@     @
TITLE Development of biodegradable super absorbent polymer made of polysaccharides
(Joint Program to Promote Technological Development with the Private Sectors)


ABSTRACT The super absorbent polymer (SAP) is utilized to disposable sanitary products, e.g. napkins, diapers, etc.  The SAP consisted of polyacrylate is produced more than 105,000 tons/y in Japan, being petroleum as the raw material and consuming enormous energy.  The development of biodegradable polymer has dramatically progressed recently, which made it possible to make sanitary products out of biodegradable materials except SAP.  The purpose of our development is to establish a low energy consumption process to produce biodegradable and safe SAP comprised of polysaccharides, and to propose a method to ease problems about greenhouse gas emission and waste management.

We have been working on the development of biodegradable SAP made of polysaccharide cross-linked with multivalent metal ions. The SAP made of cellulose derivatives had superior repetition absorption speed, however, its blood retaining capacity was inferior. This year, we have worked on the improvement of its blood retaining capacity, the expansion of production capacity, the reduction of amount of alcohol used in the process, and the confirmation of its high safeness. On the other hand, we have also worked on the improvement of performance about other blood absorbing SAP that has high repetition absorption speed but lower absorption capacity. As a result, we have two types of blood absorbing SAP having different performances. Regarding to urine absorbing SAP which is consisted of guar gum derivatives, we have worked on the improvement of its urine absorption capacity, the expansion of production capacity, the confirmation of high biodegradability under aerobic condition. Furthermore, we have investigated about film SAP. Since the film SAP is not on the market yet, it is expected to have capability that makes a new usage. The film SAP made of cellulose derivatives is transparent and flexible, and has saline absorption capacity of 75g for A4 size sheet.