SOLID-STATE STRUCTURE AND PROPERTIES OF CHITIN CHITOSAN/

During the preparation of different deacetylated degrees of chitin fro m 4.5% to 95%, it has been found that the deacetylation rate varied wi th the pieces size of chitin and the reaction time. The chitosan membr anes prepared by coating its solution on a glass plate and drying it a t different temperatures show different crystal structures and mechani cal properties under the measurement of PLM, XRD and DSC. XRD measurem ent also gives the difference between chitin and chitosan as well as t he similarity of chitin films separately coated from crab chitin, silk worm chitin and squid chitin. The crystal cell of chitosan fiber is de termined as a=0.987 nm, b=0.924 nm, c=1.031 nm and beta=83.29 degrees.