An ionic liquid as reaction media for radiation-induced grafting of thermosensitive poly (N-isopropylacrylamide) onto microcrystalline cellulose

作者：Hao, Yan; Peng, Jing^*; Li, Jiuqiang; Zhai, Maolin; Wei, Genshuan

来源：Carbohydrate Polymers, 2009, 77(4): 779-784.

DOI：10.1016/j.carbpol.2009.02.025

• Radiation-induced grafting
• Ionic liquids
• Homogeneous system
• Microcrystalline cellulose
• N-isopropylacrylamide

This paper reports a homogeneous modification of microcrystalline cellulose (MCC) in ionic liquids via radiation-induced grafting. Thermosensitive poly (N-isopropylacrylamide) (PNIPAAm) was successfully grafted onto MCC in 1-butyl-3-methylimidazolium chloride ([Bmim]Cl) ionic liquid using gamma-ray irradiation technique at room temperature. The grafting yield (GY) increased with dose up to 40 kGy, while decreased slightly with dose rate from 22 to 102 Gy/min. The results of TGA indicated that cellulose grafted PNIPAAm (cellulose-g-PNIPAAm) had higher thermal stability than that of ungrafted regenerated cellulose (reg-cellulose). The crystalline structure of original MCC was largely destroyed during the dissolution process according to the XRD profiles, and grafting PNIPAAm onto cellulose further decreased the intensity of crystallinity. SEM showed that reg-cellulose and cellulose-g-PNIPAAm films displayed dense and homogeneous morphology. Moreover, the resulting cellulose-g-PNIPAAm exhibited obvious thermal sensitivity with a lower critical solution temperature around 35 degrees C, which was observed from the swelling behavior in water at different temperatures.

• 出版日期2009-7-19
• 单位北京大学