PHA applications

Solution (a) The system consists of two nonreacting species in two pha application of Eq. (15.33) yields... 

In recent years, PHA have rapidly attracted interest from both research and industry. This chapter presents the recent advances of PHA applications in the medical, aquacultural and agricultural fields, and also sheds some light on the use of PHA in new areas such as nanomedicine, biosurfactants and bactericidal agents. 

High-value-added PHA applications should be developed simultaneously, especially the implant biomaterials that have begun to be recognized by the FDA. In addition, chiral monomers should be further exploited for medical usages (Fig. 7). So far, only 3HB and its derivatives have been studied and have revealed obvious therapeutic efforts, more monomers should be tested for medical efficacy. 

However, to date, few studies have been performed on this subject, and despite its potential, this PHA application still seems to be far from commercial utilization. 

Biofuels including ethanol and biodiesel have always been controversial regarding food vs fuel and fuel vs arable land. PHA-based biofuel production from wastewater or from activated sludge enjoys the advantages of wastewater treatment accompanied by energy generation. These results unlock a new area for PHA application in the energy sector. 

PHA applications as bioplastics, fine chemicals, implant biomaterials, medicines, and biofuels have been researched for many years. Bacterial PHA synthesis has been found... 

Figure 16.10 Polyhydroxyalkanoates (PHA) production and application as bioplastics and biofuels will close the PHA application cycle, leading to reduced COj emission. Left picture al and bl, combustion of fuel ethanol bl and bl, combustion of HBME. ...

Achieve controllable PHA synthesis (homopolymers, random and block copolymers, functional polymers) in large scale Microbial processes often produce inconsistent ratios of monomers in PHA copolymers. This significantly affects PHA applications. Technology must be developed to control the PHA micro and macrostructures so that all microbial PHA have consistent structures and properties ... 

Turning low cost PHA into functional PHA This will save a lot of efforts to reduce PHA production cost. To achieve functional PHA, applications must be identified that make good use of unique PHA properties including biodegradability, biocompatibility, high Mw, and ease of making block copolymerization. 

Green nanocomposites based on PHAs appear as the next generation of environmentally-friendly materials and broaden the range of PHAs applications by enhancing the polymer properties (ductility, melt viscosity, thermal stability). Thus, more appropriate new macromolecular architectures and nanoparticle-based systems should allow, in the near future, the limits of these materials (high crystallinity, brittleness, poor thermal stability) to be overcome. 

Williams SF, Martin DP, Horowitz DM, Peoples OP. PHA applications addressing the price performance issue I. Tissue engineering. Int J Biol Macromol 1999 25 111-121. 

The cost for the production of PHA is still too high for application for biodegradable packaging. High value added applications, especially biomedical application and fine chemical application, may be realistic for the current PHA applications. Many efforts have been made in this area. 

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