Abstract
Intrinsic viscosity of several kinds of cellulose nitrates in acetone was measured related to its degree of nitration and degree of polymerisation by osmotic method. The following observations are made:
(1) _??_η_??_=K.P_??_ is established over a DP range 90-3000.K=1.95×10-3, α=0.91, (N%=ca 13.8%, 20°C, c: g/l)
(2) K is constant indepedent of their degree of nitration. α varies with their degree of nitration (N%) and the following relations were obtained:(a) Over N%=11 α=0.835 N2-0.162N+1.553 (b) Over N%=12 α=0.93-0.055(14.14-N) K=1.95×10-3
(3) Influence of degree of nitration on the flex angle of cellulose nitrate molecules was calculated from Nukushina-Sakurada's viscosity formula of slightly crooked linear molecule. Sine of flex angle varies with the degree of nitration in the same tendency as in α.
