From Chitin to Chitosan - Chitosan Based Hydrogels: Functions and Applications - page 1

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From Chit in to Chitosan
Dayong Teng
CoNTENTS
1.1 Chitin ....................................................................................................................................... 2
1.1.1 Discovery and Origin................................................................................................ 2
1.1.2 Existence...................................................................................................................... 3
1.1.3 General Situation of Research and Production ..................................................... 3
1.2 Deacetylation .......................................................................................................................... 5
1.2.1 Chemical Method ...................................................................................................... 5
1.2.2 Enzyme Method......................................................................................................... 7
1.3 Control of Quality.................................................................................................................. 8
1.3.1 Deacetylation Degree ................................................................................................ 8
1.3.2 Molecular Weight....................................................................................................... 9
1.3.3 Structure Identiication ........................................................................................... 10
1.3.4 Ash Content .............................................................................................................. 11
1.3.5 Nitrogen Content ..................................................................................................... 11
1.3.6 Water Content........................................................................................................... 12
1.4 Physical Properties .............................................................................................................. 12
1.4.1 Structure Characteristic .......................................................................................... 12
1.4.2 Infrared Spectroscopy and Nuclear Magnetic Resonance ................................ 14
1.5 Chemical Properties ............................................................................................................ 17
1.5.1 O-Acylation and N-Acylation ................................................................................ 17
1.5.2 Esteriication Using Inorganic Oxygen Acids...................................................... 18
1.5.3 Etheriication ............................................................................................................ 19
1.5.4 N-Alkylation ............................................................................................................. 21
1.5.5 Oxidation................................................................................................................... 24
1.5.6 Chelation ................................................................................................................... 25
1.5.7 Graft Copolymerization .......................................................................................... 27
1.5.8 Cross-Linking........................................................................................................... 30
1.6 The Standard as Biomaterials ............................................................................................ 31
1.6.1 Standard of Chitosan as Biomaterials................................................................... 31
1.6.2 Status of Chitosan Products ................................................................................... 31
References....................................................................................................................................... 33
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