In the rheological method,relative differential MWD of cellulose is determined by dynamic data according to Tuminello diluted assumption theory,and PDI value of cellulose is calculated through Wesslan function which is a model function of MWD.

• 流变法中；根据Tuminello的“稀释假定”理论；利用动态流变G′和G″的主曲线；计算出纤维素的相对微分相对分子质量分布; 应用Wesslan函数适应法(相对分子质量分布的模型函数)计算出相对分子质量分布的多分散指数(PDI).