The characterization of the product by 1HNMR,IR,UV revealed that dextan could be modified by OLL and the grafting rate(the number of oligomers per 100 glucopyranose units of dextran)could be effectively controlled by molar ratio of the reactants.

• 1HNMR,IR,UV表征改性后产物显示OLL在葡聚糖上的接枝率(葡聚塘的100个葡萄糖单元上OLL的数目)可以通过调节反应物摩尔比得到有效的控制。