|
Poly(hexamethylene Carbonate)
Poly(hexamethylene carbonate) (PHC) is an organic polymer. It can be biodegredated to form adipic acid and di(6-hydroxyhexyl) carbonate by ''Roseateles depolymerans ''Roseateles depolymerans'' is an aerobic photosynthetic bacterium from the genus ''Roseateles'', which was isolated from river water (Hanamuro River, Tsukuba, Japan). ''R. depolymerans'' is a bacteriochlorophyll ''a''-containing obligate aerob ...'' 61A. PHC can be synthesized to terminate in primarily hydroxyl groups or methyl carbonate groups depending on the concentrations of monomers during synthesis. PHC with the hydroxyl end groups has less thermal stability than PHC with methyl carbonate end groups. The hydroxyl group allow for an unzipping reaction to take place in which the polymer chain bends back on itself and the hydroxyl group reacts with an acetyl mid chain, resulting in a shorter chain and a looped molecule. This type of degradation quickly shorten the length of the PHC. References Organic poly ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organic Polymer
A polymer (; Greek '' poly-'', "many" + ''-mer'', "part") is a substance or material consisting of very large molecules called macromolecules, composed of many repeating subunits. Due to their broad spectrum of properties, both synthetic and natural polymers play essential and ubiquitous roles in everyday life. Polymers range from familiar synthetic plastics such as polystyrene to natural biopolymers such as DNA and proteins that are fundamental to biological structure and function. Polymers, both natural and synthetic, are created via polymerization of many small molecules, known as monomers. Their consequently large molecular mass, relative to small molecule compounds, produces unique physical properties including toughness, high elasticity, viscoelasticity, and a tendency to form amorphous and semicrystalline structures rather than crystals. The term "polymer" derives from the Greek word πολύς (''polus'', meaning "many, much") and μέρος (''meros'', meani ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Biodegradation
Biodegradation is the breakdown of organic matter by microorganisms, such as bacteria and fungi. It is generally assumed to be a natural process, which differentiates it from composting. Composting is a human-driven process in which biodegradation occurs under a specific set of circumstances. The process of biodegradation is threefold: first an object undergoes biodeterioration, which is the mechanical weakening of its structure; then follows biofragmentation, which is the breakdown of materials by microorganisms; and finally assimilation, which is the incorporation of the old material into new cells. In practice, almost all chemical compounds and materials are subject to biodegradation, the key element being time. Things like vegetables may degrade within days, while glass and some plastics take many millennia to decompose. A standard for biodegradability used by the European Union is that greater than 90% of the original material must be converted into , water and minerals b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Adipic Acid
Adipic acid or hexanedioic acid is the organic compound with the formula (CH2)4(COOH)2. From an industrial perspective, it is the most important dicarboxylic acid: about 2.5 billion kilograms of this white crystalline powder are produced annually, mainly as a precursor for the production of nylon. Adipic acid otherwise rarely occurs in nature, but it is known as manufactured E number food additive E355. Preparation and reactivity Adipic acid is produced from a mixture of cyclohexanone and cyclohexanol called KA oil, the abbreviation of ketone-alcohol oil. The KA oil is oxidized with nitric acid to give adipic acid, via a multistep pathway. Early in the reaction, the cyclohexanol is converted to the ketone, releasing nitrous acid: :HOC6H11 + HNO3 → OC(CH2)5 + HNO2 + H2O Among its many reactions, the cyclohexanone is nitrosated, setting the stage for the scission of the C-C bond: :HNO2 + HNO3 → NO+NO3− + H2O :OC6H10 + NO+ → OC6H9-2-NO + H+ Side products of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Roseateles Depolymerans
''Roseateles depolymerans'' is an aerobic photosynthetic bacterium from the genus ''Roseateles'', which was isolated from river water (Hanamuro River, Tsukuba, Japan). ''R. depolymerans'' is a bacteriochlorophyll ''a''-containing obligate aerobe in the β-subclass of the Proteobacteria. The cells are motile, straight rods, and they contain poly-β-hydroxybutyrate granules. ''R. depolymerans'' is characterised by the ability to biodegrade the material poly(hexamethylene carbonate) (PHC), and some other biodegradable plastics Biodegradable plastics are plastics that can be decomposed by the action of living organisms, usually microbes, into water, carbon dioxide, and biomass. Biodegradable plastics are commonly produced with renewable raw materials, micro-organisms, .... References External linksType strain of ''Roseateles depolymerans'' at Bac''Dive'' - the Bacterial Diversity Metadatabase Comamonadaceae Bacteria described in 1999 {{betaproteobacteria-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organic Polymers
A polymer (; Greek '' poly-'', "many" + '' -mer'', "part") is a substance or material consisting of very large molecules called macromolecules, composed of many repeating subunits. Due to their broad spectrum of properties, both synthetic and natural polymers play essential and ubiquitous roles in everyday life. Polymers range from familiar synthetic plastics such as polystyrene to natural biopolymers such as DNA and proteins that are fundamental to biological structure and function. Polymers, both natural and synthetic, are created via polymerization of many small molecules, known as monomers. Their consequently large molecular mass, relative to small molecule compounds, produces unique physical properties including toughness, high elasticity, viscoelasticity, and a tendency to form amorphous and semicrystalline structures rather than crystals. The term "polymer" derives from the Greek word πολύς (''polus'', meaning "many, much") and μέρος (''meros'', meaning "p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
