Configurational statistics of polysaccharide chains. Part III. Linear β‐(1 → 4′) xylan and mannan

The characteristic ratio CN = 〈r2〉0/Nlv2 of the β‐D(1 → 4′)‐linked polysaccharides xylan and mannan has been computed as a function of the angle τ at the bridge oxygen atom and the degree of polymerization N. The calculated values of the characteristic ratio CN are very high relative to their free rotational dimensions. The characteristic ratio of these polysaecharides converges to the asymptotic value at low degree of polymerization at higher τ values. The low values of the calculated characteristic ratio of xylan compared to cellulose and mannan for the same τ value indicate that the former is more flexible and assumes a compact configuration. A pronounced difference in the values of the characteristic ratio CN of cellulose and mannan has also been observed lower τ angles (<120°). On the other hand, nearly the same values of CN have been obtained at higher τ angles (120°–125°), which suggests that, cellulose and mannan may have similar configuralons in certain solvents.