The liquid crystalline order, rheology and their correlation in chitin whiskers suspensions.

To explore the concentration range of chitin whiskers (CHWs) aqueous suspensions with the liquid crystalline state, and the correlation between liquid crystalline characteristic and rheology of CHWs suspensions, the CHWs aqueous suspensions with different CHWs concentration, pH value, ionic strength and temperature were prepared. The liquid crystalline characteristic and rheological properties of the obtained suspensions were investigated by polarizing microscope and rotational rheometer. The results showed that the liquid crystalline state of the suspensions appeared at the CHWs concentration of 3.5 wt% and disappeared at 22.5 wt%. Increasing the CHWs concentration, pH value and ionic strength, the values of elastic modulus (G') and viscous modulus (G") increased, and the liquid crystal texture basically became more and more regular and obvious. Moreover, the value of G"/G' was always less than 1, suggesting the elastic behavior of CHWs aqueous suspension. Besides, the effect caused by heating on the elastic modulus was irreversible.