The lyotropic liquid crystalline behavior of chitin is first reported.The results showed that the critical concentration decreased evidently

the average pitch of the helix on cholesteric phase decreased

but the average area of liquid crystalline ordered domain increased

as the molecular weight of chitin increased.The critical concentrations(W/W) in dichloroacetic acid were 0.005

0.015

0.035 and 0.050 respectively for chitin with the molecular weight 2.84×106

1.47×106

9.4×105 and 5.3×105 prepared from different sources.According to theoretical analysis

the chitin has a rigid chain as polypeptides. The extremely low critical cooncentration of chitin will benefit the process of chitin in liquid crystalline phase such as liquid crystalline solution spinning. In two phase co-existed concentration region of chitin with all molecular weight

no droplet texture but liquid crystalline domains with irregular shape appeared.