The freezing-thawing cyclic (FTC) treatment was applied to assist destroy the compacted crystal structure and hydrogen bonding interactions in chitin (CH).It finally made chitin instantly dissolved in 8 wt% NaOH/4 wt% urea aqueous solution

subsequently a transparent homogeneous alkaline chitin solution was successfully obtained.The alkaline chitin solution was directly mixed with the initiator (ammonium persulfate

APS)

the water-soluble monomer (acrylic acid

AA) and the crosslinker (N

N'-methylenebisacrylamide

MBA)

then synthesis of chitin-g-poly(acrylic acid) superabsorbent polymers (SAP) was carried out in a thermostatic water bath by static solution polymerization method.The SAP was simply prepared by grafting the sodium polyacrylate chain onto the chitin backbone.The variety of factors that may affect the water absorption capacity and the yield of products were investigated

including the amount of AA

NaOH

MBA and APS

the reaction temperature

as well as the reaction time.The yield of the polymer synthesized under the optimum conditions was 85%.It can absorb 1251

455

84 and 77 gg-1 distilled water

running water

normal saline and artificial urine

respectively.Furthermore

the samples were preliminary characterized by Fourier translation infrared spectroscopy (FTIR) and X-ray diffraction (XRD).Results showed that the graft copolymerization reaction occurred between chitin and acrylic acid

rather than a simple physical blending of chitin and sodium polyacrylate.