Chitosan and modified chitosan membranes I. Preparation and characterisation

✍ Scribed by Hal S. Blair; Dr John Guthrie; Tak-Kau Law; Paul Turkington

• Publisher: John Wiley and Sons
• Year: 1987
• Tongue: English
• Weight: 723 KB
• Volume: 33
• Category: Article
• ISSN: 0021-8995
• DOI: 10.1002/app.1987.070330226

✦ Synopsis

Chitosan has been prepared from prawn shell and crab shell chitin. The molecular weight of the material derived from prawn shells is higher than that obtained from crab shell. The molecular weight, tensile strength, elongation at the break, and hydrophilic properties of chitosan are extremely dependent on the degree of deacetylation achieved when chitin is hydrolyzed to chitasan. Graft copolymers have been prepared with chitosan and a series of vinyl monomers using both heterogeneous and homogeneous reaction conditions. The hydrophilic properties of chit-can be modified by blending with poly(viny1 alcohol).

EXPERIMENTAL

Chitosan was prepared from chitin derived from two sources, namely from prawn shells (PS) and crab shells obtained from Sigma Chemicals (SG). The crude prawn waste (10 g) was washed and dried as described previ~usly,~ and sieved to give a particle size range of 500-700 pm. The ground shells were treated with four successive portions of 3% sodium hydroxide solution at a liquor ratio of 6 : 1, and at a temperature of 70°C, with rinsing between each treatment. The first two treatments were for 15 min each, and the last two for