Polyhydroxy Alkanoates

 Polyhydroxyalkanoates (PHAs) comprise a gaggle of natural perishable polyesters that area unit synthesized by microorganisms. However, many disadvantages limit their competition with ancient artificial plastics or their application as ideal biomaterials. These disadvantages embrace their poor mechanical properties, high cost, restricted functionalities, incompatibility with standard thermal process techniques and status to thermal degradation. to avoid these drawbacks, PHAs got to be changed to make sure improved performance in specific applications. during this review, well-established modification strategies of PHAs area unit summarized and mentioned. The improved properties of PHA that blends with natural raw materials or alternative perishable polymers, as well as starch, polysaccharide derivatives, lignin, poly(lactic acid), polycaprolactone and totally different PHA-type blends, area unit summarized. The functionalization of PHAs by chemical modification is represented with relation to 2 necessary synthesis approaches: block copolymerization and graft copolymerization. The dilated utilization of the changed PHAs as engineering materials and also the medicine significance in numerous areas are addressed . Polymers from renewable resources have gained vital attention in recent decades thanks to environmental problems and also the realization of restricted crude resources. Among the natural polymers, polyhydroxyalkanoates (PHAs) comprise a family of perishable polyesters that area unit made by an in depth kind of microorganisms for animate thing carbon and energy storage purpose PHA synthesis is promoted by unbalanced growth throughout the fermentation and accumulation of PHA granules as a part of a survival mechanism of the microbes.