环氧氯丙烷改性稻草的制备和表征

Preparation of epichlorohydrin-modified rice straw and its characterization

稻草秸秆经碱煮预处理后,用环氧氯丙烷在120℃下以甲苯为溶剂反应1～8h。醚化程度用增重率(weight percent gain,WPG)表示。考察反应时间对醚化产率的影响,并采用傅里叶红外变换光谱、X射线衍射分析、热分析和扫描电镜分析,对所制备的环氧氯丙烷改性稻草进行表征。结果表明,预处理后半纤维素和木质素被去除,醚化反应后,稻草样品的结晶度降低,热稳定性略有降低,表面积增大。

Etherification of rice straw with epichlorohydrin was carried out at 120℃ for 1-8h in toluene with NaOH as a base.The extent of etherification was estimated by the use of weight percent gain（WPG） as an indication.The effects of reaction time on WPG and etherification effect were investigated.Nature rice straw,pretreated rice straw and epichlorohydrin-modified rice straw were characterized by non-destructive techniques,e.g.Fourier transform infrared（FT-IR）,X-ray diffraction（XRD）,thermal analysis（TA） and scanning electronic microscopy（SEM） to investigate the reaction progress and etherification effect.Characterization results indicated that the crystallinity and the thermal stability of the modified rice straw decreases due to the etherification,and the surface became rough after modification.