Biological Variation in the Degree of Polymerization of Cotton Lint Cellulose Produced in South Africa Part Ⅰ: Basic Methods and Alternative Treatment of Data

摘要

Size-exclusion chromatography coupled with a multi-angle laser light-scattering de- tector is a proven and effective technique for measuring absolute molecular weights (M_w) and molecular weight distributions of cellulose derivatives. Because cellulose is a natural polymer with much variation, average M_w and degree of polymerization (DP) values are of limited value. By plotting and processing absolute DP distributions as directly calculated from the M_w values, an accurate estimate of the DP distribution of a cellulose sample can be obtained. This approach offers the possibility to extend current data processing, which consists mainly of graphic presentations, to exhaustive statistical analyses of the acquired data, previously not possible.