Polyhydroxyalkanoates biopolymers

Kim S., Dale B E. Life cycle assessment study of biopolymers (polyhydroxyalkanoates) derived from no-tilled corn. The International Journal of Life Cycle Assessment 10 (2005) 200. 

Fermentation of Sweet Sorghum into Added Value Biopolymer of Polyhydroxyalkanoates (PHAs)... 

Metabolix Inc., is a private firm based in Cambridge, Massachusetts, USA, that was spun out of the Massachusetts Institute of Technology in 1992 and acquired biopolymer technology from Monsanto Inc. in 2001. Metabolix began its first commercial production of organic polyhydroxyalkanoate (PHA) resin, based on corn sugar in 2005 at an undisclosed location in the Midwest. The plant was expected to produce around 100 tonnes of material in 2005 and close to 1000 tonnes in 2006. 

Ionic liquids have also been used to dissolve other biologically occurring polymers. Wool keratin, an unbranched polymer of amino acids, has been reported to dissolve in [C4mim][Cl] up to a concentration of 11 wt% at 130 °C. Chitin has been dissolved in C4mim Ac up to 6 wt% at 110 °C [132], Proctor and Gamble has a patent on ionic liquids for the dissolution of biopolymers including chitin, chitosan, elastin, collagen, keratin and polyhydroxyalkanoate [133],... 

Steinbtichel, A. (2001) Perspedives for biotechnological production and utilization of biopolymers metabolic engineering of polyhydroxyalkanoate biosynthesis pathways as a successful example. Macromol. Biosci., 1,1-24. 

The synthesis of bacterial storage compounds is reviewed in Chapter 10, focusing on two systems, namely polyhydroxyalkanoic acids and cyanophycin. Bacterial storage compounds are very interesting biopolymers having attractive material properties, sometimes similar to those of the petrochemical-based polymers. 

Polymers derived from renewable resources (biopolymers) are broadly classified according to the method of production (1) Polymers directly extracted/ removed from natural materials (mainly plants) (e.g. polysaccharides such as starch and cellulose and proteins such as casein and wheat gluten), (2) polymers produced by "classical" chemical synthesis from renewable bio-derived monomers [e.g. poly(lactic acid), poly(glycolic acid) and their biopolyesters polymerized from lactic/glycolic acid monomers, which are produced by fermentation of carbohydrate feedstock] and (3) polymers produced by microorganisms or genetically transformed bacteria [e.g. the polyhydroxyalkanoates, mainly poly(hydroxybutyrates) and copolymers of hydroxybutyrate (HB) and hydroxyvalerate (HV)] [4]. 

The book addresses the most important biopolymer classes like polysaccharides, lignin, proteins and polyhydroxyalkanoates as raw materials for bio-based plastics, as well as materials derived from bio-based monomers like lipids, poly(lactic acid), polyesters, polyamides and polyolefines. Additional chapters on general topics - the market and availability of renewable raw materials, the importance of bio-based content and the issue of biodegradability - will provide important information related to all bio-based polymer classes. 

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