Preparation And Property Of Water-soluble Chitosan

Chitin is the widespread natural material, but it is difficult to dissolve. The study how to become a water-soluble oligomeric chitosan with biological activity will be in great significance in medicine, food, cosmetic and agricultural applications.This paper prepared four different water-soluble oligomeric chitosans. (1) Degradation of chitosan by hydrogen peroxide process is as follows:12% chitosan,60℃,5 h, n (hydrogen peroxide):n (chitosan)= 4.73% yield. (2) Biological agents-The best conditions preparing oligomeric chitosan were:3% substrate concentration,6 U/g enzyme dosage, hydrolysis at 45℃, pH 6.0 for 3 h. (3) Preparation of D-glucosamine hydrochloride by degradation of chitin monosaccharide with concentrated hydrochloric acid:30%HC1, w (HC1):w (chitin)= 1.5, reacted at 100℃for 4 h, the yield was 75%. (4) D-Glucosamine sulfate were prepared by ion exchange method from the D-Glucosamine Hydrochloride.In this paper, a biodegradable seed coating formulation was prepared, with the natural polymer chitooligosaccharide as the bactericidal component, polyvinyl alcohol and glycerol as additives. The effects of the chitooligosaccharide content, glycerol content, degree of deacetylation of chitooligosaccharide on seed coating film tensile strength, elongation, membrane permeability and other parameters were investigated. The results showed that the tensile strength and elongation of the membrane improve with the increase of chitooligosaccharide content and glycerol content. The membrane permeability decreased with the increase of chitooligosaccharide content, but increased with the glycerol content increases. The best ratio of seed coating preparation:chitooligosaccharide 2%, polyvinyl alcohol 4%, glycerol 0.5%, mixing temperature 45℃and mixing time 1 h. This seed coating has good promoting seeds germinated role. Compared with blank experiment, corn seed germination rate is improved 21%. In addition, the seed coating can effective increase crop yield. Compared with conventional beforehand sowing, yield of an acre can increase 32 kg of using this seed coating to process cotton seeds.100 tons of water-soluble chitosan production technology were researched. By comparison of ethanol precipitation, spray drying and vacuum freeze-drying on the appearance and yield, we developed the process of order and formulated the enterprise standards for this product.