Abstrakt

Physicochemical methods for determination of cellulose crystallinity

Michael Ioelovich

Two physicochemicalmethods for determination of crystallinity degree of cellulose have been developed. The first method was to study the sorption ofwater vapor (A), and secondwas tomeasure the enthalpy of wetting (ÄH). These methods are based onmechanismof interaction between cellulose and molecules of water, which is carried out in the amorphous domains of the polymer. Thus, increase in content of amorphous domains and decrease in degree of crystallinity leads to rise of water sorption and enthalpy ofwetting.As a result, an equation for calculation of the crystallinity degree (X) of cellulose was proposed: X=1– (Z/Zo), where Z is a physicochemical parameter (Aor ÄH) of the sample,Two physicochemicalmethods for determination of crystallinity degree of cellulose have been developed. The first method was to study the sorption ofwater vapor (A), and secondwas tomeasure the enthalpy of wetting (ÄH). These methods are based onmechanismof interaction between cellulose and molecules of water, which is carried out in the amorphous domains of the polymer. Thus, increase in content of amorphous domains and decrease in degree of crystallinity leads to rise of water sorption and enthalpy ofwetting.As a result, an equation for calculation of the crystallinity degree (X) of cellulose was proposed: X=1– (Z/Zo), where Z is a physicochemical parameter (Aor ÄH) of the sample,