title: The chitosan prepared from crab tendon I: the characterization and the mechanical properties.
abstract: Crystalline chitosan was prepared from crab tendon consisting mainly of chitin, including various proteins and calcium phosphates. The crab tendon has high mechanical properties due to its aligned molecular structure. Crab tendon components, i.e. proteins and calcium phosphates, were removed by deacetyl treatment using 50wt% NaOH aqueous solution at 100 degrees C, and a subsequent ethanol treatment. As judged from microscopic observations using an optical polarizer, the treated chitosan remained intact regarding its aligned molecular structure, and had a high tensile strength of 67.9+/-11.4MPa. The tensile strength was further enhanced to 235+/-30MPa by a thermal treatment at 120 degrees C, corresponding to the formation of the intermolecular hydrogen bonds.
authors.affiliation: National Institute for Materials Science, Advanced Materials Laboratory, Namiki 1-1, Tsukuba, 305-0044, Ibaraki, Japan. i_yamaguchi@takichem.co.jp
authors.forename: Isamu
authors.initials: I
authors.lastname: Yamaguchi
authors.forename: Soichiro
authors.initials: S
authors.lastname: Itoh
authors.forename: Masumi
authors.initials: M
authors.lastname: Suzuki
authors.forename: Masataka
authors.initials: M
authors.lastname: Sakane
authors.forename: Akiyoshi
authors.initials: A
authors.lastname: Osaka
authors.forename: Junzo
authors.initials: J
authors.lastname: Tanaka
mesh_terms: D000818:Animals; D001672:Biocompatible Materials / Q000737:chemistry; D002130:Calcium Phosphates / Q000737:chemistry; D002686:Chitin / Q000031:analogs & derivatives* / Q000032:analysis* / Q000737:chemistry*; D048271:Chitosan; D018360:Crystallography, X-Ray; D033364:Decapoda; D000431:Ethanol / Q000494:pharmacology; D006358:Hot Temperature; D006860:Hydrogen Bonding; D012972:Sodium Hydroxide / Q000494:pharmacology; D017550:Spectroscopy, Fourier Transform Infrared; D013696:Temperature; D013710:Tendons / Q000378:metabolism*; D013718:Tensile Strength
chemical_list: D001672:Biocompatible Materials; D002130:Calcium Phosphates; C485828:alpha-tricalcium phosphate; C485830:tetracalcium phosphate; D002686:Chitin; D000431:Ethanol; D012972:Sodium Hydroxide; C485838:calcium phosphate, monobasic, anhydrous; D048271:Chitosan; C020243:calcium phosphate; C485829:calcium phosphate, dibasic, anhydrous