Chitosan preparation
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Transcript of Chitosan preparation
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Preparationof
Chitosan
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Purified Chitin
55 % NaOH Solution
Water bath at 95 °C for 4 hours
Chitosan
Preparation of Chitosan
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Chitosan Preparation
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Chitosan Preparation
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Chitosan Preparation
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ChitinAdding 50% NaOH
Boiled at 100°C for 2 hours
Washed continuously with the 50% NaOH and filtered
Chitosan
Deacetylation
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Chitosan nanofibers were also produced by the electrospinning of chitin solutions using 1,1,1,3,3,3- hexafluoro-2-propanol (HFIP) as the spinning solvent.
Fiber diameters ranged between 50 and 460 nm, but most fibers were smaller than 200 nm.
Electrospinning
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Preparation of Chitosan
i. The chitin (10g) was put into 50% NaOH at 60°C for 8h to prepare crude chitosan.
ii. After filtration, the residue was washed with hot distilled water at 60°C for three times.
iii. The crude chitosan (4.1g) was obtained by drying in an air oven at 50°C overnight.
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Preparation of Chitosan
I. Chitin is treated with 30 ml of 40% sodium hydroxide solution at 105 C for 60, 90 and 120 min, respectively.
II.After filtration, washing to neutral with deionized water and freeze drying, the corresponding chitosan obtained
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Nanowhisker a type of filamentary crystal (whisker) with
cross sectional diameter ranging from 1 to 100 nm and length
to diameter ratio >100.
Nanowhisker
Needle or short rod-like structure
Average length of 250 nm
It can be several dozen times stronger
than regular crystals and can
demonstrate considerable flexibility
and corrosion resistance.
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Chitin nanocrystals are prepared from chitin powder by using acid hydrolysis with sulfuric acid and phosphoric acid.
The prepared nanocrystals were characterized and compared with nanocrystals prepared by conventional HCl hydrolysis.
Nanocrystal
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