in the fast-food, grocery, and coffee industries that allow a bustling society to continually function. But with all of these benefits comes the downside that when plastic waste is mismanaged it accumulates in the environment with deleterious effects on wildlife. More recently microplastics, which result from either weathering of larger plastic items or from direct release of microparticles, have been shown to accumulate in micro and macro fauna with increasing health concerns for humans as well. There is a pressing need for a viable replacement for current commodity thermoplastics that are used in the single use packaging sector, such as polypropylene (PP), polyethylene (PE), and polyethylene terephthalate (PET), that are biologically degradable into nontoxic components that do not introduce persistent microplastics into the environment. Polyhydroxyalkanoates (PHA), a class of aliphatic polyesters produced through fermentation, show much promise for meeting that need. PHA copolymers offer a wide variety of melt and mechanical properties depending on the type and amount of random comonomer incorporated. Further melt blending and reactive extrusion with various polyesters, fillers, and nucleating agents were shown to give properties that allow for a broad spectrum of applications to be targeted by a truly biologically degradable material.