Cellulose acetate with a low degree of substitution

A cellulose acetate having a total degree of acetyl substitution of 0.4 to 1.1 and having a compositional distribution index (CDI) as specified by a formula of greater than 1.0 to 3.0, the formula expressed as follows:

• CDI=(Measured value of half height width of chemical composition)/(Theoretical value of half height width of chemical composition)
• wherein:
• the measured value of half height width of chemical composition is a half height width of chemical composition determined by HPLC analysis of a cellulose acetate propionate prepared by propionylating all residual hydroxy groups of the cellulose acetate (sample);
• and
• the theoretical value of half height width of chemical composition is specified by a formula:
• Theoretical value of half height width of chemical composition=2·35482√{square root over (3*DPw*(DS/3)*(1−DS/3))}/DPw [Math. 1]
• where:
• DS represents the total degree of acetyl substitution;
• and
• DPw represents a weight-average degree of polymerization determined by a GPC-light scattering method using a cellulose acetate propionate prepared by propionylating all residual hydroxy groups of the cellulose acetate (sample).